|BOSTON - A study by researchers at Johns
Hopkins School of Medicine in New England Journal of Medicine
suggests that the use of beta-blockers, a commonly prescribed medication
for high blood pressure (hypertension), can increase patients' risk of
type 2 diabetes.
Experts at Joslin Diabetes Center say that while the
study results need to be confirmed with further research, the study
could lead physicians to ask patients whether they have a history of
type 2 diabetes in their family or are members of certain ethnic groups
that are at high risk for diabetes. Physicians might one day make
judgments about which blood pressuring lowering medication they
prescribe based on the answers to those questions.
For years research has suggested that thiazide
diuretics and beta-blockers commonly prescribed for high blood pressure
and heart disease may promote development of type 2 (adult-onset)
diabetes, but findings have been inconsistent. High blood pressure
medications are used by more than 20 million adults in the US. Thiazide
diuretics and beta-blockers are generally considered first-line agents
for treating high blood pressure. An estimated 16 million Americans have
diabetes, and many take these medications because they have, or are at
risk for, cardiovascular complications such as heart attack, strokes,
nerve damage, kidney disease, and more.
In the six-year Johns Hopkins' study, 12,550 adults
ages 45-64 who did not have diabetes were studied. Those with high blood
pressure who took beta-blockers had a 28 percent higher risk of
eventually developing type 2 diabetes than did those who took no
medication. In contrast, those who took one of the other types of drugs
used to treat high blood pressure — thiazide diuretic, angiotensin-converting-enzyme
(ACE) inhibitors or calcium-channel antagonists — were found to have no
increased risk of developing diabetes.
Om Ganda, M.D., Senior Physician and lipids specialist
at Joslin Diabetes Center in Boston, generally agrees with the authors'
conclusion that concern about the risk of diabetes should not discourage
doctors from prescribing beta-blockers for adults who do not have
diabetes but who have hypertension. "Beta-blockers may not be the ideal
treatment for all patients who have hypertension, however, particularly
if they have an increased risk for diabetes," Dr. Ganda says. "On the
other hand, beta-blockers have proven beneficial effects in reducing
heart attacks and strokes in people with and without diabetes." Also, he
adds, it is unclear what role the ethnic makeup of the study had on the
outcome and exactly what type of beta-blockers were studied. "It's a
'Catch 22' situation for doctors," Dr. Ganda says.
"But beta-blockers have saved many lives," he says.
Source: Joslin Diabetes Center.