Premature deaths among individuals with severe mental illness after discharge from long-term hospitalisation in Japan: A naturalistic observation during a 24-year period

Abstract

BackgroundPremature death in individuals with severe mental illness (SMI) in countries without nationally collected data, including Japan, is structurally underreported.AimsTo elucidate excess mortality among individuals with SMI in Japan.MethodWe retrospectively investigated all deaths among users of a non-clinical community-based mental health service provider in suburban Tokyo from 1992 to 2015.ResultsDuring the study period, 45 individuals died among 254 qualified registrants. Deaths were by natural causes in 33 cases (73.3%). The mean years of life lost was 22.2 years and the overall standard mortality ratio (SMR) was 3.28 (95% CI 2.40–4.39). The cause-specific SMR was 5.09 (95% CI 2.33–9.66) for cardiovascular disease and 7.38 (95% CI 2.40–17.22) for suicide.ConclusionsAlthough Japan leads the world in longevity, individuals with SMI suffer premature death and excess mortality due to physical conditions as well as suicide. Revealing this underreported disparity of life is the first step to improving physical care for individuals with SMI.