Neuropsychiatric adverse side-effects of montelukast in children – a Danish nationwide register study.

Background: Leukotriene receptor antagonist including montelukast, may have neuropsychiatric adverse effects, but findings have been conflicting, also in paediatric patients. Objective: To assess if montelukast exposure in children with asthma is associated with onset of neuropsychiatric adverse events using data from the Danish nationwide health registers. Methods: Children aged 5-17 years with either ≥1 prescription redemption of inhaled corticosteroids or montelukast, or with at least one hospital contact with asthma between January 1, 2010 and December 31, 2018 were included. Outcomes were: use of neuropsychiatric medicine (Outcome 1), and hospital contacts with a neuropsychiatric diagnosis (Outcome 2). All outcomes were assessed at 90 days of exposure to montelukast. Children who used neuropsychiatric medicine at baseline were excluded in assessment of Outcome 1. Results: We identified 193,994 children with asthma. No association was found between initiation of montelukast and Outcome 1 or Outcome 2, respectively (HR (95% CI) = 1.08 (0.97-1.18), p=0.18, and HR (95% CI) = 0.92 (0.77-1.10), p=0.36). Conclusion: Initiating montelukast in children with asthma was not associated with the onset of neuropsychiatric events. Figure 1: Risk of neuropsychiatric conditions associated with montelukast initiation assessed as use of neuropsychiatric medicine and hospital contact with a neuropsychiatric diagnose.