THURSDAY, March 26, 2026 (HealthDay News) -- For individuals with attention-deficit/hyperactivity disorder (ADHD), sustained treatment with methylphenidate is not associated with the risk for nonaffective psychosis, according to a study published online March 25 in JAMA Psychiatry.
Colm Healy, Ph.D., from the University of Edinburgh in the United Kingdom, and colleagues estimated the relationship between methylphenidate treatment and the risk for nonaffective psychosis in children and adolescents diagnosed with ADHD in a cohort study using data from multiple national Finnish registries for all 697,289 individuals born from 1987 to 1997.
The researchers found that 69.0 percent of the 3,956 individuals diagnosed with ADHD received methylphenidate at least once. Overall, 5.7 percent of individuals were diagnosed with nonaffective psychosis by a mean age of 22.16 years. Substantial variation was seen in hospital district prescribing propensity (first-year range, 0.07 to 0.30). In the overall ADHD sample, sustained methylphenidate treatment was not associated with the risk for nonaffective psychosis. A reduced risk for nonaffective psychosis was seen among individuals diagnosed in childhood (age younger than 13 years) in secondary analyses (three-year risk difference, −0.24; four-year risk difference, −0.21). For those diagnosed in adolescence, an insufficiently strong instrument precluded the same secondary analyses.
"The fact that early treatment was associated with a lower long-term risk of psychosis suggests these medications may do more than manage symptoms in childhood -- they may also have longer-term protective effects against severe mental illness, though this requires further research," lead author Ian Kelleher, M.D., Ph.D., also from the University of Edinburgh, said in a statement.
Two authors disclosed ties to the biopharmaceutical industry.