Vitamin D inadequacy is associated with low-energy distal radius fractures: A case–control study

Abstract

Introduction Vitamin D inadequacy is associated with hip fractures, but the relationship has not been explored for distal radius fractures. Aims To compare serum 25-hydroxyvitamin D (s-25(OH)D) status in low-energy distal radius fracture patients and a group of matched controls, and examine whether observed differences in s-25(OH)D between patients and controls would remain after adjusting for bone mineral density (BMD), body mass index (BMI), and smoking history. Methods A total of 575 female and 72 male low-energy distal radius fracture patients (50–90 years) and 534 female and 52 male matched controls were included. The primary measure was levels of vitamin D. Secondary measures were BMD assessed by dual energy X-ray absorptiometry, BMI and smoking history. Results Mean s-25(OH)D was 66.5 nmol/L in female patients and 78.7 nmol/L in controls ( p < 0.001). The corresponding figures in men were 64.5 and 77.0 nmol/L ( p = 0.017). In adjusted conditional logistic regression analyzes, s-25(OH)D < 50 nmol/L (OR = 2.32, 95% CI: 1.47–3.64, p < 0.001), and 50–75 (OR = 1.70, 95% CI: 1.17–2.47, p = 0.005) were associated with distal radius fractures in women. s-25(OH)D < 50 nmol/L (OR = 6.27, 95% CI: 1.17–33.66, p = 0.032) was associated with distal radius fractures in men. Conclusions Vitamin D inadequacy is associated with low-energy distal radius fractures in both women and men. Differences in vitamin D levels are independent of BMD, BMI or smoking history.