Objective: To investigate the relationship between osteoporotic vertebral fractures and rosiglitazone treatment and the influence on this association of bone mineral density (BMD) and duration of diabetes.
Research design and methods: In this cross-sectional study, we evaluated BMD by DXA and the prevalence of radiological vertebral fractures identified by a quantitative morphometric analysis in 43 males with type 2 diabetes under metformin alone (22 cases) or associated with rosiglitazone (21 cases) and in 22 control non-diabetic subjects attending an out-patient bone clinic.
Results: Vertebral fractures were found in 46.5% of diabetic males (p=0.06 vs. control subjects) with higher prevalence in patients treated with rosiglitazone plus metformin as compared with those under treatment with metformin alone (66.7% vs. 27.3%; p=0.01). The patients on rosiglitazone plus metformin were significantly younger and with greater body mass index (BMI). Multivariate logistic regression analysis demonstrated that rosiglitazone plus metformin treatment maintained the significant correlation with the occurrence of vertebral fractures (odds ratio 6.5, C.I. 1.3-38.1, p=0.03) even after correction for age and BMI. Within the rosiglitazone-exposed group, the occurrence of vertebral fractures was not correlated with BMD, age, duration of diabetes, duration of medical treatment, dose of rosiglitazone, serum glycosylated hemoglobin and total testosterone values.
Conclusions: The use of rosiglitazone is associated with an increased prevalence of vertebral fractures in males with type 2 diabetes. These findings call for a wide screening of bone status in diabetic patients treated with rosiglitazone and the use of spine X-ray in combination with DXA in this assessment.