Hypercholesterolaemia and its treatment in Singapore with implications for screening

The National University of Singapore Heart Study is a cross-sectional survey of the whole of Singapore from 1993 to 1995 with a random sample of 961 persons aged 30 to 69 years (response rate 71.2%). Serum lipids were measured enzymatically on an autoanalyser (Ektachem, kodak). Hypercholesterolaemia was diagnosed if the person was on lipid lowering drugs or had a serum cholesterol > or = 6.5 mmol/L (250 mg/dL). Results for the 40 to 64 age group are presented. The proportion and number in Singapore with hypercholesterolaemia were high, 23.7% and 186,544 persons respectively. However, they declined with the additional requirement of coronary heart disease (CHD) or risk factors (i.e. cigarette smoking, hypertension or diabetes mellitus), and were small if only hypercholesterolaemic persons with CHD were included, 1.6% and 13,126 persons respectively. For both genders, the proportions on drugs increased with the added options of CHD or risk factors, so that for persons with hypercholesterolaemia and CHD the proportion on drugs was very high i.e. 84.0%. However, 11.2% of persons with only hypercholesterolaemia (i.e. without CHD or other risk factors) had been prescribed drugs. The main conclusions were:1) The use of different criteria for the screening and treatment of hypercholesterolaemia would involve large differences in the number of Singaporeans on lipid lowering drugs and this should be considered when deciding policy and 2) Medical practitioners currently to some extent do consider the presence of CHD or other risk factors when prescribing lipid lowering drugs for hypercholesterolaemia.