Effect of stage, comorbidities and treatment on survival among cancer patients with or without mental illness

Abstract

Background Earlier research suggests poorer outcome of cancer care among people with severe mental illness (SMI). Aims To assess the effect of stage at presentation, comorbidities and treatment on differences in survival among cancer patients with and without a history of SMI in Finland. Method The total population with a first cancer diagnosis in 1990-2013 was drawn from the Finnish Cancer Registry. Hospital admissions because of SMI and deaths were obtained from administrative registers. We calculated Kaplan-Meier estimates and Cox regression models to examine survival differences. Results We found excess mortality in people with a history of psychotic and substance use disorders. Cancer stage and comorbidity did not explain mortality differences. Controlling for cancer treatment decreased the differences. The mortality gap between patients with psychosis and cancer patients without SMI increased over time. Conclusions integrated medical and psychiatric care is needed to improve outcomes of cancer care among patients with SMI. Declaration of interest None.