Lipid lowering drugs reduce the relative risk of coronary heart disease events
and coronary heart disease mortality by about 30 per cent, a meta-analysis has
shown. However, their effect on all-cause mortality over five years is small
and not significant.
Dr Michael Pignone (assistant professor of medicine, University of North Carolina,
US) and colleagues conducted a meta-analysis to assess the use of lipid lowering
agents for primary prevention of coronary heart disease. They included randomised
trials published between January, 1994, and June, 1999, which lasted over one
year and measured clinical end points, including coronary heart disease events,
coronary heart disease mortality and all-cause mortality. The authors found
that treatment reduced the relative risk of coronary heart disease events by
30 per cent compared with placebo. The relative risk of coronary heart disease
mortality was reduced by 29 per cent. The effect on all-cause mortality was
either small or not present (odds ratio 0.94, range 0.81 to 1.09).
The authors comment that failure of drug treatment to reduce all-cause mortality
in primary prevention is most likely to be because of a generally low risk of
mortality in the patient populations studied. Treatment targeted at primary
prevention patients with higher levels of coronary heart disease events might
reduce all-cause mortality, they say. Low-risk populations might also achieve
significant reduction in all-cause mortality if they were treated for longer
than the short follow-up periods used in the trials. Concomitant use of other
drugs might also lower absolute risk for large numbers of patients at moderate
risk of coronary heart disease, they add (British Medical Journal 2000;321:983).