Association of schizophrenia with the risk of breast cancer incidence a meta-analysis

Abstract

IMPORTANCE Patients with schizophrenia are considered to have many risk factors for the development of cancer. However, the incidence of breast cancer in women with schizophrenia compared with the general population remains uncertain. OBJECTIVE To perform an updated meta-analysis to evaluate the association between schizophrenia and the risk of breast cancer. DATA SOURCES A systematic search of the PubMed and EMBASE databases was conducted using the search terms schizophrenia, schizophrenic, psychosis, combined with breast and cancer, tumor, neoplasm, or carcinoma. The final literature search was performed on August 15, 2017. STUDY SELECTION Cohort studies reporting the standardized incidence ratio (SIR) for the risk of breast cancer in women with schizophrenia compared with the general population. DATA EXTRACTION AND SYNTHESIS The meta-analysis adhered to Meta-analysis of Observational Studies in Epidemiology and the Cochrane Handbook for Systematic Reviews of Interventions. Data extraction was performed independently. A random-effects model was used to pool the results, and a recently proposed prediction interval was calculated to describe the heterogeneity. MAIN OUTCOMESAND MEASURES The SIR for the risk of breast cancer in women with schizophrenia compared with the general population or those without schizophrenia. RESULTS Twelve cohorts including 125 760 women were included in this meta-analysis. The results of the meta-analysis showed that schizophrenia was associated with a significantly increased risk of breast cancer incidence in women (SIR, 1.31; 95% CI, 1.14-1.50; P