The case for prescribing statins to people with atherosclerotic cardiovascular disease is strong, and it is realistic to attribute the improved survival largely to the effects of these drugs.1 2 The case for statins in men and women without existing cardiovascular disease is less clear and was highlighted in a recent Cochrane systematic review.3

The review, slightly more restrictive in its inclusion criteria than other recent analyses which typically considered twice as many people, looked at 14 trials of about 34 000 people with no evidence of cardiovascular disease. The review found that in people taking statins, all cause mortality—on average 1% per year of observation—was reduced by 17%, fatal and non-fatal coronary heart disease by 28%, fatal and non-fatal stroke by 22%, and the rate of revascularisation by 34% over a period of three to four years. Comparable numbers have been reported in other recent meta-analyses,4 5 6 7 so it is safe to assume that the beneficial effects of statins are substantial for coronary heart disease and coronary revascularisation, more modest for stroke, and probably between 10% and 15% for overall …