Study Supports Possible Link of Thiazolidinedione and the Risk for Bone Fracture
Research published September 29, 2009 in PloS Medicine suggests that the thiazolidinedione antidiabetic agents rosiglitazone (Avandia) and pioglitazone (Actos) are associated with an increased risk of fractures. Rezulin (troglitazone), another thiazolidinedione, was withdrawn from the market because of an increased incidence of drug-induced hepatitis. Thiazolidinediones (also known as glitazones) were introduced in the 1990s to treat type 2 diabetes.
A link between thiazolidinediones and an increased risk for bone fracture has been suspected. The large number of people with diabetes and the limited evidence for such a link, however, highlights the need for a better understanding of the risks and benefits of thiazolidinedione treatment.
This need prompted Ian Douglas and fellow epidemiologists at the London School of Hygiene and Tropical Medicine to search the General Practice Research Database, which contains records from more than six million patients registered at nearly 500 primary care practices throughout the United Kingdom.
The researchers then conducted a self-controlled case-series study using data from over 1,800 cases they identified in which subjects aged 40 years or older had received a bone fracture and had been prescribed a thiazolidinedione. They then compared how often the subjects had experienced a bone fracture while they were taking a thiazolidinedione against when they were not taking the medication.
An advantage of this type of study is that it minimizes how differences between people may contribute to the results. Other sources of bias, however, can be greater in this type of observational study than in a randomized trial.
The findings of the study, however, are consistent with those of other investigations that have suggested a link between thiazolidinediones and bone fracture. They also help to further our understanding of the potential risks and benefits of treatment with thiazolidinediones.