Montelukast and Neuropsychiatric Events in Children with Asthma: A Nested Case-Control Study.

<bold>Objective: </bold>To examine the association between montelukast prescription and neuropsychiatric events in children with asthma.<bold>Study Design: </bold>A matched, nested case-control design was used to identify cases and controls from a cohort of children aged 5-18 years with physician-diagnosed asthma from 2004 to 2015, in Ontario, Canada, prescribed an asthma maintenance medication. Cases were children with a hospitalization or emergency department visit for a neuropsychiatric event. Cases were matched to up to 4 controls on birth year, year of asthma diagnosis, and sex. The exposures were dispensed prescriptions for montelukast (yes/no) and number of dispensed montelukast prescriptions in the year before the index date. Conditional logistic regression was used to measure the unadjusted OR and aOR and 95% CIs for montelukast prescription and neuropsychiatric events. Covariates in the adjusted model included sociodemographic factors and measures of asthma severity.<bold>Results: </bold>In total, 898 cases with a neuropsychiatric event and 3497 matched controls were included. Children who experienced a new-onset neuropsychiatric event had nearly 2 times the odds of having been prescribed montelukast, compared with controls (OR 1.91, 95% CI 1.15-3.18; P = .01). Most cases presented for anxiety (48.6%) and/or sleep disturbance (26.1%).<bold>Conclusions: </bold>Children with asthma who experienced a new-onset neuropsychiatric event had nearly twice the odds of having been prescribed montelukast in the year before their event. Clinicians should be aware of the association between montelukast and neuropsychiatric events in children with asthma, to inform prescribing practices and clinical follow-up. [ABSTRACT FROM AUTHOR]