Association between maternal schizophrenia and risk of serious asthma exacerbations in childhood

While maternal schizophrenia is linked to chronic childhood medical conditions, little is known about the risk of acute asthma exacerbations among children whose mothers have schizophrenia. This population-based study used health data for all of Ontario, Canada to evaluate whether having a mother with schizophrenia was associated with increased risk of asthma exacerbations. The study cohort included 385,989 children diagnosed with asthma from age 2 years onward, followed from the time of their asthma diagnosis up to a maximum of age 19 years. Children whose biological mother was diagnosed with schizophrenia prior to the child's asthma diagnosis (n = 1407) were compared children whose mother was not (n = 384,582). Study outcomes were asthma-related hospitalization, and separately, asthma-related emergency department (ED) visit, each up to a maximum child age of 19 years. First exacerbations were evaluated using Cox proportional hazards models, and recurrent exacerbations by Andersen-Gill regression, adjusted for covariates. First hospitalization for an asthma exacerbation occurred in 76 (6.9 per 1000 person-years) vs. 19,679 (5.4 per 1000 person-years) children with and without maternal schizophrenia (adjusted hazard ratio [aHR] 1.21, 95 % CI 0.97–1.51). For first asthma-related ED exacerbations, the rates were 25.1 vs. 20.7 per 100 person-years (aHR 1.06, 95 % CI 0.93–1.21). The adjusted rate ratio (aRR) for recurrent hospitalizations for asthma exacerbations was 1.27 (95 % CI 0.98–1.66), and 1.11 (95 % CI 0.94–1.31) for recurrent asthma-related ED exacerbations. This study did not observe meaningful differences in acute care utilization for asthma exacerbations among children whose biological mothers had schizophrenia.