Increased Incidence of Vertebral Fracture in Older Female Hemodialyzed Patients with Type 2 Diabetes Mellitus

Bone disease in hemodialysis (HD) patients with type 2 diabetes mellitus (DM) is characterized by low bone turnover (Inaba M, et al. Am J Kidney Dis 2002; 39:1261-1269), although their bone quality is yet to be determined. The present study was designed to examine whether the prevalence of vertebral fracture in female HD patients with type 2 DM, age 65 years and older, might be increased, and the relation of this fracture to bone mineral density (BMD) determined by dual X-ray absorptiometry (DXA), since few data are available on the effect of DM on bone strength at lumbar spine. The prevalence of vertebral fracture in type 2 DM HD patients was 32.3%, which was greater than that of non-DM HD patients (13.3%) when adjusted for age and HD duration. Logistic regression analysis elucidated the presence of DM and age as independent risk factors for an increased prevalence of vertebral fracture in HD patients. In non-DM HD patients, those with vertebral fracture showed age significantly higher and BMD in either lumbar spine or distal one third of radius significantly lower than the respective value in those without fracture. However, in DM HD patients, neither BMD in lumbar spine nor distal one third of radius was significantly lower in those with vertebral fracture than in those without. Furthermore, age did not differ significantly between DM HD patients with and without fracture. In conclusion, female type 2 DM HD patients, age 65 years and older, showed significantly higher incidence of vertebral fracture than non-DM HD patients. Although age and low BMD emerged as independent risk factors for vertebral fracture in non-DM HD patients, those factors failed to be a risk factor in DM HD patients, suggesting that BMD determined by DXA might not be reliable in assessing bone strength in DM HD patients.