Elevated ferritin and circulating osteoprotegerin levels as independent predictors of hip fracture in postmenopausal women admitted for fragility fracture: time for new screening strategies?

Abstract

Identification of risk factors may help us to understand the pathogenesis of osteoporotic hip fracture as well as to formulate development of better diagnostic, prevention and treatment strategies. The present study was designed to determine the impact of multiple metabolic risk factors such as markers of systemic inflammation (C-reactive protein), immune responses-acute phase reactants (ferritin), insulin resistance (HOMA-IR) and bone remodeling (osteoprotegerin), for the prediction of hip fractures in postmenopausal osteoporotic women. The study group consisted of 115 postmenopausal women divided into two groups: Group 1 consisted of 49 women hospitalized in the Orthopedic Department, Wolfson Medical Center for the diagnosis of non-traumatic hip fracture and Group 2 contained 66 postmenopausal osteoporotic women without a history of hip fracture. Metabolic parameters were determined. Circulating OPG was significantly higher in Group 1 than in Group 2 (205.2±177.1 vs 60.0=/-22.3, p<0.0001). While levels of hemoglobin (Hbg) as well as MCV and MCH did not differ between groups, circulating ferritin was significantly increased in Group 1 compared to the control Group 2 (217.9±195.1 vs 49.7±31.3, p<0.0001). In multiple linear regression analysis, which explains about 40% of the variability in CRP, 42% in OPG, and 28% in ferritin, significant by-group differences in terms of these parameters persisted even after adjustment. Elevated serum ferritin concentrations and bone remodeling marker, osteoprotegerin, are independent predictors of hip fracture in postmenopausal women hospitalized for fragility fracture.