MRFIT and the Oslo study.

THE LARGE American three-factor 1 and the much smaller Norwegian two-factor 2 coronary heart disease (CHD) prevention trials have come out with different results, the former ending inconclusively, the latter with a significantly reduced incidence of total cardiovascular and CHD end points, and substantial, although nonsignificant, reductions in CHD and total mortality. The Oslo diet-smoking trial in 1,232 high-risk, normotensive, healthy men aged 40 to 49 years, representing the 20% upper risk of a screened male population of 16,200, combined lipid-lowering dietetic intervention with smoking cessation advice. The trial lasted from five to 6 1/2 years. Differences Between the Trials There are two main differences in study design between the two trials. The Multiple Risk Factor Intervention Trial (MRFIT) combined hygienic-dietetic intervention measures against smoking and eating habits with drug treatment of the hypertensive subjects (almost two thirds of the intervention group), while the Oslo Study management decided to exclude