Anemia is prevalent among older adults and is associated with increased fracture risk, yet its relationship with bone microarchitecture remains poorly understood. We examined associations between hemoglobin (Hgb) concentrations and compartment-specific bone density, microarchitecture, structure and strength in older males and females. METHODS: This cross-sectional analysis included 126 males and 185 females aged ≥70 years. Hgb quartiles and anemia status (Males: <13 g/dL; Females: <12 g/dL) were measured at baseline. High-resolution peripheral quantitative computed tomography (HR-pQCT) assessed bone parameters at the tibial (T) and radial (R) metaphysis (M) and diaphysis (D). Multiple linear regression models evaluated associations between Hgb quartile and anemia with sex-standardized bone parameters. RESULTS: At the RM, females in higher quartiles of Hgb tended to have the lowest total area (p trend = 0.034) and the highest cortical porosity (p trend = 0.006). In males, higher Hgb was associated with greater TD total volumetric bone mineral density (Tt.vBMD; Q4 vs. Q2: β = 0.67, p = 0.005), but anemia status showed no significant associations. In females, lower Hgb was linked to greater cortical perimeter (Q1 vs. Q2: β = 0.66, p = 0.003) at the TM and greater total area (Q1 vs. Q2: β = 0.71, p = 0.002) at the TM and RD (Q1 vs. Q2: β = 0.59, p = 0.018). Anemic females exhibited greater total area (β = 0.80, p = 0.018) and cortical perimeter (β = 0.75, p = 0.014) but lower Tt.vBMD (β = -0.56, p = 0.022, vs. non-anemic) at the RD. CONCLUSIONS: Hgb levels and anemia status exhibited sex- and site-specific associations with cortical bone structure with more pronounced effects in females. Higher Hgb in males correlated with increased bone density, while in females, it was related to smaller bone areas and more pronounced porosity. These findings suggest cortical bone is more sensitive to Hgb variations than trabecular bone, potentially due to differences in vascularization and oxygen supply.
Sekel et al. (Sat,) studied this question.