People with severe mental illness have significantly higher rates of drinking, drug use and smoking, compared with the general population, a new study finds.
UPI reports the study included almost 20,000 people, about 9,000 of whom had psychiatric disorders such as schizophrenia or bipolar disorder.
People with severe mental illness were about four times more likely to have four or more drinks a day, 3.5 times more likely to use marijuana at least 21 times a year, and 4.6 times more likely to use other drugs at least 10 times in their lives. Patients with severe mental illness were five times more likely to be daily smokers, compared with people who were not mentally ill.
The study found 30 percent of those with severe mental illness engaged in binge drinking, compared with 8 percent among the general population. More than 75 percent of those with mental illness smoked. Half of those with mental illness used marijuana regularly, compared with 18 percent of the general population.
"In the general population, women have lower substance use rates than men, and Asian-Americans have lower substance use rates than white Americans, but we do not see these differences among people with severe mental illness," researcher Dr. Sarah Hartz of Washington University in St. Louis said in a news release. "We also saw that among young people with severe mental illness, the smoking rates were as high as smoking rates in middle-aged adults, despite success in lowering smoking rates for young people in the general population."
The findings appear in the journal JAMA Psychiatry.
"I take care of a lot of patients with severe mental illness, many of whom are sick enough that they are on disability," Hartz said. "And it's always surprising when I encounter a patient who doesn't smoke or hasn't used drugs or had alcohol problems."