One-Year Changes in Frailty Components After Curative Minimally Invasive Surgery for Colorectal Cancer in Older Patients.

BACKGROUND: Frailty predicts outcomes after colorectal cancer surgery, but postoperative changes remain unclear. We previously reported improvement in FRAIL Scale-based frail/pre-frail status 1 year after curative minimally invasive surgery (MIS). This study examined the components underlying that improvement using the FRAIL Scale and Kihon Checklist (KCL). METHODS: This secondary analysis included patients aged ≥ 70 years who underwent curative MIS for colorectal cancer and had preoperative and 1-year postoperative frailty assessments. Changes in FRAIL Scale and KCL indicators were evaluated using paired analyses. RESULTS: Among 239 patients assessed preoperatively, 141 were included in the paired analysis. Among FRAIL Scale items, only the weight-loss criterion improved significantly (35.8% to 9.5%, p < 0.001). In the KCL, oral function risk improved, whereas physical function risk tended to worsen; houseboundness, cognitive decline, and depressive mood were unchanged. Patients whose FRAIL Scale weight-loss criterion resolved showed a modest 1.2-kg increase (p = 0.038), whereas mean body weight remained unchanged overall. In sensitivity analyses, the improvement in oral function risk persisted after excluding patients with preoperative bowel obstruction (p = 0.014). After excluding patients receiving oxaliplatin-containing adjuvant chemotherapy, physical function risk still tended to increase, and fear of falling remained significantly increased (p = 0.011). CONCLUSIONS: FRAIL Scale improvement was driven mainly by resolution of the weight-loss criterion, with modest weight gain and no clear overall body-weight recovery. KCL changes varied across domains and items, with improvement in some aspects but persistence or worsening in others, supporting a multidimensional interpretation of postoperative recovery in older patients.