Abstract / Summary
Frailty assessment may inform selection for cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS–HIPEC), but its association with hospitalization in functionally selected patients remains uncertain. To evaluate the association of the 5-item modified frailty index (mFI-5) and chronological age with postoperative length of stay (LOS). This retrospective single-centre cohort included 292 patients undergoing index CRS–HIPEC between 2014 and 2024. Multivariable median regression assessed LOS, adjusting for mFI-5 ≥ 2, age, American Society of Anesthesiologists physical status, Peritoneal Cancer Index and calendar year. Logistic regression evaluated LOS > 10 days using unrounded durations. Additional postoperative outcomes were assessed secondarily. Median age was 61.1 years; 31 patients (10.6%) were aged ≥ 70 years and 37 (12.7%) had mFI-5 ≥ 2. Median LOS was 7.4 days, and 50 patients (17.1%) stayed > 10 days. In adjusted analysis, mFI-5 ≥ 2 was not associated with median LOS (difference + 0.03 days; 95% confidence interval [CI] − 0.76 to + 0.81), whereas age showed a small positive association (+ 0.26 days per decade; 95% CI 0.04–0.47). Neither mFI-5 nor age was significantly associated with LOS > 10 days. Among patients with mFI-5 ≥ 2, 31/37 had hypertension and diabetes as their only positive components. The component distribution and functional selection of surgical candidates contextualize the findings. Imprecise estimates for prolonged hospitalization preclude conclusions of equivalent risk. In this selected CRS–HIPEC cohort, mFI-5 ≥ 2 was not independently associated with median LOS, while age showed a small positive association. Interpretation of mFI-5 should consider its component profile and patient selection.