The control of cardiovascular risk factors in the elderly

PREVENTIVE

MEDICINE

The Control

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3247 (1976)

of Cardiovascular

Risk Factors

in the Elderly

J. H. ABRAMSON’ AND C. HOPP’ Department of Social Medicine, Hebrew University-Hadassah Medical School and Hadassah Vniversi@ Hospital, Jerusalem, Israel and Brookdale Institute of Gerontology and Adult Human Development in Israel (American Joint Distribution Committee) Although measures to prevent cardiovascular diseases should preferably be started early in the life span, epidemiological evidence and the limited available results of trials suggest that the control of cardiovascular risk factors is of value even in later adult life. Such intervention may be expected to have a greater absolute short-term effect on the burden of these diseases than similar intervention among younger people, in spite of its smaller impact on the individuals risk. The specific measures which are probably of value among the elderly include blood pressure and weight control, the stopping of cigarette smoking, and (with less certainty) the control of blood lipids and the encouragement of physical activity. The practical implementation of these measures at individual, family, and local community levels is probably best achieved within the ordinary primary health care system. An illustrative community program in Jerusalem is described, in which the control of multiple risk factors is undertaken as an integral and central function of a family practice.

It is among the elderly that coronary and hypertensive heart disease and cerebrovascular and peripheral vascular disorders reach their peaks of incidence, prevalence, and mortality. Since the pathogenesis of these diseases is long-term, even lifelong (87), it is clear that available preventive measures should preferably be applied early in the life span. But this does not necessarily mean that such measures are worthless once later adult life has been reached. The main purpose of this review is to examine evidence bearing on this question. Intensive research, especially in populations with a high prevalence of these diseases, has identified a number of characteristics associated with an increased susceptibility to cardiovascular diseases or their effects. There is much information on inter-relationships among these risk factors and on the impact of their combinations in various populations (85). Although mechanisms of action are far from fully understood (65) there are strong indications that measures to modify certain risk factors can reduce the incidence of cardiovascular diseases and their complications. The direct evidence for the effectiveness of such measures in the elderly is very

’ Department of Social Medicine, Hebrew University-Hadassah Medical School and Hadassah University Hospital, P.O. Box 1172, Jerusalem, Israel; and Brookdale Institute of Gerontology and Adult Human Development in Israel (American Joint Distribution Committee). 2 Department of Social Medicine, Hebrew University-Hadassah Medical School and Hadassah University Hospital. 32 Copyright AI1 rights

@ 1976 by Academic Press. Inc. of reprodnction in any form resewed.

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limited. Conclusions based on studies of young or middle-aged adults are not necessarily applicable to older people, for a number of reasons. First, older persons have a higher prevalence of clinical cardiovascular disease; after the development of clinical disease the further prognosis is affected by new risk factors, such as the presence of myocardial damage. Secondly, the elderly have more marked subclinical pathological changes, which may be impossible or difficult to reverse. The relative importance of specific risk factors, which act at different stages of the pathogenetic process, thus varies with age (46). Thirdly, by the time older adulthood is reached there has been ample time for selective factors to operate. People who are then still free of clinical disease may owe this partly to a relatively low susceptibility to the effects of the risk factors to which they have been exposed, and those who are still alive despite clinical disease may owe their survival, in part, to the same reason. The value of preventive measures may also be influenced by age-related or cohort-related differences in biological attributes, in the flexibility of habits, and other circumstances. The above considerations suggest that preventive measures may have less effect among the elderly. There is, however, an important encouraging aspect, at least with respect to short-term benefits: because of the relatively high rates of incidence and mortality among the elderly, the absolute impact of a preventive measure within a given time may be greater than in a younger age group, even if the effect on the individual’s risk is smaller. A 10% reduction of mortality in a population of older people may save more lives in a year than a 50% reduction in the same number of younger people. We will first review the value of specific measures aimed at the control of risk factors, drawing on epidemiological evidence and, when available, the results of trials. We will then discuss practical implementation and describe aspects of an illustrative program conducted in Jerusalem. PREVENTIVE

MEASURES

Reduction of Blood Pressure Hypertension is a powerful independent risk factor for cerebrovascular disease, congestive heart failure, and other cardiovascular diseases, including coronary heart disease in populations where the latter condition is common (85). A rise in blood pressure with age does not occur in all individuals or even in all populations (44) and cannot be regarded as a “normal” phenomenon. Prospective studies have showed that a raised pressure is a definite hazard even at a late age. Among the elderly, the risk of stroke (55,72,80) and coronary heart disease (34) and the risk of death (82) rise progressively with increasing systolic or diastolic pressures. Controlled trials have shown that hypotensive treatment produces a striking reduction in the risk of cardiovascular diseases (39,91,92,95). There is a marked effect on the occurrence of cerebrovascular accidents and congestive heart failure, as well as of renal and retinal complications. On the other hand, most trials have shown little or no effect on the incidence of coronary complications. The combined results of a number of studies (4, 5, 12, 39,45, 47, 91, 92, 95) indicate that the risk of coronary mortality among treated hypertensives is about 0.7 times that among untreated cases; this is a weighted average (67) of the relative risks in

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these trials. Including the nonfatal myocardial infarctions reported in some of these studies, the relative risk becomes 0.8. Since these figures do not differ significantly from unity (P = 0.18 and 0.25, respectively) an effect on coronary complications must be regarded as “not proven,” although it cannot be ruled out. Both strokes and congestive cardiac failure (66) have a high incidence among the elderly, among whom there thus seems little reason to doubt the value of blood pressure control. This is confirmed by the limited direct information available. In the well-known randomized trials conducted by the Veterans Administration in the United States, which included World War I veterans (30), treatment is reported to have been as effective in men over 60 years old as in younger men (32). In the first of these trials (diastolic pressures of 115-129 mm Hg) there were eight severe complications or deaths among placebo-treated men aged 65+ years, as against only one among treated men of this age (91). In the second trial (diastolic pressures of 90-114 mm Hg) no specific findings were published for the elderly, but the proportion of morbid events prevented was similar below and above the age of 50 years (92). The number of complications prevented per 100 persons treated was higher in the older age group (70). While more trials in the aging and aged are needed, there seems at present to be no reason to deprive elderly people of the probable benefit of hypotensive treatment. There is apparently little basis for the fear that if cerebrovascular disease is present hypotensive treatment may cause harm, even a stroke, by impairing the cerebral blood flow. If this danger exists it is probably outweighed by the benefits of treatment (55); a cautious reduction of blood pressure is very unlikely to produce the complications occasionally observed after a sudden profound drop in pressure (9). Hypotensive therapy appears to be safe even for those who have already had a stroke, among whom it reduces the risk of congestive heart failure and (at least in some categories of patients) the risk of further strokes (5, 12,47). Among the elderly, as at younger ages, the increase in risk of death or disease associated with a higher blood pressure is manifest even over pressure ranges considerably lower than those usually regarded as abnormally high (34,55,72,80, 82). This clearly points to the probable value of therapy even in mild hypertension, despite the absence of clear proof from controlled trials; it has been pointed out that the “mild” hypertensives studied in the second of the Veterans Administration trials (92) were not as mildly affected as they appeared, since their average diastolic pressures were at least 90 mm Hg (fifth phase) under basal or near-basal conditions (81), and they had a higher morbidity than would have been found among unselected patients with similar pressures (43). Accepting the epidemiological evidence that the treatment of mild hypertension may be beneficial, the choice of “critical levels” warranting therapy is to an extent arbitrary. Levels of 160 (systolic) and 95 (diastolic), for example, have been proposed on the grounds that they indicate a more than triple risk of both strokes and coronary heart disease (55). Slightly raised pressures are more common and less hazardous than higher ones, and the benefit of treatment, in both absolute and relative terms, is smaller in less severe hypertension (92). Hence, the lower the levels chosen, the greater the work load, without a proportionate rise in benefits. The choice of criteria for treatment thus depends largely on considerations of

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feasibility. One suggested solution is to limit the treatment of mild hypertension to cases who have additional defined risk markers (31). This approach finds its rationale in epidemiological findings such as those in an elderly population in Cook County, Illinois, where the risk of strokes was associated with blood pressure only among persons who already had clinical evidence of cardiovascular or certain other disorders (71). The need for treatment should not be determined only by the diastolic pressure. Pathophysiological considerations suggest that the systolic pressure may be a more important factor in the production of left ventricular hypertrophy, congestive heart failure, and cerebral hemorrhage (61). Solely systolic hypertension is not uncommon in the elderly, among whom it has been found to be associated with an increased risk of cardiovascular disease (16). In the Cook County study, the risk of strokes among persons aged 65-74 years with diastolic pressures below 80 mm Hg was strongly associated with the systolic pressure (80). There thus seems to be no justification for not treating solely systolic hypertension. There is a clear need, however, for controlled trials. One question which such trials must answer is whether in the presence of atherosclerosis it is safe to bring the systolic pressure down to a “normal” level if this means producing diastolic hypotension (61). Stopping Cigarette Smoking There is now a large body of evidence suggesting that even at a late age cigarette smoking is hazardous and better given up. Large-scale prospective studies have shown that male and female smokers aged 65-74 and 7584 years have higher mortality rates than nonsmokers, the rates rising with the number of cigarettes smoked (40,50). Although the mortality ratios of smokers (their death rates divided by those of nonsmokers) are considerably lower among older persons, the absolute difference in death rates between smokers and nonsmokers is greater at higher ages (50). The life expectancy of men smoking cigarettes at the age of 65 is 3 years less than that of nonsmokers (41). Well over half the excess mortality of cigarette smokers in the United States (among the elderly as well as among younger adults) is due to cardiovascular diseases (50) and there is now much evidence that cigarette smoking is a risk factor for the development of coronary heart disease, car pulmonale, peripheral vascular disease, and possibly cerebrovascular disease, independent of and additive to such other major risk factors as hypertension and hypercholesterolemia (73-75, 85). Although in the Framingham study (34) no independent association was found between smoking and coronary incidence above the age of 64, two large prospective studies in the United States have demonstrated that even at 75-84 years of age the death rate from coronary heart disease is slightly higher among cigarette smokers than among nonsmokers. The difference in mortality from cerebrovascular disease persisted to 65-74 years in one of these studies and to 75- 84 years in the other (40,50). In Doll and Hill’s study of British doctors, a difference in coronary mortality was found up to the age of 74 years (24). These and other studies have shown that the cardiovascular risk attached to smoking decreases with age. There have been no controlled studies of the effects on cardiovascular diseases of intervention to reduce smoking, although one such trial is at present in progress

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in Britain (76). The case for stopping smoking is largely based on survey findings, which have shown relatively low cardiovascular and other incidence and mortality rates among people who have given up smoking cigarettes, as compared with those continuing to smoke. Highly suggestive evidence has come from prospective studies in the United States, which have shown a reduced subsequent incidence of coronary events among middle-aged men who give up smoking, not attributable to associated differences in other risk factors (37, 49, 85). Also, a study of British doctors has shown that during a period when cigarette smoking declined significantly among physicians in comparison with the general population, the coronary death rate decreased among doctors while it rose in the total population (25). This difference was apparent over the 35-64 year age span; when the 35-84 year age span was considered there was a rise among doctors also, but far less marked than that in the general population. There is limited evidence concerning the effects of giving up cigarettes late in life. The two large prospective studies of mortality and smoking in the United States showed that the overall death rate at 65-74 years was lower among men who had given up smoking some years previously than among those who continued to smoke. This difference was clearly apparent if smoking had been discontinued at least 5-9 (40) or 10-14 (50) years previously. At higher ages (where many rates are not given because of small numbers) the findings were inconsistent (40). In one of these studies, relatively low rates of coronary mortality were found at 65-69 years even among men who had ceased smoking only l-4 years previously; at older ages (where many rates are not given) there was no clear evidence of a difference between exsmokers and smokers (40). In the other study, there was a clearly lower coronary mortality only among those who had ceased at least 15 years previously (50). In the Framingham study (37), men who ceased smoking after entering the study had a far lower risk of subsequent first coronary attacks than men who continued smoking, an effect which could not be ascribed to associated differences in other major risk factors. But this difference in coronary risk was apparent only up to the age of 64 years (as mentioned above, the Framingham study showed no association between smoking and coronary incidence above the age of 64). At 65-74 years the overall death-rate, however, was considerably lower among those who had given up smoking. There appears to be adequate justification for advising elderly cigarette-smokers to give this habit up, whether or not this reduces the specific risk of coronary disease. Reduction of Serum Lipids There is abundant epidemiological evidence that raised serum lipid levels indicate an increased risk of atherosclerotic diseases (85). The Framingham study, for example, has demonstrated relationships in both sexes between the serum cholesterol level and the risk of coronary heart disease, atherothrombotic brain infarction, and intermittent claudication (34). Encouraging results have also been reported in a number of trials of lipid-lowering diets (mainly characterized by a reduced intake of saturated fats and cholesterol) in the primary prevention of atherosclerotic diseases (22,68,77,84). Each of these trials presents methodological problems (17), and none is itself conclusive, but together they present a

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persuasive picture of favorable effects on the incidence of or mortality from coronary complications and, in one instance (22), cerebral infarction. These effects were found among men and in one study (68), but with less certainty, among women. The relevance of these findings to the care of the elderly, however, is open to question. Relationships between lipid levels and the incidence of atherosclerotic diseases are strongest in younger adult life, and they decrease with advancing age. In Framingham, the relationships between serum cholesterol and coronary, cerebrovascular, and peripheral arterial disease were no longer apparent above the age of 65 years among men, although among women the association with coronary heart disease remained apparent at 65-74 years (34,38). In the Kaiser-Permanente study the relationship between cholesterol level and subsequent myocardial infarction was less marked at higher ages among men, and was absent among women aged 65 years and over (33). No significant associations with serum cholesterol levels were found in prospective studies of strokes among persons aged 50-69 years in Birmingham, Alabama (72) or among those aged 65-74 in Cook County, Illinois (71). The preventive trials listed above were all conducted among middle-aged persons, except for one (combined primary and secondary prevention) performed among men aged 54-88 in Los Angeles. In this trial “most of the prophylactic effect occurred in the younger half of the study population, less than 65.5 years old at the start of the study,” although the older men exhibited a more marked drop in serum cholesterol levels (22). When clinical coronary heart disease has already developed, the evidence for an association between serum lipids and the long-term prognosis is inconsistent. Among a large group of men aged 30-64 years in the United States (the control group in a trial of lipid-lowering drugs), lipid levels some months after the infarction were among the many factors predictive of subsequent 3-year survival, but their independent contribution to this prediction was small (18). In the HIP study in New York, a relationship between serum cholesterol 6 months after a first infarction or a first diagnosis of angina pectoris and survival during the next 441 years was found among women aged 25-54 and 55-64 years, but not among men (93). Among male survivors of myocardial infarction in Oslo, a relationship with mortality from coronary heart disease during an 1l-year period was found among those initially aged 30-59 years, but not among those aged 60-67 years (63). No association with IO-year survival was found in a study of “good risk” Canadian veterans aged 31-83 years (78). Secondary prevention trials of the value of serum-lipid reduction in persons with established clinical disease have yielded inconsistent findings. In Scotland and in Newcastle the long-term use of clofibrate was found to produce a significant reduction of mortality among men and women with angina pectoris, whether alone or together with a history of myocardial infarction. There was no evidence, however, that this was due specifically to the drug’s lipid-lowering effect 123). In the United States, a large trial of clofibrate and other lipid-lowering drugs has demonstrated no reduction of late mortality in men after myocardial infarction, including those with an associated angina (19); it has been suggested that this may be because the mean decrease in serum cholesterol was small (%). Persons aged

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over 69 years were excluded from the first of the above trials, and those over 64 years from the other two. Secondary prevention trials of lipid-lowering diets have not all shown favorable effects (22) but on balance they indicate that such diets probably do yield small benefits (21). Most of these trials were conducted on middle-aged men. The limited evidence suggests that the efficacy of such diets decreases with increasing age. In a study in New Jersey which showed a reduced incidence of myocardial reinfarction, this effect was less striking among men aged 45-54 than among those aged 30-44 years (6). In a study in Oslo, a lipid-lowering diet produced a significant reduction of coronary relapses over a 5-year period among men aged 3&59 years, but a smaller and nonsignificant reduction among men aged 60-67 years (62).

It can hardly be claimed that the case for the control of serum lipid levels in the elderly is a strong one, at least in populations with high levels throughout the middle years. Possibly the best arguments for such control, especially by dietary means, are (a) that there is a possibility that it may be helpful to some older people, who should be given the benefit of this doubt; (b) that lipid-lowering diets, unlike lipid-lowering drugs (19), are not known to have harmful side-effects (27); and (c) that in a community program aiming at dietary modifications in younger persons it is difftcult to exclude the elderly, especially since dietary changes are best effected at a family level. Control of Weight The case for weight control is exemplified by the findings of the Framingham study (3,36,5 1,54), which has shown relationships in both sexes between a higher relative weight and the risks of congestive heart failure, atherothrombotic brain infarction and, more weakly, coronary heart disease. Overweight was associated with strikingly higher risks of sudden death and angina pectoris, but with only a slightly increased risk of myocardial infarction. There were strong associations with blood pressure in both sexes, and a weaker one with serum cholesterol among men. Overweight persons had a raised risk of subsequent hypertension. Much of the relationship with cardiovascular diseases could be accounted for by the role of blood pressure, serum cholesterol, and other associated characteristics; but there was some evidence that relative weight played an additional role, independent of these other hazards. Prospective studies in the United States provide limited evidence of relationships between relative weight and cardiovascular disease among the elderly. In one large sample (42) a clear relationship with coronary mortality was apparent among men and women aged 60-69 years (only among those with no history of previous hypertension), and a weaker one at 70-79 years. These associations were far less striking than among younger adults. There was also an increased risk of death due to nonsyphilitic aortic aneurysm (among men aged 50-69 years) and stroke (at 60-69 years, but not at 70-79 years). A study of people aged 65-74 years in Cook County, Illinois, showed an association with an increased risk of stroke, but only among those with previous clinical evidence of cardiovascular disease (71). In Birmingham, Alabama, no relationship with strokes was found among persons aged 50-69 (72).

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Some experts (58,59) have minimized the importance of overweight and adiposity in relation to coronary heart disease, on two main grounds. First, relationships with this disease, especially with myocardial infarction and fatal events, are not apparent in all populations (26, 59)-it has been pointed out that “it almost certainly matters more by which dietary pathway you become fat, than whether you become fat” (79). Secondly, there is little evidence that relative weight and fatness are independent predictors of the risk of coronary heart disease when the effects of blood pressure and cholesterol are taken into account. These arguments do not negate the possible value of efforts to avoid and remedy overweight in populations where an association with cardiovascular diseases exists. Even if the effect of overweight or adiposity (or of the nutritional or metabolic patterns indicated by their presence) is indeed mediated solely or mainly through the action of other risk factors, weight control may favorably modify or prevent the development of these other hazards. There have been no controlled studies of weight control in the prevention of cardiovascular diseases, although this measure has been included as a component in some successful trials of lipid-lowering diets (6, 77) and multiple preventive measures (84). Suggestive evidence of its value comes from clinical studies which have shown that weight reduction lowers blood pressure in a considerable proportion of overweight hypertensive patients (14), and from epidemiological observations. In the Framingham study it was found that changes in weight tended to be mirrored, especially in men, by changes in blood pressure, serum cholesterol and, less strikingly, blood glucose (3); these relationships did not vary with age over the 3 l-64 year range. During a period of severe food shortage in Russia, Holland, and Germany during World War II, a marked transient reduction was observed in the incidence of hypertension and hypertensive complications; there was a high prevalence of hypotension among prisoners of war (11). Among insured men in the United States, those who were rated for overweight and then became eligible for standard insurance because they reduced their weight had a considerably lower subsequent mortality than men who stayed overweight; this applied both to men aged 15-39 when issued with insurance and to those aged 40-69 (82). Among the elderly, it may be hoped that weight control will favorably affect the incidence of congestive heart failure and strokes, if only as a result of its influence on blood pressure. It is also possible that weight control may lower the risk of angina and reduce or delay sudden death, a frequent phenomenon in this age group (7, 15). The Framingham study revealed strong relationships between overweight and both these manifestations, possibly mediated through effects of obesity on the cardiac work load and on exercise tolerance (54). Encouragement of Physical Activity Although the findings are far from consistent, there is increasing evidence of a relationship between sedentary or inactive occupational activity and a high risk of coronary heart disease incidence and mortality (85). Of more direct relevance to prevention, there are also indications that vigorous leisure-time activity has a protective effect (13,29,69). A large prospective study of men and women in the United States (with no prior history of heart disease or stroke) has shown strong

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inverse relationships between mortality from coronary disease and stroke over a 6-year period and the amount of activity initially reported in answer to the question “How much exercise do you get (work or play)?” These relationships, which could not be explanted by associated differences in smoking habits, relative weight, or reported hypertension, were considerably more marked at 60-69 and 70-79 years than at lower ages (42). Of especial interest is a recent survey of British civil servants in physically inactive occupations, which suggested that vigorous leisure-time activity was protective against rapidly fatal heart attacks and other first attacks of coronary heart disease (69). This apparent effect could not be ascribed to associated differences in weight or smoking habits, and it showed little decline with age over the 40-64 year range. The effect was limited to high-intensity exercise, suggesting a need to reach a “threshold” level of activity sufftciently strenuous to have a “training” effect on the cardiovascular system. Available data indicate that such activity for brief periods several times a week enhances cardiopulmonary fitness (20, 8% although it is not without its hazards for previously inactive persons. Pending controlled trials, there is at least a prima facie case for the promotion of vigorous activity when this can be safely recommended, among the elderly (64) as among younger persons. “The immediate problem,” it has been suggested, “is not so much that of acquiring more evidence, but rather of motivating men and women of all ages to undertake regular vigorous exercise, and to enjoy it” (88). Treatment of Diabetes Diabetes mellitus is a well-established risk factor for coronary, cerebrovascular, and peripheral vascular disease, at all ages. These conditions tend to occur earlier and more frequently, and to be more severe, among diabetics. There is also increasing evidence that not only clinical diabetes, but the far more common phenomenon of impaired glucose tolerance (“asymptomatic hyperglycemia,” “chemical diabetes”) may be a risk factor for atherosclerotic disease (85). In clinical diabetes, especially its common maturity-onset form, it is unfortunately not certain that the control of hyperglycemia reduces the risk of atherosclerotic complications (85). Such an effect has been thrown in strong doubt by the findings of the University Group Diabetes Program in the United States (90, 91). Cardiovascular mortality in this long-term trial was no higher among diabetics in the placebo group, whose only active treatment was to be placed on a diet designed to control their weight, than among those also given oral hypoglycemic agents or insulin. The oral agents tested seemed in fact to be harmful in this respect. The value of treatment for asymptomatic hyperglycemia is still under investigation (76). Other Measures We will not review other preventive measures, on the grounds that either their value is not yet certain, or they are applicable to relatively small numbers of people or require highly specialized skills or elaborate facilities., Such measures include a reduced consumption of sugar (2) or coffee (53), the avoidance of stressful situations and the reduction of emotional stress, the administration to myocardial infarction survivors of aspirin (10, 28) or beta-blockers (1, 94), the treatment

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of hyperuricemia, hypothyroidism, and renal lesions, and the provision of prompt intensive care after acute heart attacks. PRACTICAL IMPLEMENTATION Although definitive proof from large-scale controlled trials (8) is not yet available, the evidence suggesting that the control of multiple risk factors can achieve a considerable reduction in common cardiovascular diseases is now sufftciently strong to warrant urgent implementation (85, 88). The multiple risk factor approach finds its logical basis in evidence of the additive impact of different risk factors (85) and in the frequency with which they occur together in the same population and in the same individuals. In a particular population, epidemiological data on its specific “community syndrome” (56) of concomitantly occurring diseases and associated characteristics provide the foundation for such intervention. The value of this multiple risk factor approach has already been demonstrated in practice (83, 84). The limited evidence presented above supports the worthwhileness of such intervention among the elderly. This may both enhance the quality of life, by reducing the risk of morbidity and disability, and extend life expectancy. Intervention may be expected to have a greater absolute short-term effect on the burden of cardiovascular diseases than similar intervention among younger people, in spite of its smaller impact on the individual’s risk. The specific measures which are probably of value among the elderly include blood pressure and weight control, the stopping of cigarette smoking, and (with less certainty) the control of blood lipids and the encouragement of physical activity. This intervention has two main aspects: changes in behavior and the use of pharmacological agents. While an important contribution may be made by action directed at the public as a whole, such as community health education and changes in the composition of commercially available foodstuffs, the successful control of multiple risk factors requires personalized care. This personal care includes individual counseling and long-term treatment aimed at the control of risk factors, as well as surveillance procedures to determine the presence of and changes in risk factors. Different organizational set-ups are feasible for the provision of this preventive care. The natural home for these activities seems, however, to be within the ordinary primary health care system, as part of the activities of practitioners who are in a continuing first-line relationship with the public. Not only is this a suitable setting for the organization of screening and surveillance activities and for the provision of long-term treatment (43), but it provides opportunitites for action at the family and local community levels as well as at the individual level. An illustrative program, set up as a trial and demonstration of the building of this preventive approach into primary health care, is the CHAD program conducted by the Department of Social Medicine of the Hebrew UniversityHadassah Medical School in a neighborhood of Jerusalem (“CHAD” = “Community syndrome of Hypertension, Atherosclerosis and Diabetes”). This program, which is described in more detail elsewhere (56, 57), is provided as an integral part of a family practice, and increasingly as a central feature of this

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practice. The program is a community-oriented one founded on epidemiological surveillance of the practice population as a whole and directed at the control of multiple cardiovascular risk factors in this population. The management of the elderly does not differ from that of other adults, and has presented no special difficulties. An evaluation of the program’s effectiveness is at present under way, using an adjacent neighborhood as a control population. The program includes action at individual, family, and community levels. Individual care is based on standardized examination methods, uniform treatment guidelines, and defined surveillance regimes for persons at specified levels of risk (as determined by blood pressure etc.). This care is provided at special CHAD sessions conducted by family physicians and nurses, as well as during other activities of the practice. A specific program is prepared for each individual, including surveillance and the management of all the risk factors to which he is exposed; people requiring no specific care are advised about health maintenance. Care is aimed mainly at bringing and keeping blood pressure below 160195mm Hg, serum cholesterol below 200 mg %, and relative weight below 110% of the standard adopted (48), and at modifying diet, stopping cigarette smoking and increasing physical activity. The methods used include individual and family counseling and community health education and (where necessary) medicinal treatment for hypertension, hyperlipidemia, and diabetes. In populations where the cardiovascular diseases under consideration are common, a large proportion of adults are exposed to at least one risk factor (56,86), so that a comprehensive intervention program of this sort means a considerable work load. Where resources of time and manpower are inadequate, a multifactorial program may be feasible only if intervention is limited to people at especially high risk. This may be done in three main ways. First, by using more stringent criteria-e.g., higher cutting points for blood pressure and cholesterol-when deciding that a specific risk factor merits control. Secondly, by concentrating attention on people exposed to at least two modifiable risk factors (8). And thirdly, by taking account of other characteristics, not necessarily modifiable, which indicate increased vulnerability. This last approach finds expression in such recommendations as that moderate hypertension should be treated only if clinically manifest target organ damage or certain other characteristics are present. Attempts to develop generally applicable scoring systems for the calculation of the individual’s risk have not so far proved completely successful (60, 85). There is no doubt that the effective control of cardiovascular risk factors demands changes in the attitudes and emphasis of physicians and other health workers. It has been suggested that the “prevention of cardiovascular disease may actually require the evolution of a new breed of physicians and associated medical personnel concerned with adult preventive medicine” who “must come to regard the occurrence of strokes, coronary heart disease, congestive failure and peripheral vascular disease in persons under periodical medical surveillance as medical failures rather than the starting point of medical management” (35). The challenge facing practitioners today is whether they can evolve into this new breed.

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