Mortality and the relationship of somatic comorbidities to mortality in schizophrenia. A nationwide matched-cohort study.

Abstract

AIM: We conducted a matched-cohort study to assess mortality in schizophrenia and the relationship of mortality with comorbid somatic conditions and suicide attempts. METHOD: A full-population register-based prospective matched-cohort study was performed including all eligible patients with schizophrenia in Hungary between 01/01/2005 and 31/12/2013. Control subjects were individually matched to patients with schizophrenia at a 5:1 ratio. The principal outcome measure was death due to any reason. A non-parametric approach was used for descriptive statistical purposes, the Kaplan-Meier model for survival analysis, and the Cox proportional-hazards regression model for inferential statistics. RESULTS: Patients with schizophrenia (n=65,169) had substantially higher risk of all-cause mortality than the control subjects (n=325,435) (RR=2.4; P<0.0001). Comorbidities and suicide attempts were associated with significantly increased mortality in both groups. As compared to the controls, 20-year old males with schizophrenia had a shorter life expectancy by 11.5years, and females by 13.7years; the analogous numbers for 45-year old schizophrenics were 8.1 and 9.6years, respectively. CONCLUSIONS: A significant mortality gap - mainly associated with somatic comorbidities - was detected between patients with schizophrenia and individually matched controls. Improved medical training to address the disparity in mortality, and many other factors including lack of resources, access to and model of medical care, lifestyle, medication side effects, smoking, stigma, need for early intervention and adequate health care organization could help to better address the physical health needs of patients with schizophrenia.