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We studied the adoption or maintenance of physical activity and other optional lifeway patterns for their influence on mortality rates of Harvard College alumni. Men aged 45-84 in 1977, surveyed by questionnaire in 1962 or 1966 and again in 1977, were followed from 1977 through 1988 or to age 90. Of 14,786 alumni, 2,343 died in 165,402 man-years of follow-up. Relative risks of death, standardized for potential confounding influences, for men who between questionnaires increased their physical activity through walking, stair climbing, and sports or recreational activities to 1,500 kcal or more per wk were 0.72 (95% confidence interval 0.64-0.82), compared with 1.00 for men who remained less active. Corresponding relative risks for men who adopted moderately vigorous sports play (> or = 4.5 METs) were 0.73 (0.65-0.81) vs 1.00 for men not adopting such sports; and for cigarette smokers who quit, 0.74 (0.65-0.84) vs 1.00 for persistent smokers. Men with recently diagnosed hypertension had a lower death risk than long-term hypertensives (0.80; 0.70-0.92), as did men with consistent normotension (0.52; 0.47-0.58). Changes in body-mass index had little influence on mortality during follow-up. These findings fit the hypothesis that adopting a physically active lifeway, quitting cigarette smoking, and remaining normotensive independently delay all-cause mortality and extend longevity.

Background: Recent trends toward increasing physical exercise, stopping cigarette smoking, and avoiding obesity may increase longevity. We analyzed changes in the lifestyles of Harvard College alumni and the associations of these changes with mortality., Methods: Men who were 45 to 84 years of age in 1977 and who had reported no life-threatening disease on questionnaires completed in 1962 or 1966 and again in 1977 were classified according to changes in lifestyle characteristics between the first and second questionnaires. We analyzed changes in their level of physical activity, cigarette smoking, blood pressure, and body weight, and the relation of these factors to mortality between 1977 and 1985., Results: Of the 10,269 men, 476 died during this period (which totaled 90,650 man-years of observation). Beginning moderately vigorous sports activity (at an intensity of 4.5 or more metabolic equivalents) was associated with a 23 percent lower risk of death (95 percent confidence interval, 4 to 42 percent; P = 0.015) than not taking up moderately vigorous sports. Quitting cigarette smoking was associated with a 41 percent lower risk (95 percent confidence interval, 20 to 57 percent; P = 0.001) than continuing smoking, but with a 23 percent higher risk than constant nonsmoking. Men with recently diagnosed hypertension had a lower risk of death than those with long-term hypertension (relative risk, 0.75; 95 percent confidence interval, 0.55 to 1.02; P = 0.057), as did men with consistently normal blood pressure (relative risk, 0.52; 95 percent confidence interval, 0.40 to 0.68; P < 0.001). Maintenance of lean body mass was associated with a lower mortality rate than long-term, recent, or previous obesity. The associations between changes in lifestyle and mortality were independent and were largely undiminished by age. Our findings on death from coronary heart disease mirrored those on death from all causes., Conclusions: Beginning moderately vigorous sports activity, quitting cigarette smoking, maintaining normal blood pressure, and avoiding obesity were separately associated with lower rates of death from all causes and from coronary heart disease among middle-aged and older men.

For physical activity surveys that would identify relations to chronic diseases, quality of life, and longevity, the method of choice remains the questionnaire, especially if it can be standardized and administered in uniform fashion to large populations. A sample questionnaire derived largely from epidemiological experience with the Harvard Alumni Health Study is presented that requests anthropometric estimates; physician-diagnosed diseases by year of onset; contemporary physical activities including walking, stair-climbing, and recreational pursuits; food-frequency data that estimate nutrient values and caloric intakes; and social habits affecting health. The questionnaire presents opportunities for cross-sectional, retrospective, and prospective studies. Personal characteristics, physical activities, and other elements of lifestyle may be used as predictor or outcome variables in testing specific hypotheses. Representative surveys are described that have validated and used questionnaires of various complexities, some complemented by measures of physiological fitness. The epidemiological survey questionnaire, when properly designed and administered, can measure effectively energy intake, energy retention, energy expenditure, physiological fitness, quality of life, and health maintenance.

We examined patterns of physical activity and other characteristics that might deter hypertension or delay all-cause mortality among university alumni, 1962-1985. Collegiate sports play did not alter hypertension incidence, nor did contemporary walking, stair-climbing, or light sports play among 5463 University of Pennsylvania alumni, 739 of whom developed hypertension. But vigorous sports play reduced hypertension incidence; and overweight, gain in weight, history of parental hypertension, or any combination of these, increased it. Among 819 hypertensive Pennsylvania alumni (138 died during follow-up), vigorous sports play had minimal influence on mortality; but freedom from overweight and cigarette smoking deferred death. Among 16,936 Harvard College alumni, of whom 2614 died during follow-up, lack of vigorous sports play, or presence of hypertension, cigarette smoking, and overweight increased risk of premature mortality, heightened by any combination of these adverse characteristics. Overall, we found an inverse relationship between vigorous sports participation and hypertension risk but a direct relationship between risk and weight-for-height, weight gain, or parental hypertension. With regard to all-cause mortality, cigarette smoking and hypertension were most hazardous for the individual; smoking and lack of vigorous recreational play were most hazardous for the alumnus population as a whole.

Longitudinal study of 16,936 Harvard alumni, followed for life-style experiences as related to cardiovascular disease (CVD) and longevity, identified 572 first coronary heart disease (CHD) attacks, 1962-1972, and 1,413 all-cause deaths, 1962-1978. Men expending 8.4+ MJ (2,000+ kcal) per week in walking, stair-climbing, and sports play were at 39% lower risk of developing CHD than less active classmates. Attributable risk estimates suggested: there might have been 16% fewer CVD deaths in the alumni population if every man had exercised 8.4+ MJ per week; 25% fewer from total cigarette abstinence; 9% fewer from abolition of hypertension; 6% fewer with less obesity; and 11% fewer CVD deaths in the absence of parental CHD. Discounting the influence of blood pressure status, cigarette habit, net weight gain since college, and parental history of early death, the more active alumni (39% of the population) are estimated to have lived on average one and one-quarter years longer than less active men.

We examined the physical activity and other life-style characteristics of 16,936 Harvard alumni, aged 35 to 74, for relations to rates of mortality from all causes and for influences on length of life. A total of 1413 alumni died during 12 to 16 years of follow-up (1962 to 1978). Exercise reported as walking, stair climbing, and sports play related inversely to total mortality, primarily to death due to cardiovascular or respiratory causes. Death rates declined steadily as energy expended on such activity increased from less than 500 to 3500 kcal per week, beyond which rates increased slightly. Rates were one quarter to one third lower among alumni expending 2000 or more kcal during exercise per week than among less active men. With or without consideration of hypertension, cigarette smoking, extremes or gains in body weight, or early parental death, alumni mortality rates were significantly lower among the physically active. Relative risks of death for individuals were highest among cigarette smokers and men with hypertension, and attributable risks in the community were highest among smokers and sedentary men. By the age of 80, the amount of additional life attributable to adequate exercise, as compared with sedentariness, was one to more than two years.

Several studies are reviewed that examine the role of exercise in men at work and in men at leisure activity and sports play. All show that adequate exercise reduces the risk of coronary heart disease. Many recent investigations have undertaken the study of the various mechanisms by which physical activity produces these effects.

Epidemiologic studies in Olympic year 1984 suggest that personal athleticism alters trends in life-style and coronary heart disease. Analysis of 572 first attacks among 16,936 Harvard alumni, 1962 to 1972, and 1,413 total deaths, 1962 to 1978, shows that habitual postcollege exercise, not student sports play, predicts low coronary heart disease risk. Sedentary alumni, even ex-varsity athletes, have high risk. Sedentary students becoming physically active alumni acquire low risk. Exercise benefit is independent of contrary life-style elements--smoking, obesity, weight gain, hypertension, and adverse parental disease history--in affecting coronary heart disease incidence. Hypertension is clinically the strongest predictor of coronary attack, but inadequate exercise is strongest on a community basis. Exercise level is inversely related to total, cardiovascular, and respiratory mortality but less related to cancer or unnatural deaths. The current exercise revolution may improve life-style, cardiovascular health, and longevity.

From the college entrance health data of 50,000 male former students, the records of 45 who eventually died of Hodgkin's disease were compared with those of 180 surviving classmates with reference to certain indicator characteristics. Risk ratios of Hodgkin's disease tended to be lower for men who had experienced various common contagious diseases in childhood. This reduced incidence of clinical contagions may signify that: 1) Inadequate early challenge of immune mechanisms left subjects more susceptible to later Hodgkin's disease, whether or not it is of infectious origin; 2) heightened immune mechanisms that led to subclinical attacks of early contagious diseases promoted an autoimmune response that evolved as Hodgkin's disease; or 3) early childhood infections eliminated some subjects who otherwise would have attended college and ultimately developed adult-onset Hodgkin's disease. Also, Hodgkin's disease risk was higher for students who had reported early death of a parent, particularly from cancer. Moreover, the risk tended to be increased among collegians who were obese, heavy cigarette smokers, and coffee drinkers. None of these indicator characteristics was associated with 89 fatal lymphomas of other types that occurred in the same study population.

Epidemiological studies have left no doubt as to the existence of a strong inverse relationship between physical exercise and coronary heart disease (CHD) risk. British studies of transport workers and civil servants, together with American studies of stevedores and college alumni, have provided persuasive evidence that contemporary vigorous activity is accompanied by lower risk of both fatal and nonfatal CHD. The relationship is largely independent of influential characteristics of high risk such as cigarette smoking, hypertension, obesity, and family history of hypertensive--atherosclerotic disease. Recent studies of occupational or leisure physical exercise among residents of Framingham, Massachusetts, the state of Iowa, four residential areas of Holland, urban--rural sections of Puerto Rico, Seattle--King County, Washington, city employees in Los Angeles, and various regions of Finland and Norway support the likelihood that the inverse relationship of exercise and CHD is causal, signifying a protective effect of exercise rather than an incidental contrast due to a selective influence of precursive CHD symptoms. Experimental studies in monkeys have added laboratory evidence that endurance exercise inhibits the development of CHD. The questions we need to address are not whether exercise is a real element for cardiovascular health, but what kind of exercise is needed, and how much, i.e., with what frequency, intensity, timing, and duration. An understanding of the ways and means by which exercise alters CHD risk is only beginning to emerge, but there is wide acceptance that its benefits are vitally needed in the sedentary Western world.

That cigarette smoking is causally associated with development of cardiovascular disease is recognized unequivocally. Epidemiological studies worldwide have documented the many pathways of influence and synergism by which this ubiquitous but artificial habit exerts its ill effects on cardiorespiratory and other body systems, leading not only to cardiovascular disease but to cancer and other ailments. Current investigations among college alumni, women, elderly, and other subgroups provide data on how various independent influences combine with smoking to establish risk and promote pathogenesis of cardiovascular disease. Their findings also confirm that cigarette smoking is one of the strongest instigators. All of this knowledge has implications for the design and implementation of effective intervention programmes.