Suicidal ideation and attempts in the United States of America among stimulant-treated, non-stimulant-treated, and untreated patients with a diagnosis of attention-deficit/hyperactivity disorder

Abstract

BackgroundStudies of the association between attention-deficit/hyperactivity disorder (ADHD) drug therapy and suicidal ideation and attempts (SIA) have conflicting results. MethodsCohorts of patients with ADHD aged 6 years or older with at least one pharmacy claim for a central nervous system (CNS) stimulant or a non-stimulant, or with no claims for ADHD pharmacotherapy, were identified in the US IBM® MarketScan® Research Database from January 2008 to March 2018. Incidence density rates (IDRs) of SIA (i.e., claims for suicide and self-inflicted poisoning, suicide and self-inflicted injuries, or suicidal ideation) were calculated. Cohorts were compared (CNS stimulants vs non-stimulants; CNS stimulants vs no pharmacotherapy) using hazard ratios (HRs) estimated from Cox proportional hazards models. Inverse-probability-of-treatment weighting (IPTW) was used to control for confounding. ResultsThe study included 797,189 patients (CNS stimulants, 622,536; non-stimulants, 54,615; no pharmacotherapy, 120,038). IDRs of SIA (per 1000 patient-years) were: CNS stimulants, 5.8; non-stimulants, 10.5; and no pharmacotherapy, 10.0. The overall SIA risk was significantly lower with CNS stimulants than with non-stimulants (IPTW-adjusted HR = 0.70, 95% confidence interval = 0.61–0.81, p < 0.001) and no pharmacotherapy (0.62, 0.57–0.67, p < 0.001). LimitationsSIA assessment was based on diagnostic codes; suicidal ideation may not have been reported; completed suicides were generally not captured; and treatment was not verified. ConclusionsIn this population-based study of patients with ADHD, SIA risk was significantly lower in those receiving CNS stimulants relative to those receiving non-stimulants or no pharmacotherapy, suggesting that CNS stimulants may attenuate SIA risk.