Predictors of falling cholesterol levels in older adults:
The Cardiovascular Health Study.
Declining cholesterol levels are common in older persons and are often considered a harbinger of serious illness or death, but factors related to short-term decline in cholesterol remain poorly described. Prospective data from 1,684 women and 1,155 men aged > 66, not taking lipid-lowering medications and with serum cholesterol measured in 1992-93 and 1996-97 were examined for distribution and correlates of four-year change in cholesterol level. Mean serum cholesterol changed an average of -6.3 mg/dl between examinations after correction for measurement error due to laboratory and within person variability. Declines were greater in white (-7.3 mg/dl) than black (-1.4 mg/dl) participants and in those in good/ excellent health (-6.9 mg/dl) vs. fair/poor health (-3.2 mg/dl; both p < 0.01). Subjects in the highest quartile of decline (-22 through -150 mg/dl) had higher prevalences of cancer, coronary disease, and claudication at entry than those in the other three quartiles. Factors associated with decline > 16 mg/dl on multivariate analysis included age, male gender, white race, weight loss between exams, and higher levels of albumin, cholesterol, and white blood cell count in 1992-93 (all p < 0.03). Cholesterol declined 6.8 mg/dl more in men than in women and 3.0 mg/dl more in whites than blacks in multivariate analyses adjusting for age, weight change, gender, low cholesterol diet, internal carotid thickness, and levels of albumin, fibrinogen, cholesterol, and white blood cell count. In this same analysis, a 5.1 kg decrement in weight was associated with a 5.1 mg/dl decline in cholesterol level (p < 0.001). Higher carotid thickness and fibrinogen levels were associated with rises in cholesterol between exams, all other factors held constant. Substantial four-year declines in cholesterol levels occur in older adults and appear primarily related to unmodifiable factors such as advancedage and male gender. The relationship between weight loss, which is often unintentional in the elderly, and declining serum cholesterol should be further explored to clarify the mechanisms of the sometimes marked age-related declines in cholesterol levels observed at advanced ages.