A Cohort Study of Mortality in Individuals With and Without Schizophrenia After Diagnosis of Lung Cancer

Objective: Individuals with serious mental illness have increased mortality relative to those without these illnesses. Although cancer is a leading cause of death, few studies have evaluated potential disparities relative to mortality for individuals with serious mental illness who are diagnosed with cancer. In this study, we evaluated mortality after diagnosis of a common malignancy (lung cancer) in a prototypical serious mental illness (schizophrenia).

Methods: Using administrative data in the Veterans Affairs system, we identified 34,664 individuals who were diagnosed with lung cancer between October 1, 2001, and September 30, 2005. We conducted a survival analysis comparing individuals with and without ICD-9-CM schizophrenia using data through September 30, 2010. Controlling variables were age, gender, smoking status, marital status, service connection, homelessness status, and presence of a substance use disorder.

Results: Our results demonstrated significantly poorer survival after lung cancer diagnosis for individuals with schizophrenia compared to those without schizophrenia. The hazard ratio for all-cause mortality associated with schizophrenia was 1.33 (95% CI, 1.22-1.44).

Conclusions: Individuals with schizophrenia are at higher risk of death after diagnosis of lung cancer than those without schizophrenia. Future studies should further characterize cause of death, quality of cancer care received, and barriers to care.