Risk of re-operation after outpatient distal hypospadias repair in a large, multistate cohort

Abstract

Repair of distal hypospadias is one of the most common pediatric urology procedures in the US. However, the risk of postsurgical complications has been reported primarily from single-institution and tertiary center studies, with short duration of patient follow-up. The aim of the study was to examine the incidence of re-operation and risk factors for re-operation following outpatient distal hypospadias repair in a large, representative sample of USchildren. A retrospective cohort study of patients aged 0-18 years undergoing single-stage distal hypospadias repair was conducted. Data were obtained from the State Ambulatory Surgery and Services Databases of 9 participating states. Patients who underwent outpatient surgery in 2008-2013 were identified using Current Procedural Terminology (CPT) codes. Patients with records suggesting prior surgery for hypospadias (CPT) were excluded, as were patients who underwent the initial repair <2 years before the end of state data availability. Return outpatient surgery visits across institutions within each of the 9 states were tracked to identify re-operations after the single-stage repair, using CPT codes for surgical treatment of hypospadias complications in 2008-2015. Time-to-event analyses were used to estimate the probability (risk) of re-operation over time and to examine whether patient and institutional characteristics were predictive of re-operation (age, race/ethnicity, health insurance, facility ownership, and institutional volume of hypospadias repair). A total of 4673 children treated across 148 institutions were included. The median follow-up time was 4.1 years (range: 2-7.9). Most patients were <1 year of age at the time of initial repair (53%). The risk of re-operation was 2.6% (95% confidence interval[CI]: 2.1-3.0%) at 1 year and 6.7% (95% CI: 6.0-7.5%) at 5 years after initial repair (Figure). Approximately 13% of re-operation patients had the re-operation at a different institution. None of the patient or institutional factors examined was a significant predictor of the risk of re-operation. In this population-based cohort, the estimated 5-year risk of re-operation following single-stage distal hypospadias repair was 6.7% (95% CI: 6.0-7.5). Most re-operations occurred after the first year, informing long-term expectations about postoperative complications. This study was limited by a lack of data on severity of hypospadias and surgeon characteristicsand the inability to track re-operations outside of the state in which the original repair was performed. Approximately 7% of children undergoing distal hypospadias repair undergo a re-operation within 5 years. None of the factors studied were predictive of re-operations.