Prevalence of mental illness among 70-year-olds domiciled in nine Copenhagen suburbs.

The results of a study on the prevalence of mental diseases and abnormalities among a geographically well-defined group of 70-year-olds, all living in nine suburbs of Copenhagen, are submitted and discussed. The total psychiatric morbidity was found to be 15.5%; 6.4% suffered from psychoses, males preponderating, and 7.4% classified as "neuroses + personality disorders", females preponderating. Only 15% of the pschotic group were institutionalised. Of the entire material, 5% were demented, and this included 1.l% patients who were severley demented. There was a definite preponderance of males. Of the population, 2.6% were living in their homes with senile or arteriosclerotic dementia. About 1% of the population were looked after in their homes despite severe dementia of varying geneses. Hidden morbidity, meaning that the proband had neither been institutionalised nor had consulted a doctor for mental illness within the past 5 years, made up of 15% of the psychotic group and 19.2% of the group "neuroses + personality disorders + alcoholisms". The total hidden morbidity constituted 2.6% of the population or 16.5% of the demonstrated psychiatric morbidity. The prevalence findings are on the whole on a level with those reported from other studies, most of which have been concerned with population groups over 65 years of age.