Cancer incidence in a sample of Maryland residents with serious mental illness

Objective: Persons with serious mental illness have an increased mortality rate and a higher burden of many medical conditions compared with persons without serious mental illness. Cancer risk in the population with serious mental illness is uncertain, and its incidence was examined by race, sex, and cancer site in a community-based cohort of adults with schizophrenia or bipolar disorder. Methods: The authors calculated standardized incidence ratios of total and site-specific cancers in a cohort of 3,317 Maryland Medicaid adult beneficiaries with schizophrenia or bipolar disorder followed from 1994 through 2004 for comparison with the U.S. population. Results: Total cancer incidence for adults with schizophrenia or bipolar disorder was 2.6 times higher in the cohort. Elevated risk was greatest for cancer of the lung. No differences in risk were found for African-American versus white Medicaid beneficiaries with serious mental illness. Conclusions: These findings suggest that there is a heightened risk of cancer among adults with schizophrenia or bipolar disorder. Clinicians should promote appropriate cancer screening and work to reduce modifiable risk factors, such as smoking, among persons with serious mental illness.