Association between frailty and patient outcomes after cancer surgery: a population-based cohort study

Background — Frailty is associated with poor postoperative outcomes, but existing data do not describe frailty's interaction with tumour characteristics at the time of cancer surgery. Our objective was to estimate the association between frailty and long-term survival, and to explore any interaction with tumour stage and grade.

Methods — This was a population-based cohort study conducted using linked provincial health administrative data in Ontario, Canada (2009–20). Using a cancer registry, we identified adults having elective cancer surgery. Frailty was measured using a validated index (range 0–1; higher score=greater frailty). Associations between frailty and long-term postoperative survival (primary outcome) were estimated using proportional hazards regression. Secondary outcomes were length of stay, discharge destination, days alive at home, and healthcare costs.

Results — We identified and included 52 012 patients. Mean frailty score was 0.13 (standard deviation 0.07). During follow-up, 19 378 (37.3%) patients died. After adjustment for risk factors, each 10% increase in frailty was associated with a 1.60-fold relative decrease in survival (95% confidence interval: 1.56–1.64). The frailty–survival association was strongest for patients with lower stage and grade cancers. Increased frailty was associated with longer hospital stays (3 days), fewer days alive and at home (42 days yr−1), more frequent discharge to a nursing facility (2.38-fold), and increased healthcare costs ($6048).

Conclusions — Patient frailty is associated with decreased long-term survival after cancer surgery. The association is stronger for early-stage and -grade cancers, which would otherwise have a better survival prognosis.