Importance: Injury is a leading cause of childhood morbidity and mortality worldwide. Serious mental illness (SMI) is a major contributor to the global burden of disease.
Objective: To compare injury event rates in children from birth to 5 years of age among Taiwanese children with and without parents with SMI, including schizophrenia, bipolar disorder, and major depressive disorder.
Design, setting, and participants: This population-based, retrospective cohort study of an 11-year Taiwanese birth cohort used data from the Taiwan National Health Insurance Research Database (covering 99% of Taiwanese citizens), the Maternal and Child Health Database, and birth and death certificate databases. The study included 1 999 322 singletons with Taiwanese citizenship born from January 1, 2004, to December 31, 2014, and followed up from birth to their fifth birthday, December 31, 2014, or the date of death, yielding a total of 7 741 026 person-years. Data analysis was performed from April 20, 2017, to September 24, 2019.
Exposures: Physician-diagnosed parental SMI defined using outpatient and inpatient records from 6 years before the child's birth to 5 years after delivery.
Main outcome and measures: Rates of medically attended injury events, injury hospitalization, and injury death retrieved from outpatient records, inpatient records, and death certificates. Generalized estimating equation for log-linear models estimated injury incidence rate ratios (IRRs) comparing parental SMI-exposed children and unexposed children.
Results: The study cohort included 1 999 322 singletons (52.1% males without parental SMI and 52.2% males with parental SMI). Incidence rates of child injury-related outcomes were higher among children exposed to parental SMI (294.8 injury events per 1000 person-years) compared with children who were unexposed (256.1 injury events per 1000 person-years). After adjustment for sociodemographic factors, children with parental SMI had higher rates of injury events (IRR, 1.14; 95% CI, 1.13-1.15), injury hospitalization (IRR, 1.49; 95% CI, 1.42-1.57), and injury death (IRR, 1.82; 95% CI, 1.38-2.39) compared with unexposed children. The results were confirmed in sensitivity analyses. Appendicitis, a negative control outcome, was not associated with parental SMI (IRR, 1.10; 95% CI, 0.94-1.28). In addition, children with and without parental SMI had similar patterns of preventive health care. The mean (SD) number of prenatal visits was 8.09 (2.50) for children with parental SMI and 8.17 (2.47) among unaffected children. The mean (SD) number of well-child visits was 5.70 (2.24) for children with parental SMI and 5.80 (2.21) among unaffected children.
Conclusions and relevance: In this study, children with parental SMI had increased risk of injury, particularly serious injury. Excess risk may be reduced by providing effective mental health treatment, parenting support, and home safety education to parents with SMI who are raising young children.