Cholesterol as a Risk Factor for Coronary Heart Disease in Elderly Men The Baltimore Longitudinal Study of Aging John D. Sorkin, MD, Reubin Andres, MD, Denis C. Muller, MS, Howard L. Baldwin, BS, and Jerome L. Fleg, MD In order to explore the relationship of cholesrerol to coronary heart disease (CHD), defined as angina pectoris, myocardial infarction, and sudden coronary death, in older men, a group of IO52 men, participants in the Baltimore Longitudinal Study on Aging, were examined. Subjects were stratifed into three age groups, 28 to 64, 65 to 74, and 75 to 97 years old. In all three age groups, cholesterol was a significant risk factor for CHD. In the oldest age group (n = 250), the relationship between cholesterol and risk was linear (P = .003) us opposed to younger age groups where the relationship was exponential. This study extends the age range in which hypercholesterolemia has been shown to be associated with CHD to include the 75- to 97-year range. Ann Epidemiol 1992;2:59-67. KEY WORDS:
Hyperchoksterolemia,
elderly men, coronary heart disease.
INTRODUCTION
A recent series of papers and conferences resulted in recommendations published by the National Cholesterol Education Program (NCEP) (l), which codified a stepwise approach to diagnosing and managing hypercholesterolemia. One recurring criticism of those recommendations is that they are based largely on studies of middle-aged men. The role of cholesterol as a risk factor for coronary heart disease (CHD) in the elderly remains controversial. To explore this controversy, we analyzed the relationship of total serum cholesterol level to the development of CHD, defined as angina pectoris, myocardial infarction, and sudden cardiac death, in 1052 men aged 29 to 97 years old who were enrolled in the Baltimore Longitudinal Study of Aging (BLSA).
METHODS
The BLSA conducted at the Gerontology Research Center (GRC) is a 32-year-old, ongoing, open-panel study of normal aging processes. The BLSA, begun in 1958, is a study of healthy, ambulatory, community-dwelling, highly educated, middle class adults aged 17 to 102 years (2). New subjects are recruited to maintain a stable population profile. Until 1978 only men were studied. This article deals only with men; our 12-year experience with women has not yet provided enough CHD events for analysis.
From the Laboratories of Clinical Physiology (J.F.), Gerontology Research Center, National Address reprint requests to: John D. Sorkin, Aging, 4940 Eastern Avenue, Baltimore, MD Received November 28, 1990; revised May
(J.S., R.A., D.M., H.B.) and of Cardiovascular Science Institute on Aging, Baltimore, MD. MD, Gerontology Research Center, National Institute on 21224. 17, 1991.
Published 1992by Elsevier Science Publishing Co., Inc.
1047~2797492/$00.00
60
Sorkin et al. CHOLESTEROL
AEP Vol. 2, No. II2
TABLE
Age
JanuaryiMarch 1992: 59-67
AND CHD IN ELDERLY MEN
Characteristics of subjects
1
Analysis
group
Number of subjects4
Number of events
Mean age (Y)
(A) 29-64 y 1. LRC quintdes
,“: Q3 (24 (25
144 162 138 188 169
11 16 20 43 65
38
225 348 228 801
19 55 81 155
39 44 48 44
61 74 68 78 76
9 19 12 23 29
68 68 68 67 68
94 156 107 357
17 42 33 92
68 68 68 68
65 59 38 60 28
13 I3 11 20 10
78 78 77 78 78
92 114 44 250
19 29 19 67
78 78 78 78
43 43 44 49
2. NCEP groups Gl G2 G3 3. Total (B) 65-74
y 1. LRC quintiles
:: :: Q5 2. NCEP groups Gl G2 G3 3. Total (C) 75-97
y 1. LRC quintiles :t (23 ,“; 2. NCEP groups Cl G2 G3 3. Total
ySome subpcts appear m TWOor even three age groups since they enter the study at one age but may then “graduate” to the next older age group during the course of the longitudinal study (see Statist& Methods).
Systematic cholesterol and triglyceride analyses began in 1963. High-density-lipoprotein (HDL) and low-density-lipoprotein (LDL) assays were begun in 1985. There have not been enough CHD events since 1985 to warrant including these subfractions in this report. After an overnight fast, blood for lipid assay was drawn between 7 and 8 AM while the subject was supine. Several different assay methods were used to measure cholesterol over this 27-year period. A summary of the methods from 1963 through June 1977 appears in the article by Hershcopf and colleagues (3). From July 1977 through August 1983, cholesterol was measured at Bioscience Laboratories (Van Nuys, CA) using the method of Wybenga and associates (4). One-eighth of the samples were split and run in tandem, as a control, at the GRC, using a modification of the method of Abel1 and coworkers (5). From September 1983 forward, the lipid assay has been performed exclusively at the GRC.
Sorkin et al. CHOLESTEROL AND CHD IN ELDERLY MEN
AEP Vol. 2, No. 112 ]anuarylMarch 1992: 59-67
TABLE
1
Mean follow-up (Y)
Mean number of assays
Mean cholesterol mg/dL (mM)
Cholesterol Range mg/dL
mM
17 16
172 200 217 237 273
(4.45) (5.17) (5.61) (6.13) (7.06)
Hyperchoksterolemia,
elderly men, coronary heart disease.
INTRODUCTION
A recent series of papers and conferences resulted in recommendations published by the National Cholesterol Education Program (NCEP) (l), which codified a stepwise approach to diagnosing and managing hypercholesterolemia. One recurring criticism of those recommendations is that they are based largely on studies of middle-aged men. The role of cholesterol as a risk factor for coronary heart disease (CHD) in the elderly remains controversial. To explore this controversy, we analyzed the relationship of total serum cholesterol level to the development of CHD, defined as angina pectoris, myocardial infarction, and sudden cardiac death, in 1052 men aged 29 to 97 years old who were enrolled in the Baltimore Longitudinal Study of Aging (BLSA).
METHODS
The BLSA conducted at the Gerontology Research Center (GRC) is a 32-year-old, ongoing, open-panel study of normal aging processes. The BLSA, begun in 1958, is a study of healthy, ambulatory, community-dwelling, highly educated, middle class adults aged 17 to 102 years (2). New subjects are recruited to maintain a stable population profile. Until 1978 only men were studied. This article deals only with men; our 12-year experience with women has not yet provided enough CHD events for analysis.
From the Laboratories of Clinical Physiology (J.F.), Gerontology Research Center, National Address reprint requests to: John D. Sorkin, Aging, 4940 Eastern Avenue, Baltimore, MD Received November 28, 1990; revised May
(J.S., R.A., D.M., H.B.) and of Cardiovascular Science Institute on Aging, Baltimore, MD. MD, Gerontology Research Center, National Institute on 21224. 17, 1991.
Published 1992by Elsevier Science Publishing Co., Inc.
1047~2797492/$00.00
60
Sorkin et al. CHOLESTEROL
AEP Vol. 2, No. II2
TABLE
Age
JanuaryiMarch 1992: 59-67
AND CHD IN ELDERLY MEN
Characteristics of subjects
1
Analysis
group
Number of subjects4
Number of events
Mean age (Y)
(A) 29-64 y 1. LRC quintdes
,“: Q3 (24 (25
144 162 138 188 169
11 16 20 43 65
38
225 348 228 801
19 55 81 155
39 44 48 44
61 74 68 78 76
9 19 12 23 29
68 68 68 67 68
94 156 107 357
17 42 33 92
68 68 68 68
65 59 38 60 28
13 I3 11 20 10
78 78 77 78 78
92 114 44 250
19 29 19 67
78 78 78 78
43 43 44 49
2. NCEP groups Gl G2 G3 3. Total (B) 65-74
y 1. LRC quintiles
:: :: Q5 2. NCEP groups Gl G2 G3 3. Total (C) 75-97
y 1. LRC quintiles :t (23 ,“; 2. NCEP groups Cl G2 G3 3. Total
ySome subpcts appear m TWOor even three age groups since they enter the study at one age but may then “graduate” to the next older age group during the course of the longitudinal study (see Statist& Methods).
Systematic cholesterol and triglyceride analyses began in 1963. High-density-lipoprotein (HDL) and low-density-lipoprotein (LDL) assays were begun in 1985. There have not been enough CHD events since 1985 to warrant including these subfractions in this report. After an overnight fast, blood for lipid assay was drawn between 7 and 8 AM while the subject was supine. Several different assay methods were used to measure cholesterol over this 27-year period. A summary of the methods from 1963 through June 1977 appears in the article by Hershcopf and colleagues (3). From July 1977 through August 1983, cholesterol was measured at Bioscience Laboratories (Van Nuys, CA) using the method of Wybenga and associates (4). One-eighth of the samples were split and run in tandem, as a control, at the GRC, using a modification of the method of Abel1 and coworkers (5). From September 1983 forward, the lipid assay has been performed exclusively at the GRC.
Sorkin et al. CHOLESTEROL AND CHD IN ELDERLY MEN
AEP Vol. 2, No. 112 ]anuarylMarch 1992: 59-67
TABLE
1
Mean follow-up (Y)
Mean number of assays
Mean cholesterol mg/dL (mM)
Cholesterol Range mg/dL
mM
17 16
172 200 217 237 273
(4.45) (5.17) (5.61) (6.13) (7.06)
