Antibiotics may raise the risk of developing Type 2 diabetes

A new study suggests that taking antibiotics increases the risk of Type 2 diabetes, and the relationship is dose-dependent, according to an article published online August 28, 2015 in the Journal of Clinical Endocrinology & Metabolism.

“In our research, we found people who have Type 2 diabetes used significantly more antibiotics up to 15 years prior to diagnosis compared to healthy controls,” said one of the study’s authors, Kristian Hallundbæk Mikkelsen, MD, of Gentofte Hospital in Hellerup, Denmark. “Although we cannot infer causality from this study, the findings raise the possibility that antibiotics could raise the risk of Type 2 diabetes. Another equally compelling explanation may be that people develop Type 2 diabetes over the course of years and face a greater risk of infection during that time.”

For this population-based case-control study, researchers reviewed records from three national health registries in Denmark to track antibiotic prescriptions for 170,504 people who had Type 2 diabetes and for 1.3 million people who did not have diabetes.

People with Type 2 diabetes filled an average of 0.8 prescriptions a year compared with 0.5 prescriptions a year for control subjects. Individuals who filled more prescriptions were more likely to be diagnosed with Type 2 diabetes.

Although nearly all antibiotics were associated with a higher risk of diabetes, the researchers identified a stronger link with the use of bactericidal and narrow-spectrum antibiotics, such as penicillin V, compared with broad-spectrum and bacteriostatic antibiotics.

The researchers undertook this study because of the accumulating evidence that bacteria in the human gut may influence nutrient metabolism. This may explain why greater antibiotic use is associated with the development of Type 2 diabetes—but more research is needed, the authors wrote.

“Diabetes is one of the greatest challenges facing modern health care, with a globally increasing incidence,” Dr. Mikkelsen said. “Further investigation into long-term effect of antibiotic use on sugar metabolism and gut bacteria composition could reveal valuable answers about how to address this public health crisis. Patterns in antibiotic use may offer an opportunity to prevent the development of the disease or to diagnose it early.”