Phalangeal bone mineral density predicts incident fractures: a prospective cohort study on men and women—results from the Danish Health Examination Survey 2007–2008 (DANHES 2007–2008)

Abstract

This prospective study investigates the use of phalangeal bone mineral density (BMD) in predicting fractures in a cohort (15,542) who underwent a BMD scan. In both women and men, a decrease in BMD was associated with an increased risk of fracture when adjusted for age and prevalent fractures. The aim of this study was to evaluate the ability of a compact and portable scanner using radiographic absorptiometry (RA) to predict major osteoporotic fractures. This prospective study included a cohort of 15,542 men and women aged 18–95 years, who underwent a BMD scan in Danish Health Examination Survey 2007–2008. BMD at the middle phalanges of the second, third and fourth digits of the non-dominant hand was measured using RA (Alara MetriScan®). These data were merged with information on incident fractures retrieved from the Danish National Patient Registry comprising the International Classification of Diseases (ICD-10). Follow-up was 27–45 months. Major osteoporotic fractures (vertebral fractures, humerus fractures, forearm fractures and hip fractures) were used in the analyses. Fracture events were calculated as "persons with fracture" and evaluated using survival analysis. A total of 307 (1.98 %) of the participants had experienced a new fracture during follow-up. BMD was significantly lower in subjects with fracture (0.32 vs. 0.34 g/cm(2); p < 0.001 adjusted for age, gender, prevalent fractures, height, weight and smoking). In both women and men, a 1 SD decrease in BMD (T score units) was associated with an increased risk of fracture when adjusted for age and prevalent fractures (women: HR = 1.39, CI 1.24–1.54, p < 0.001; men: HR = 1.47, CI 1.20–1.79, p < 0.001). Phalangeal BMD as measured using RA predicts the incidence of major osteoporotic fractures.