Secondary osteoporosis and the risk of vertebral deformities in women.

Among an age-stratified sample of 942 Rochester, MN women, the overall prevalence of any vertebral deformity, as assessed by radiographic morphometry, was 21.3 per 100. The prevalence increased with age and, after adjusting for age, vertebral deformities were independently associated with height, weight, a history of distal forearm or hip fractures, and anticoagulant use. Altogether, 73% of the women with a vertebral deformity and 66% of controls had one or more of the conditions that have been linked with secondary osteoporosis, which in aggregate were associated with an age-adjusted 1.2-fold (95% CI 0.8-1.7) increase in risk that was not statistically significant. The prevalence of severe vertebral deformities was 11.7 per 100 women and the prevalence of very severe deformities was 5.7 per 100. There was a stronger relationship of age and most other risk factors with severe vertebral deformities than with isolated mild deformities, suggesting that a subset of mild deformities may not represent actual vertebral fractures. The metabolic disorders linked with secondary osteoporosis were associated with little increase in the risk of severe vertebral deformities, taken together, or of mild deformities. However, in aggregate these conditions were associated with a 2.3-fold increase (95% 1.1-4.8) in very severe vertebral deformities, which points to a role for rapid cancellous bone loss among women with the worst spinal osteoporosis.