Study: Cancer More Common in Schizophrenia Patients
Reported June 24, 2009
(Ivanhoe Newswire) — A new study finds people with schizophrenia die from cancer four times as often as people in the general population. Schizophrenia is associated with an increased incidence of premature death, in part due to a high rate of suicide among individuals with the disease. However, suicide alone does not account for the shortened life expectancy seen in schizophrenia patients.
Beginning in 1993, Prof. Frédéric Limosin of the University of Reims, Robert Debré Hospital, in Reims, France and colleagues conducted an eleven-year study to track cancer incidence in 3,470 schizophrenic patients. The investigators sought to identify characteristics that might help predict which schizophrenic patients are likely to develop cancer.
During the eleven years of the study, a total of 476 patients died (14 percent) — a death rate that was nearly four times that of the general population. Of those, 74 patients died of cancer, making it the second most frequent cause of death behind suicide.
In men with schizophrenia, the risk of death due to lung cancer was significantly higher than that in the general population, but the risk of overall cancer death was not significantly higher. In women, the overall risk of mortality was significantly higher than among the general population. The proportion of patients who were smokers was significantly higher in the study population than in the general population (56.3 vs. 33.0 percent). In female schizophrenic patients, the risk of death due to breast cancer was significantly higher than in the general population.
The authors say possible explanations include delays in diagnosis due to patients paying less attention to symptoms; the difficulty for schizophrenic patients to benefit from optimum treatment; and less compliance to treatment.
Prof. Limosin and his collaborators noted that additional studies should further examine cancer rates in individuals with schizophrenia and should better define the characteristics of tumors that arise in these patients.
SOURCE: CANCER, a journal of the American Cancer Society, June 22, 2009