Diabetes-Lipitor Link Isn't Found in Everyone

Diabetes risk from taking statins depends on number of diabetes risk factors

(RxWiki News) Drug treatment can prevent heart problems for those at risk. However, certain drugs may lead to other serious health issues, including diabetes.

Researchers found that higher doses of Lipitor (atorvastatin) - a type of statin drug - may increase the risk of developing diabetes, but only in patients with two or more risk factors of diabetes.

Results showed that higher doses of Lipitor did not increase the rate of diabetes in patients with one or no risk factors but increased the diabetes rates by 24 percent in patients with two to four risk factors.

"Ask your doctor about any Rx risks."

The study was conducted by David D. Waters, MD, of the University of California San Francisco, and colleagues. Previous studies have shown a link between statins (drugs used to control cholesterol) and an increased risk of new-onset diabetes, or new cases of diabetes.

Past research by Dr. Waters and colleagues showed four factors of high blood sugar could predict the risk of new-onset diabetes. These factors included:

  • fasting blood sugar levels, or blood sugar before eating
  • fasting triglycerides, or levels of blood fats before eating
  • body mass index (BMI) - a measure of body fat using height and weight
  • history of high blood pressure

In their current study, Dr. Waters and his fellow researchers found the link between diabetes and statin use may depend on the number of risk factors patients have.

Lipitor is a statin drug marketed by Pfizer. Last month, the patent on Lipitor expired, allowing other companies to produce and sell generic atorvastatin. While a 30-day supply of prescription Lipitor costs around $200, generic atorvastatin can cost $30 to $50 for a 30-day supply.

Among patients with zero to one of the risk factors, there was no difference in diabetes rates between patients taking lower-dose and higher-dose Lipitor. A total of 3.22 percent of higher-dose patients and 3.35 percent of lower-dose patients developed diabetes.

When it came to patients with at least two of the risk factors, Lipitor dosage had an effect on diabetes rates. A total of 14.3 percent of higher-dose patients developed diabetes, while 11.9 percent of lower-dose patients developed the condition.

The researchers did not compare diabetes among patients taking no Lipitor. As such, lower doses of Lipitor may also increase diabetes rates. 

Still, higher doses of Lipitor appeared to greatly reduce the number of heart problems in patients with any number of diabetes risk factors.

The study included 15,056 patients with heart disease but without diabetes. Rates of diabetes were compared between those taking higher-dose Lipitor (80 mg per day) and lower-dose Lipitor (10 mg per day plus 20 to 40 mg of simvastatin, which is sold as Zocor).

Of the 8,825 patients with one or no diabetes risk factors, diabetes developed in 142 of 4,407 patients taking higher-dose Lipitor and 148 of 4,418 patients taking lower doses.

Of the 6,231 patients with two to four risk factors, diabetes developed in 448 of 3,128 patients taking higher-dose Lipitor and 368 of 3,103 patients taking lower doses.

The two trials used for data in this study - Treating to New Targets (TNT) and Incremental Decrease in Endpoints Through Aggressive Lipid Lowering (IDEAL) - were funded by Pfizer.

Dr. Waters reported connections to various pharmaceutical companies, including Pfizer, Bristol-Myers Squibb and Roche.

The study was published in December in the Journal of the American College of Cardiology.

Review Date: 
December 6, 2012