Costs of aspirin and statins in general practice

Aspirin and statins are the two drugs most commonly indicated for secondary prevention of atherosclerotic disease in the UK. Statin treatment, which is more expensive, is under-prescribed.

To assess the expenditure in Greater Manchester general practices on aspirin and statins.

Survey of general practice records.

Practice registers were searched for patients receiving regular prescriptions for aspirin. For each patient, the next patient of the same sex, aged within +/- 5 years, not on aspirin, acted as a control. Details of all medications were recorded. In a sub-study, records of 100 patients on aspirin were studied to determine indications for aspirin prescription.

There were 1003 (511 men, 492 women) in each group; mean age was 70 years in both groups. In the sub-study, 79% of patients received aspirin for established vascular disease, 9% for hypertension, 5% for diabetes mellitus, 5% for unknown reasons and 2% for arthritis. Of the patients on aspirin, 67% received dispersible aspirin 75 mg/day. The rest were on higher doses (10%) or on more expensive preparations (22%), costing up to 22.4 p/day. The mean daily cost of aspirin was 1.7p. Dyspepsia treatment was received by 266 patients and 194 controls (p<0.001). There was a wide range of dyspepsia medications (10-306p/day), averaging in the groups as a whole 15.5p/day in patients and 12.5p/day in controls. Of the patients on aspirin, 28% received statins, compared to 4% of controls. Mean daily expenditure on statins in patients was 23.4p.

Assuming the difference in the use of medication for dyspepsia between patients and controls was due to aspirin, the full cost of aspirin treatment was 4.7p/day. Statins were probably under-prescribed in aspirin-takers, many of whom would have been at high CHD risk.