Diabetes risk from statins may be offset by reduction in cardiovascular events

Atorvastatin, 80 mg/d, carries a higher risk of developing diabetes than do lower doses, but only among patients who already have multiple risk factors, a study found.

Researchers examined data from more than 15,000 patients with coronary disease but without diabetes at baseline in two trials, TNT (Treating to New Targets) and IDEAL (Incremental Decrease in Endpoints Through Aggressive Lipid Lowering). They considered four risk factors that independently predicted new-onset diabetes, including fasting blood glucose above 100 mg/dL, fasting triglycerides above 150 mg/dL, body mass index above 30 kg/m², and history of hypertension. Results appeared in the January Journal of the American College of Cardiology.

Among 8,825 patients with no or one diabetes risk factor at baseline, new-onset diabetes developed in 142 patients in the 80-mg atorvastatin group compared with 148 of those taking 10 mg of atorvastatin or 20 to 40 mg of simvastatin (3.22% vs. 3.35%; hazard ratio [HR], 0.97; 95% CI, 0.77 to 1.22).

Of the 6,231 patients with two to four risk factors, new-onset diabetes developed in 448 of 3,128 in the 80-mg atorvastatin group and in 368 of 3,103 in the lower-dose groups (14.3% vs. 11.9%; HR, 1.24; 95% CI, 1.08 to 1.42; P=0.0027). Researchers noted that cardiovascular events were significantly reduced with 80 mg of atorvastatin in both low- and high-risk groups.

“These results should reassure physicians treating patients at low risk for diabetes,” the authors wrote. “Such patients do not appear to incur an increased risk of diabetes with high-dose atorvastatin and derive benefit in terms of CV [cardiovascular] event reduction. Among the 6,231 patients in the TNT and IDEAL trials at high risk for NOD [new-onset diabetes], treatment with atorvastatin 80 mg compared with a lower statin dose was associated with 80 more cases of NOD and the prevention of 94 major CV events in 58 patients.”

Furthermore, the impact of new-onset diabetes is relatively minor compared to the cardiovascular events included in the study, such as death, myocardial infarction, resuscitated cardiac arrest, and fatal or nonfatal stroke, the authors said.

The authors continued, “In considering the balance between NOD and CV event prevention, it is worth noting that the microvascular and macrovascular complications of diabetes occur relatively uncommonly during the first decade after diagnosis. Many patients with established vascular disease, such as those in this study, will die from an atherosclerotic event before they develop complications from diabetes.”