Effects of walking on coronary heart disease in elderly men: the Honolulu Heart Program

Walking and sports participation and mortality from coronary heart disease and stroke

OBJECTIVES

We aimed to examine the impact of exercise on mortality from cardiovascular disease (CVD) in Asian populations.

BACKGROUND

Few data have been available in Asian countries, where job-related physical activity is higher than that in Western countries.

METHODS

Between 1988 and 1990, 31,023 men and 42,242 women in Japan, ages 40 to 79 years with no history of stroke, coronary heart disease (CHD), or cancer, completed a self-administered questionnaire. Systematic mortality surveillance was performed through 1999, and 1,946 cardiovascular deaths were identified. We chose the second lowest categories of walking and sports participation as the reference to reduce a potential effect of ill health.

RESULTS

Men and women who reported having physical activity in the highest category (i.e., walking > or =1 h/day or doing sports > or =5 h/week) had a 20% to 60% lower age-adjusted risk of mortality from CVD, compared with those in the second lowest physical activity category (i.e., walking 0.5 h/day, or sports participation for 1 to 2 h/week). Adjustment for known risk factors, exclusion of individuals who died within two years of baseline inquiry, or gender-specific analysis did not substantially alter these associations. The multivariate-adjusted hazard ratios (95% confidence interval) for the highest versus the second lowest categories of walking or sports participation were 0.71 (0.54 to 0.94) and 0.80 (0.48 to 1.31), respectively, for ischemic stroke (IS); 0.84 (0.64 to 1.09) and 0.51 (0.32 to 0.82), respectively, for CHD; and 0.84 (0.75 to 0.95) and 0.73 (0.60 to 0.90), respectively, for CVD.

CONCLUSIONS

Physical activity through walking and sports participation might reduce the risk of mortality from IS and CHD.

Total and leisure-time walking among U.S. adults should every step count?

BACKGROUND

Although walking is a popular leisure-time activity, a substantial amount of total daily walking occurs in non-leisure contexts (i.e., occupation, transportation, and household work). Because non-leisure walking is not assessed by traditional leisure-time activity surveys, total walking among U.S. adults may be underestimated. This study describes walking estimates obtained from a measure of leisure-time activity and a specific measure of total walking in all contexts.

METHODS

A national sample of adults (n=6626), selected by random-digit dialing, was surveyed between May 1999 and November 2000. Estimates of walking prevalence and of weekly time spent walking were examined from two separate modules: (1) an assessment restricted to leisure-time activity, and (2) an assessment of total walking.

RESULTS

Walking prevalence based on the total walking module was nearly double that based on the leisure-time module (81% vs 43%, respectively). The median weekly minutes of walking also nearly doubled using the total walking module (239 vs 130 minutes, respectively). Among those with jobs involving substantial walking, median weekly walking minutes were more than three times greater with the total walking module (476 vs 130 minutes, respectively).

CONCLUSIONS

U.S. adults, particularly those with jobs involving walking, do a substantial amount of walking not captured by traditional leisure-time activity surveys. This may affect the appropriate targeting of physical activity interventions, as well as the evaluation of the effectiveness of physical activity promotions and policies. However, further characterization of non-leisure walking is needed to determine its contribution to health and meeting physical activity guidelines.

Endothelial flow-mediated dilatation and exercise capacity in highly trained endurance athletes

Brachial artery ultrasound during reactive hyperemia is a noninvasive method of assessing peripheral endothelium-dependent vasodilatation. Aerobic exercise has the potential to improve local endothelial function. We sought to analyze the effects of regular aerobic training on brachial artery endothelial function in endurance athletes. We studied diameter and blood flow of the brachial artery in 32 endurance male athletes and 30 healthy male subjects. In the same subjects flow-mediated dilatation of the brachial artery was recorded by inducing an ischemia through a forearm arterial occluding cuff. Maximal oxygen consumption was significantly higher in the athletes group than in the controls (61.24 +/- 5.43 vs 44.49 +/- 2.68 ml/kg/min, p < 0.001). Flow-mediated dilatation of the brachial artery induced by forearm arterial occlusion in athletes was also higher than that of the control subjects (17.1 +/- 2.3 vs 11.2 +/- 1.7, p=0.002). Furthermore, there was an association between flow-mediated dilatation and VO2max (r=0.69, p < 0.001). Baseline measurements of the diameter and the blood flow volume of the brachial artery were similar in both groups. During reactive hyperemia period, the percent of the changes of endothelial diameters and flow were significantly higher in athletes than in controls. Higher flow-mediated dilatation levels in athletes reflect better vascular adaptation to habitual aerobic exercise.

Can adoption of regular exercise later in life prevent metabolic risk for cardiovascular disease?

OBJECTIVE

To determine the impact of chronic exercise training initiated later in life upon development of metabolic markers of cardiovascular disease risk.

RESEARCH DESIGN AND METHODS

Two inception cohorts of previously sedentary healthy adults aged 55-75 years at baseline (1989), one initiating regular supervised physical exercise training and the other a geographical similar sedentary control, were assessed for anthropometric, biochemical, and clinical markers of the metabolic syndrome and comorbidity over 10 years.

RESULTS

At baseline, active individuals aged 68 years compared with sedentary individuals aged 67 years had similar fitness levels (5.7 vs. 5.8 metabolic equivalents). At follow-up, complete data were obtained for 161 active and 136 sedentary subjects. Drop out occurred primarily because of failure to adhere to the exercise regimen and poor physical health for active and sedentary individuals, respectively. More metabolic abnormalities were seen in the sedentary group than in the active group for one or two (64 vs. 36%, P < 0.001) and three or more (35 vs. 22%, P < 0.003) abnormalities, respectively. In those assessed at follow-up, the sedentary group compared with the active group had lower fitness levels (5.0 [13.8% decrease] vs. 5.9 [3.5% increase] metabolic equivalents), had a greater likelihood of a positive exercise electrocardiogram or symptom (32 vs. 10%, P < 0.001), and had more comorbid conditions (Charlson Comorbidity Index score 0.9 vs. 0.4, P < 0.01).

CONCLUSIONS

Higher fitness achieved over 10 years of regular exercise training in older adults was associated with reduced development of metabolic risk factors for cardiovascular disease, fewer exercise-induced cardiac abnormalities, and reduced comorbidity.

Physical activity and older adults: a review of health benefits and the effectiveness of interventions

The purpose of this multidisciplinary review paper is to critically review evidence from descriptive, efficacy and effectiveness studies concerned with physical activity and older people. Both levels of fitness (aerobic power, strength, flexibility and functional capability) and measures of physical activity involvement decline with age, and the extent to which this is due to a biological ageing processes or disuse (physical inactivity) is critically examined. The review will consider the evidence for a causal relationship between sedentary behaviour/physical activity programmes and cardiovascular, musculoskeletal and psycho-social health, independent living and health-related quality of life into old age. The review also considers the effectiveness of different physical activity interventions for older people and issues relating to cost-effectiveness. The implications for future policy in terms of research, health care services, and education and training are briefly discussed.

Effect of exercise training on endothelium-derived nitric oxide function in humans

Vascular endothelial function is essential for maintenance of health of the vessel wall and for vasomotor control in both conduit and resistance vessels. These functions are due to the production of numerous autacoids, of which nitric oxide (NO) has been the most widely studied. Exercise training has been shown, in many animal and human studies, to augment endothelial, NO-dependent vasodilatation in both large and small vessels. The extent of the improvement in humans depends upon the muscle mass subjected to training; with forearm exercise, changes are restricted to the forearm vessels while lower body training can induce generalized benefit. Increased NO bioactivity with exercise training has been readily and consistently demonstrated in subjects with cardiovascular disease and risk factors, in whom antecedent endothelial dysfunction exists. These conditions may all be associated with increased oxygen free radicals which impact on NO synthase activity and with which NO reacts; repeated exercise and shear stress stimulation of NO bioactivity redresses this radical imbalance, hence leading to greater potential for autacoid bioavailability. Recent human studies also indicate that exercise training may improve endothelial function by up-regulating eNOS protein expression and phosphorylation. While improvement in NO vasodilator function has been less frequently found in healthy subjects, a higher level of training may lead to improvement. Regarding time course, studies indicate that short-term training increases NO bioactivity, which acts to homeostatically regulate the shear stress associated with exercise. Whilst the increase in NO bioactivity dissipates within weeks of training cessation, studies also indicate that if exercise is maintained, the short-term functional adaptation is succeeded by NO-dependent structural changes, leading to arterial remodelling and structural normalization of shear. Given the strong prognostic links between vascular structure, function and cardiovascular events, the implications of these findings are obvious, yet many unanswered questions remain, not only concerning the mechanisms responsible for NO bioactivity, the nature of the cellular effect and relevance of other autacoids, but also such practical questions as the optimal intensity, modality and volume of exercise training required in different populations.

State of the science for care of older adults with heart disease

This article provided an overview of the current state of knowledge related to cardiovascular disease in elders. Some depth has been provided related to CHD and HF, two common diagnoses in older persons. The most striking finding is that although trials are increasingly including older cohorts of patients, research specifically testing known therapies in older patients is essential. In particular, research testing the safety, efficacy, and acceptability of therapies in the oldest old is greatly needed.

Occupational and leisure time physical activity and the risk of nonfatal acute myocardial infarction in Italy

PURPOSE

Physical activity has long been related to a reduced risk of coronary heart disease (CHD), including acute myocardial infarction (AMI). However, the quantitative estimates of the possible protective role of physical activity appear to vary across studies and populations.

METHODS

A case-control study conducted in Italy between 1995 and 1999, including 507 incident cases below 79 years (378 men, 129 women) with a first episode of AMI, and 478 controls (297 men, 181 women) admitted to hospitals for acute conditions.

RESULTS

Compared with the lowest level of occupational physical activity, the multivariate odds ratios (OR) of AMI for the highest level were 0.61 (95% confidence interval [CI], 0.38-0.97) at age 15 to 19 years, 0.57 (95% CI, 0.34-0.95) at age 30 to 39 years, and 0.51 (95% CI, 0.29-0.90) at age 50 to 59 years. The corresponding values for leisure time activity were 0.54 (95% CI, 0.38-0.77), 0.86 (95% CI, 0.57-1.30), and 1.00 (95% CI, 0.57-1.74), respectively. The association was consistent across strata of age, sex, education, smoking, and other selected covariates.

CONCLUSIONS

The attributable risk for low occupational exercise at age 30 to 39 years was over 10%, indicating the scope for further intervention on this modifiable risk factor in this Italian population, particularly in consideration of the public health importance of CHD.

Exercise and the nitric oxide vasodilator system

In the past two decades, normal endothelial function has been identified as integral to vascular health. The endothelium produces numerous vasodilator and vasoconstrictor compounds that regulate vascular tone; the vasodilator, nitric oxide (NO), has additional antiatherogenic properties, is probably the most important and best characterised mediator, and its intrinsic vasodilator function is commonly used as a surrogate index of endothelial function. Many conditions, including atherosclerosis, diabetes mellitus and even vascular risk factors, are associated with endothelial dysfunction, which, in turn, correlates with cardiovascular mortality. Furthermore, clinical benefit and improved endothelial function tend to be associated in response to interventions. Shear stress on endothelial cells is a potent stimulus for NO production. Although the role of endothelium-derived NO in acute exercise has not been fully resolved, exercise training involving repetitive bouts of exercise over weeks or months up-regulates endothelial NO bioactivity. Animal studies have found improved endothelium-dependent vasodilation after as few as 7 days of exercise. Consequent changes in vasodilator function appear to persist for several weeks but may regress with long-term training, perhaps reflecting progression to structural adaptation which may, however, have been partly endothelium-dependent. The increase in blood flow, and change in haemodynamics that occur during acute exercise may, therefore, provide a stimulus for both acute and chronic changes in vascular function. Substantial differences within species and within the vasculature appear to exist. In humans, exercise training improves endothelium-dependent vasodilator function, not only as a localised phenomenon in the active muscle group, but also as a systemic response when a relatively large mass of muscle is activated regularly during an exercise training programme. Individuals with initially impaired endothelial function at baseline appear to be more responsive to exercise training than healthy individuals; that is, it is more difficult to improve already normal vascular function. While improvement is reflected in increased NO bioactivity, the detail of mechanisms, for example the relative importance of up-regulation of mediators and antioxidant effects, is unclear. Optimum training schedules, possible sequential changes and the duration of benefit under various conditions also remain largely unresolved. In summary, epidemiological evidence strongly suggests that regular exercise confers beneficial effects on cardiovascular health. Shear stress-mediated improvement in endothelial function provides one plausible explanation for the cardioprotective benefits of exercise training.

Physical Activity and Cardiovascular Disease Prevention in Women: How Much Is Good Enough?

Epidemiologic data suggest that 30 min x d(-1) of brisk walking can reduce cardiovascular disease incidence in women and men. In a sedentary society, public health initiatives that promote moderate increases in physical activity may represent the optimal balance between efficacy, feasibility, and safety to achieve the desired cardioprotective effect.

Impact of walking upon medical care expenditure in Japan: the Ohsaki Cohort Study

BACKGROUND

Physical activity is expected to reduce medical costs by lowering the risk for a variety of chronic diseases. However, little is known about the actual magnitude of medical cost saved by physical activity. We attempted to quantify the association between time spent walking and medical care costs, based on a 4-year prospective observation of National Health Insurance (NHI) beneficiaries in rural Japan.

METHODS

In 27 431 Japanese men and women, aged 40-79 years, who had no functional limitation or conditions interfering with physical activity at the baseline survey in 1994, we ascertained all hospitalizations, outpatient visits, and the costs through computerized linkage with NHI claims history files between January 1995 and December 1998.

RESULTS

Medical costs significantly reduced with longer time spent walking. Per capita medical cost was pound 111.80 per month (95% CI: 109.3, 114.2) in those who walked for < or =30 minutes/day, pound 108.10 (95% CI: 105.7, 110.5) in those who walked for 30 minutes-1 hour, and pound 97.30 (95% CI: 95.5, 99.0) in those who walked for > or =1 hour, after multivariate adjustment of potential confounders.

CONCLUSIONS

This prospective study in Japan indicated that time spent walking was significantly associated with lower medical costs.

Physical activity and the prevention of cardiovascular disease

This article summarizes recent evidence on the role of physical activity in the prevention of overt and subclinical vascular disease. Epidemiologic data suggest that as little as 30 minutes per day of moderate-intensity physical activity, including brisk walking, reduces the incidence of clinical cardiovascular events in men and women. Regular exercise may also retard the progression of asymptomatic coronary and peripheral arteriosclerosis. Cardioprotective mechanisms of physical activity include reducing adiposity, blood pressure, diabetes incidence, dyslipidemia, and inflammation, and enhancing insulin sensitivity, glycemic control, fibrinolysis, and endothelial function. In a sedentary society such as the United States, public health initiatives that promote moderate increases in activity represent the optimal balance between efficacy and feasibility to achieve desired improvements in cardiovascular health.

Limits to the measurement of habitual physical activity by questionnaires

Despite extensive use over 40 years, physical activity questionnaires still show limited reliability and validity. Measurements have value in indicating conditions where an increase in physical activity would be beneficial and in monitoring changes in population activity. However, attempts at detailed interpretation in terms of exercise dosage and the extent of resulting health benefits seem premature. Such usage may become possible through the development of standardised instruments that will record the low intensity activities typical of sedentary societies, and will ascribe consistent biological meaning to terms such as light, moderate, and heavy exercise.

Age-related changes in risk factor effects on the incidence of thromboembolic and hemorrhagic stroke

We examined the changes in risk factor effects on the incidence of thromboembolic and hemorrhagic stroke as they may occur with age. Findings were based on repeated risk factor measurements at four examinations over a 26-year period in 7589 men in the Honolulu Heart Program. After each examination, 6 years of follow-up were available to assess risk factor effects on the incidence of stroke over a broad range of ages (45-93 years). As compared with normotensive men, the risk of thromboembolic stroke in the presence of hypertension declined from a 7-fold excess in men aged 45 to 54 years to a 1.4-fold excess in men aged > or =75 (P<.001). Adverse effects of diabetes and atrial fibrillation seemed to be equally important across all ages, whereas a protective effect of physical activity increased with age. Except for men with atrial fibrillation, the incidence of thromboembolic stroke increased significantly with age regardless of risk factor status, including men with normal blood pressure (P<.001). Although hemorrhagic events were less common, positive relations with cigarette smoking seemed to strengthen with age, whereas those with hypertension tended to decline. Our findings suggest that strategies for the prevention of stroke may need to account for changes in risk factor effects as they occur with age. Control of diabetes and the encouragement of active lifestyles in the elderly seem to be especially important.

It is never too late: change in physical activity fosters change in cardiovascular risk factors in middle-aged women

The purpose of the study was to determine the effect of physical activity, particularly change in physical activity over time, on cardiovascular risk factors in women. The 520 women in this analysis are part of an ongoing epidemiologic investigation of the effects of menopause on risk for cardiovascular disease; the investigation spans almost 20 years. The findings show that on average, physically active women have healthier risk factor profiles over time, and that as women change their activity level, their risk factor profiles change as well. Thus, for middle-aged women going through the menopausal transition, it is never too late to reduce their cardiovascular risk by increasing their activity level.

Cardiovascular risk factors, monitoring, and therapy for HIV-infected patients

Cardiovascular complications are important contributors to morbidity and mortality in HIV-infected patients. These complications can usually be detected at subclinical levels with monitoring, which can help guide targeted interventions. This article reviews available data on types and frequency of cardiovascular manifestations in HIV-infected patients and proposes monitoring strategies aimed at early subclinical detection. In particular, we recommend routine echocardiography for HIV-infected patients, even those with no evidence of cardiovascular disease. We also review preventive and therapeutic cardiovascular interventions. For procedures that have not been studied in HIV-infected patients, we extrapolate from evidence-based guidelines for the general population.

Periodontal management of patients with cardiovascular diseases

Periodontists are often called upon to provide periodontal therapy for patients with a variety of cardiovascular diseases. Safe and effective periodontal treatment requires a general understanding of the underlying cardiovascular diseases, their medical management, and necessary modifications to dental/periodontal therapy that may be required. In this informational paper more common cardiovascular disorders will be discussed and dental management considerations briefly described. This paper is intended for the use of periodontists and members of the dental profession.

Prevention of cardiovascular diseases. Coronary artery disease, congestive heart failure, and stroke

Cardiovascular disease leads to significant morbidity and mortality in the older population. Results of risk reduction can be dramatic in terms of patient survival and quality of life. This article reviews evidence for cardiovascular risk factors and disease prevention in older adults. Interventions which reduce morbidity and mortality from coronary artery disease, heart failure, and cerebrovascular disease in the elderly population are examined. Attention is given to the role of cardiovascular disease in older women and in minorities, subsets not well-represented in many studies.

Physical activity patterns among walkers and compliance with public health recommendations

PURPOSE

Walking is the most common leisure-time physical activity (LTPA) among U.S. adults. The purpose of this study was to estimate the prevalence of walking for physical activity and the proportion of walkers who met current public health physical activity recommendations.

METHODS

We analyzed data from the 1998 Behavioral Risk Factor Surveillance System, a collection of state-based, random-digit-dialed telephone surveys of adults. Physical activity measures included the type, frequency, and duration of the two LTPAs in which respondents engaged most often during the previous month. We calculated the prevalence of walking and the prevalence of three physical activity patterns defined by combinations of walking duration and frequency. We also examined the effect on these patterns of participating in a second LTPA.

RESULTS

In 1998, an estimated 38.6% of U.S. adults walked for physical activity. Among walkers, 21.3% walked a minimum of 30 min five or more times per week. This approximates compliance with current physical activity recommendations. Compliance increased to 34.5% when the criteria were relaxed to include at least 150 min of walking per week accumulated over three or more occasions. Relaxing the criteria further to include a minimum of 150 min.wk(-1) regardless of frequency produced only a small increase in compliance (37.6%). However, compliance with each of these three activity patterns approximately doubled when a second LTPA was taken into account.

CONCLUSIONS

Less than 40% of walkers complied through walking with even our most liberal physical activity pattern (> or =150 min.wk(-1) regardless of frequency). For walkers to meet current public health recommendations, many need to walk more frequently and/or to engage in additional physical activities.

Comparison of cardiorespiratory fitness versus leisure time physical activity as predictors of coronary events in men aged < or = 65 years and > 65 years

Both high peak oxygen consumption (VO(2)) and high levels of leisure time physical activity (LTPA) are associated with a reduced risk of cardiovascular morbidity and mortality. We examined the contributions of LTPA and peak VO(2) to the risk of coronary events (CEs) in healthy younger (< or = 65 years, n = 522) and older (>65 years, n = 167) men from the Baltimore Longitudinal Study of Aging. LTPA derived from self reports of time spent in 97 activities were converted into METs-minutes/24 hours and grouped into high (> or = 6 METs), moderate- (4 to 5.9 METs), and low-intensity LTPA (<4 METs). Cardiorespiratory fitness was determined by measuring peak VO(2) during a maximal treadmill exercise test. Over a mean follow-up of 13.4 +/- 6.3 years, CEs occurred in 63 men. After accounting for coronary risk factors, proportional-hazards analyses showed a relative CE risk of 0.53 (p <0.0001) for a SD increase in peak VO(2) in younger men and 0.61 (p = 0.024) in older men, whereas total LTPA was unrelated to coronary risk in either age group. When the 3 LTPA intensity levels were substituted for total LTPA in the model, peak VO(2) remained the only predictor of events in younger men, whereas high-intensity LTPA (RR = 0.39 for tertile 3 vs tertiles 1 and 2, p = 0.016) and peak VO(2) (RR = 0.61/SD increase, p = 0.024) were of similar importance in older men. Thus, in healthy younger men, higher cardiorespiratory fitness but not LTPA predicts a reduced risk of coronary heart disease, independent of conventional risk factors. For older men, high-intensity LTPA and fitness appear to be of similar importance in reducing coronary risk.

Screening for traditional risk factors for cardiovascular disease: a review for oral health care providers

BACKGROUND

Cardiovascular disease, or CVD, is associated with a very high rate of morbidity and mortality among people in the United States. Primary and secondary prevention measures will help reduce cardiovascular events and increase the overall health of the patient population.

METHODS

The author conducted MEDLINE and Internet searches and reviewed publications from professional organizations for the most up-to-date information on CVD and associated risk factors.

RESULTS

More than 450,000 articles and monographs on CVD were published in English between January 1990 and May 2001. Of these, approximately 45,000 discussed CVD and risk factors. The author selected and reviewed more than 550 publications on the basis of their relevance to epidemiology, etiology, and primary and secondary prevention of CVD.

CONCLUSIONS

Recent information regarding the pathogenesis and treatment of CVD suggests that oral health care providers can perform screening for risk factors and aid in monitoring of specific conditions that put people at an increased risk of developing and exacerbating existing CVD. Dentists need to take a proactive role in this endeavor.

CLINICAL IMPLICATIONS

As with most medical conditions, oral health care providers play an important function as it relates to the overall health of their patients. This article provides a timely update on CVD and the relationship between CVD and its risk factors, and offers suggestions for oral health care providers as to when they should interact with patients and patients' primary health care providers to possibly reduce the mortality and morbidity of CVD.

Exercise prescription for the elderly: current recommendations

The benefits for elderly individuals of regular participation in both cardiovascular and resistance-training programmes are great. Health benefits include a significant reduction in risk of coronary heart disease, diabetes mellitus and insulin resistance, hypertension and obesity as well as improvements in bone density, muscle mass, arterial compliance and energy metabolism. Additionally, increases in cardiovascular fitness (maximal oxygen consumption and endurance), muscle strength and overall functional capacity are forthcoming allowing elderly individuals to maintain their independence, increase levels of spontaneous physical activity and freely participate in activities associated with daily living. Taken together, these benefits associated with involvement in regular exercise can significantly improve the quality of life in elderly populations. It is noteworthy that the quality and quantity of exercise necessary to elicit important health benefits will differ from that needed to produce significant gains in fitness. This review describes the current recommendations for exercise prescriptions for the elderly for both cardiovascular and strength/resistance-training programmes. However, it must be noted that the benefits described are of little value if elderly individuals do not become involved in regular exercise regimens. Consequently, the major challenges facing healthcare professionals today concern: (i) the implementation of educational programmes designed to inform elderly individuals of the health and functional benefits associated with regular physical activity as well as how safe and effective such programmes can be; and (ii) design interventions that will both increase involvement in regular exercise as well as improve adherence and compliance to such programmes.

Cardiovascular monitoring and therapy for HIV-infected patients

Cardiovascular complications are important contributors to morbidity and mortality in HIV-infected patients. These complications can usually be detected at subclinical levels with monitoring, which can help guide targeted interventions. This article reviews available data on types and frequency of cardiovascular manifestations in HIV+ patients and proposes monitoring strategies aimed at early subclinical detection. In particular, we recommend routine echocardiography for HIV+ patients, even those with no evidence of cardiovascular disease. We also review preventive and therapeutic cardiovascular interventions. For procedures that have not been studied in HIV+ patients, we extrapolate from evidence-based guidelines for the general population.

High level of physical activity preserves the cardioprotective effect of preinfarction angina in elderly patients

OBJECTIVES

The study investigated the effects of physical activity on preinfarction angina, a clinical equivalent of ischemic preconditioning (PC), in adult and elderly patients with acute myocardial infarction (AMI).

BACKGROUND

Preinfarction angina seems to confer protection against in-hospital mortality in adult but not in elderly patients. However, it has been experimentally demonstrated that exercise training restores the protective effect of PC in the aging heart.

METHODS

We retrospectively verified whether physical activity preserved the protective effect of preinfarction angina against in-hospital mortality in 557 elderly patients with AMI. Physical activity was quantified according to the Physical Activity Scale for the Elderly (PASE).

RESULTS

In-hospital mortality was 22.2% in elderly patients with preinfarction angina and 27.2% in those without (p = 0.20). When the PASE score was stratified in quartiles (0 to 40, 41 to 56, 57 to 90, >90), a high score was strongly associated with reduced in-hospital mortality (30.8%, 32.2%, 17.2% and 15.3%, respectively, p < 0.001 for trend). Interestingly, a high level of physical activity reduced in-hospital mortality in elderly patients with preinfarction angina (35.7%, 35.4%, 12.3% and 4.23%, respectively, p < 0.001 for trend) but not in those without (23.0%, 27.2%, 26.0% and 35.0%, respectively, p = 0.35 for trend). Accordingly, the protective role of preinfarction angina on in-hospital mortality was present only in elderly patients showing a high level of physical activity (adjusted odds ratio, 0.09; 95% confidence interval, 0.01 to 0.57; p < 0.05).

CONCLUSIONS

Physical activity and not preinfarction angina protects against in-hospital mortality in elderly patients with myocardial infarction. Nevertheless, the protective effect of preinfarction angina is preserved in elderly patients with a high level of physical activity.

Dietary carbohydrates, physical inactivity, obesity, and the 'metabolic syndrome' as predictors of coronary heart disease

Several decades of epidemiological and clinical research have identified physical inactivity, excessive calorie consumption, and excess weight as common risk factors for both type 2 diabetes mellitus and coronary heart disease. This trio forms the environmental substrate for a now well-recognized metabolic phenotype called the insulin resistance syndrome. Recent data suggest that a high intake of rapidly absorbed carbohydrates, which is characterized by a high glycemic load (a measure of carbohydrate quality and quantity), may increase the risk of coronary heart disease by aggravating glucose intolerance and dyslipidemia. These data also suggest that individuals who are obese and insulin resistant are particularly prone to the adverse effects of a high dietary glycemic load. In addition, data continue to accumulate suggesting the important beneficial effects of physical activity, even at moderate levels, and weight reduction on improving insulin sensitivity and reducing the risk of coronary heart disease. Future metabolic studies should continue to quantify the physiological impact of different foods on serum glucose and insulin, and such information should routinely be incorporated into large-scale and long-term prospective studies, in which the possible interaction effects between diet and other metabolic determinants such as physical activity and obesity can be examined. Until more definitive data are available, replacing refined grain products and potatoes with minimally processed plant-based foods such as whole grains, fruits, and vegetables, and reducing the intake of high glycemic load beverages may offer a simple strategy for reducing the incidence of coronary heart disease.

Dose response between total volume of physical activity and health and fitness

PURPOSE

Studies published in 1990s were evaluated for the possible dose response between the total volume of physical activity and the fitness and health outcomes, and for the characteristics of the dose response relations.

METHODS

Nineteen observational studies and 15 randomized trials were identified. The scope of the studies was on primary prevention among inactive, healthy, middle-aged and elderly men and women. MET-min x wk(-1) was used as the primary volume measure. No studies addressing specifically the volume-outcome dose response were identified.

RESULTS

The cross-sectional and follow-up studies suggested a graded dose response of the volume of physical activity with all-cause mortality, stroke and several coronary heart disease risk factors. The benefits were apparent among both men and women. Nonrandomized and uncontrolled randomized trials exhibited no clear dose response relationship, whereas the randomized controlled trials showed a crude graded dose response between the exercise volume as measured by MET-min x wk(-1) and VO(2max) but not between volume and disease risk factors. An apparently clearer dose response was seen between the intensity of physical activity and the VO(2max) response. These data do not allow for quantitative characterization of the observed dose response relations between physical activity volume and health and fitness.

CONCLUSION

Fairly strong evidence indicates a crude dose response between the total volume of weekly physical activity and cardiorespiratory fitness but only weak evidence for a dose response of activity volume and health measurers.

Physical activity in the prevention of cardiovascular disease: an epidemiological perspective

This review of the epidemiological evidence regarding physical activity and cardiovascular disease (CVD) provides substantial evidence from many different populations that leisure time physical activity is associated with reduced risk of coronary heart disease (CHD) and cardiovascular mortality in both men and women and in middle-aged and older individuals. Physical activity appears to be a critical factor in both primary and secondary prevention of CHD. The studies indicate a dose-response relationship between overall physical activity and CVD, which is linear at least up to a certain level of activity. Prospective studies suggest that physical activity is also associated with reduced risk of stroke. The mechanisms underlying the protective effect of physical activity on CVD are still unclear. In recent years. the view that physical activity has to be vigorous to achieve a reduction in risk of CHD has been questioned. Overall, the evidence points to the benefit of continued regular moderate physical activity which does not need to be strenuous or prolonged and includes daily leisure activities such as walking or gardening which are readily attainable by large sections of the population. Taking up regular light or moderate physical activity in middle or older age confers significant benefit for CVD and all-cause mortality.

Prognostic value of treadmill exercise testing in elderly persons

BACKGROUND

Recent exercise testing guidelines recognized a gap in knowledge about the prognostic value of treadmill exercise testing in elderly persons.

OBJECTIVE

To test the hypothesis that treadmill exercise testing has equal prognostic value among elderly (> or =65 years of age) and younger (<65 years of age) persons and to examine the incremental value of this testing over clinical data.

DESIGN

Inception cohort with a median follow-up of 6 years.

SETTING

Olmsted County, Minnesota.

PATIENTS

All elderly (n = 514) and younger (n = 2593) residents of Olmsted County who underwent treadmill exercise testing between 1987 and 1989.

MEASUREMENTS

Overall mortality and cardiac events (cardiac death, nonfatal myocardial infarction, and congestive heart failure).

RESULTS

Compared with younger patients, elderly patients had more comorbid conditions, achieved a lower workload (6.0 and 10.7 metabolic equivalents; P < 0.001), and had a greater likelihood of a positive exercise electrocardiogram (28% and 9%; P < 0.001). With median follow-up of 6 years, overall survival (63% and 92%; P < 0.001) and cardiac event-free survival (66% and 95%; P < 0.001) were worse among elderly persons than among younger persons. Workload was the only treadmill exercise testing variable associated with all-cause mortality in both age groups, and the strength of association was similar. Workload and angina with exercise testing were associated with cardiac events in both age groups, whereas a positive exercise electrocardiogram was associated with cardiac events only in younger persons (P < 0.05 for all comparisons). After adjustment for clinical variables, workload was the only additional treadmill exercise testing variable that was predictive of death (P < 0.001) and cardiac events (P < 0.05); the strength of the association was similar in both age groups. Each 1-metabolic equivalent increase in exercise capacity was associated with a 14% and 18% reduction in cardiac events among younger and elderly persons, respectively.

CONCLUSIONS

In elderly persons, treadmill exercise testing provided prognostic information that is incremental to clinical data. After adjustment for clinical factors, work-load was the only treadmill exercise testing variable that was strongly associated with outcome, and its prognostic effect was of the same magnitude in elderly and younger persons.

Measurement of daily walking distance-questionnaire versus pedometer

PURPOSE

This study compared measurements of daily walking distance on the College Alumnus questionnaire (CAQ) and a pedometer.

METHODS

A total of 96 men and women (25-70 yr of age) with a wide range of physical activity habits were studied. Physical activity index was computed from the College Alumnus questionnaire (PAI-CAQ) as the sum of the energy expended in stair climbing, walking, and sports and recreational physical activity. Data on walking distance were compared with values obtained from the Yamax electronic pedometer (DW-500B). Participants wore the pedometer for 7 consecutive days, except when sleeping, showering, or performing sports and recreational activities.

RESULTS

Subjects underestimated their daily walking distance on the CAQ, compared with the pedometer (1.43 +/- 1.01 vs 4.17 +/- 1.61 km x d(-1)). The energy expended in walking was correspondingly lower on the CAQ, compared with the pedometer-derived values (555 +/- 405 versus 1608 +/- 640 kcal x wk(-1)).

CONCLUSIONS

These findings suggest that electronic pedometers are useful for examining questions about walking distance on physical activity questionnaires.