Mental Health | Using methamphetamine within the last 6 months doubled the risk of having psychotic symptoms,
... researchers found in a prospective cohort study published online in Drug and Alcohol Dependence. Longer continuous use was shown to increase the risk even more.
Researchers followed 528 chronic methamphetamine users for 2 years after they left a treatment center in Guangdong, China. Their methamphetamine use and psychotic symptoms (measured with Positive and Negative Syndrome Scale) were assessed every 6 months.
- Data on the 340 patients who completed at least one follow-up were analyzed.
The study team found participants who had used methamphetamine within each 6-month interval were 2.15 times more likely to have had psychotic symptoms, compared with those who had not used it.
In addition, they discovered a dose-response effect between the length of continuous methamphetamine use and the risk of psychotic symptoms. The risk was increased by 2.84 times for participants with 12 months of continued use, and was 9.93 times higher for people with 18 months of continued use.
- There was no measurement of the risk with 24 months of continued methamphetamine use because of the small sample size.
“Longer periods of [methamphetamine] use predicted a higher risk of experiencing psychotic symptoms. Early prevention of [methamphetamine] use could help reduce the risk of psychosis in [methamphetamine] users,” wrote Jun Ma of Peking University in Beijing, China, and colleagues.
