A study suggests that more than one million adults taking statins may not need the cholesterol-lowering drugs, raising questions about how widely they are prescribed for people at relatively low risk of heart disease. However, experts have urged patients not to stop taking statins without medical advice, as the medicines can substantially reduce the risk of heart attacks and strokes for those who need them.

The finding appears to concern whether some people meet current thresholds for preventive treatment rather than whether statins are ineffective. Any decision to start or stop treatment should take account of an individual’s cardiovascular risk, medical history and possible side effects, with changes discussed with a clinician.