A new study by the Centre for Addiction and Mental Health (CAMH) finds that there may be a link between heavy use of methamphetamines and schizophrenia. The increased risk for schizophrenia was discovered after reviewing the California hospital records of 42,412 patients who were admitted between 1990 and 2000 with a diagnosis of drug dependence or abuse. Scientists at CAMH compared the drug users to a control group of patients with appendicitis and no drug use. The hospital records were studied for readmissions for up 10 years after the initial admission.
Investigators found that people who were hospitalized for meth use and did not have a diagnosis of psychotic symptoms at the start of the study period, had approximately a one and a half to threefold risk of later being diagnosed with schizophrenia, compared with the appendicitis group and those who used cocaine, alcohol or opioid drugs. Notably, the increased risk due to meth use was similar to that of heavy users of cannabis. Meth and other amphetamine-type stimulants are also thought to be the second most widely used class of illicit drugs in the world.
This is the first study to show a potential link between heavy use of methamphetamines and schizophrenia. However researchers caution that these results need to be confirmed through follow-up studies.
For the article abstract, “Methamphetamine Use and Schizophrenia: A Population-Based Cohort Study” published in Psychiatry Online, go to www. psychiatryonline.org.