Risk Factors for Hospital Readmission Following Noncardiac Surgery: International Cohort Study

To determine timing and risk factors associated with readmission within 30 days of discharge following noncardiac surgery. Hospital readmission after noncardiac surgery is costly. Data on the drivers of readmission have largely been derived from single-center studies focused on a single surgical procedure with uncertainty regarding generalizability. We undertook an international (28 centers, 14 countries) prospective cohort study of a representative sample of adults ≥45 years of age who underwent noncardiac surgery. Risk factors for readmission were assessed using Cox regression (ClinicalTrials.gov, NCT00512109). Of 36,657 eligible participants, 2744 (7.5%; 95% confidence interval [CI], 7.2–7.8) were readmitted within 30 days of discharge. Rates of readmission were highest in the first 7 days after discharge and declined over the follow-up period. Multivariable analyses demonstrated that 9 baseline characteristics (eg, cancer treatment in past 6 months; adjusted hazard ratio [HR], 1.44; 95% CI, 1.30–1.59), 5 baseline laboratory and physical measures (eg, estimated glomerular filtration rate or on dialysis; HR, 1.47; 95% CI, 1.24–1.75), 7 surgery types (eg, general surgery; HR, 1.86; 95% CI, 1.61–2.16), 5 index hospitalization events (eg, stroke; HR, 2.21; 95% CI, 1.24–3.94), and 3 other factors (eg, discharge to nursing home; HR, 1.61; 95% CI, 1.33–1.95) were associated with readmission. Readmission following noncardiac surgery is common (1 in 13 patients). We identified perioperative risk factors associated with 30-day readmission that can help frontline clinicians identify which patients are at the highest risk of readmission and target them for preventive measures.