Patterns and predictors of emergency department visits among older patients after breast cancer surgery: A population-based cohort study.

Objectives: To characterize rates, reasons for, and associated predictors for emergency department (ED) visits after breast cancer (BC) surgery.

Methods: All women over 65 years undergoing curative surgery for non-metastatic incident BC (1998-2012) were identified using Quebec's universal healthcare administrative databases. Reasons for ED visits within 45days of operation were reported. Associated factors were estimated using Cox regression.

Results: Of 24,463 patients, 12.8% had postoperative ED visits. Most frequent reasons were: superficial infection, noninfectious gastrointestinal, trauma or wound (other than breast), noninfectious respiratory, and breast wound disruption. Significant predictors included localized (aHR, 1.24, CI 1.04-1.49) or regional disease (aHR 1.64, CI 1.41-1.92), mastectomy (aHR 1.22, CI 1.10-1.34), each operation before definitive oncologic control (aHR 1.12, CI 1.03-1.21), lower institutional volume (aHR 1.23, CI 1.09-1.38), having 6-10 prescriptions (aHR 1.23, CI 1.15-1.31) or >10 (aHR 1.53, CI 1.33-1.77), benzodiazepine use (aHR 1.09, CI 1.01-1.18), anticoagulant use (aHR 1.29, CI 1.13-1.46), cardiovascular disease (aHR 1.15, CI 1.05-1.26), diabetes (aHR 1.11, CI 1.00-1.24), past hospitalization (aHR 1.25, CI 1.17-1.34), and lower income (aHR 1.12, CI 1.04-1.20).

Conclusion: Identification of risk factors in older patients before BC surgery could help prevent postoperative ED visits.