Objective: Recent studies demonstrated that a low target low-density lipoprotein cholesterol (LDL-c) level, high LDL-c reduction and high dose of statin therapy increased incident diabetes. This study aimed to explore how statin therapy influences glycemic control in type 2 diabetes mellitus (T2DM).
Methods: Medline, Embase, and Cochrane Central were searched for randomized control trials inT2DM. Trials with target LDL-c levels of ≤2.6 mmol/L or LDL-c reduction of ≥30% were analyzed. Then, we calculated mean differences in glycosylated hemoglobin (HbA1c) and fasting blood glucose via stratified LDL-c level, relative LDL-c reduction and statin dose.
Results: In total, trials involving 6,875 participants (3,619 statins, 3,256 controls) were included. Meta-analysis showed that detrimental effect of intensive LDL-c lowering statin therapy on HbA1c (SMD 0.10%; 95% CI 0.05, 0.15; p = 0.000) was more severe than all statin trials analyzed together (SMD 0.07%; 95% CI 0.02, 0.12; p = 0.005). Stratified analyses revealed that the effects on HbA1c became increasingly significant as target LDL-c level decreased and LDL-c reduction increased. Low baseline LDL-c and endpoint LDL-c levels were risk factors involved in increasing HbA1c level during statin therapy.
Conclusions: Statin therapy worsens the glycemic control of T2DM in target LDL-c level and LDL-c reduction dependent manners.
Keywords: Diabetes; HbA1c; LDL-c; meta-analysis; statins.