The association of frailty with outcomes and resource use after emergency general surgery: a population-based cohort study

Background — Older patients undergoing emergency general surgery (EGS) experience high rates of postoperative morbidity and mortality. Studies focused primarily on elective surgery indicate that frailty is an important predictor of adverse outcomes in older surgical patients. The population-level effect of frailty on EGS is poorly described. Therefore, our objective was to measure the association of preoperative frailty with outcomes in a population of older patients undergoing EGS.

Methods — We created a population-based cohort study using linked administrative data in Ontario, Canada, that included community-dwelling individuals aged >65 years having EGS. Our main exposure was preoperative frailty, as defined by the Johns Hopkins Adjusted Clinical Groups frailty-defining diagnoses indicator. The Adjusted Clinical Groups frailty-defining diagnoses indicator is a binary variable that uses 12 clusters of frailty-defining diagnoses. Our main outcome measures were 1-year all-cause mortality (primary), intensive care unit admission, length of stay, institutional discharge, and costs of care (secondary).

Results — Of 77,184 patients, 19,779 (25.6%) were frail. Death within 1 year occurred in 6626 (33.5%) frail patients compared with 11,366 (19.8%) nonfrail patients. After adjustment for sociodemographic and surgical confounders, this resulted in a hazard ratio of 1.29 (95% confidence interval [CI] 1.25-1.33). The risk of death for frail patients varied significantly across the postoperative period and was particularly high immediately after surgery (hazard ratio on postoperative day 1 = 23.1, 95% CI 22.3-24.1). Frailty was adversely associated with all secondary outcomes, including a 5.82-fold increase in the adjusted odds of institutional discharge (95% CI 5.53-6.12).

Conclusions — After EGS, frailty is associated with increased rates of mortality, institutional discharge, and resource use. Strategies that might improve perioperative outcomes in frail EGS patients need to be developed and tested.