Mental illness in a rural area: a Norwegian psychiatric epidemiological study.

Few epidemiological studies have compared less well-integrated urban areas with well-integrated rural areas with the same methods. The aim of this study was to explore the prevalence of mental disorder in a socially stable demographic western region of Norway and make comparison with previously observed prevalence figures of mental illness in Oslo, the capital of Norway. A random sample of the 107,738 residents of Sogn and Fjordane, a western rural region of Norway, age 18-65 years, was drawn from the Norwegian Population Register. A total of 1,080 subjects, 63% of the original sample, were interviewed with the Composite International Diagnostic Interview. The mean age of the subjects was 39.2 years. The 12-month prevalence of mental illness was 16.5% and the lifetime prevalence was 30.9%. Simple phobia and social phobia had the highest 12-month prevalence whereas alcohol abuse and major depression had the highest lifetime prevalence. All mental disorders were more prevalent in women than in men, with the exception of alcohol and drug abuse. Severe psychopathology was found in 2.2% (12 month prevalence) and 5.1% (lifetime prevalence). These observations show that the 12-month and the lifetime prevalence of mental illness in this western area is approximately half the rate of figures observed for Oslo. Epidemiological figures for a western rural region of Norway showing 12-month and the lifetime prevalence of mental disorder are considerably lower than figures obtained in studies from the capital of Norway. However, the same basic pattern of mental illness can be observed in the rural as in the urban area of Oslo, with alcohol abuse/dependence and major depression being the most common disorders at both sites. The sex pattern is also the same with higher figures for women both in rural and urban areas with the exception of alcohol and drug abuse being higher in men.