Prostate Cancer Incidence Low in Men with Schizophrenia
Possible explanations include genetics, medication effects and decreased sexual opportunities
THURSDAY, Dec. 14 (HealthDay News) -- Although men with schizophrenia often have multiple risk factors for cancer such as poor diet, lack of exercise and a history of alcohol and drug abuse, they have a prostate cancer incidence that is only one-half to three-quarters of what would be expected, according to a report published in the December issue of Urology.
E. Fuller Torrey, M.D., of the Stanley Medical Research Institute in Chevy Chase, Md., searched MEDLINE for all studies of "prostate cancer" or "cancer" and "schizophrenia" and found five studies with age-standardized, site-specific cancer data.
All five studies showed a lower standardized incidence ratio for prostate cancer in patients with schizophrenia compared to men without the psychiatric disorder, with incidence ratios ranging from 0.49 to 0.76.
"The low incidence of prostate cancer in men with schizophrenia takes its place epidemiologically alongside other unexplained anomalies of prostate cancer incidence, specifically those involving race and geography," Torrey writes. "Possible explanations included ascertainment bias; genetic factors; antipsychotic drug effects, either by being cancer protective or decreasing testosterone, or both; and lifestyle differences, such as prolonged hospitalization resulting in a decreased opportunity for heterosexual intercourse."