Beta Blockers Increase the Risk of Developing Diabetes

By: Thomas Pickering, MD, DPhil, FRCP, Director of Integrative and Behavioral Cardiology Program
of the Cardiovascular Institute at Mount Sinai School of Medicine, New York.

Diabetes and hypertension often occur together, particularly in people who are overweight, and the combination of the two can be devastating. One unresolved issue has been whether some of the drugs used to treat high blood pressure, particularly beta blockers and diuretics, actually increase the risk of developing diabetes.

The Atherosclerosis Risk in Communities (ARIC) study is a following a population of nearly 16,000 adults living in four parts of the US. In 12,550 of them who did not have diabetes when first seen, the incidence of new onset diabetes was assessed after six years. About one third of these subjects had hypertension, and they tended to be more obese, older, black rather than white, and have a higher fasting blood sugar.

During the six years of follow-up, the chances of becoming diabetic were analyzed according to what type of blood pressure-lowering medication these subjects were prescribed for treating their hypertension. The main finding was that neither diabetics nor ACE inhibitors had any effect one way or the other, but beta blockers increased the risk of becoming diabetic by 28%. This effect was still seen after controlling for all the other factors likely to be associated with diabetes onset, such as weight gain (in this study beta blockers did not affect body weight).

Doctor’s comments

This study confirmed that there is a strong association between diabetes and hypertension, particularly in people who are overweight. Some previous but much smaller studies have suggested that diuretics can increase the risk of diabetes, and others that ACE inhibitors can decrease it. Here the only drugs that influenced the development of diabetes were beta blockers, and one implication of this finding is that in someone who has hypertension and who is at increased risk of diabetes (a person with a family history of diabetes and central or “beer belly” obesity, for example) drugs such as ACE inhibitors and diuretics are preferable to beta blockers.

Where it was published