[Suicide deaths among psychiatric patients--a study based on vital statistics]

Utilizing data from the Vital Statistics in 1987 of the Ministry of Health and Welfare, a study was performed to estimate suicide mortality rates among psychiatric in and out-patients. Mental disorder was recorded as being present on 1,755 certifications of suicide deaths (984 men and 771 women). Suicide rate per 100,000 person-years in psychiatric in-patients was 167.3 for males, 116.0 for females. Compared with the general population, this represented an age-standardized mortality ratio (SMR) of 4.5 for males and 5.3 for females. For out-patients the suicide rate was 135.7 for males and 103.7 for females, and the SMR was 4.6 and 5.9 respectively. Considering that the possibility of omission of mental disorders in a death certificate is greater for an out-patient than that for an in-patient, it is concluded that the suicide rate of psychiatric out-patients is greater than that of in-patients.