Jacob J. Feldman

Pulse rate, coronary heart disease, and death : the NHANES I epidemiologic follow-up study

To determine whether associations of elevated resting pulse rate with CHD incidence or death in white men are independent of other risk factors and whether such associations exist for women and blacks, data were examined from the NHANES I Epidemiologic Follow-up Study. Over a follow-up period of 6 to 13 years, elevated RR for CHD incidence were found for older white men with baseline pulse greater than 84 beats/min compared with less than 74 beats/min after controlling multiple risk factors (RR = 1.37, 95% CL 1.02, 1.84). Risks of death from all causes, cardiovascular diseases, and noncardiovascular diseases were also elevated for white men with elevated pulse rate independent of other risk factors. CHD incidence was increased in white women with elevated pulse rate. Risks of death from all causes, cardiovascular diseases, and noncardiovascular diseases, were also elevated for white men with elevated pulse rate independent of other risk factors. CHD incidence was increased in white women with elevated pulse rate. Risk of death from all causes and cardiovascular diseases was elevated in black men and women with elevated pulse rate. Risk of death from noncardiovascular disease was elevated in black men with elevated pulse rate. The association with cardiovascular death was particularly striking in black women, even after adjusting for baseline risk factors (RR 3.03, 95% CL 1.46, 6.28). Further studies are needed to assess associations of pulse rate with CHD in blacks and to elucidate mechanisms in all groups.

An overview of body weight of older persons, including the impact on mortality The national health and nutrition examination survey i-epidemiologic follow-up study

The authors studied distributions of body weight for height, change in body weight with age, and the relationship between body mass index and mortality among participants in the Epidemiologic Follow-up Study of the first National Health and Nutrition Examination Survey (NHEFS) (n = 14,407), a cohort study based on an representative sample of the U.S. population. Percentiles of body weight for height according to age and sex are presented. Cross-sectional analyses of body weight suggest that mean body weight increases with age until late middle age, then plateaus and decreases for older aged persons. However, longitudinal analysis of change in weight with age shows that younger persons in the lower quintile at baseline tend to gain more than those in the higher quintile. Older persons in the higher quintile at baseline have the greatest average loss in weight. The relationship of body mass index to mortality is a U-shaped curve, with increased risks in the lowest and highest 15% of the distribution. Increased risk of mortality associated with the highest 15th percentile of the body mass index distribution, as well as the highest 15% of the joint distribution of body mass index and skinfold thickness, is statistically significant for white women. However, the risk diminishes when adjusted for the presence of disease and factors related to disease. More noteworthy is the fact that there is a statistically significant excess risk of mortality for both race and sex groups in the lowest 15% of the body mass index distribution after adjusting for smoking history, and presence of disease. Those in the lowest 15% of the joint body mass index and skinfold thickness distribution, were also at increased risk. Risk of mortality for both men and women who have lost 10% or more of their maximum lifetime weight within the last 10 years is statistically significant, even when controlling for current weight. This study has replicated previously reported relationships, while correcting for several methodological issues.

Cohort study of effect of being overweight and change in weight on risk of coronary heart disease in old age.

Abstract Objective: To evaluate risk of late life coronary heart disease associated with being overweight in late middle or old age and to assess whether weight change modifies this risk. Design: Longitudinal study of subjects in the epidemiological follow up study of the national health and nutrition examination survey I. Setting: United States. Subjects: 621 men and 960 women free of coronary heart disease in 1982-84 (mean age 77 years). Main outcome measure: Incidence of coronary heart disease. Results: Body mass index of 27 or more in late middle age was associated with increased risk of coronary heart disease in late life (relative risk=1.7 (95% confidence interval 1.3 to 2.1)) while body mass index of 27 or more in old age was not (1.1 (0.8 to 1.5)). This difference in risk was due largely to weight loss between middle and old age. Exclusion of those with weight loss of 10% or more increased risk associated with heavier weight in old age (1.4 (1.0 to 1.9)). Thinner older people who lost weight and heavier people who had gained weight showed increased risk of coronary heart disease compared with thinner people with stable weight. Conclusions: Heavier weight in late middle age was a risk factor for coronary heart disease in late life. Heavier weight in old age was associated with an increased risk once those with substantial weight loss were excluded. The contribution of weight to risk of coronary heart disease in older people may be underestimated if weight history is neglected. Key messages Little is known about the effects of being overweight (defined as a body mass index of ≥27) in old age on risk of heart disease In this study older people who were overweight had an increased risk of coronary heart disease once weight history was accounted for Weight history, particularly in late middle age, is important in assessing risk of coronary disease in older people Older heavier people who gained more than 10% of midlife body weight or thinner older people who had lost 10% or more of body weight show high risk compared with thinner people with stable weight

The low cholesterol-mortality association in a national cohort

The relationship of low serum cholesterol and mortality was examined in data from the NHANES I Epidemiologic Followup Study (NHEFS) for 10,295 persons aged 35-74, 5833 women with 1281 deaths and 4462 men with 1748 deaths (mean (followup = 14.1 years). Serum cholesterol below 4.1 mmol/l was associated with increased risk of death in comparison with serum cholesterol of 4.1-5.1 mmol/l (relative risk (RR) for women = 1.7, 95% confidence interval (CI) = (1.2, 2.3); for men RR = 1.4, CI = (1.1, 1.7)). However, the low serum cholesterol-mortality relationship was modified by time, age, and among older persons, activity level. The low serum cholesterol-mortality association was strongest in the first 10 years of followup. Moreover, this relationship occurred primarily among older persons (RR for low serum cholesterol for women 35-59 = 1.0 (0.6, 1.8), for women 70-74, RR = 2.1 (1.2, 3.7); RR for low serum cholesterol for men 35-59 = 1.2 (0.8, 2.0), for men 70-74, RR = 1.9 (1.3, 2.7)). Among older persons, however, the low serum cholesterol-mortality association was confined only to those with low activity at baseline. Factors related to underlying health status, rather than a mortality-enhancing effect of low cholesterol, likely accounts for the excess risk of death among persons with low cholesterol. The observed low cholesterol-mortality association therefore should not discourage public health programs directed at lowering serum cholesterol.

Implications of health status in analysis of risk in older persons.

This article explores the hypothesis that health status in old age acts as a summary measure of health exposures over time and, as such, plays a central role as a determinant of survival and morbidity trajectories in old age. Evidence is presented for the utility of health status as a modifier of risk in other areas of gerontologic research, and an example of modification pertinent to the cholesterol-heart disease controversy in old age is presented. The potential of differential health status in old age to affect both risk factors and risk estimates in epidemiologic analyses may be an important principle as epidemiologists continue to develop research to preserve and augment the quality of life in old age.

Is weight loss a modifier of the cholesterol-heart disease relationship in older persons? Data from the NHANES I epidemiologic follow-up study

The relationship between cholesterol and 14-year incidence of coronary heart disease was compared for men and women of two age groups, 25 to 64 years and 65 to 74 years. While cholesterol levels of 6.2 mmol/L or higher were associated with a risk of coronary heart disease in the younger group, this was not true for either men or women aged 65 to 74. Further analyses for older persons showed that weight loss modified the cholesterol-heart disease relationship. Those with stable weight showed a positive relationship between cholesterol and coronary heart disease, similar to the younger age group (relative risk [RR] = 1.8 [95% confidence interval: 1.1, 2.9] for men; RR = 1.6 [.7, 3.4] for women). Among those with a weight loss of 10% or more, the relationship of cholesterol to heart disease was inverse (RR = .8 [.5, 1.2] for men; RR = .6 [.3, 1.0] for women). These data suggest that the relationship of cholesterol to coronary disease in healthier older persons may be similar to that in younger persons, and that health status should be considered in analyses of cholesterol risk in old age.