Thiazolidinediones are associated with a reduced risk of COPD exacerbations

BACKGROUND Thiazolidinediones (TZDs) are oral antihyperglycemic medications that are selective agonists to peroxisome proliferator-activated receptor gamma and have been shown to have potent anti-inflammatory effects in the lung. OBJECTIVE The purpose of this study was to assess whether exposure to TZDs is associated with a decreased risk of chronic obstructive pulmonary disease (COPD) exacerbation. METHODS A cohort study was performed by collecting data on all US veterans with diabetes and COPD who were prescribed oral antihyperglycemic medications during from period of October 1, 2005 to September 30, 2007. Patients who had two or more prescriptions for TZDs were compared with patients who had two or more prescriptions for an alternative oral anti-hyperglycemic medication. Multivariable negative binomial regression was performed with adjustment for potential confounding factors. The primary outcome was COPD exacerbations, including both inpatient and outpatient exacerbations. RESULTS We identified 7,887 veterans who were exposed to TZD and 42,347 veterans who were exposed to non-TZD oral diabetes medications. COPD exacerbations occurred in 1,258 (16%) of the TZD group and 7,789 (18%) of the non-TZD group. In multivariable negative binomial regression, there was a significant reduction in the expected number of COPD exacerbations among patients who were exposed to TZDs with an incidence rate ratio of 0.86 (95% CI 0.81-0.92). CONCLUSION Exposure to TZDs was associated with a small but significant reduction in risk for COPD exacerbation among diabetic patients with COPD.