SARC-F and six modified versions: prognostic role for prolonged hospital stay and 1-year mortality in older inpatients

The Strength, Assistance with Walking, Rising from a Chair, and Falls (SARC-F) questionnaire was proposed to screen sarcopenia. However, its limited sensitivity may compromise its prognostic value. Since its introduction, several adapted SARC-F-based approaches have been proposed, although their ability to predict clinical outcomes among older hospitalized individuals remains underexplored. This study aimed to investigate the prognostic value of SARC-F and six modified versions in a cohort of hospitalized individuals. Cohort study with prospective data collection. Older adults ( N = 236, 69.8 ± 7.5 years old) hospitalized in medical or surgical wards were included. Outcomes of interest were 1-year mortality and prolonged length of hospital stay (LOS). The original SARC-F was applied. Additional adapted approaches were explored: (1) SARC-CalF (including calf circumference, CC); (2) BMI−adjusted SARC-CalF (using BMI-adjusted CC); (3) SARC-F + mid-upper arm circumference (MUAC); (4) SARC-F + age and body mass (SARC-F EBM); (5) SARC-CalF + MUAC; and (6) BMI−adjusted SARC-CalF + MUAC. Suggestive signs of sarcopenia were SARC-F scores ≥ 4, SARC-F EBM scores ≥ 12, and scores ≥ 11 for all other SARC-based approaches. SARC-F EBM was the approach identifying the lowest rate of suggestive signs of sarcopenia (25.9%), while BMI−adjusted SARC-CalF + MUAC identified the highest rate (79.2%). All SARC-F-based approaches were associated with higher odds of prolonged LOS (OR ranged from 2.05 to 3.31). SARC-CalF model had the highest adjusted AUC for LOS prediction (0.64). Except for SARC-F and SARC-F + EBM, all approaches were associated with a higher risk of 1-year mortality (HR adjusted ranged from 2.07 to 11.34). BMI−adjusted SARC-CalF + MUAC exhibited the highest mortality prediction based on the C-index (0.75). Our study demonstrates that all SARC-F-based approaches are linked to prolonged LOS, and almost all approaches were also linked to 1-year mortality. We also introduce the novel BMI−adjusted SARC-CalF + MUAC version, pending future validation.