Older men with anemia have increased fracture risk independent of bone mineral density

Abstract

Context: Extremely low hemoglobin (Hgb) values have been linked to increased fracture risk at different sites. However, careful assessment of clinically defined anemia and fracture risk is lacking. Objective: To determine whether men with anemia were at increased risk of fracture after accounting for bone mineral density (BMD) and bone loss. Design: Cross-sectional analysis (at visit 3) and prospective analysis (from baseline to visit 3) in the Osteoporotic Fractures in Men (MrOS), a multisite, longitudinal cohort study. Setting: Six communities in the United States. Participants: A total of 3632 community-dwelling men (age 65 years) in MrOS at baseline (2000 through 2002) who were able to walk unassisted, did not have hip replacement or fracture, and had complete blood cell counts at visit 3 (2007 through 2009). Outcomes: Adjudicated spine and nonspine fractures during a median 7.2 years of follow-up. Results: Analytic baseline characteristics associated with fractures or anemia (defined as Hgb,12 g/dL) were included in multivariable models. Anemia was associated with increased risk of any fracture [hazard ratio (HR), 1.67;95%confidence interval (CI), 1.26 to 2.21] and nonspine fracture (HR, 1.70;95% CI, 1.25 to 2.31). A model including change in BMD slightly attenuated the association with any (HR, 1.60; 95% CI, 1.20 to 2.13) and nonspine fractures (HR, 1.57; 95% CI, 1.14 to 2.15). Including absolute BMD did not significantly alter the anemia-fracture association. Anemia was not associated with spine fracture. Conclusions: Community-dwelling older men with anemia had a 57% to 72% increase in nonspine fracture risk independent of BMD and bone loss.