Disorderly conduct: U.S. survey finds high rates of mental illness

Science News, June 11, 2005 by B. Bower

About one in four people develops at least one mental disorder in any given year, and nearly one in two people does so at some time in their lives. Most of the cases are mild, however, and don't require treatment. Those are some of the findings from the latest survey of mental health in the United States.

The national assessment, conducted every 10 years, finds that each year around 1 in 17 people experiences at least one mental disorder so severely that the researchers say it requires immediate treatment. However, most of these people don't seek treatment or they receive poor-quality care, say epidemiologist Ronald C. Kessler of Harvard Medical School in Boston and his colleagues.

The first four papers describing results of the $20 million survey funded by the National Institute of Mental Health in Bethesda, Md., appear in the June Archive, of General Psychiatry. A nationally representative sample of 9,282 people, age 18 or older, granted home interviews between February 2001 and April 2003.

Mental disorders involving anxiety, mood, impulse control, and substance abuse were covered in the first round of reports. These conditions represent chronic illnesses early in life, Kessler's team concludes. Three-quarters of people with these ailments first developed symptoms by age 21, and half did so by age 14.

The findings highlight the need to determine how best to treat mental disorders in children and teenagers, the researchers assert. Moreover, says Kessler, "we need to do a better job of figuring out which of today's mental disorders will become more severe in the future."

Anxiety, disorders, including social phobia and panic disorder, had been experienced by 29 percent of participants at some time in their lives and by 18 percent in the year before being interviewed. For impulse-control disorders, including attention-deficit hyperactivity disorder, those figures were 25 percent and 9 percent, respectively.

Corresponding figures for mood disorders, including major depression and bipolar disorder, were 21 percent and 9.5 percent. Lifetime rates for substance abuse disorders were about 15 percent, and 4 percent of those interviewed had experienced these disorders within the past year.

Among cases of past-year mental disorders, 22 percent were classified as serious because of suicide attempts or severe disruptions to daily life. The team classified about 6 percent of the population as being incapacitated by mental illnesses in the past year. These individuals had typically experienced three or four different mental disorders during their lives.

Only 41 percent of all past-year cases received treatment. About half of those seen by mental-health specialists received adequate treatment, as judged by the researchers, compared with 13 percent of those who sought treatment from nonspecialists.

Most people with mental disorders eventually get some treatment for their illness. However, the lag from initial symptoms to first treatment usually ranged from a few years to more than 2 decades, depending on the disorder.

The new survey contains a wealth of data to test where to draw the line in categorizing cases of mental disorders as serious, comments psychiatric epidemiologist William E. Narrow of the American Psychiatric Association in Arlington, Va. Narrow has criticized two previous national surveys for overstating rates of serious mental illnesses (SN: 2/16/02, p. 102).

The prevalences of anxiety and impulse-control disorders appear a bit high in the new survey, says psychiatrist Robert L. Spitzer of Columbia University. "But for better or worse, this is the best survey of mental disorders that we have," he adds.