Standard-Dose Statin Therapy Provides Incremental Clinical Benefits in Normocholesterolemic Diabetic Patients

Background: Randomized trials have established statins as an agent for prevention of coronary heart disease (CHD). The purpose of this study was to assess the hypothesis that standard-dose statin therapy has a beneficial effect in normocholesterolemic diabetic patients with CHD. Methods and Results: A prospective, randomized, open, blinded-endpoint trial was conducted from 2002 to 2004 at 55 hospitals in Japan to evaluate the effect of statins on subsequent cardiovascular events. A total number of 1,016 CHD patients (301 patients with type 2 diabetes mellitus [DM] and 715 non-DM patients) with serum total cholesterol levels of 180-240 mg/dl were randomly divided into non-statin and statin treatments. Clinical parameters were comparable between DM and non-DM groups. Serum low-density lipoprotein (LDL)-cholesterol levels were equally decreased after statin treatment in the 2 groups. Statin treatment improved prognosis in both the DM and non-DM groups; however, the number needed to treat (NNT) and relative risk reduction (RRR) were remarkable especially in the DM group (NNT=8, RRR=67%) compared with the non-DM group (NNT=30, RRR=24%). Conclusions: Standard-dose statin therapy provides incremental clinical benefits in DM patients with normal cholesterol levels compared with non-DM patients. The data suggest that DM patients may enjoy the pleiotropic effects of statins, independent of the LDL-cholesterol lowering effects of these agents. (Circ J 2010; 74: 779-785)