Background: Osteoprotegerin (OPG) is a cytokine essential for the regulation of bone resorption, but large longitudinal studies on its relationship to fracture risk in humans are lacking. In this population-based study of 2740 men and 2857 post-menopausal women, it was examined whether serum OPG was associated with hip fracture incidence. The participants were followed for 15 years.
Methods: Baseline measurements included height, weight and serum OPG, and information about lifestyle, prevalent diseases and use of medication.
Results: Men with OPG in the highest quartile were 2.79-fold [95% confidence interval (CI) 1.34-5.82] more likely to have a hip fracture during follow-up, compared with those with OPG in the lowest quartile (P-trend over OPG quartiles ≤ 0.001, after adjustments for age and other confounders). In women not using post-menopausal hormone therapy (HT), the risk of hip fracture was 1.64-fold higher (95% CI 0.94-2.86) in the highest quartile compared with the lowest OPG quartile (P-trend over OPG quartiles = 0.05). No relationship was found in post-menopausal women using HT (P-trend over OPG quartiles = 0.23).
Conclusions: In men, OPG was positively associated with the incidence of hip fracture. In post-menopausal women not using HT a similar, but weaker, relationship was found.