Objectives: To determine the incidence of distal radius fractures and the characteristics of those fractures and to identify the key risk factors.
Design: Prospective cohort study, mean follow-up of 9.8 years.
Setting: Four clinical centers, one each in Baltimore, Maryland; Minneapolis, Minnesota; Pittsburgh, Pennsylvania; and Portland, Oregon.
Participants: Nine thousand seven hundred four white women aged 65 and older, enrolled in the multicenter Study of Osteoporotic Fractures.
Methods: Five hundred twenty-seven distal radius fractures were confirmed by physician review of radiology reports; characteristics of the fractures were noted. Information was also collected on lifestyle, demographics, bone mineral density (BMD), and clinical and performance measures.
Results: The overall incidence of fracture was 7.3/1,000 person-years. Twenty-seven percent of the fractures were intra-articular; 73% were extra-articular. The independent predictors of fracture were decreased BMD (per 0.1 g/cm(2)) at the distal radius ( relative risk ( RR)=1.8, 95% confidence interval ( CI)=1.6-2.1), a history of recurrent falls ( RR=1.6, 95% CI=1.2-2.0), and having had a previous fracture since age 50 ( RR=1.3, 95% CI=1.1-1.6). Current use of oral estrogen was protective ( RR=0.6, 95% CI=0.4-0.8). For women aged 75 and older, poor cognitive status was also a predictor of wrist fracture. Intra-articular fractures occurred more than twice as frequently in women with diabetes mellitus.
Conclusions: This is the first large long-term comprehensive study of distal radius fractures in older people. The results indicate that factors predictive of distal radius fractures can easily be assessed in routine clinical practice and can identify women at high risk for fracture. Selected preventive strategies could be designed to reduce the incidence of these fractures.