Individuals diagnosed with psychotic disorders have an earlier onset of psychosis if they have previously been exposed to prescription stimulants, according to new research currently in press in the Journal of Psychiatric Research.
This study raises major public health concerns as the rates of ADHD diagnoses and prescription of stimulants continue to rise. More than five million children between the ages of 3 and 17 were diagnosed with ADHD in 2012. The overall increase in prescription stimulants, as well as the misuse and off-label prescription of these drugs, has also been well documented.
Stimulant-induced psychosis has been observed since Connell’s studies on amphetamines beginning in 1958. While research has continued on the development of psychosis in individuals who abuse illegal stimulant drugs, less is known about the long-term risk of psychosis in children and adolescents prescribed amphetamine and methylphenidate for ADHD.
To test the relationship between prescription stimulants and the onset of psychosis, the researchers recruited 239 individuals from an inpatient facility who had been diagnosed with a psychotic disorder. The researchers then compared previous prescription use of stimulants and the age of onset of psychosis, while controlling for gender, cannabis use, substance abuse, presence of psychosis in immediate family member and level of educational attainment.
Nearly half of the 239 patients reported a history of stimulant use. Prior use of stimulants was significantly more likely in patients who were younger, male, and had a history of cannabis use. Though, the onset of stimulant use was found to precede cannabis use by an average of two and a half years. Most importantly, however, the researchers found a significant correlation between prior stimulant use and an earlier onset of psychosis, even after controlling for potentially confounding factors.
“In this study, we demonstrate the novel finding that prior exposure to prescription stimulants is associated with an earlier onset of psychosis while controlling for potential confounding factors,” the researchers write. “Our sample was largely prescribed stimulants during childhood and adolescence, and the majority of participants were prescribed stimulants for ADHD.”
They conclude: “This is the first study demonstrating an earlier onset of psychosis for medications prescribed for comorbid psychiatric disorders.”
Moran LV, Masters GA, Pingali S, Cohen BM, Liebson E, Rajarethinam RP, Ongur D, Prescription Stimulant Use is Associated with Earlier Onset of Psychosis, Journal of Psychiatric Research (2015), doi: 10.1016/j.jpsychires.2015.09.012. (Abstract)