Taking several courses of antibiotics is linked to a higher risk of type 2 diabetes, researchers warn today.
The findings could be because of the effect of antibiotics on the digestive system and bacteria in the gut.
Researchers led by Dr Yu-Xiao Yang at the University of Pennsylvania, USA, examined figures on antibiotic prescriptions given to over 200,000 diabetics at least a year before diagnosis, versus antibiotic prescriptions given to 800,000 non-diabetic but otherwise similar patients.
This showed that certain types of antibiotics were linked to type 2 diabetes.
Patients given at least two courses of penicillins, cephalosporines, quinolones and macrolides were at increased risk, and the risk increased with an increasing number of courses, they report in the European Journal of Endocrinology.
Specifically, those prescribed two to five courses of penicillins had an 8% increased risk of diabetes. Those given more than five penicillin courses were at a 23% increased risk.
Among those given two to five courses of quinolones, the risk rose by 15%, and by 37% for those given more than five courses. These figures take into account obesity, smoking history, heart disease and history of infections. Neither anti-viral or anti-fungal drugs affected diabetes risk.
Dr Yu-Xiao Yang said: "While our study does not show cause and effect, we think changing levels and diversity of gut bacteria could explain the link between antibiotics and diabetes risk.
"Over-prescription of antibiotics is already a problem around the world as bacteria become increasingly resistant to their effects. Our findings are important, not only for understanding how diabetes may develop, but as a warning to reduce unnecessary antibiotic treatments that might do more harm than good."
The study is published today (25 March) in the European Journal of Endocrinology.
Yang, Y-X. et al. The effect of past antibiotic exposure on diabetes risk. European Journal of Endocrinology 25 March 2015; doi:10.1530/EJE-14-1163
Leave a Reply