Meta-analysis of the Correlation Between Schizophrenia and Breast Cancer

Purpose

To determine the correlation between schizophrenia and breast cancer (BC).

Methods

We searched relevant articles indexed in the PubMed, Embase, and Cochrane Library databases; managed the data in Endnote X7 software; evaluated literature quality by Newcastle-Ottawa quality evaluation criteria; designed tables; and extracted relevant data. The main outcome measure was BC incidence. Effect values were risk ratio and 95% confidence intervals. We used Stata 13.1 software to perform the meta-analysis, choosing a corresponding combination model according to heterogeneity test results and carrying out subgroup analyses in order to better understand the stability of results through sensitivity analysis.

Results

On the basis of 15 studies that assessed patients in different geographic regions, meta-analysis results showed that BC incidence between the exposure group (patients with schizophrenia) and the control group (nonschizophrenia population or general population) had statistical difference (risk ratio = 1.18; 95% confidence interval, 1.05, 1.32), thus showing that BC incidence in patients with schizophrenia is higher than in the nonschizophrenia or general population. Subgroup analysis indicated that gender and geographic region may be sources of the assessed studies' heterogeneity.

Conclusion

The incidence of schizophrenia is positively correlated with BC, and the incidence of BC in patients with schizophrenia is increased to a certain degree. Because of the effects of potential and publication bias, this conclusion needs more high-quality studies to increase the strength of evidence.