Cholesterol-lowering statin drugs do not reduce the risk of diabetes and might modestly elevate the chances of developing the condition, researchers found in a pooled analysis of trial data.

Contrary to our expectation, lead investigator Dr. Swapnil Rajpathak told Reuters Health, we did not find any benefit of statins on diabetes risk. In fact, there is a suggestion that statins may be associated with increased risk -- which needs to be explored further.

The role of statins in lowering high cholesterol and protecting the heart is well established, but their relationship with diabetes is controversial, Rajpathak of Albert Einstein College of Medicine, New York and colleagues note in the journal Diabetes Care. One Scottish trial reported a small protective effect of statins on diabetes.

To investigate further, the researchers pooled data from this trial and five other randomized placebo-controlled trials of statins involving a total of more than 57,000 adults.

After an average follow-up of 3.9 years, 2,082 participants developed diabetes. When data from the Scottish trial were excluded, there appeared to be a small but significant 13 percent increased relative risk of diabetes developing in those who received statin therapy. When the Scottish trial was included in the analysis, the risk of diabetes with statin therapy was attenuated (6 percent increased risk).

However, the researchers emphasize that there were a number of possible factors that may have influenced the results.

In addition, Rajpathak stressed that the benefits of statins on heart disease by far outweigh any detrimental effects on ... diabetes risk.

In an accompanying editorial, Dr. Christie M. Ballantyne of Baylor College of Medicine, Houston, Texas and colleagues agree, pointing out that if future studies confirm such a connection, Because cardiovascular disease accounts for almost two-thirds of deaths in people with diabetes, the protective effect of statins on this major complication may suffice to support their use despite a potential risk of new-onset diabetes.

SOURCE: Diabetes Care, October 2009.

New York