Elderly Caribbean Hispanic men have lower tibial stiffness and failure load compared to non-Hispanic White and Black...

No data exist comparing racial differences in bone microstructure or mechanical competence using HR-pQCT and micro-finite element analysis (μFEA) in elderly Hispanic, non-Hispanic Black (NHB), and non-Hispanic White (NHW) men. These modalities were utilized to investigate skeletal health in 255 elderly men (age ≥ 65) from a population-based study in New York City: 40.0% Caribbean Hispanic (CH), 35.3% NHW, and 24.7% NHB. Covariate-adjusted (age, BMI, calcium consumption, smoking, diabetes, liver disease, and HIV) results are shown. We also explored the effect of socioeconomic (SE) factors. At the distal tibia, CH men had lower trabecular indices with 9% lower stiffness and failure load (both p < .05) compared to NHW. CH men had smaller cortical area (Ct.Ar) and lower thickness (Ct.Th) compared to NHB, with 11% (p < .05) lower stiffness and failure load. After adjusting for SE, differences in stiffness and failure load between CH and NHW were no longer significant. Comparing NHB to NHW men at the tibia, NHB had lower trabecular indices but greater Ct.Ar, Ct. volumetric bone density (Ct.vBMD) and Ct.Th, with no differences in stiffness and failure load. At the diaphyseal tibia, Ct.Ar and Ct.Th were lower in CH compared to both NHW and NHB men, with 11% and 17% lower stiffness and failure load compared to NHW and NHB (all p < .05). Radial μFEA indices were not different. In conclusion, CH elderly men have lower mechanical competence at the tibia compared to NHW and NHB men, which could result in a greater risk of incident fracture in CH men. Some differences between CH and NHW may be related to modifiable SE factors. Studies assessing HR-pQCT's ability to predict incident fracture and how SE factors affect fracture risk are needed in men of races and ethnicities historically underrepresented in skeletal research.