New research suggests that 17.5 percent of people in China have at least one mental disorder, a figure that is much higher than previously reported estimates of 1.1 percent to 9.1 percent.

The results, reported in The Lancet, also indicate that in the vast majority of cases, the patients have never received any form of professional help for their disorders.

The findings are based on an epidemiologic survey of four provinces in China conducted from 2001 to 2005. In the first stage, 63,004 subjects were randomly selected from an adult population of 113 million and underwent screening with the expanded version of the General Health Questionnaire.

In the second stage, 16,577 individuals - including all subjects deemed to be at high-risk based on the first-stage evaluation, and a random sample of those at moderate or low risk - were evaluated by a psychiatrist.

Mood, anxiety, substance abuse, and psychotic disorders were identified in 6.1 percent, 5.6 percent, 5.9 percent, and 1.0 percent of subjects, respectively, Dr. Michael R. Phillips and colleagues note. Phillips is at the World Health Organization Collaborating Center for Research and Training in Suicide Prevention at Beijing Hui Long Guan Hospital.

Mood and anxiety disorders were more common in women than in men and in subjects 40 years and older. Alcohol use disorders, by contrast, were 48 times more common in men than in women. Subjects who lived in a rural environment were more likely to have a depressive disorder or alcohol dependence than those who lived elsewhere.

Twenty-four percent of individuals with a diagnosable mental illness were moderately or severely disabled by their illness, the report shows. Just 8 percent of subjects with a diagnosable mental disorder had ever sought professionally help and only 5 percent had ever seen a mental health professional.

“Substantial differences (exist) between our results and prevalence, disability, and treatment rate estimates used in the analysis of global burden of disease (in) China. This draws “attention to the need for low-income and middle-include countries to do detailed, country-specific situation analyses before they scale up mental health services,” the authors conclude.

SOURCE: The Lancet, June 13, 2009.