Schizophrenia, Bipolar Disorder Linked With Cancer Risk

Individuals with schizophrenia or bipolar disorder appear to be at an elevated risk of several kinds of cancer, including lung, breast, and colorectal cancer. This startling finding came from a prospective study of more than 3,300 adult Maryland Medicaid recipients with serious mental illness who were followed from 1994 through 2004; study results are published in the July Psychiatric Services. Researchers at Johns Hopkins University and the University of Maryland found that total cancer incidence in the study population was 2.6 times higher than in the general U.S. population. The highest risk was for lung cancer. No differences in risk were found between whites and African Americans in the study cohort, which differs from studies of the general U.S. population, in which African Americans are at higher risk than whites for several types of cancer. The researchers suggest that "High rates of smoking in the population with serious mental illness likely contribute to lung cancer incidence, and research suggests a possible but inconclusive elevated risk of breast cancer due to low rates of childbearing and increased prolactin levels caused by use of particular psychotropic medications. The risk factors contributing to high risk of colon cancer are less understood but may be related to smoking, a sedentary lifestyle, or a diet high in fat and low in fruits and vegetables." Read the complete report of the study in Psychiatric Services. To read interviews with psychiatrists who specialize in treating cancer patients, see Psychiatric News. (image: Lightspring/Shutterstock.com)