Common comorbidity indices fail to predict short-term postoperative outcomes following male urethroplasty

To evaluate whether commonly used comorbidity indices [Charlson Comorbidity Index (CCI), Van Walraven Index (VWI), and modified frailty index (mFI)] predict postoperative readmissions and complications after urethroplasty.

Patients undergoing urethroplasty for urethral stricture from the State Inpatient Database and State Ambulatory Surgery and Services Database for Florida (2010–2015) and California (2010–2011) were identified. We calculated CCI, VWI, and mFI scores for each patient. We extracted the following adverse outcomes: 30 day ER services, 30 day inpatient readmissions, and 90 day Clavien–Dindo III–V complications. We constructed receiver operating characteristic (ROC) curves and compared area under the curve (AUC), using the VWI as the reference index.

We identified 908 urethroplasty patients. Among these patients, 11.5% (n = 104) of patients had a complication, with 4.8% (n = 44) specifically having 30-day ER services, 6.2% (n = 56) having 30 day readmissions, and 9.0% (n = 82) having 90-day Clavien–Dindo III–V complications. ROC curves demonstrated poor predictive performances for all four indices as no index achieved an AUC > 0.70. The indices performed similarly poorly but the mFI-DX was particularly poor at predicting 90 day Clavien–Dindo III–V complications (AUC = 0.49; 95% CI 0.43–0.55; p < 0.01).

The CCI, VWI, and mFI have poor ability to identify patients who had an adverse event after urethroplasty. Our results support the need for a urology-specific comorbidity index to better identify at-risk patients undergoing urethroplasty.