Marijuana Use Associated With Higher Functioning In Schizophrenics, Study Says
June 3, 2010 - Manhasset, NY, USA
Manhasset, NY: Schizophrenic patients with a history of cannabis use demonstrate higher levels of cognitive performance compared to patients who have never used the drug, according to clinical trial data published online in the journal Schizophrenia Research.
Investigators at the Feinstein Institute for Medical Research, the Zucker Hillside Hospital in New York, the Albert Einstein College of Medicine, and Princeton University compared the neurocognitive skills of 175 schizophrenics with a history of cannabis use with 280 subjects with no history of illegal drug use.
Researchers reported that cannabis users demonstrated "significantly better performance" compared to nonusers on measures of processing speed, verbal fluency, verbal learning, and memory. Marijuana use was also associated with better over all GAF (Global Assessment of Functioning) scores.
Authors wrote: "The results of the present analysis suggest that [cannabis use] in patients with SZ (schizophrenia) is associated with better performance on measures of processing speed and verbal skills. These data are consistent with prior reports indicating that SZ patients with a history of CUD (cannabis use disorders) have less severe cognitive deficits than SZ patients without comorbid CUD. ... The present findings also suggest that CUD in patients with SZ may not differentially affect the severity of illness as measured by clinical symptomatology."
Researchers speculated that the observed differences in patients' cognitive functioning may be because subjects who use cannabis are more likely to "competently engage in social interaction" than nonusers.
"[T]he present findings suggest that SZ patients with comorbid CUD may represent a higher functioning subgroup of SZ," investigators concluded. "Future large-scale, prospective studies are needed to elucidate the nature of this relationship."
For more information, please contact Paul Armentano, NORML Deputy Director, at: [email protected]. Full text of the study, "Cannabis use disorders in schizophrenia: Effects on cognition and symptoms," will appear in Schizophrenia Research.