Perhaps you've already heard that the diabetes drugs rosiglitazone (marketed as Avandia®) and pioglitazone (marketed as Actos®) have been linked to an increased risk of heart failure and may increase the risk of bone fractures in patients with type 2 diabetes. Rosiglitazone has also been associated with an increased risk of heart attack. A recent study in the latest issue of the Archives of Internal Medicine reports additional evidence that long-term use of rosiglitazone and pioglitazone may increase the risk of fractures in diabetic patients.

It is thought that thiazolidinedione drugs, such as rosiglitazone and pioglitazone, may cause decreased bone formation and accelerated bone loss. The authors of the study evaluated 1020 diabetic patients between the ages of 20 and 89 who had been diagnosed with a bone fracture between January 1994 and December 2005. After adjusting for age, gender, body mass index, other anti-diabetic drugs, and other medical conditions, they found that patients who had been treated with 12-18 months of thiazolidinedione therapy were 2-3 times more likely to sustain hip and non-spinal fractures than patients who had never used either rosiglitazone or pioglitazone. And, the likelihood of fracture seemed to increase with the dose of the thiazolidinedione drug.

Since it is estimated that rosiglitazone and pioglitazone account for over one-fifth of the oral anti-diabetic drugs prescribed in the United States, the potential impact of these findings should not be underestimated. Although additional confirmatory studies are needed, diabetic patients should discuss the cardiac and bone risks of rosiglitazone and pioglitazone in order to determine the safest and most effective anti-diabetic treatment.