Time trends in schizophrenia mortality in Stockholm county, Sweden: cohort study.

The Swedish patient register details all psychiatric inpatient treatments since 1 January 1971. Data on residents of Stockholm County (population 1.8 million) whose first admission to hospital with a diagnosis of schizophrenia had occurred between 1976 and 1995 were linked to the national causes of death register, and the date and underlying cause of death were determined in those who had died. Because mortality—and particularly mortality from suicide—is increased in the period after a first admission to hospital, we confined our study to these patients and excluded any who had been diagnosed before 1976. Follow up (in person years) was calculated in relation to sex, five year age group, five year age group and social class, and five year calendar period from the date of a first admission to hospital with schizophrenia to 31 December 1995 or death, whichever occurred first. The expected number of deaths was estimated from mortality rates for the general Stockholm population between 1976 and 1995. Standardised mortality ratios for natural, unnatural, and specific causes of death were calculated for each five year period. Relative excess death risks were estimated through Poisson regression models, controlling for age at diagnosis and length of follow up when appropriate. Standardised mortality ratios for all causes of death increased 1.7-fold in men and 1.3-fold in women over the study period. The increase was greatest in 1991-5 for men and in 1981-5 for women. Death from cardiovascular causes increased 4.7-fold in men and 2.7-fold in women; suicide increased 1.6-fold in men and 1.9-fold in women; and mortality from unspecified violence increased 3.8-fold in men and 3.4-fold in women (table).