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

Background and hypothesis — 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.

Study design — 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.

Study results — 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.

Conclusions — This study did not observe meaningful differences in acute care utilization for asthma exacerbations among children whose biological mothers had schizophrenia.