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quarta-feira, 12 de dezembro de 2012

Exercise Testing and Prescription in the Enhancement of Physiologic and Overall Well Being in the Older Adult

Autores: Ellen Glickman, Professor, Exercise Physiology, Kent State University
Tiffany A. Collinsworth ,  Kent State University
Leigh Murray, Assistant Professor, Walsh University


Abstract

Aging is an inevitable process, but the rate and magnitude of the decline in physiologic function may be attenuated by an exercise/activity intervention. The prevalence of chronic disease however increases through the lifespan. Therefore there is a greater need to indirectly assess the individual’s aerobic capacity, muscular strength, body composition, flexibility and balance in an effort to formulate an individualized program of exercise for the older adult. Once these parameters are gathered the individual can engage in a program of exercise that includes: a) a warm up that emphasizes balance and flexibility, b) stimulus to augment the workload safely on the cardiovascular system as well as the bone and peripheral skeletal muscle, and c) concluding with a cool down to slowly bring the individual back to baseline. Therefore, this presentation will discuss the overall benefits of exercise for the older adult and integrate into the presentation and overview of the exercise program for the older adult that is organized at Kent State University. In addition, the data that we have collected will be integrated into the presentation as well as exercise programming that we have conducted on individuals that have special consideration.

Introduction

Aging is an inevitable process; however the rate and magnitude of the decline in physiologic function may be attenuated by maintaining an active lifestyle. Research now suggests that lifestyle and environmental factors influence much of the physiologic deterioration previously considered “normal aging.” Lifestyle and environmental factors are subject to significant modification with proper diet and exercise (Lamberts, et al. 1997 and Stampfer, et al. 2000). For most people, regular exercise reduces the risk of heart disease by approximately one half when compared with those who are physical inactive (Nieman 2006). Therefore, it is critical to explore the quality and quantity of exercise in the attenuation of chronic diseases and the enhancement of overall physiologic well being.
In the area of exercise physiology current research focuses on assessment related to functional capacity, which relates to overall good health and disease prevention (McArdle 2001). The four major components of health related fitness include cardiovascular fitness, muscular strength and endurance, and flexibility. This paper will focus on the overall benefits of exercise for the older adults in relation to the four major components of health related fitness along with balance. The specific areas addressed include the components of fitness, exercise testing and prescription, and common precautions for the older adult.
Components of Fitness
Aerobic capacity. For most individuals, regular aerobic exercise cannot stop the decline in aerobic capacity associated with aging (Kuller 1986 and Trappe 1996). Changes in volume and intensity of exercise over time likely account for the discrepancies in the decline in maximal aerobic capacity (VO2 max) between individuals. Despite this disparity, research consistently shows that physically active older men and women maintain a higher aerobic capacity that their sedentary (inactive) counterparts (McArdle 2001).
Aerobic capacity is comprised of a central and peripheral component. The central component refers to cardiovascular function while the peripheral component refers to skeletal muscle. Decrements in both of these components are linked to a decline in oxygen delivery and the age-related decline in aerobic capacity.
Central component. The central component is comprised of the heart rate (HR) and stroke volume (SV) which combined equal cardiac output (Q). Cardiac output, or the volume of blood ejected from the left ventricle per beat, also declines with age. A decline in maximum exercise HR represents a well-documented change in cardiovascular function. The literature in this area demonstrates that maximum heart rate typically declines with age in the following manner:
HR max = 220- age (yr)
This age related effect reflects medullary outflow of sympathetic activity which occurs in both males and females (Seals 1994). Since Q = HR x SV cardiac output typically decreases with age in trained and untrained men and women as a result of the age-related decrease in maximum heart rate. In addition, the reduction in the heart’s left ventricular stroke volume contributes to approximately one half of the age-related reduction in blood flow and thereby oxygen consumption. With less blood ejected from the heart per beat, less blood is distributed to the working skeletal muscle therefore producing an overall reduction on maximal aerobic capacity. In addition, the SV also declines as the overall contractile function of the heart declines with age.
Peripheral component. The reduction in overall blood flow and plasma volume accompanies a reduction in an age-related reduction in muscle mass. The lower blood flow to active muscles results from a decrease in capillary to muscle fiber ratio and to an overall reduction in muscle cross sectional area. These changes combine to elicit a reduction in the arteriovenous oxygen difference or the amount of oxygen extracted from the working skeletal muscle (a-vO2 difference). Since there is a circulatory reduction in the amount of blood moving through the system (plasma volume), and the amount of blood ejected from the left ventricle per beat (Q), a-vO2 difference also declines with age. The equation that combines the central and peripheral components is shown below:
VO2 = Q (HR x SV) x a-vO2 difference
Anaerobic capacity (muscular strength and muscular endurance). It is fairly well understood that men and women usually attain their highest strength levels between the ages of 20-40 years whereby muscle cross-sectional area is the greatest. Thereafter muscle strength declines with age. Furthermore, strength loss among the older adult contributes to limited mobility, fitness status, and the potential for increased accidents from muscular weakness, fatigue and alterations in balance (Johnson 1998).
The primary cause of reduced muscle strength even among healthy active men and women is a 40-50% reduction in muscle mass from muscle fiber atrophy and actual loss of motor units (McArdle 2001). In addition, sarcopenia (the progressive loss in muscle cross sectional area and mass) and strength loss with aging reflect the combined effects of progressive neuromuscular deterioration and a chronic decrease in regular muscle load (i.e., exercise) (McArdle 2001). Resistance training can increase muscular strength and endurance in the older adult. Research has suggested that older men demonstrate greater strength gains in muscle size and strength than females however, the percent improvement is similar. Increased muscular strength and endurance has the potential to deter the effects of frailty by increasing mobility and preventing falls and fractures. Therefore, moderate resistance training, or strength training provides a safe means to augment protein synthesis and retention while slowing the inevitable age related loss of muscle mass and strength.
Body composition. Research suggests that after the age of 18 men and women generally gain body fat until their fifth or sixth decade. It is well established that excess body fat is associated with hypertension, type 2 diabetes, stroke, CAD, and hyperlipidemia. (United Stated Department of Health and Human Services,1996.) After the age of 60, total body mass (body weight) decreases despite the fact that there is an increase in percent fat which may be the result in a reduction in muscle mass (or lean body mass) and bone mass. The limited longitudinal data in this area appears to demonstrate that a combination of habitual anaerobic and aerobic exercise produce beneficial changes in body composition ( i.e., less of a reduction in muscle mass and less of an increase in percent body fat).
Flexibility. Flexibility is the ability to move a joint through its complete range of motion (ROM). Adequate flexibility is necessary to carry out activities of daily living (ADL’s). Flexibility depends on a number of specific variables, including distensibility of the joint capsule, adequate warm up and muscle viscosity. Additionally, “tightness” of the various other tissues such as ligaments and tendons affects the ROM (ACSM 2006). Joint flexibility is decreased as connective tissue becomes stiffer and more rigid with aging. Appropriated exercises that regular move joints through there full range of motion has been found to increase flexibility 20-50% in men and women of all ages. Just as muscular strength is specific to the muscles involved, flexibility is joint specific; therefore no single flexibility test can be used to evaluate total body flexibility (ACSM 2006).

Balance

Aging often attributes to a decline in balance. Balance maintenance relies upon multiple systems, including visual, somatosensory and vestibular. A dynamic equilibrium between sensory and motor systems must be achieved (Rose 2003). Impaired balance, experienced by many older adults, tends to reduce their sense of comfort and security. This transforms to a fear of falling and thereby limits their socialization and performance of daily activities (Brill 2004). Many of the age-related changes can be reversed or compensated for when identified (Rose 2003). Various screening tests are available to assess individual’s functional limitations. The results can serve to design individualized balance and mobility programs. Research has shown that programs including flexibility, resistance exercise, walking, strength training, and dancing have exhibited improvements in balance (Mazzeo, et al. 1998). Tai Chi programs have also been successful for balance and coordination training thereby reducing the risk of falls (Choi, et al. 2005, Cotton, et al. 1998, Li, et al. 2004, and Mazzeo, et al. 1998).

Exercise Testing

To aid in the development of a safe and effective exercise prescription and optimize safety during exercise testing, it is important to screen potential participants for risk factors and or symptoms of various cardiovascular, pulmonary, and metabolic diseases as well as conditions that may be aggravated by exercise (ACSM 2006). The preparticipation evaluation can determine the extent of medical evaluation necessary prior to exercise testing. ACSM recommends preparticipation health screening to assist in identifying individuals with the following conditions:
1. Identification and exclusion of individuals with medical contraindications to exercise
2. Identification of individuals at increased risk for disease because of age, symptoms, and or risk factors who should undergo a medical evaluation and exercise testing before starting an exercise program
3. Identification of persons with clinically significant disease who should participate in a medically supervised exercise program
4. Identification of individuals with other special needs
A comprehensive pre-exercise test evaluation in a clinical setting generally includes a medical history, physical examination, and laboratory tests.
Exercise programs for the older adult should focus on increasing or maintaining the health related and physiologic components of fitness. According to ACSM, 2006 the purpose of health related fitness testing is as follows:

1. Educating participants about their present health related fitness status relative to health related standards and age and sex matched norms
2. Providing data that are helpful in development of exercise prescriptions to address all fitness components
3. Collecting baseline and follow- up data that allow evaluation of progress by exercise program participants
4. Motivating participants by establishing reasonable and attainable fitness goals
5. Stratifying cardiovascular risk
A well rounded fitness test includes the assessment of the four major components of health related fitness; body composition, cardiorespiratory fitness, muscular strength and endurance, and flexibility. It is important to include balance when assessing older adults.
Older adults should strive to maintain their independence and functional abilities as long as possible. One of the limitations to this end is the ability to maintain balance when performing ADL’s. The inability to accomplish these tasks can lead to an increased susceptibility to falls. More than one third of adults 65 years or older fall each year (CDC 2006). Falls are the leading cause of injury deaths among older adults and the most common cause of non fatal injuries and hospital admissions for trauma. Hip fractures account for the greatest number of falls cause the greatest number of deaths, and lead to the most severe health problems and reduction in quality of life (CDC 2006).
Risk factors for falls include lower body weakness, problems with balance and coordination, and taking four or more medications or any psychoactive drugs. Other risk factors include Parkinson’s disease, history of stroke, previous falls, arthritis, multiple risk factors and cognitive or visual impairments (CDC 2006). Balance and coordination are often the most overlooked areas for exercise testing and prescription of the older adult. Incorporating balance into the exercise testing and prescription is essential in the prevention of falls.
Exercise Energy Expenditure Goals: Epidemiology versus Exercise Physiology and the Health Related Benefits of Exercise.
The interaction of frequency, intensity, duration and mode of exercise determines the caloric expenditure from a given activity. It has been generally accepted that many of the health related benefits and training adaptations associated with increased physical activity are related to the total amount of work accomplished (i.e., energy expenditure). However, the energy expenditure required to elicit significant improvements in VO2max, weight loss, or a reduced risk of premature chronic disease vary. Therefore, exercise prescriptions should be designed with energy expenditure (as well as intensity and duration principles) as a much needed requirement.
The American College of Sports Medicine suggests that every day an individual expend approximately 150-400 kcal by engaging in physical activity (GETP 2006). The lower end of the range is equivalent to approximately 1000 kcal per week from physical activity, which has been demonstrated by Paffenbarger et al. to be associated with a significant reduction (20-30%) in all causes of mortality. An energy expenditure of 100 kcal per week however, is not sufficient for weight loss or weight control. Recent research has indicated that 60 min or more per day may be necessary for weight loss and maintenance, which is double the current recommendation for health-related physical activity (ACSM Position Stand 2001).
Further, the relationship between physical inactivity and coronary heart disease suggests that the lack of regular exercise contributes to heart disease almost in a cause and effect manner; that is, the sedentary person has almost twice the risk of developing heart disease as the most active individual (Powell 1987). Therefore, the strength of the association between the lack of exercise and heart disease risk equals that observed for hypertension, cigarette smoking, and high serum cholesterol. This makes physical inactivity the greater heart disease risk, since more people lead sedentary lifestyles than possess one or more other primary risks factors (McArdle 2001). The life-protecting benefits of exercise are linked more with preventing early mortality and potentially altering the individual’s quality of life, than with extending life span. It is interesting to note that only light to moderate regular activity such as walking, gardening, stair climbing produce health benefits for previously sedentary middle-aged and older men and women. These sedentary individuals represent the largest segment of the population that is at the greatest risk (Bouser 1999).
One of the most pivotal research papers on atherosclerosis in young American soldiers killed in Korea showed upon autopsy, advanced lesions in men whose average age was 22 years (Enos 1953). These research findings shocked the medical community and started to focus the attention on the notion that the atherosclerotic process may begin as early as childhood. We now know that fatty streaks and clinically significant plaques develop rapidly during adolescence and through the third decade of life (Hubinger 1997).
Coronary heart disease is the leading health problem and the primary cause of death. It is also the most expensive condition to treat and resource-intensive chronic condition (McArdle 2001). Research over the past 40 years has identified various personal characteristics, behaviors, and environmental factors linked to the incidence of coronary heart disease (CHD). Although research suggests that many of the risk factors are related to CHD risk, a cause and effect relationship does not exist between these factors. The modifiable risk factors include:
Diet
Elevated blood lipids
Hypertension
Personality and behavior pattern

Cigarette smoking
High serum uric levels
Sedentary lifestyle
Pulmonary function abnormalities
Excessive body fat
Diabetes mellitus
ECG abnormalities
Tension and stress
Poor education
Elevated homocysteine levels
The non modifiable risk factors of the risk factors that cannot be changed include:
Age
Gender
Ethnic background
Male pattern baldness (crown of the head, may be due to elevated androgen levels)
Family history

High levels of physical activity have been associated with lower CHD incidence rates of the Masai tribesmen of East Africa (McDonough 1965). Therefore, the linkage between the increase in energy expenditure and the reduction in dietary fat may prove to be beneficial in the reduction of other modifiable risk factors listed above (i.e., obesity, high blood pressure, etc).
Non modifiable risk factors: Age, gender and heredity.
Age represents a risk factor due to its association with other risk factors such as hypertension elevated blood lipids and glucose intolerance. At most ages, women demonstrate a lower risk of death from heart disease than men. It is uncertain if the change in hormone levels of estrogen woman may provide protection against CHD. In regards to genetics, it is fairly well demonstrated that heart attacks that occur early in one’s life may suggest a genetic predisposition to heart disease. Abnormalities may exist in regards to blood lipids, obesity, or a behavioral risk such as smoking, inactivity or obesity which have all been linked to CHD. These modifiable factors represent the “big five” heart disease risks proposed by the American Heart Association Each exists as a potent, independent CHD risk that can change considerably with lifestyle modification (McArdle 2001).
Modifiable risk factor: Exercise (physical inactivity). Research studies have clearly shown that regular physical exercise protects against heart disease. Sedentary men and women are approximately twice as likely to suffer a fatal heart attack as their more active counterparts. Maintenance of aerobic fitness throughout the lifespan provides protection against CHD risk factors and disease occurrence.
Trained aerobic athletes usually maintain a higher HDL-C (high density lipoprotein cholesterol). Further, sedentary men and women that engage in an exercise program also exhibit favorable alterations in HDL-C. Research suggests that exercise intensity and duration exert independent effects in altering CHD risk factors. However, exercise duration exerts the greatest effect on HDL-C, while exercise intensity may modify blood pressure. In most exercise scenarios a favorable change in lipid profile does not require the exercise intensity needed to improve cardiovascular fitness. Further, research suggests that favorable exercise-related lipoprotein changes probably result from enhanced triglyceride clearance from plasma in response to exercise (Schwartz 1992).
Dietary fiber, Insulin and CHD risk. Insulin resistance and associated hyperinsulinemia relate to CHD risk factors of age, obesity, central body fat distribution, smoking, physical inactivity, hypertension, dyslipidemia, and abnormalities in blood clotting factors. Therefore many clinicians and researchers consider insulin resistance and subsequent hyperinsulinemia independent CHD risk factors (Rulge 1998).
Dietary fiber may serve a dual role in the prevention of CHD. First, it may attenuate the insulin response to a meal containing carbohydrate. Further, it may reduce the tendency to accumulate body fat due to the attenuation of insulin’s role in facilitating fat synthesis. Excessive body fat increases insulin resistance, which may lead to hyperinsulinemia. High circulating insulin levels may also cause hypertension, dyslipidemia, abnormalities in blood clotting factors and even vascular injury.

Exercise Prescription

Exercise prescriptions are designed to enhance physical fitness, promote health by reducing the risk of developing chronic diseases (i.e., diabetes, hypertension), and ensure safety during the exercise session. The exercise prescription should consider the individuals health needs, clinical status and exercise interests to enhance compliance. The optimal exercise prescription for an individual is determined by an evaluation of the individual’s response to exercise including their exercise heart rate, rating of perceived exertion, blood pressure, and the electrocardiogram when applicable. A health history questionnaire provides the exercise physiologist additional necessary information utilized in determining the guidelines of the exercise program (i.e., level of monitoring or supervision that an individual may need) or a medical evaluation prior to engaging in any exercise program.
Quality and Quantity of Exercise: The basis of the exercise prescription:
The main goal of the exercise prescription is to produce a change in the personal health behavior of an individual to include habitual physical activity. The essential components of a systematic, individualized exercise prescription include: mode, intensity, duration, frequency and progression.
To maintain aerobic fitness the American College of Sports Medicine suggest aerobic exercise 3-5 days per week, for 20-60 minutes in duration at an intensity that is 50-85% of the maximum heart rate. Although lower intensity, longer duration exercise is recommended for the older adult as it may reduce the risk of injury and provide the needed benefits to the cardiovascular and skeletal muscle (central and peripheral systems). Furthermore, any exercise that is in excess of the aforementioned recommendation (i.e., the equivalent for running 10-20 miles per week) may set the stage for injury.

Components of the Training Session

The exercise program should include a warm-up period (approximately 5-10 min), a stimulus or conditioning phase (20-60 min) and a cool down phase (5-10 min). Cardiorespiratory, flexibility, resistance training, and a balance program should be integral parts of a comprehensive exercise training program. Flexibility can be incorporated into the warm up and/or cool down phase. Resistance training is often completed on alternate days; however both activities can be combined into the same workout (GETP 2006). An adequate balance program can be performed during the conditioning and/or cool-down phases. In addition, it can be incorporated into the flexibility program as well.

Warm up.
The warm up facilitates the transition from rest to exercise, stretches the postural muscles, increases blood flow, and increases body temperature thereby dissociating more oxygen and increasing metabolic rate. The warm-up may reduce the chance of a musculoskeletal injury by increasing connective tissue extensibility, improving joint ROM and function, and enhancing muscular performance (GETP 2006).
The warm up phase of the exercise session should be 5-10 min of low-intensity large muscle group activity which progresses to an intensity at the lower limit of what is prescribed for the individual (base on their HR range, i.e., exercise intensity). In general low-intensity stretching with light resistance bands is recommended before commencing a more vigorous stimulus or conditioning phase of exercise.

Stimulus or Conditioning Phase
The stimulus or conditioning phase includes cardiorespiratory endurance (aerobic phase). Cardiorespiratory endurance refers to the ability to persist or continue in strenuous activity requiring large-muscle groups for a prolonged period of time (GETP 2006). Those who have difficulty sustaining exercise for 30 minutes or who prefer shorter bouts of exercise can be advised to exercise for 10-minute periods intermittently throughout the day. It is recommended to avoid injury and ensure safety, older individuals should initially increase exercise duration rather than intensity.
The goal for the participant engaged in exercise is to seek improvements in the ability to deliver oxygen (O2) to the working muscles via the cardiovascular system (central) and in the muscle’s ability to generate energy with oxygen (peripheral) in an effort to increase their maximal oxygen consumption (VO2 max). The changes in cardiorespiratory fitness are measured by the assessment of one’s VO2 max, which is related to a minimal threshold of frequency, duration, intensity and volume of exercise (Pollock 1998). Genetics also influence the magnitude and rate of change in maximal aerobic capacity. Individuals with a lower initial level of fitness generally demonstrate the greatest increases in VO2 max. In contrast, more modest increases occur in healthy individuals with high initial levels of fitness (GETP 2006).

Muscular Strength
The reduction in muscle strength in older adults contributes to a decline in functional capacity. Resistance training increases muscular strength and endurance in elderly individuals (ACSM 2006) and in turn has the potential to deter the untoward effects of frailty by improving mobility and preventing falls and fractures. Improved muscular fitness may allow the individual to perform activities of daily living with less effort and extend their functional independence. Resistance training should be an important focus of any exercise program, particularly for elderly people. The first several resistance training sessions should be closely supervised and monitored by trained personnel who are sensitive to the special needs and capabilities or elderly people. The first 8 weeks of a resistance training program should begin with minimal resistance to allow for adaptations of the connective tissue elements.
According to the ACSM the following guidelines should be implemented when strength training with older adults:
• Perform one set of 8 to 10 exercises that use all of the major muscle groups
• A set should involve 10 to 15 repetitions that elicit a perceived exertion rating of 12 to 13 (somewhat hard) Borge scale
• As a training effect occurs, achieve an overload initially by increasing the number of repetitions, then by increasing the resistance
• When return from a lay off of more than 3 weeks, start with resistances of 50% or less of previous training intensities, and then gradually increase the resistance.
Older adults should be discouraged from participation in strength training exercises during active periods of pain or inflammation for arthritic patients. Participants should be encouraged to perform exercises in a range of motion that is within a “pain free arc” while completing multi joint exercises as opposed to single joint exercises. Weight training machines are often recommended over free weights as they generally require less skill. They also protect the back by stabilizing the user’s body position, and allow the user to more easily control the exercise range of motion. Older adults should be encouraged to participate in a year round resistance training program. 

Flexibility
An adequate range of motion in all body joints is important to maintaining an acceptable level of musculoskeletal function, balance, and agility. Maintaining adequate levels of flexibility enhances an individual’s functional capabilities and reduces injury potential particularly for older adults. Flexibility programs should focus on major joints in the body including the; hip, back, shoulder, knee, upper trunk and neck region. ACSM recommend static stretching, which involves slowly stretching a muscle to the end of the range of motion and then holding that position for an extended period of time (15-30 seconds). The optimal number of stretches per muscle group is 2 to 4. Flexibility exercise should be performed in a slow, controlled manner with a gradual progression to greater range or motion.

Cool down
The cool down period provides a gradual recovery from the endurance or stimulus phase of exercise. The cool down is critical to attenuate the exercise-induced circulatory responses, return HR and BP to their near resting values, and maintain venous return which thereby reduces the potential for exercise induced hypotension (drop in BP). The cool down phase facilitates the dissipation of body heat and may promote the removal of the by product of metabolism, lactate.
The cool down has a unique goal especially for the cardiac or high risk patient as this is the phase of exercise in which cardiovascular complications may occur. It is assumed that the sudden termination of exercise and thereby blood flow and the muscle pumps may result in an abrupt decrease in venous return, and possibly reducing coronary blood flow when HR and myocardial oxygen demands are still very high (GETP 2006). Therefore the cool down phase is a critical ingredient in a comprehensive safe exercise program for all individuals.
Precautions
When working with the older adult, there are several health-related conditions that need to be evaluated prior to beginning an exercise program. When conducting the general health screening prior to the start of an exercise program, it is important to note pathological conditions such as osteoarthritis, osteoporosis, previous total hip or knee replacements, previous hip fractures, history of tendonitis or other inflammatory conditions, degenerative disc disease, and spinal stenosis. These conditions are common among older adults and therefore the exercise professional should take special care when administering exercise tests and techniques to these individuals.
Osteoarthritis (OA) is a common pathology that entails degenerative changes occurring in various joints of the body. This occurs as a result of an alteration in the structure of the articular cartilage within the joint due to injury or the aging process. OA can decrease the body’s ability to absorb shock and distribute forces applied to the joints with everyday activities. This force application can be accentuated with certain exercise activities, specifically weight-bearing activities. Therefore, educating the client is important in preventing exacerbation of their symptoms and ultimately their participation in an exercise program.
Bone loss is an inevitable event that occurs with aging. Many individuals exhibit excessive bone loss resulting in osteopenia and osteoporosis. These individuals are susceptible to fractures due to alterations in the structure of their bone. The most common areas are the vertebra bodies of the lumbar and lower thoracic region, the femoral neck of the hip, and the distal radius of the wrist. Research suggests that many falls that occur with the older adult are the result of a fracture of that bone just prior to the fall occurring. Excessive weight-bearing activities i.e., excessive resistance with weight training, may not be indicated. These individuals need to find a delicate balance between exercise that will promote bone health and exercise that is not beneficial. It is important for exercise professionals to identify the individuals at risk and modify their exercise regimen accordingly.
Many older adults, due to arthritic changes and/or falls, may have had surgical procedures such as total knee and hip replacements and hip fracture repair with internal fixation devices (plates and screws). When these surgical interventions are performed, screws, plates, and prosthesis are inserted into the bone of the individual. The bone structure will be altered and depending on the procedure, bone formation and resorption can be altered. This could result in atrophy and/or hypertrophy of the bone in different locations in the affected area. They may demonstrate decreased ROM and balance when compared to their normal, health counterparts. Many times, the surgical components may not allow for the resumption of “normal ROM”. Although the functional independence of these individuals is generally restored, the exercise professional should take special care when establishing an exercise program for these individuals.
Inflammation is a common process that occurs with any activity. However, if the inflammatory process becomes elevated, it may result in conditions such as tendonitis or bursitis. Aging affects the connective tissue components of muscles, tendons, joint capsules, and many other components of joint structure. Inflammation can cause pain, decreased ROM, alterations in posture, and decreased ability to conduct activities of daily living. When prescribing exercise programs for the older adult, any history of inflammatory conditions must be noted and taken into consideration when performing ROM, flexibility and strengthening exercises. Exercise professionals must carefully monitor the client’s response to the number of repetitions and sets with regard to muscle strengthening.
Finally, degenerative disc disease (DDD) and spinal stenosis (SS) are two common diagnoses seen in the elderly population. Degenerative disc disease entails the destruction of the disc that lies between each vertebra, ultimately narrowing the space between each vertebra and possibly causing nerve compression. Spinal stenosis is a narrowing of the canal which contains the spinal cord or the foramen in which the spinal nerves exit the spinal cord. Spinal stenosis may occur due to arthritic changes on the vertebrae itself. Symptoms for DDD and SS may include pain and numbness in the lower extremities, muscular weakness, and sensory deficits. The exercise professional may need to alter exercise positions for these individuals so as to decrease the risk of symptom exacerbation.

Conclusion
Participation in a regular exercise program is an effective intervention associated with aging (ACSM 1998). With the appropriate exercise screening, testing and prescription the older adult is able to benefit from participation in an individualized exercise program. Exercise testing and prescription for the older adult should focus on cardiorespiratory endurance, muscular strength and endurance, flexibility and balance. Benefits associated with exercise include achieving optimal body composition, increased muscular strength and endurance, flexibility, and balance. Regular physical activity has also been shown to increase functional capacity which contributes to leading a healthy, independent lifestyle with greater quality of life.

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Published by the Forum on Public Policy
Copyright © The Forum on Public Policy. All Rights Reserved. 2006.




A Atuação do Fisioterapeuta em Programas de Reabilitação Cardíaca


The role of the physiotherapist in programs of cardiac rehabilitation.

Trabalho realizado por:
Adriana Vieira de Souza Lima Cruz.

Resumo

Estudos apontam as doenças coronarianas como uma das principais causas de óbito em todo mundo. A reabilitação cardíaca objetiva reduzir os efeitos deletérios de prolongado repouso no leito, o controle das alterações psicológicas e a redução da permanência hospitalar. Objetivo: Discutir a atuação da fisioterapia na reabilitação cardíaca. Métodos: Trata-se de um estudo de revisão de literatura. O levantamento de referencial bibliográfico foi realizado por meio das bases de dados SCIELO, LILACS dentre outros meios, como livros, e sites específicos nesta temática. Conclusão: Conclui-se que a reabilitação cardíaca tem como benefício a recuperação global do paciente, sendo de extrema importância a atuação do fisioterapeuta na prescrição dos exercícios.

Descritores: Fisioterapia, Reabilitação Cardíaca, Exercício


Abstract


Studies indicate coronary heart disease as a major cause of death worldwide. Cardiac rehabilitation aims to reduce the deleterious effects of prolonged bed rest, control of physiological changes and the reduction of hospital stay. Objective: To discuss the role of physiotherapy in the cardiac rehabilitation. Methods: This study is a literature review. The collection of bibliographic references was conducted through the databases SciELO, LILACS among other means, such as books, and specific sites on this topic. Conclusion: We conclude that cardiac rehabilitation is to benefit the overall recovery of the patient, it is extremely important the role of the physiotherapist in the prescription of exercise

Descriptors: Physical Therapy, Cardiac Rehabilitation, Exercise


Introdução


Atualmente a doença coronariana é a maior causa de morbidade e mortalidade em países industrializados da Europa e da América do Norte. Cerca de 30% de todos os óbitos ocorridos no Brasil, tem as doenças cardiovasculares como responsáveis, sendo o infarto agudo do miocárdio sua principal causa.

A incidência de patologias cardiovasculares nos países desenvolvidos vem aumentando a cada ano, com 80% relacionadas à doença arterial coronariana, na qual na maioria das vezes, a cirurgia de revascularização do miocárdio se faz necessária.

O primeiro estudo brasileiro sobre risco cardiovascular, ocorrido em 1990, demonstrou que na cidade de São Paulo 69,3% dos indivíduos acometidos por cardiopatias eram sedentários. No decorrer dos anos, a prática de exercícios físicos foi descritas ora como aliada, ora como deletéria, no controle e tratamento de pacientes com doenças cardiovasculares.

Pacientes cardiopatas sem contra-indicação para realizar exercício físico podem fazer a reabilitação cardíaca. Estudos avaliaram evolução significativa no tratamento de pacientes com doença arterial coronária em pacientes que realizaram um programa de reabilitação cardíaca. Este fato alterou os dados demográficos dos pacientes candidatos à reabilitação cardíaca.

Os pacientes que realizam angioplastia coronária têm benefícios evidentes na realização de programa de reabilitação cardíaca. Aqueles com falência cardíaca congestiva são também candidatos a um programa de reabilitação, entretanto algumas modificações neste são necessárias, este é o caso dos pacientes transplantados do coração.

A Sociedade Brasileira de Cardiologia (2006), define a reabilitação cardíaca como um programa multidisciplinar, que envolve médico, psicólogo, nutricionista, educador físico, enfermeiro e fisioterapeuta e tem como objetivo a reabilitação de pacientes cardiopatas, inclusive pós IAM.

De acordo com as Diretrizes de Reabilitação Cardíaca a prescrição de exercícios deve ficar a cargo de profissional especializado em exercício físico, como o fisioterapeuta.

De forma geral, nos pacientes cardiopatas, programas de condicionamento físico resultam em melhora da capacidade funcional, além de redução da freqüência cardíaca, pressão arterial sistólica e da concentração plasmática de catecolaminas em intensidades submáximas de exercício.

Revisão da literatura

Aspectos da Reabilitação Cardiovascular (RC)


A Organização Mundial da Saúde define a Reabilitação Cardíaca (RC) como sendo “o conjunto das intervenções necessárias para fornecer ao doente cardíaco uma condição física, psicológica e social tão elevadas quanto possível, de forma que os doentes com patologia crônica ou pós aguda possam, pelos seus próprios meios, preservar ou retomar o seu lugar na sociedade”.

Pryor e Webber (2002) relatam que, durante os anos 50, os programas de reabilitação envolviam principalmente pacientes com doença arterial coronariana acometidos pelo Infarto Agudo do Miocárdio (IAM). Nessa época, baseados no pressuposto de que a inércia facilitaria o processo de cicatrização, os médicos recomendavam repouso de três semanas.

Com o passar do tempo, observou- se que o repouso prolongado no leito resultava em alguns efeitos deletérios e a atividade física promovia vantagens. Uma vez que o exercício físico pode aumentar a capacidade da função cardiovascular e diminuir a demanda de oxigênio miocárdico para um determinado nível de atividade física.

Hoje, os pacientes saem do leito hospitalar após poucos dias da admissão, retornam para casa 7 a 10 dias depois de disfunções IAM. Além disso, a RC foi ampliada e passou a envolver pacientes acometidos por outras cardiopatias, bem como aqueles em recuperação de angioplastia coronariana ou cirurgia cardíaca.

De acordo com a Sociedade Brasileira de Cardiologia (2004), a reabilitação cardíaca permite aos cardiopatas retornar, o quanto antes, à vida produtiva e ativa, a despeito de possíveis limitações impostas pelo seu processo patológico, pelo maior período de tempo possível. Além de restaurar, nesses pacientes, sua melhor condição fisiológica, social e laborativa; prevenir a progressão, ou reverter o processo aterosclerótico, nos pacientes coronariopatas; reduzir a morbimortalidade cardiovascular e melhora da sintomatologia de angina de peito, ou seja, aumentar a quantidade e a qualidade de vida com relação a custo/efetividade conveniente.

Segundo Dias, Matta e Nunes (2006), o início da terapia de reabilitação cardíaca é definido pela equipe médica, levando em consideração a evolução do paciente, baseado na classificação de Killip-Kimball, que é uma classificação de gravidade baseada em evidências da presença de insuficiência cardíaca ou choque cardiogênico.

Descrição da RC e suas diferentes fases

Em decorrência de novos conceitos de estratificação de risco e manejo, as fases da reabilitação pós-infarto, divididas em 1, 2 e 3, de acordo com a Sociedade Brasileira de Cardiologia (2004), atualmente sendo denominadas fase hospitalar e fase ambulatorial. Há também aquela fase pós-hospitalar, fase 4, encontrada nesse estudo bibliográfico.

Na fase hospitalar são as atitudes de reabilitação tomadas durante o período compreendido desde o início do evento coronariano até a alta hospitalar, enquanto que a ambulatorial corresponde à reabilitação após a alta hospitalar.

Os objetivos da Fase 1 incluem a educação do paciente e da família, deambulação e realização de exercícios de pequena intensidade com o objetivo de prevenir problemas associados ao repouso prolongado no leito e a preparação para um tipo de vida mais ativo após a alta hospitalar. A Fase 2 representa um programa precoce de pós hospitalização, que consiste em grupos de exercícios monitorados e supervisionados por médicos, educação do paciente e de sua família.

A Fase 3 é realizada em casa, hospitais, clínicas especializadas ou centro comunitários, onde o principal objetivo é alcançar um nível de função compatível com a ocupação profissional de cada paciente, ou até mesmo, sua preferência recreativa. Os programas da fase 4 são uma continuação da fase 3 e representam a fase de manutenção a longo prazo do ganho funcional já adquirido após a recuperação. Os programas dessa fase são comparáveis aos programas de condicionamento físico a adultos sedentários.

Fase 1 – Hospitalar

A fase 1 dos programas de Reabilitação Cardiovascular têm início ainda dentro da unidade coronariana. Ela é composta por exercícios de baixa intensidade, que “durante a internação hospitalar têm se mostrado seguros praticáveis e benéficos, embora não seja observada nenhuma melhora na aptidão cardiovascular com atividades de baixa intensidade” (FARDY, YANOWITZ e WILSON, 1998).

Normalmente esse tipo de atividade é prescrito pelo médico do paciente e usualmente é de responsabilidade do fisioterapeuta ou enfermeiro que podem também contribuir no programa.

Titoto et al (2005) relata que o tratamento fisioterapêutico na fase hospitalar baseia-se em procedimentos simples, como exercícios metabólicos de extremidades, para aumentar a circulação, exercícios respiratórios para eliminar obstruções respiratórias e manter os pulmões limpos, exercícios ativos para manter a amplitude de movimento e elasticidade mecânica dos músculos envolvidos, treino de marcha em superfície plana e com degraus, reduzindo os efeitos prejudiciais do repouso prolongado no leito, com isso aumenta a autoconfiança do paciente e diminui o custo e a permanência hospitalar

Os objetivos dessa fase incluem reduzir o tempo de permanência hospitalar e diminuir os problemas de descondicionamento associados com o repouso prolongado no leito, como atrofia muscular, hipotensão postural e deterioração circulatória geral.

Nessa fase a duração total dos exercícios devem ser em torno de 20 minutos, duas vezes ao dia. Durante o exercício, o aparecimento de alguns sinais e sintomas, tais como: fadiga, dispnéia, cianose, palidez, náuseas, 20 bpm acima da freqüência cardíaca de repouso e pressão sistólica 20 mmhg acima dos níveis de repouso e ainda o índice de percepção de esforço de Borg, indica a interrupção do exercício. A hipotensão arterial indica grande comprometimento da função de bomba ventricular, sendo critério de exclusão do programa de reabilitação3.

Fase 2 e 3 - Ambulatorial


Segundo Marques8 (2004) fase 2 da reabilitação cardíaca é um programa supervisionado para pacientes que receberam alta hospitalar, de exercícios prescritos de forma individual e alternativa de modificação do estilo de vida. “O programa de exercício deve ser individualizado em termos de intensidade, duração, freqüência, modalidade de treinamento e progressão” (SOCIEDADE BRASILEIRA DE CARDOLOGIA, 2005).

Essa fase deve também ser realizada sob a supervisão do médico, como ato contínuo a fase 1. O período de exercícios pode ser iniciado 24h após a alta hospitalar, sempre considerando o estado clínico do paciente. Tem duração prevista de 3 a 6 meses, podendo em algumas situações se estender por mais tempo.

Esta fase tem como objetivo melhorar a função cardiovascular, a capacidade física de trabalho, endurance, flexibilidade, educar o paciente quanto à atividade física, modificação do estilo de vida, melhorar o perfil psicológico, preparar o paciente para o retorno de suas atividades.

Após o término bem sucedido da fase 2, o paciente passa para a 3, que pode ser realizada em casa, clínicas especializadas, programas comunitários ou em outro local com supervisão. Durante a fase 3, a prescrição de exercícios deve ser revista periodicamente, incorporando os ganhos obtidos.

O objetivo da fase 3 é promover adaptações no sistema cardiovascular, para que os pacientes retornem, o quanto antes, às atividades profissionais, esportivas e de lazer com maior segurança.

A fase 3 é na maioria das vezes um programa supervisionado e intermitente monitorizado. Pode ser iniciada em qualquer etapa da evolução da doença, não sendo obrigatoriamente seqüência das fases anteriores. Tem duração prevista de 6 a 24 meses.

Fase 4 – Não-supervisionada

A fase IV é caracterizada por pacientes que optem realizar o tratamento domiciliar, ou em outro ambiente externo. De acordo com Fardy, Yanowitz e Wilson (1998), o programa de exercícios deve ser prescrito por profissional especializado (médico, fisioterapeuta, educador físico), com a finalidade de se obter o benefício clínico e uma melhora contínua da função cardiorrespiratória.

É um programa de longo prazo, de duração indefinida e muito variável. As atividades não são necessariamente supervisionadas, devendo ser adequadas à disponibilidade de tempo para a manutenção do programa de exercícios físicos e às preferências dos pacientes em relação às atividades desportivas recreativas.

Essa fase é geralmente considerada um programa de manutenção, quando a maioria dos parâmetros físicos e fisiológicos estão estagnados. Representa um compromisso com a prática regular de atividade física e controle do estilo de vida, construindo hábitos que necessitam ser levados para toda a vida. Esta fase é também apropriada para indivíduos sedentários sem doença cardíaca, cujo objetivo é melhorar a aptidão física e prevenir problemas de saúde associados à inatividade física. Para estes indivíduos, a fase IV destaca primeiro os ganhos funcionais, o condicionamento e a sua manutenção posteriormente.

Etapas da Reabilitação Cardiovascular 

Para Regenga (2000), o programa de RC envolve três etapas: aquecimento, treinamento e desaquecimento. Segundo o autor é necessário registrar diariamente as respostas de freqüência cardíaca e pressão arterial e dos sinais e sintomas apresentados durante as sessões de tratamento.

O aquecimento deve ter duração de 5 à 10 minutos, sendo efetuados exercícios de alongamentos dinâmicos e aeróbicos e de coordenação associados a exercícios respiratórios. Essa fase tem por objetivo preparar os sistemas músculoesquelético e cardiorrespiratório para a fase de condicionamento.

Na etapa do condicionamento são realizados exercícios aeróbicos e exercícios de resistência muscular; com duração de 40 minutos dependendo da capacidade do indivíduo. A freqüência cardíaca deve ser aferida durante esse período, bem como a pressão arterial.

Marques8 (2008) defende que o condicionamento visa estimular o paciente a uma freqüência cardíaca programada a fim de obter efeito de treinamento. A intensidade do esforço deve ser aumentada gradualmente até o nível de treino programado. Os exercícios aeróbicos, rítmicos e dinâmicos são enfatizados e planejados de maneira a exercitar os grupos musculares das extremidades superiores e inferiores.

Os exercícios aeróbicos envolvem os grandes grupos musculares, têm duração típica entre 20 e 40min, e são capazes de elevar o consumo de oxigênio acima do nível de repouso.3 Este tipo de treino melhora significativamente o funcionamento do coração, pulmões e todo o sistema cardiovascular contribuindo para uma entrega de oxigênio mais rápida por todo o corpo.

Sequencialmente aos exercícios aeróbicos são realizados os exercícios de resistência muscular, que constituem-se de contrações dinâmicas realizadas em três séries com o máximo de repetições possíveis, sem ou com baixa resistência e intensidade, longa duração predominando o fator aeróbico. Não visam hipertrofia muscular, mas sim o aumento no fluxo sanguíneo local e uma melhora ou neoformação vascular.

De acordo com a Sociedade Brasileira de Cardiologia (2005) os exercícios de resistência muscular, anteriormente contra-indicados para cardiopatas em geral, passaram a integrar as prescrições dos programas de RC, pois objetivam preservar e aumentar a força e a potência muscular, ajudando a melhorar a endurance muscular, a função cardiovascular, o metabolismo, os fatores de risco coronariano e o bem estar geral.

Quando exercícios intensos são subitamente interrompidos, rincipalmente se o indivíduo permanece de pé, há uma tendência do sangue em estasiar nos membros inferiores, resultando em uma diminuição do retorno venoso ao coração. Em conseqüência disso há elevação da freqüência cardíaca e aumento da demanda miocárdica de oxigênio. Hipotensão arterial, hipofluxo cerebral com cefaléia, tonteira ou desmaio também podem ocorrer como conseqüência.

Por esta razão, com o objetivo de retornar o organismo às condições de repouso com valores de pressão arterial e freqüência cardíaca próximo aos basais e prevenir o aparecimento de lesões musculares, Regenga (2000) defende a realização de cinco minutos de caminhada de baixa intensidade utilizada para prevenir a estagnação do sangue nas extremidades, particularmente nas pernas, três minutos de alongamento associado aos exercícios respiratórios.

O papel do profissional fisioterapeuta nos programas de RC 

A fisioterapia tem sido considerada um componente fundamental na reabilitação de pacientes cirúrgicos cardiovasculares com o intuito de melhorar o condicionamento cardiovascular e evitar ocorrências tromboembólicas e posturas antálgicas, oferecendo maior independência física e segurança para alta hospitalar e posterior recuperação das atividades de vida diária.

As ações do profissional fisioterapeuta nos programas de reabilitação cardíaca concentram-se principalmente nos aspectos físicos da recuperação, “minimizando os efeitos da perda de condicionamento prejudicado pelo repouso no leito e intensificando o funcionamento cardiovascular e músculo-esquelético” (PRYOR e WEBBER, 1998).

A avaliação, condução de exercícios respiratórios e assistidos ou ativos, deambulação supervisionada subida de escadas e outras, são algumas das atividades que devem ser realizadas pelo profissional fisioterapeuta, sempre de acordo com as condições do paciente. Outras funções importantes se destinam à orientação ao exercício, a automonitorização e a descrição das atividades para serem realizadas em casa, pelo paciente.

Discussão

Estudos apontam as doenças coronarianas como uma das principais causas de óbito em todo mundo. Segundo a Organização Mundial da Saúde, a doença coronariana continuará a ser, nas primeiras décadas do século XXI, a principal causa da mortalidade mundial.

Nesses casos de patologias cardiovasculares e outras, inclusive cirúrgicas, indicam-se os programas de Reabilitação Cardiovascular, que se baseiam na reabilitação física com conseqüentes reduções da morbidade e mortalidade, sendo ainda, a redução do estresse emocional, promovidos sob a orientação do profissional fisioterapeuta, de forma supervisionada ou não.

De acordo com as Diretrizes de Reabilitação Cardíaca, o estilo de vida sedentário associa-se a um risco duplamente elevado de doença arterial coronariana, havendo uma redução em torno de 20% a 25% no risco de morte nos pacientes de programa de reabilitação cardiovascular, quando comparados aos que não realizam atividades.

Autores relatam que a atividade física permanente, por meio da fisioterapia, tem grande importância na terapêutica dos pacientes, devendo ser iniciada ainda na fase hospitalar, dando prosseguimento pós-alta hospitalar, o que propicia retorno ao estilo de vida anterior melhor qualidade de vida.

Marques apontam evidencias significativas de que a atividade física aeróbica regular reduz o risco de doença cardiovascular e de que o estilo de vida é freqüentemente considerado um dos cinco maiores fatores de risco para doença cardiovascular.

Conclusões

Atualmente os programas de reabilitação cardíaca vêm sendo desenvolvidas em pacientes enfermos cardiovasculares a fim de propiciar um retorno mais precoce às atividades diárias e com melhor qualidade de vida, objetivando a prática regular dos exercícios físicos com segurança e baixos custos.
Para tanto, o programa de RC precisa ser fundamentado na avaliação contínua e objetiva de suas respostas, por meio da orientação e supervisão do profissional fisioterapeuta. Cada alteração no programa de exercício do paciente precisa ser baseada em uma detalhada avaliação objetiva.

Os exercícios prescritos visam a melhora da a aptidão cardiovascular e aumentam a autoconfiança quando praticados por um período prolongado, promovendo adaptações morfológicas e funcionais no que diz respeito ao sistema cardiovascular e ao sistema muscular.

Referências

1. Rozentul LA, Faria MW, Meirelles RL, Brunini CMT. Efeitos da atividade aeróbia sobre a função cardiovascular na fase III da cirurgia de revascularização do miocárdio. Rev Soc Cardiol Estado de São Paulo 2005;15(3Supl A):9-1

2. Miranda A, Santos M. Análise dos efeitos da pressão positiva expiratória nas vias aéreas no pós-operatório de pacientes submetidos a revascularização do miocárdio. Rev Bras Fisioter 2004 set.;(Supl.)182

3. Leite ML, Bispo MB, Souza TO, Cardoso RF. Intervenção fisioterapêutica na reabilitação cardíaca após infarto agudo do miocárdio. [acesso 10 nov 2011] Disponível em:
http://srvwebbib.univale.br/pergamum/tcc/Intervencaofisioterapeuticana reabilitacaocardiacaaposinfartoagudodomiocardio.pdf

4. Sociedade Brasileira de Cardiologia. Diretriz de reabilitação cardíaca.  Arq Bras Cardiol, São Paulo, v.84, n.5, Mai. 2005

5. Pryor JA, Webber BA. Fisioterapia para problemas respiratórios e cardíacos. 2 ed. Rio de Janeiro: Guanabara Koogan, 2002.

6. Delisa JA. Tratado de medicina de reabilitação. 3ª ed. São Paulo: Ed. Manole; 2002. P. 115- 144

7. Dias AT, Matta PO, Nunes WA. Índices de gravidade em unidade de terapia intensiva adulto: avaliação clínica e trabalho da enfermagem. Revista Brasileira de Terapia Intensiva, São Paulo, v.18, n.3, p. 279- 281, Jul.- Set. 2006.

8. Marques KS. A Interação dos Profissionais de Educação Física e Fisioterapia na Reabilitação Cardiovascular. [monografia]  2004. 61 f. Universidade Federal de Santa Catarina.

9. FARDY, P. S.; YANOWITZ, F. G.; WILSON, P. K. Reabilitação Cardiovascular: Aptidão Física do Adulto e Teste de Esforço. Rio de Janeiro: Revinter, 1998 287p.

10. Titoto L, Sansão MS, Marino LHC, et al. Reabilitação de pacientes submetidos à cirurgia de revascularização do miocárdio: atualização da literatura nacional.  Arquivo Ciência Saúde,  v.12, n.4, p.216- 219, Out.- Dez. 2005

11. REGENGA, M. M. Fisioterapia em Cardiologia: Da U.T.I. à Reabilitação. São Paulo: Roca, 2000. 292 p.

Uncovering subclinical atherosclerosis in evaluation of cardiovascular risk


Authors: Novo S, Pace G, Toia P, Carità P, Corrado E, Novo G
Combining risk calculators such as SCORE (systematic coronary risk evaluation), recommended by the new 2012 European Guidelines on cardiovascular disease prevention in clinical practice with the study of arterial function offers added prediction of cardiovascular risk, which our study on arterial thickness and and a meta-analysis on arterial lesions have helped to support.


Background

New methods for prevention and treatment of cardiovascular diseases have improved by many measures: onset of clinical events is delayed, immediate outcome of disease is better and life expectancy has increased. Still, cardiovascular disease remains the leading cause of mortality, morbidity and deteriorated quality of life, worldwide (1). In Europe alone, over 4 million deaths are due to cardiac and vascular diseases, of which, atherosclerosis, deemed, the "silent killer" is a leading cause.
Indeed, atherosclerosis is a slow, progressive process involving the intima and media tunicae of large and medium arteries resulting in a chronic disease that causes formation of focal lesions (plaques) containing lipids and fibrous tissue (2). When local occlusive thrombus overly atherosclerotic plaque, this process leads to acute cardiovascular events (3).
Subclinical atherosclerosis, or preclinical atherosclerosis, refers to the early stage of the process of atherosclerosis where, within the vascular walls, "something is starting to change": mounting evidence suggests that subclinical atherosclerosis confers an increased risk of cardiovascular disease. Thus, calculation of global cardiovascular risk is a strategy to:
  1. Uncover patients at risk of atherosclerosis and therefore at risk of developing cardio and cerebrovascular events: In preclinical atherosclerosis vascular damage is minimal and can usually be corrected. 
  2. Stratify patients: In subjects without previous cardiovascular disease, reveal the development of events within the next ten years as likely to occur and that will help to decide on any corrective measures to put in place.
New 2012 ESC guidelines on cardiovascular disease prevention in clinical practice (4) recommend using risk charts such as the Systematic Coronary Risk Evaluation Project (SCORE) which offer a total individualised risk estimation using multiple traditional risk factors in adults without evidence of cardiovascular disease.
Carotid intima media thickness is a valuable tool in recognition of pre-atherosclerosis, and a recent meta-analysis confirms that early atherosclerotic lesions of carotid arteries are an independent marker of cerebro and cardiovascular events. Thus, combining SCORE with study of arterial function offers added prediction of risk to help distinguish individuals with high and low absolute risk, improve prevention efforts and help to decide on any investigational measures.

I - Risk

A) Traditional and emerging factors 

As in other diseases, risk factors for atherosclerosis are conditions in healthy and asymptomatic subjects that are related statistically to the beginning of its pathological process. They include: dyslipidemia, diabetes mellitus, hypertension, smoking, overweight or obesity, inactivity or sedentary lifestyle, stress, alcoholism and low consumption of fruits and vegetables (5). These are the modifiable risk factors of atherosclerosis, meaning, the conditions potentially susceptible to correction. Traditional risk factors are modifiable, or not through healthy lifestyle and diet and/or pharmacological treatment. Non-modifiable risk factors are those that cannot be corrected, they are: older age, male gender, family history of cardiovascular disease and genetic predisposition. Added to these traditional risk factors are "emerging" risk factors of atherosclerosis, considered modifiable to a certain extent, such as high levels of triglycerides, and C-reactive proteins which are the conditions that have been identified more recently as casually related to atherosclerosis.

2) Global cardiovascular risk

Global cardiovascular risk is a new approach that has a two-fold aim. It seeks to establish 1) prognosis and 2) each risk factor's role in the atherosclerotic process. The weight attributed to each risk factor is estimated using complex mathematical algorithms built with data provided by large observational epidemiological studies.
According to the 2010 American College of Cardiology Foundation, American Heart Association guidelines, global cardiovascular risk scores involving multiple (traditional) risk factors should be used in all asymptomatic adults without a clinical history of cardiovascular disease but with an increased cardiovascular risk to 1) assess the risk, 2) stratify incidence of probable events in the following ten years, and, at the least, 3) to target preventive interventions.
Until recently, global risk was, together with other various indices, a class IIa of evidence, (i.e evidence obtained from at least one other type of well-designed quasi-experimental study or obtained from well-designed controlled trials without randomisation). Other examples of such indices are the ankle-brachial index: measuring the ankle-brachial index in asymptomatic subjects and in those with low-density lipoprotein or calcium or C-reactive protein levels: among patients whose cholesterol is below 130 mg/dl and without risk factors, calcium or C-reactive protein levels to select those to be initiated with statin therapy (6)
However, the new 2012 European Society of Cardiology Guidelines on cardiovascular disease prevention in clinical practice, state that total risk estimation using multiple risk factors (such as SCORE) is recommended for asymptomatic adults without evidence of CVD and has a level IC evidence,-  i.e. data derived from a single randomised clinical trial or large non-randomised studies or evidence and/or general agreement that a given treatment or procedure is beneficial, useful, effective.

3) Charts

Global cardiovascular risk can be approximately estimated by using risk charts - standardised tables or graphs - or more accurately, through electronic calculators, which deliver an individual score. Resulting risk is absolute - the probable incidence of a major cardiovascular event, i.e. sudden death, non-fatal MI and stroke in the following 10 years -  or relative - the ratio between the investigated subject's risk divided by the average subject's risk, among subjects with the same characteristics. (7-9).

Limitation of risk charts include:
  1. Risk factors: only a few risk factors are included such that some may be omitted.
  2. Groups: considering individuals exclusively from a certain age group or gender.
  3. Follow-up: models of logistic regression restricted to definite follow-up periods (i.e. 10 years) with no difference made between events that occur at relative timepoints, for example at 1, 5 or 10 years.
  4. Assessment: charts are prospectively assessed only in a few subjects, as opposed to a broader scale of patients.
The first cardiovascular risk chart to be introduced was the Framingham risk chart in 1991 as a result of the study by the same name set up in 1948 to investigate an epidemic of coronary disease in the US. It evaluated cardiovascular risk in view to primary prevention and using a prospective, epidemiological approach. (10-14). Thechart reveals the risk of performing major events, myocardial infarction, stroke, sudden death in the following 10 years in subjects with no previous history of cardiovascular disease. It evaluates the traditional risk factors which are age, sex, systolic hypertension, diabetes mellitus, hypercholesterolemia and smoking in males and females between 30 and 74 years of age (10-14). Study of major prospective cohorts have validated its effectiveness in calculating cardiovascular risk in the American population.
In 2003, the European Societies of Cardiology, Hypertension and Atherosclerosis jointly published guidelines for primary prevention of cardiovascular disease which gave way to the European Chart of Cardiovascular risk to evaluate the risk aimed European cohorts of subjects specifically. The algorithmic functions were built using data from longitudinal studies that investigated its populations and cultural habits, with differences made between Northern and Southern European countries on on hand or calibrated to specific countries. The guidelines were subsequently updated, by a Task Force in 2007, and lately, in 2012, where namely, a revised approach of risk in the young yielded revised risk charts.
In Italy, the Institute of Health through the “Progetto Cuore” aimed to better estimate the global cardiovasc
ular risk specific to Italian subjects: specific charts for Italy were built ad hoc from analysing Italian habits and lifestyles. With data from Italian longitudinal studies, conducted between the mid-80s and mid-90s “Progetto Cuore” built a database of the main risk factors. The aims of the project were to: estimate the impact of cardiovascular diseases in its general population through indicators such as prevalence, attack, incidence and mortality rates; evaluate the distribution of cardiovascular risk factors in representative samples of the Italian population and evaluate cardiovascular risk in the Italian population (15). Progetto Cuore investigated various cohorts, made up of both males and females from various Italian regions and reported total and specific mortality, fatal and non-fatal CV events - MI, stroke, coronary death, sudden death and revascularisation interventions for each. Later, Pende A. et al. analysed 84 Italian Caucasian subjects: 50 males and 34 females affected by elevated blood pressure and/or dyslipidemia, but never treated for these reasons. Included for study, was an integrated measure of both carotid wall thickness and presence of plaque the Carotid score. Carotid score giving 1 point (presence of plaque), 0.5 point (presence of increased intima-media thickness) and 0 points (absence of lesions): the final score was the sum of the possible lesions in 10 sites (3 at common carotid artery and at the bifurcation, 1 at internal carotid artery, and 1 at external carotid artery on both sides). A significant associationbetween certain parameters of early cardiovascular damage, of which the Carotid score, and the Progetto Cuore score was demonstrated in both sexes, thus demonstrating the validity of Projecto Cuore.

II - Carotid intima-media thickness 

According to several prospective studies, analysis of arterial function and structure provides added prognostic information compared to conventional risk factors alone. It allows:
  1. Screening for subclinical disease 
  2. Distinguishing those with high and those with low absolute risk of cardiovascular disease 
  3. Implementing efforts for prevention prior to a devastating cardiovascular event 
  4. Investigating possible reasons for increased arterial thickening, such as an occult underlying insulin-resistant condition or residual lipid risk markers. 
1) Screening in low and intermediate risk individuals
Screening should be carried out especially in low-risk individuals with a family history of premature cardiovascular disease or those with any of the National Cholesterol Education Program risk factors which are : current cigarette smoking, hypertension - systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥90 mmHg and/or pharmacological treatment -,  HDL cholesterol level <1 .04=".04" age="age" and="and" any="any" attack="attack" br="br" cardiovascular="cardiovascular" disease="disease" family="family" first-degree="first-degree" heart="heart" history="history" in="in" l="l" men="men" mmol="mmol" nbsp="nbsp" of="of" premature="premature" relative="relative" women.="women." years="years">Measured by B-mode ultrasound, in large-scale population studies carotid intima media thickness is a relatively simple and inexpensive noninvasive technique which can be performed repeatedly without adverse effects on patients. It is associated with CVD and is an independent predictor of stroke and myocardial infarction. In asymptomatic adults at intermediate risk, it is an especially valuable indicator of subclinical atherosclerosis and hence, of cardiovascular risk (16), providing a graded measure of vascular damage. Technical approach and operator training, as well experience performing the test, must be carefully followed to achieve high quality results.
A meta-analysis of 8 population studies analysed the association between carotid intima media thickness and cerebro and cardiovascular events in a total of 37,197 subjects with a mean follow-up of 5.5 years. It showed that an increase in thickness of 0.1 mm was associated with a 15% enhanced risk of for acute myocardial infarction and an 18% enhanced risk or stroke.

2) Subclinical atherosclerosis

On our end, we examined 454 asymptomatic subjects (215 males and 239 females), mean age 57 ± 10 years with a cluster of risk factors, over a five-year follow-up period evaluating the incidence of cardiovascular events. It resulted that events occurred in 38% of subjects at high risk, in 13% and 6% of subjects at intermediate and low risk (p < 0.003). Carotid pre-atherosclerosis was among the evaluated parameters, a predictive marker of cardiovascular events (OR 2.7, 95% IC 1.4–5.1, p < 0.0024). In subjects with global cardiovascular risk < 20% according to the charts of “Italian Progetto Cuore” for subjects with normal carotid ultrasound finding at baseline the prevalence of events was 8%, 13% for subjects with increased IMT and 15% for subjects with ACP (including two deaths). We concluded that carotid intima media thickness is a valuable tool in recognition of pre-atherosclerosis, and our results are in line with a recent meta-analysis confirming that early atherosclerotic lesions of carotid arteries are an independent marker of cerebro and cardiovascular events (17, 18).
Moreover, the Heart Attack Prevention and Education (SHAPE) guidelines recommend noninvasive screening in all asymptomatic men 45-75 years of age and asymptomatic women 55-75 years of age (except those defined as at very low risk) in view of detecting and treating those with subclinical atherosclerosis (19).

3) Improved evaluation of risk
In the Atherosclerosis Risk In Communities study, Nambi et al. found that intima-media thickening and asymptomatic carotid plaque presence improved prediction of coronary heart disease risk. Adding this parameter to the risk prediction model of Framingham, reclassified over 10% of individuals into the higher risk category beyond traditional risk factors.
The study is especially significant in that investigators put forward that small, nonstenotic carotid plaque might be a different phenotype than atherosclerosis, which would carry an important contribution to vascular risk beyond carotid intima media thickening. Plaque presence was defined if two of the following three criteria were met: carotid intima media thickening of 1.5 mm, abnormal wall shape and abnormal wall texture. Thus, investigators concluded that adding plaque and carotid intima media thickening to traditional risk factors improves risk prediction beyond the Framingham chart (20).
Regarding subclinical organ damage, the study of Sehestedt, analysed 1,968 subjects without cardiovascular disease and not receiving treatment. It showed that, beyond Systemic Coronary Risk Evaluation (SCORE), the estimate of subclinical organ damage predicts cardiovascular death, and the combination of both subclinical organ damage and SCORE may improve risk prediction. Risk of cardio Progetto Cuore vascular death was, independently of SCORE, associated with atherosclerotic plaques in the carotid arteries [hazard ratio 2.5 (1.6-4.0)].
Moreover analysing subjects with a SCORE between 1 and 5% (moderate risk), together with the evaluation of subclinical atherosclerosis, increased test sensitivity from 72 to 89% (P= 0.006), but reduced specificity from 75 to 57% (P< 0.002) and positive predictive value from 11 to 8% (P= 0.07) (21).

4) Avoidance of misclassification
Identification of preclinical alterations in arterial function and structure, such as carotid intima-media thickness, stiffness or wave reflection, may refine cardiovascular risk stratification and decrease the chances of misclassification of cardiovascular risk. They are relatively expensive and noninvasive tests, performing by arterial ultrasonography and tonometry, useful to supplement - not to replace - the standard risk assessment algorithms, hence to identify candidates for aggressive therapy, especially in the intermediate-risk group (22,23).
In our experience, which we covered before in a previous edition of the e-journal of Cardiology Practice, the incidence of CV events, in a ten year follow-up, is enhanced in patients with subclinical-ATS, including an increase of 56% and 7% rates (respectively non-fatal and fatal events) in that people considered as low-intermediate risk according to the “Italian Progetto Cuore” Risk Chart (24). Increased IMT or asymptomatic carotid plaque predicts CV events improving the risk stratification of asymptomatic patients aged greater than 45 years, with a cluster of risk factors (4). Carotid intima-media thickness is increasingly used as a surrogate marker for atherosclerosis.
As shown in the study of Roksana et al, assessing subclinical atherosclerosis (especially trough intima media thickness) in multiple arterial sites may yield a better estimate of disease risk than Framingham risk score alone. Its use relies on its ability to predict future clinical cardiovascular end points, allowing appropriate early management in those patients with subclinical atherosclerosis (25).
The evidence for arterial stiffness, assessed as carotid distensibility or aortic pulse wave velocity, as an indicator for risk of cardiovascular disease, is restricted to subjects with either hypertension or end-stage renal disease or based on small studies in renal transplant patients and elderly.
Conclusion
The new ESC 2012 guidelines on cardiovascular disease prevention in clinical practice recommend using SCORE in adults without evidence of cardiovascular disease. On the other hand, our experience shows that carotid intima media thickness is a valuable tool in recognition of pre-atherosclerosis, and a recent meta-analysis confirms that early atherosclerotic lesions of carotid arteries are an independent marker of cerebro and cardiovascular events. Thus, combining SCORE with study of arterial function can help to distinguish individuals with high and low absolute risk, improve prevention efforts and help decide on investigational measures. 

Notes to editor
Novo S. S, MD, FESC, FACC
Via Del Vespro, 129
90139 – Palermo - Italy
Phone:             +39-091-6554316       - fax +39-091-6554301
Chair of Cardiovascular Diseases, Centre for the Early Diagnosis of Preclinical and Multifocal Atherosclerosis and for Secondary Prevention, University of Palermo, Division of Cardiology, University Hospital "Paolo Giaccone", Department of Internal Medicine, Cardiovascular Disease, Palermo, Italy.

Authors' disclosures: None declared. 
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The content of this article reflects the personal opinion of the author/s and is not necessarily the official position of the European Society of Cardiology.