The association between body fat distribution and osteosarcopenia in older adults: evidence from the PoCOsteo study

Osteosarcopenia is a syndrome associated with aging, characterized by the simultaneous occurrence of two conditions: osteopenia and sarcopenia. The association between various fat mass distributions across the body and osteosarcopenia is not clear.

Cross-sectional data from the PoCOsteo study, involving 1,897 participants, were used. T-score was used to define osteopenia. Sarcopenia was identified based on the skeletal muscle mass index (SMI), handgrip strength measurements, and/or a walking speed. Body fat distribution was assessed using Dual X-ray absorptiometry.

Regression models, after adjustment for covariates-age, gender, marital status, tobacco use, income, education, occupation, and hypertension-revealed a negative association between various fat deposits-including total, gynoid, trunk, arm, and android fat-as well as indices of body mass index (BMI) and the trunk-to-limb fat mass ratio, with both osteoporosis and sarcopenia. A significant inverse relationship was also observed between osteosarcopenia and total fat (OR = 0.946, 95% CI: 0.918-0.975), android fat (OR = 0.932, 95% CI: 0.911-0.953), trunk fat (OR = 0.927, 95% CI: 0.903-0.952), and BMI (OR = 0.738, 95% CI: 0.703-0.775).

Osteosarcopenia and its components (osteoporosis and sarcopenia) are inversely associated with BMI and fat mass, particularly in the trunk and android regions.