Clinical trials of cholesterol lowering therapies have demonstrated consistent near-term benefits for patients with established coronary heart disease (CHD) and long-term benefits for those with severe hypercholesterolemia who are currently free of clinical CHD (see "Clinical trials of cholesterol lowering in patients with cardiovascular disease or diabetes"). Unfortunately, these trials have typically excluded older patients.
The bias against older individuals stems from illusory concerns regarding life expectancy, comorbidity, safety of lipid lowering agents, and cost-benefit analysis of preventive care in older adults. In fact, the absolute risk for CHD increases dramatically with age in both men and women (figure 1). Thus, the absolute number of persons benefiting from cholesterol lowering should be greater in older adults [1,2].
CARDIOVASCULAR DISEASE IN OLDER ADULTS
A large proportion of older individuals will suffer from CHD. In men over the age of 65, for example, nearly one-half of all deaths are attributed to CHD, compared to less than 25 percent for all cancers and less than 2 percent for all infections. An even higher proportion of deaths are due to CHD in older women (56 percent) with less than 20 percent being due to cancer.
Age-related changes in lipoprotein metabolism — Longitudinal studies have shown that total cholesterol levels increase in males after the onset of puberty until age 50. This is followed by a plateau until age 70, with the serum cholesterol concentration then falling slightly. Although it has been suspected that the latter change may be an artifact resulting from CHD deaths in hypercholesterolemic men , the most important factor influencing cholesterol may be weight change . The reduction in total and LDL cholesterol and the increase in HDL-cholesterol in older men, primarily occur in those who lost weight, while age is not a factor.
In women, the serum cholesterol concentration is slightly higher than in men prior to age 20 to 25. Between the ages of 25 to 55, the serum cholesterol rises although at a slower incremental rate than in men. Cholesterol levels in women are equal to those of men between the ages of 55 to 60 and exceed those in men in older age groups.