Higher CALLY index levels indicate lower sarcopenia risk among middle-aged and elderly community residents as well as hospitalized patients.

The C-reactive protein-albumin-lymphocyte (CALLY) index, which integrates albumin, lymphocytes, and C-reactive protein levels, has emerged as a novel method to assess nutritional and inflammatory statuses in patients. This study examined the correlation between the CALLY index and sarcopenia risk using two cohorts: 1804 community dwellers from the NHANES database in the United States and 139 patients from the Department of Gerontology at Kunshan Hospital, China. In the US community cohort, RCS curve analysis was used to examine the non-linear relationship between inflammatory/nutritional markers and sarcopenia, subgroup analysis was also conducted. Logistic regression was employed to evaluate the association between the CALLY index and the risk of sarcopenia in both cohorts. Results demonstrated a significant non-linear relationship between the CALLY index and the risk of sarcopenia (P < 0.001). Elevated levels of the CALLY index are independently linked to a decreased risk of sarcopenia in both community residents (OR = 0.35, 95% CI 0.20-0.57, Q3 CALLY index and OR = 0.26, 95% CI 0.11-0.56, Q4 CALLY index) and hospitalized patients (OR = 0.35, 95% CI 0.12-0.96). This finding identified low CALLY index as a conveniently measurable parameter, serving as a nutritional and inflammatory risk factor for sarcopenia.