Methylphenidate Tx of ADHD May Protect Psychosis in Individuals Diagnosed in Childhood

Background: Attention-deficit/hyperactivity disorder (ADHD) is a common disorder in childhood and adolescence. Stimulants are the gold-standard treatment. Research has suggested that there is an increased risk of psychotic disorders in young individuals who have been treated for ADHD. Unfortunately, these studies had confounding factors, and follow-up studies have shown mixed results. A recent study found no evidence of increased risk of psychosis associated with methylphenidate in the short term. Objective: To investigate the relationship between psychosis risk in the long term and methylphenidate use for the treatment of ADHD. Design: Cohort study. Methods: Data were obtained from various medical registries for individuals born in Finland from 1987 to 1997, diagnosed with ADHD in childhood or adolescence, after January 1, 2003 (following methylphenidate licensing). Registries captured inpatient and outpatient health visits. Individuals were followed up until December 2016. The prim more...