Smoking, drinking, and drug abuse are significantly higher among people with psychotic disorders. This is not quite a surprising conclusion, but the hard numbers were generated and given statistical credence by the largest ever study of substance abuse among the population of the mentally ill.
Researchers from the Washington University School of Medicine in St. Louis and the University of Southern California, led by Washington University researcher Sarah M. Hartz, Ph.D., studied nearly 20,000 people, which included 9,142 psychiatric patients diagnosed with schizophrenia, bipolar disorder, or schizoaffective disorder. The study also studied over 10,000 healthy people without mental illness and assessed the incidence of nicotine use, alcohol intake, and use of drugs in this population. The results of the study were published in the online journal JAMA Psychiatry.
The study found that, among the 9,142 mentally ill patients, over 75 percent were regular smokers. Also, about half of those with psychotic disorders smoked marijuana regularly. The use of illicit drugs among the mentally ill was also at 50 percent. These numbers were significantly higher than the numbers tracked in the group of about 10,000 mentally healthy people, with regular smoking at 33 percent, marijuana use at 18 percent, use of illicit drugs at 12 percent. Furthermore, binge drinking in the psychiatrically ill sample was at 30 percent, while only 8 percent of the mentally healthy sample indulged in the habit.
These are disturbing numbers. Hartz said, "These patients tend to pass away much younger, with estimates ranging from 12 to 25 years earlier than individuals in the general population." She further explained that such deaths were caused by heart disease, cancer, and other preventable causes, instead of causes that one might expect in the population of the severely ill, such as drug overdose or suicide.
About 40 percent of mentally healthy people over the age of 50 used to smoke regularly, while fewer than 20 percent of those under 30 years old have been regular smokers. Among the mentally ill, however, the rate is more than 75 percent.
However, smoking rates have declined in the general population during the last few decades. And although smoking used to be permitted in most psychiatric facilities, recent studies unfounded the concerns of many psychiatrists that mentally sick patients must not be burdened with worries about having to quit smoking as well. Instead, Hartz says that the more pressing concern is to find out whether curbing nicotine, alcohol, and substance abuse would actually help lengthen the lives of patients with sever psychiatric illnesses. Hartz further deplores that public health efforts have targeted curbing smoking in the healthy population but "have not made a dent at all" in the severely mentally ill.
Another remarkable finding of the study, according to Hartz, is that race and gender don't have their typical protective influence once a person has already developed a psychotic illness, a phenomenon that holds true especially with the habit of smoking. European Americans as well as men in general tend to have higher rates of substance abuse compared with Hispanics and Asians, and women in general.
The study was funded by the National Institute on Drug Abuse (NIDA), the National Institute on Alcohol Abuse and Alcoholism (NIAAA), the National Institute of Mental health (NIMH), and the National Cancer Institute (NCI) of the National Institutes of Health (NIH), and the American Cancer Society.
