Maternal Immigrant Status and Mortality in Children With Congenital Heart Disease: A Population‐Based Cohort Study

BACKGROUND: This study examined the association between maternal immigrant status and survival of children with congenital heart diseases (CHD) in Ontario, Canada. METHODS: A retrospective population-based cohort study of hospital live births between April 2002 to September 2020 in Ontario, Canada was conducted at the Institute for Clinical Evaluative Sciences. Multilevel Cox hazard regression models generated hazard ratios (HR) for the association between maternal immigrant status and child death while accounting for hospitals as a cluster factor and adjusting for maternal age at birth, neighborhood income and education quintiles, comorbidities, a composite of severe maternal morbidity, gestational age at birth, birth weight, infant sex and residential rurality among all CHD, severe CHD or single ventricle patients. RESULTS: Among children with any CHD, relative to children born to nonimmigrants, the adjusted HR was 1.17 (95% CI: 1.06-1.30) in children born to nonrefugee immigrants, and 1.33 (95% CI: 1.07-1.65) in those born to refugees. Similar patterns were observed in children with severe CHD, particularly within the single ventricle CHD subcohort, where the adjusted HR for children born to refugees was 2.01 (95% CI: 1.5-2.7) relative to those born to nonimmigrants. CONCLUSION: Health policy decision-makers should prioritize understanding the underlying causes of mortality in these populations to reduce health inequities.