Cholesterol and other lipids predict coronary heart disease and ischaemic stroke in the elderly, but only in those below 70 years

The prediction of coronary heart disease (CHD) and stroke by total and low density lipoprotein (LDL) cholesterol in older persons remains problematical. This study tests the hypothesis that cholesterol and other risk factors may be differentially predictive of CHD and ischaemic stroke in older persons when they are segregated into different age groups. CHD and ischaemic stroke outcomes were recorded during 129 months follow-up in a cohort of 2805 men and women of 60 years and older. There were 899 CHD events (32/100) and 326 stroke events (12/100). Using Cox proportional hazards, outcomes were modelled for the total cohort and for age groups 60–69, 70–79, and 80+ years. Total cholesterol, LDL cholesterol, serum apo-B, total cholesterol/high density lipoprotein (HDL) cholesterol and apo-B/apo-A1 were significant predictors of CHD in the total cohort, but significant only in the sub-group of 60–69 years. The respective hazard ratios (CI 95%) were 1.21 (1.09–1.35), 1.21 (1.09–1.35), 1.25 (1.13–1.39), 1.25 (1.14–1.37) and 1.21 (1.10–1.38). Similar findings were applicable with respect to ischaemic stroke in the age group of 60–69 years. Total cholesterol predicted CHD in men above a threshold value of 7.06 mmol/l and in women above 7.8 mmol/l, but with stroke the prediction was incremental. Other risk factors such as HDL cholesterol, triglycerides, lipoprotein(a), diabetes, hypertension and smoking predicted CHD, although only HDL and hypertension similarly predicted ischaemic stroke. The findings support a case for cholesterol testing in older subjects up to 70 years, in whom there is ancillary evidence of CHD and stroke prevention through treatment designed to reduce LDL cholesterol.