Functional dependence versus frailty in gastrointestinal surgery: Are they comparable in predicting short-term outcomes?

Background: Frailty and functional dependence are important factors in assessing preoperative risk. No studies to date have compared frailty with functional dependence as a predictor of surgical outcomes. We sought to compare the impact of frailty and functional dependence on early outcomes after gastrointestinal surgery. Methods: Patients who underwent gastrointestinal surgery were identified using the American College of Surgeons National Surgical Quality Improvement Program database (2012–2015). Propensity score matching analysis was used to separately match dependent and independent patients, and patients with modified frailty index <3 and modified frailty index ≥3 on baseline characteristics. Multivariable logistic regression analysis was used. Postoperative outcomes were compared. Results: Of 765,082 patients, 1.71% were dependent and 1.49% had a modified frailty index score ≥3. Similar outcomes were observed in matched cohorts for those who were dependent and patients with a modified frailty index score ≥3: readmission (15.61% dependent and 15.75% modified frailty index ≥3), overall morbidity (37.91% and 34.81%), serious morbidity (19.06% and 17.06%), mortality (6.73% and 5.43%), and reoperation (7.01% and 6.48%). Dependent and modified frailty index ≥3 patients had similar odds of outcomes on adjusted multivariable logistic analysis and shared 3 of the top 5 indicators for readmission: complication of surgical procedure (11.46% dependent and 11.23% mFI ≥3), intestinal obstruction (10.70% and 7.65%), and organ space surgical site infection (7.93% and 8.65%). Comparable outcomes and reasons for readmission were also obtained for dependent patients and colectomy patients with a modified frailty index score ≥3. Conclusion: Frailty and functional dependence are comparable in predicting postoperative outcomes after gastrointestinal surgery. Functional dependence should be considered an acceptable and practical alternative for preoperative risk stratification in a clinical setting.