Life Expectancy, Mortality Risks and Cause of Death in Patients with Serious Mental Illness: A Comparison between 2008-2012 and 2013-2017

Abstract

Background: People with serious mental illness have a significantly shorter life expectancy than the general population. This study investigates whether the mortality rate in this group has changed over the last decade. Method: Using Clinical Record Interactive Search (CRIS) software, we extracted data from a large electronic database of patients in South East London. All patients who had received a diagnosis of schizophrenia, schizoaffective disorder or bipolar affective disorder from 2008-2012 and/or 2013-2017 were included. Estimates of life expectancy at birth, standardized mortality ratios and causes of death were obtained for each cohort according to diagnosis and gender. Comparisons were made between cohorts and with the general population using data obtained from UK Office of National Statistics. Findings: 26,005 patients with serious mental illness were included. In men, life expectancy was greater in 2013-2017 (64.9 years; 95% CI: 63.6-66.3) than in 2008-2012 (63.2 years; 95% CI: 61.5-64.9). Similarly, in women, life expectancy was greater in 2013-2017 (69.1 years; 95% CI: 67.5-70.7) than in 2008-2012 (68.1 years; 95% CI: 66.2-69.9). The difference with general population life expectancy fell by 0.9 years between cohorts in men, and by 0.5 years in women. In women with SMI, cancer was the leading cause of death in 2013-2017, whereas the leading cause in 2008-2012 was cardiovascular diseases. In men with SMI there were more deaths due to cancer in 2013-2017 than in 2008-2012. Cancer overtook cardiovascular disease as the leading cause of death in women. Interpretations: Relative to the general population, life expectancy for people with serious mental illness it is still much worse though appears to be improving. The increased cancer-related mortality in these patients suggests that physical health monitoring should consider including cancer as well as cardiovascular and metabolic disease. Funding Statement: EC is funded by a National Institute for Health Research Doctoral Research Fellowship (NIHR300273). CK was funded by Taipei City Government. RP is funded by National Institute for Health Research. Academy of Medical Sciences, The Wellcome Trust, MRC, British Heart Foundation, Arthritis Research UK, the Royal College of Physicians and Diabetes UK. Declaration of Interests: All authors have completed the ICMJE uniform disclosure form and declared no interest of conflicts. Ethics Approval Statement: The SLaM BRC Case Register and CRIS have received ethical approval as an anonymised data set for secondary analyses from the Oxfordshire Research Ethics Committee C (18/SC/0372). The Clinical Data Linkage Service was used for data protection, linkage and extraction.