The relationship between the modified frailty index score (mFI-5), malnutrition, body composition, systemic inflammation and short-term clinical outcomes in patients undergoing surgery for colorectal cancer

BACKGROUND: While the current literature suggests an association with frailty and clinical outcomes in patients undergoing surgery for colorectal cancer (CRC), the basis of this relationship is unclear. AIM: Examine the relationship between frailty, malnutrition, body composition, systemic inflammation and short-term clinical outcomes in patients undergoing surgery for colorectal cancer. METHODS: Consecutive patients who underwent potentially curative resection for colorectal cancer, between April 2008 and April 2018, were identified from a prospectively maintained database. Frailty was defined using the modified five-item frailty index (mFI-5). Body composition measures included CT-derived skeletal muscle index (SMI) and density (SMD). Systemic inflammatory status was determined using Systemic Inflammatory Grade (SIG). Outcomes of interest were the incidence of post-operative complications and thirty-day mortality. Associations between categorical variables were examined using χ(2) test and binary logistics regression analysis. RESULTS: 1002 patients met the inclusion criteria. 28% (n = 221) scored 2 or more on the mFI-5. 39% (n = 388) of patients had a post-operative complication (Clavien-Dindo I-IV) and 1% (n = 11) died within thirty days of surgery. On univariate analysis, mFI-5 frailty score, was significantly associated with advanced age (p < 0.001), colonic tumours (p < 0.001), reduced use of neo-adjuvant chemotherapy (p < 0.05), higher BMI (p < 0.05), low SMD (p < 0.001), elevated NLR (p < 0.05), elevated mGPS (p < 0.05), elevated SIG (p < 0.05), incidence of post-operative complications (p < 0.001) and thirty-day mortality (p < 0.05). On multivariate analysis, male sex (p < 0.05), elevated SIG (p < 0.05) and mFI-5 score (p < 0.01) remained significantly associated with the incidence of post-operative complications. mFI-5 frailty was found to remain significantly associated with the incidence post-operative complications in patients who were SIG 0 (p < 0.05). CONCLUSION: mFI-5 frailty score was found to be significantly associated with age, systemic inflammation and post-operative outcomes in patients undergoing potentially curative resections for CRC. Incorporation of an assessment of systemic inflammatory status in future frailty screening tools may improve their prognostic value. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12877-022-03703-2.