peer reviewed ; BACKGROUND: In Belgium, regulations restrict the reimbursement of statins to patients with total serum cholesterol above 250 mg/dl (6.41 mmol/l) after a three-month lipid-lowering diet. We investigated the possible impact of these regulations on characteristics of Belgian patients receiving a lipid-lowering drug. DESIGN: From 1998 to 2000, standard questionnaires on coronary risk factors and treatments with lipid-lowering drugs were completed by 301 GPs sampled at random in the 11 Belgian Provinces. Questionnaires had to be completed for 18 consecutive patients 35 years old or more attending GPs' practices, irrespective of the underlying motive for attendance. RESULTS: Of the 5511 patients included in the study, 1519 (28%) had established coronary disease or diabetes mellitus, or > or = 2 non-cholesterol coronary risk factors. Most (70%) of these patients were not treated with a lipid-lowering drug. Only 22% of patients with established coronary disease, 10% of patients with diabetes mellitus and 9% of patients with > or = 2 coronary risk factors were treated with a statin. Fifty-nine percent of fibrate users and 50% of statin users had a pre-treatment cholesterol level above 250 mg/dl, but had no or only one non-cholesterol coronary risk factor. CONCLUSIONS: In Belgium, the majority of patients at higher risk of coronary event do not benefit from lipid-lowering drugs, particularly the statins. In contrast, one of two statin users and three of five fibrate users should probably not receive the drug prescribed. Regulation based on blood cholesterol level encourages the overlooking of other risk factors relevant for selecting patients having the greatest chance to benefit from statin treatment.