December 2015Volume 71, Pages 41–47
McLean Hospital, Psychotic Disorders Division, Belmont, MA, Harvard Medical School, United States – a sample of 205 patients recruited from an inpatient psychiatric unit, 40% (n = 82) reported use of stimulants prior to the onset of psychosis in a study titled “Prescription stimulant use is associated with earlier onset of psychosis”.
Highlights from this study included:
- A history of prior exposure to prescription stimulants was associated with an earlier age of onset of psychosis.
- The majority of participants were prescribed stimulants for attention deficit hyperactivity disorder.
- The association between prescription stimulant use and age of onset of psychosis was significant after controlling for potential confounders.
A childhood history of attention deficit hyperactivity disorder (ADHD) is common in psychotic disorders, yet prescription stimulants may interact adversely with the physiology of these disorders. Specifically, exposure to stimulants leads to long-term increases in dopamine release. According to the “British Journal of Nursing,” increased dopamine in the limbic system is linked to suspicious personality, paranoia and withdrawal from social situations. Drugs, such as amphetamines and cocaine, cause buildup of dopamine, which leads to drug-induced psychosis or schizophrenia. In Parkinson’s disease, dopamine-containing cells in the substantia nigra degenerate and die out. Parkinson’s disease patients who are treated with too much L-dopa, a precursor of dopamine, may experience psychosis similar to psychosis seen in schizophrenia.
It was hypothesized that individuals with psychotic disorders previously exposed to prescription stimulants will have an earlier onset of psychosis. Most participants were prescribed stimulants during childhood or adolescence for a diagnosis of ADHD.
AOP (Age of onset of psychosis) was significantly earlier in
those exposed to stimulants (20.5 vs. 24.6 years stimulants vs. no stimulants, p < 0.001).
The study concluded that individuals with psychotic disorders exposed to prescription stimulants had an earlier onset of psychosis, and this relationship did not appear to be mediated by IQ or cannabis.
