Fractures between the ages of 20 and 50 years increase women's risk of subsequent fractures.

Background: Perimenopausal and postmenopausal fractures are well-recognized, strong, independent predictors of subsequent fractures. However, it is unknown whether premenopausal fractures are predictive of postmenopausal fractures.

Objective: To determine whether self-reported fractures sustained before the age of 50 years are associated with fractures after this age.

Subjects And Methods: Cross-sectional study of 1284 women (mean +/- SD age, 73 +/- 4 years) who were 10 or more years' postmenopausal and who were recruited from electoral rolls in Auckland, New Zealand. Detailed information on their fracture, medical, menstrual, alcohol, and smoking histories was obtained using a standardized questionnaire.

Results: Nine percent of the women reported fractures before the age of 20 years; 7%, between the ages of 20 and 50 years; and 29%,after the age of 50 years. Fractures sustained between the ages of 20 and 50 years were associated with a 74% increase in the risk of fractures after the age of 50 years (odds ratio, 1.74; 95% confidence interval, 1.12-2.70), while fractures occurring before the age of 20 years were not (odds ratio, 1.01; confidence interval, 0.66-1.56). Multivariate analysis showed that after bone density, age, maternal history of hip fractures, age at menopause, weight, history of hormone replacement therapy, and smoking and alcohol histories were adjusted for, a history of fractures between the ages of 20 and 50 years remained a significant independent predictor of risk of fractures after the age of 50 years (risk ratio, 1.83; confidence interval, 1.12-2.76).

Conclusions: Any fracture (unrelated to motor vehicle accidents) sustained between the ages of 20 and 50 years is associated with increased risk of fractures after the age of 50 years. Therefore, this is an important clinical risk factor that points to the need for bone density measurement, consideration of lifestyle modification, and antiosteoporosis therapies in these women.