Sex-Specific Differences in Congenital Diaphragmatic Hernia Mortality

Objective To compare disease severity and mortality differences between female and male patients with congenital diaphragmatic hernia (CDH). Study design We queried the CDH Study Group (CDHSG) database for CDH neonates managed between 2007 and 2018. Female and males were compared in statistical analyses using t tests, chi(2) tests, and Cox regression, as appropriate (P <= .05). Results There were 7288 CDH patients, of which 3048 (41.8%) were female. Females weighed less on average at birth than males (2.84 kg vs 2.97 kg, P < .001) despite comparable gestational age. Females had similar rates of extracorporeal life support (ECLS) utilization (27.8% vs 27.3%, P = .65). Although both cohorts had equivalent defect size and rates of patch repair, female patients had increased rates of intrathoracic liver herniation (49.2% vs 45.9%, P = .01) and pulmonary hypertension (PH) (86.6% vs 81.1%, P < .001). Females had lower survival rates at 30-days (77.3% vs 80.1%, P = .003) and overall lower survival to discharge (70.2% vs 74.2%, P < .001). Subgroup analysis revealed that increased mortality was significant among those who underwent repair but were never supported on ECLS (P = .005). On Cox regression analysis, female sex was independently associated with mortality (adjusted hazard ratio 1.32, P = .02). Conclusion After controlling for the established prenatal and postnatal predictors of mortality, female sex remains independently associated with a higher risk of mortality in CDH. Further study into the underlying causes for sex specific disparities in CDH outcomes is warranted.