RELATIONSHIP OF C-REACTIVE PROTEIN TO RISK OF CARDIOVASCULAR-DISEASE IN THE ELDERLY - RESULTS FROM THE CARDIOVASCULAR HEALTH STUDY AND THE RURAL HEALTH PROMOTION PROJECT

Markers of inflammation, such as C-reactive protein (CRP), are related to risk of cardiovascular disease (CVD) events in those with angina, but little is known about individuals without prevalent clinical CVD. We performed a prospective, nested case-control study in the Cardiovas cular Health Study (CHS; 5201 healthy elderly men and women). Case sub jects (n=146 men and women with incident CVD events including angina, myocardial infarction, and death) and control subjects (n=146) were ma tched on the basis of sex and the presence or absence of significant s ubclinical CVD at baseline (average follow-up, 2.4 years). In women bu t not men, the mean CRP lever was higher for case subjects than for co ntrol subjects (P less than or equal to.05). In general, CRP was highe r in those with subclinical disease. Most of the association of CRP wi th female case subjects versus control subjects was in the subgroup wi th subclinical disease: 3.33 versus 1.90 mg/L, P<.05, adjusted for age and time of follow-up. Case-control differences were greatest when th e time between baseline and the CVD event was shortest. The strongest associations were with myocardial infarction, and there was an overall odds ratio for incident myocardial infarction for men and women with subclinical disease (upper quartile versus lower three quartiles) of 2 .67 (confidence interval [CI]=1.04 to 6.81), with the relationship bei ng stronger in women (4.50 [CI=0.97 to 20.8]) than in men (1.75 [CI=0. 51 to 5.98]). We performed a similar study in the Rural Health Promoti on Project, in which mean values of CRP were higher for female case su bjects than for female control subjects, but no differences were appar ent for men. Comparing the upper quintile with the lower four, the odd s ratio for CVD case subjects was 2.7 (CI=1.10 to 6.60). In conclusion , CRP was associated with incident events in the elderly, especially i n those with subclinical disease at baseline.