Sunday, December 20, 2009
News, Health + Fitness
Emory study: Pot-smoking connected with early mental illness
By Christine Foster
A 1980s anti-drug-abuse campaign told U.S. schoolchildren to “just say no” to drugs. However, not all of them do; many of them grow up to say “yes.” Quite a few of them begin a longtime drug habit by trying a gateway drug, usually marijuana.
But according to a new Emory University-led study, marijuana may be a gateway to more than just the use of other drugs—it may also accelerate mental illness.
The study, funded by the National Institute of Mental Health and published in the November issue of the American Journal of Psychiatry, finds that patients being treated for psychosis who had a history of smoking cannabis or “pot” on a daily basis experienced psychotic and pre-psychotic symptoms at earlier ages than those who did not.
Researchers at Emory and Georgia State University analyzed data from 109 hospitalized patients. A review of each patient’s symptoms and in-depth drug history showed first-time psychosis patients were more likely to experience psychotic disorders at much younger ages if they had a history of using marijuana daily.
“The purpose [of the study] was to evaluate a group of young people, aged 18 to 40 years, who were hospitalized for the first evaluation and treatment of a psychotic disorder like schizophrenia,” says Dr. Michael T. Compton of Emory’s Psychiatry and Behavioral Sciences department. “We wanted to determine if an adolescent’s marijuana use, before the onset of their symptoms, may have hastened their disorder, causing it to appear earlier than it would have otherwise.”
Prior studies by other researchers have also suggested that marijuana may trigger an early onset of psychotic symptoms.
“Having a family history of psychosis is also associated with an earlier onset on average,” says Compton, whose primary area of research is schizophrenia.
Another factor associated with an early onset of psychosis is gender. Typically, males who smoke pot daily see psychotic symptoms begin between 18 and 25, and females experience their first symptoms between 25 and 32, says Compton.
The symptoms can include delusional thoughts and hallucinations, such as thinking a government agency is tracking them or hearing voices that do not exist. Compton says the new study provides more supporting data.
“For someone who [already] has a hidden genetic risk for developing schizophrenia, using marijuana—especially heavy use that escalates to a daily basis—may cause an earlier onset [of psychotic disorders],” he says. “This is problematic, because the earlier the disease starts, the poorer the outcome is, on average.”
Dr. Timothy Fong, an assistant clinical professor of psychiatry and director of the Impulse Control Disorders Clinic at the University of California at Los Angeles, also warns that marijuana has been associated with the worsening of mental illnesses.
“Marijuana has never been shown to help these psychiatric problems over time and there is a mountain of research to show that if you smoke marijuana now, then your psychiatric problems are not likely to get better on their own,” Fong writes on the Web site Above the Influence (www.abovetheinfluence.com). ”Actually, they are more likely to get worse.”
The site states that marijuana is addictive, “with more teens in treatment with a primary diagnosis of marijuana dependence than for all other illicit drugs combined,” and has been identified as a factor in learning disabilities, anxiety and panic attacks, and shortened attention span.
Emory’s Compton offers a similar array of negatives.
“First and foremost, the use of marijuana can be associated with a multitude of problem behaviors,” he says, including problems in school and school drop-out rates as well as respiratory system difficulties. And, he says, his research shows that it may cause an earlier onset of psychiatric illnesses in those who are already at risk.
The scariest part, says Compton, is young pot users “usually don’t know that they are at risk.”
SP