Prevalence of intellectual dysfunctioning and its correlates in a community-residing elderly population.

To examine the prevalence of intellectual dysfunctioning and its correlates in community-residing elderly people, a randomly selected sample of 1,405 people aged 65 and over living in Settsu, Osaka, were investigated in October 1992. Data for assessing intellectual dysfunctioning were obtained from 1,364 people (97.1%), excluding 21 clinically demented people (1.5%); 17.6/100, 5.6/100, and 3.3/100 of the population showed minor, moderate, and appreciable intellectual dysfunctioning, respectively, and the prevalence of intellectual dysfunctioning increased with age. By multivariate analyses using logistic regression, age over 75, poor general health, including current medical treatment, and psychosocial conditions such as no participation in social activities, no life worth living (no Ikigai), and anxiety about the future were independent risk factors for intellectual dysfunctioning. We conclude that intellectual dysfunctioning is closely associated with health and psychosocial conditions.