IMPROVED TARGETING OF PRIMARY PREVENTION AFTER WOSCOPS

Background and Aim: To review primary preventive cholesterol-lowering trials with the aim of finding improved targeting of primary preventio n after the West of Scotland Coronary Preventive Study (WOSCOPS). Meth ods and Results: Twelve randomized primary preventive cholesterol-lowe ring trials were meta-analysed with respect to coronary heart disease (CHD) incidence and total mortality. The relations between degree of c holesterol reduction and CHD incidence were analysed. Comparisons of r esults with the WOSCOPS trial findings were made. The intention was to treat populations when available. The meta-analysis consists of 2697 cases of CHD, 3634 deaths from all caused out of 127880 subjects parti cipating in these trials. Trial duration median was 5 years and the ra nge was 1 to 10 years. Cholesterol reductions were obtained by dietary changes and drugs alone or in combination with other intervention mod alities such as antihypertensive treatment and/or antismoking advice. The control groups were either open or placebo blinded. The meta-analy sis showed that CHD incidence was clearly reduced by cholesterol reduc tion, all trials combined. A major heterogeneity in trial outcome appe ared to be due to differences in the degree of cholesterol reduction. A dose-response relationship linear on the log odds ratio scale was pr esent at least up to 20% cholesterol reduction. A neutral effect was i ndicated if no cholesterol reduction was achieved or if baseline chole sterol was approximately 5.2 mmol/l. Benefits were found at rather low levels of absolute risk and were consistent with the findings from th e WOSCOPS trial alone that showed major risk reduction profiles for pe ople without risk factors (other than elevated baseline cholesterol) p resent at baseline. The effects were neutral on all-cause mortality, a ll trials combined. Cholesterol dose-response relationships were more difficult to interpret due to the confounding of clofibrate on non-car diovascular causes of death. Conclusions: If the safety of statins can be assumed in long-term treatment, the meta-analysis and the WOSCOPS findings strongly indicate that healthy men with cholesterol above 5.2 mmol/l could greatly benefit from statin treatment. (C) 1997, Medikal Press.