["Geriatrics &Gerontology International, Volume 26, Issue 5, May 2026. ", "\nIn older adults without diabetes, higher plasma pentosidine levels are associated with lower skeletal muscle mass and poorer muscle‐related indices. Specifically, elevated pentosidine levels are linked to a reduced skeletal muscle mass index, lower phase angle, and decreased physical performance, with stronger associations observed in women.\n\nABSTRACT\n\nAim\nThis study examined the association between plasma pentosidine concentrations—an advanced glycation end‐product marker—and skeletal muscle morphometric indices, physical function, and sarcopenia among community‐dwelling older adults without diabetes.\n\n\nMethods\nThis cross‐sectional study analyzed data from the 2023 Itabashi Longitudinal Study on Aging in Itabashi Ward, Tokyo, Japan. Participants aged ≥ 70 years were included. Associations between pentosidine concentrations and skeletal muscle morphometric indices and physical function were examined using multiple linear regression adjusted for age, sex, and estimated glomerular filtration rate (eGFR). To explore sex differences, pentosidine × sex interaction terms were tested. Multivariable logistic regression with the same covariates examined associations with impaired physical function, sarcopenia, and severe sarcopenia defined by the Asian Working Group for Sarcopenia 2019 criteria.\n\n\nResults\nAmong 424 participants (mean age 75.7 years; 48.3% women), the mean plasma pentosidine concentration was 5.59 μg × 10−2/mL, with no sex difference. In quartile‐based analyses adjusted for age and eGFR, higher pentosidine concentrations were associated with lower skeletal muscle mass index (SMI) and slower gait speed in women, but not in men. In multivariable analyses adjusted for age, sex, and eGFR, higher pentosidine concentrations were independently associated with lower SMI, lower whole‐body and limb phase angles, and lower short physical performance battery scores. Pentosidine levels were not significantly associated with grip strength, chair rise performance, sarcopenia, or severe sarcopenia. No significant pentosidine × sex interactions were observed.\n\n\nConclusions\nHigher plasma pentosidine concentrations were associated with lower skeletal muscle mass and unfavorable muscle‐related indices in older adults without diabetes. Although stratified analyses suggested stronger associations in women, interaction testing did not support significant sex‐specific effects.\n\n"]