Higher fat-to-muscle ratios linked to frailty in UK Biobank
A cross-sectional analysis of 445,317 UK Biobank participants found the strongest regional links between arm fat-to-muscle ratios and frailty.
Limit: Frailty could precede fat–muscle imbalance rather than follow it
Edited by Boris Djordjevic · AgingResearch.News
This cross-sectional observational study included 445,317 UK Biobank participants. Researchers estimated whole-body, trunk, leg and arm fat-to-muscle ratios using bioelectrical impedance, which measures the body’s response to a small electrical current. They assessed frailty using adapted criteria.
Higher ratios were associated with greater odds of frailty in both sexes. Arm ratios showed the strongest regional associations. For each increase of one standard deviation in arm ratio—a measure of variation between participants—frailty odds were 1.86 times as high in men and 2.95 times as high in women. Among 39,782 participants in analyses using proteins to estimate organ age, higher ratios and frailty were also associated with older-than-expected organ ages. The patterns across organs matched most clearly between arm ratios and frailty.
Why it matters
Frailty involves increased vulnerability; this study addresses whether fat–muscle balance offers information about this aspect of later-life health beyond weight relative to height.
Caveats
The cross-sectional design could not establish whether fat–muscle imbalance preceded or caused frailty. Protein-based age estimates were indirect measures of organ aging.
