Effect of high-potency statins on HbA1c in patients with or without diabetes mellitus

BACKGROUND: The increased risk of new-onset diabetes with statin use, including high-potency statins, is well known. However, the effects of high-potency statins on HbA1c are unclear. A retrospective cohort study was conducted to examine the effect of high-potency statins on HbA1c in patients with or without diabetes. The study enrolled new statin users identified via the electronic healthcare database of the general hospital in Japan. METHODS: Following identification of all individuals (n = 4,672) who had been prescribed a lipid lowering drug at least once between January 1, 2010 and July 31, 2014, new statin users were selected (n = 1,136). Patients were excluded if they had been prescribed treatment with a statin within the preceding 6-month period. HbA1c levels before and during high-potency statin treatment were compared using the dependent t-test. In addition, the hazard ratio for the incidence of diabetes with high-potency statin treatment was estimated, using low-potency statins as a reference. RESULTS: In patients with diabetes (n = 153), mean HbA1c (%) levels significantly increased by 0.4 % after high-potency statin use (7.57 ± 1.58; p = 0.0002) compared to baseline (7.18 ± 1.37). Similarly, HbA1c (%) levels significantly increased from 5.78 ± 0.38 to 5.92 ± 0.45 (p < 0.0001) after high-potency statin use in patients without diabetes (n = 165). Furthermore, a trend toward an increase in HbA1c was found for all of the high-potency statins irrespective of a history of diabetes. CONCLUSIONS: The use of high-potency statins may increase HbA1c levels in patients with or without diabetes.