Is radiographic vertebral fracture a risk factor for mortality?

Clinical fractures predict increased mortality risk, but few studies report mortality based on prevalent radiographically defined vertebral fracture. This study examined whether radiographically defined vertebral fracture is a risk factor for mortality in older adults. The 1,580 participants in California (631 men, 949 women) were aged >= 50 years in 1992-1996. Lateral spine radiographs, and information about medical history and behaviors, were obtained. Overall, 55 (8.7%) men and 123 (13%) women had at least one prevalent fracture at baseline; of these, 48 women and 14 men had two or more. Over 7.6 years, 460 participants died, 27.6% without and 41.0% with prevalent fractures (p < 0.001). Prevalent vertebral fracture was not associated with all-cause mortality in both sexes combined (adjusted hazard ratio = 1.09, 95% confidence interval: 0.84, 1.42) or sex-specific analyses (women: adjusted hazard ratio = 1.15, 95% confidence interval: 0.83, 1.59; men: adjusted hazard ratio = 0.89, 95% confidence interval: 0.55, 1.46). However, women with two or more prevalent fractures had increased risk of all-cause mortality (adjusted hazard ratio = 1.56, 95% confidence interval: 1.01, 2.40; p = 0.04). Women with any prevalent vertebral fractures also had increased mortality risk from "other" causes (adjusted hazard ratio = 1.59, 95% confidence interval: 1.03, 2.45; p = 0.04) but not cardiovascular disease or cancer. A single radiographic vertebral fracture is not a risk for mortality in older women; larger, longer studies of men and those with two or more radiographic vertebral fractures are needed.