Age and bone mass as predictors of fracture in a prospective study.

TLDR

The study followed 521 Caucasian women for 6.5 years to examine how radius bone mass predicts fracture risk. Fracture incidence was modeled with a log‑linear regression of age and radius bone mass across person‑years of follow‑up. Incidence rose with age and lower radius bone mass; age better predicted hip fractures while radius bone mass better predicted distal forearm fractures, indicating bone mass is a useful but not sole predictor.

Abstract

To study the effect of bone mass on the risk of fracture, we followed 521 Caucasian women over an average of 6.5 yr and took repeated bone mass measurements at the radius. We observed 138 nonspinal fractures in 3,388 person-yr. The person-years of follow-up and the incident fractures were cross-classified by age and bone mass. The incidence of fracture was then fitted to a log-linear model in age and bone mass. It was found that incidence of fracture increased with both increasing age and decreasing radius bone mass. When subsets of fractures were examined it was found that age was a stronger predictor of hip fractures, whereas midshaft radius bone mass was a stronger predictor of fractures at the distal forearm. We concluded that bone mass is a useful predictor of fractures but that other age-related factors associated with fractures need to be identified.