A new study from Finland has confirmed previous findings about a link between the use of cholesterol-lowering statin drugs and higher risk of Type 2 diabetes.
This study, published in the journal Diabetologia, avoided some of the limitations of earlier research—selective population, size, self-reporting by participants—that limited the applicability of the findings. The new study analyzed the effects of statin use on 8,749 nondiabetic Caucasian men aged 45-73 who were part of the Finland-based Metabolic Syndrome in Men (METSIM) study, Medical News Today reports.
Prof. Markku Laakso of the Institute of Clinical Medicine at the University of Eastern Finland and Kuopio University Hospital explained the limitations of some earlier studies. Some studies had a selective population, for example, people at high risk for cardiovascular disease. These studies often included participants whose diabetes was self-reported or based on their fasting glucose measurements, which may underestimate the actual number of diabetes cases.
In the new study, during a 5.9-year follow-up, 625 men were diagnosed with Type 2 diabetes, determined by either an oral glucose tolerance test (OGTT), an HbA1c level of at least 6.5 percent, or the commencement of anti-diabetic medication. The results of the analysis revealed that men taking statins were at 44 percent higher risk of diabetes than men not taking statins. The 46 percent increased diabetes risk was present even after adjusting for age, body mass index (BMI), waist circumference, physical activity level, smoking, alcohol use, family history of diabetes, and treatment with beta-blockers and diuretic medications, according to Medical News Today.
The researchers assessed changes in insulin resistance and insulin secretion (factors in the disease) among men treated with statins. They found that statins led to a 24 percent reduction in insulin sensitivity, as well as a 12 percent reduction in insulin secretion. For two statins—simvastatin (Zocor) and atorvastatin (Lipitor)—the researchers found the associated risk of Type 2 diabetes was dose-dependent, as were the reductions in insulin sensitivity and insulin secretion among the men taking these drugs. After accounting for the confounding factors listed above, the research team found high-dose simvastatin was linked to a 44 percent higher risk of Type 2 diabetes, while a lower dose was linked to a 28 percent increased risk. High-dose atorvastatin was associated with a 37 percent increased risk of type 2 diabetes.
Among study participants, 53 percent were taking atorvastatin and 29 percent were taking simvastatin, according to Medical News Today. The researchers say, “Statin therapy was associated with a 46% increased risk of type 2 diabetes after adjustment for confounding factors, suggesting a higher risk of diabetes in the general population than previously reported. The association of statin use with increased risk of developing diabetes is most likely directly related to statins decreasing both insulin sensitivity and secretion.”
Though this study avoided certain limitations, it does have limitations. All of the participants were male and Caucasian, meaning that the findings may not be generalizable to women or those of other ethnicities, Medical News Today reports.