Association Between Abdominal Obesity and Subsequent Vertebral Fracture Risk.

BACKGROUND:Obesity had been previously considered to be a protective factor against osteoporosis or fractures; however, recent research indicates that obesity, especially abdominal obesity, may increase the risk of some types of fractures. OBJECTIVE:We explored the effects of abdominal obesity on subsequent vertebral fracture (SVF) after percutaneous vertebral augmentation (PVA). STUDY DESIGN:A prospective observational cohort study. SETTING:Department of Spinal Surgery of a hospital affiliated with a medical university. METHODS:A total of 390 women and 237 men aged > 50 years suffering from osteoporotic vertebral fracture (OVF) were included. Weight, height, bone mineral density (BMD), abdominal circumference, and other basic information were measured at baseline and 1-year follow-up visit. RESULTS:During follow-up, 80 (33.7%) men and 143 (36.7%) women incurred SVF. Greater waist circumference (WC) and waist-to-hip ratio (WHR) increased the risk of SVF in men (WC: HR 1.83, P = 0.016; WHR: HR 1.63, P = 0.045) and women (WC: HR 2.75, P = 0.001; WHR: HR 2.63, P = 0.001) after adjustment for BMD and other potential confounders. Compared with normal BMI, being overweight was associated with lower SVF risk (women: HR 0.55, P = 0.044; men: HR 0.46, P = 0.046), and obesity was associated with greater SVF risk (women: HR 4.53, P < 0.001; men: HR 3.77, P < 0.001) in both genders. We observed a nonlinear relationship between BMI and SVF with a U-shaped curve; after adjusting BMD, this became a reverse J-curve. LIMITATIONS:There was no further statistical analysis of the relationship between abdominal obesity and other fracture sites. Asymptomatic SVF may underestimate the impact of abdominal obesity on the occurrence of SVF. CONCLUSIONS:Abdominal obesity was significantly associated with a higher risk of SVF after PVA. Management of body type after PVA may be an effective prevention strategy against SVF.