High-Dose Statins May Increase Diabetes Risk

June 21, 2011 -- The strongest doses of cholesterol-lowering statin medications prevent heart attacks and strokes in patients with cardiovascular disease, but they may also modestly increase the risk of developing type 2 diabetes, a new study shows.

The study, a re-analysis of five clinical trials representing nearly 33,000 patients, found that the risk of developing type 2 diabetes increased slightly in patients who were on the most aggressive statin regimens compared to those on less powerful statin doses.

For every 498 patients who took high-dose statins for one year, there was one extra case of diabetes.

At the same time, however, the medications prevented one cardiovascular event such as a heart attack or stroke for every 155 people who took them.

“We found that for every one extra case of diabetes associated with this intensive statin use, you’d prevent approximately three people from having a major cardiovascular event,” says study researcher David Preiss, MRCP, a clinical research fellow at the British Heart Foundation Glasgow Cardiovascular Research Center at the University of Glasgow, in Scotland.

“We’re certainly not saying that people shouldn’t be taking a high-dose statin,” Preiss says. “If you’re somebody who’s at high risk of an event, it’s definitely favorable for you, but what you should be doing is every once in a while getting checked for diabetes.”

The new paper, which is published in the Journal of the American Medical Association, echoes two previous studies that noted an increased risk of type 2 diabetes in patients taking statins compared to those on a placebo.

“The evidence is strong that high doses of statins do slightly increase the risk of diagnosis of diabetes,” says Steven Nissen, MD, a cardiologist who is chair of the department of cardiovascular medicine at Cleveland Clinic, in Ohio. “However, the evidence is equally strong that patients on high doses have a reduction in cardiovascular events.”

High-Dose Statins and Diabetes

For the study, researchers solicited unpublished data from five studies that compared high and moderate doses of statins in 32,752 patients with either stable cardiovascular disease or a recent history of chest pain or heart attack. None of the patients had diabetes at the start of the study.

High-dose statins were 80 mg daily doses of Zocor, which is sold generically as simvastatin, or Lipitor.

Moderate-dose regimens varied but included daily doses of 10 mg to 40 mg of simvastatin, Lipitor, or pravastatin, which is also sold as Pravachol.

After being followed for an average of nearly five years, 2,749 patients developed diabetes -- 1,449 in the high-dose group and 1,300 of those on the moderate dose.

Over that same time period, about 20%, or 6,684 study participants, suffered a major cardiovascular event -- 3,134 on the intensive-dose therapy and 3,550 who were taking moderate statin doses.