Meta-analysis of natural, unnatural and cause-specific mortality rates following discharge from in-patient psychiatric facilities

Background: People discharged from in-patient psychiatric facilities have highly elevated rates of suicide, and there is increasing concern about natural mortality among the seriously mentally ill. Method: A meta-analysis of English-language, peer-reviewed longitudinal studies of mortality among patients discharged from in-patient psychiatric facilities was conducted using papers published in MEDLINE, PsycINFO or EMBASE (from 1 January 1960 to 1 April 2018) located using the terms ((suicid*).ti AND (hospital OR discharg* OR inpatient OR in-patient OR admit*)).ab and ((mortality OR outcome* OR death*) AND (psych* OR mental*)).ti AND (admit* OR admis* OR hospital* OR inpatient* OR in-patient* OR discharg*).ab. Pooled mortality rates for aggregated natural and unnatural causes, and the specific causes of suicide, accident, homicide, vascular, neoplastic, respiratory, gastrointestinal, infectious and metabolic death were calculated using a random-effects meta-analytic model. Between-study heterogeneity was investigated using subgroup analysis and metaregression. Results: The pooled natural death rate of 1128 per 100 000 person-years exceeded the pooled unnatural deaths of 479 per 100 000 person-year among studies with varying periods of follow-up. Natural deaths significantly exceeded unnatural deaths among studies with a mean follow-up of longer than 2 years, and vascular deaths exceeded suicide deaths among studies with mean period of follow-up of 5 years or longer. Conclusion: Suicide may be the largest single cause of death in the short term after discharge from in-patient psychiatric facilities but vascular disease is the major cause of mortality in the medium- and long-term.