Mortality in relation to instrumental activities of daily living: one-year follow-up in a Japanese urban community.

One-year mortality among 7,573 elderly residents living in an urban Japanese community was observed in relation to disability in instrumental activities of daily living (IADL). Disability in IADL was assessed for seven items of activity, including using public transportation, using the telephone, and shopping. When the effects of age were controlled, the mortality rate was significantly higher in disabled than in nondisabled persons for all seven items for both males and females.