Risk factors for coronary heart disease in the prospective Dubbo Study of Australian elderly

A new prospective study of non-institutionalised Australian elderly 60 years and over commenced in Dubbo in 1988, comprising 1236 men and 1569 women. This report examines clinical and socio-demographic predictors of coronary heart disease (CHD) over a median 62 months follow-up. CHD incidence rates (ICD-9-CM codes 410-414) were higher in men than women until 79 years, thereafter, the rates for recurrent disease were higher in women. Incidence rates for recurrent disease were three-fold those for initial disease. In Cox proportional hazards analysis, the significant predictors of all CHD were: advancing age, prior CHD (relative risk (RR) = 2.50 and 2.15 in men and women, respectively), use of anti-hypertensive medication (RR = 1.92 and 1.75 in men and women, respectively), diabetes (RR = 1.67 and 1.53 in men and women, respectively), serum cholesterol, low density lipoprotein cholesterol and serum apo B in men (RR = 1.24), serum triglycerides in women (RR = 1.23), high density lipoprotein cholesterol in men (RR = 0.82), lipoprotein(a) in women (RR = 1.99), and poorer self-rating of health (RR = 1.48 and 1.93 in men and women, respectively). Serum cholesterol was not predictive of CHD in men beyond 74 years. Isolated systolic hypertension predicted CHD in women (RR = 3.76), but not in men (RR = 1.20). The findings highlight key risk factors for CHD in the elderly.