Epidemiology of abdominal wall and groin hernia repairs in children

Purpose: We sought to estimate the prevalence, incidence, and timing of surgery for elective and non-elective hernia repairs. Methods: We performed a retrospective cohort study, abstracting data on children < 18 years from the 2005–2014 DoD Military Health System Data Repository, which includes > 3 million dependents of U.S. Armed Services members. Our primary outcome was initial hernia repair (inguinal, umbilical, ventral, or femoral), stratified by elective versus non-elective repair and by age. We calculated prevalence, incidence rate, and time from diagnosis to repair. Results: 19,398 children underwent hernia repair (12,220 inguinal, 5761 umbilical, 1373 ventral, 44 femoral). Prevalence of non-elective repairs ranged from 6% (umbilical) to 22% (ventral). Incidence rates of elective repairs ranged from 0.03 [95% CI: 0.02–0.04] (femoral) to 8.92 [95% CI: 8.76–9.09] (inguinal) per 10,000 person-years, while incidence rates of non-elective repairs ranged from 0.005 [95% CI: 0.002–0.01] (femoral) to 0.68 [95% CI: 0.64–0.73] (inguinal) per 10,000 person-years. Inguinal (median = 20, interquartile range [IQR] = 0–46 days), ventral (median = 23, IQR = 5–62 days), and femoral hernias (median = 0, IQR = 0–12 days) were repaired more promptly and with less variation than umbilical hernias (median = 66, IQR = 23–422 days). Conclusions: These data describe the burden of hernia repair in the U.S. The large variation in time between diagnosis and repair by hernia type identifies an important area of research to understand mechanisms underlying such heterogeneity and determine the ideal timing for repair. Level of evidence: Prognosis study II.