Do statins interfere with lifestyle intervention in the prevention of diabetes in primary healthcare? One-year follow-up of the FIN-D2D project

Objectives To examine whether the use of statins is associated with the incidence of type 2 diabetes (T2D) and changes in glucose metabolism among individuals at high risk for T2D participating in 1-year lifestyle intervention in primary healthcare setting. Design Prospective follow-up study. Setting In all, 400 primary healthcare centres and occupational healthcare clinics in Finland. Participants We screened altogether 10 149 individuals at increased risk for T2D; of these, 2798 non-diabetic individuals verified by a 2？h glucose tolerance test participated in the 1-year follow-up. Interventions Lifestyle intervention (individual and/or group-based counselling). Primary outcome measures Incidence of T2D and fasting and 2？h glucose measured at baseline and follow-up. Results A total of 484 individuals (17.3%) used statins at the baseline. Of them 31 (7.5%) developed T2D during the follow-up, compared to 126 (6.5%) of statin non-users (OR 1.17, 95% CI 0.78 to 1.76, p=0.442). Interestingly, fasting glucose increased by 0.08？mmol/l in statin users, but remained unchanged in non-users, the difference being 0.074？mmol/l (95% CI 0.014 to 0.134) and remained significant even after adjustment for age, sex, baseline fasting glucose, the presence of cardiovascular disease (CVD), use of antihypertensive and/or coronary artery disease medication, weight and 1-year weight change (adjusted p=0.042). Conclusions The incidence of T2D did not differ between the statin users and non-users. The finding that fasting glucose slightly increased in statin users in spite of lifestyle interventions suggests the view that the use of statins might have unfavourable effects on glucose metabolism and that statins might hamper beneficial effects of lifestyle intervention in people at high risk of T2D