Lean Psoas Muscle Area Is Associated with Length of Stay After Lower Limb Revascularization for CLTI.

Background: Chronic limb-threatening ischemia (CLTI) is associated with high morbidity and substantial healthcare utilization. Length of hospital stay (LOS) after lower limb revascularization is influenced by procedural complexity, but patient physiological reserve may also play a role. We evaluated whether CT-derived lean psoas muscle area (LPMA) is independently associated with LOS in patients undergoing revascularization for CLTI. Methods: We retrospectively analyzed 234 consecutive patients treated with endovascular, hybrid, or open revascularization for CLTI (Rutherford 4-5) between 2018 and 2021. Sarcopenia markers were derived from preoperative CT at the L3 level, including psoas muscle area (PMA), muscle density (PMD), and LPMA. Multivariable linear regression models with log-transformed LOS were used to estimate relative effects on hospitalization duration. Results: Median age was 68 years and 65.4% were male; 76.5% of admissions were urgent. Median LOS was 6 days (IQR 4-9). Procedure type was the strongest determinant of LOS: hybrid (β = 0.69, p < 0.001) and open surgery (β = 0.73, p < 0.001) were associated with approximately 99% and 108% longer LOS compared with endovascular treatment. Higher LPMA was independently associated with shorter LOS (β = -0.00049, p = 0.004). Smoking (β = -0.21, p = 0.003) and history of myocardial infarction (β = -0.19, p = 0.030) were associated with shorter LOS, whereas dialysis showed a non-significant trend toward longer hospitalization (β = 0.36, p = 0.056). Conclusions: In patients undergoing lower limb revascularization for CLTI, CT-derived LPMA demonstrated a modest but independent association with hospital stay duration after adjustment for procedural and clinical factors. Given the exploratory nature of this study, these hypothesis-generating findings support further evaluation of imaging-based muscle assessment as an adjunct marker of physiological reserve in this high-risk population.