Multiple sclerosis and breast cancer risk: a meta-analysis of observational and Mendelian randomization studies

Tian Fang; Zhihao Zhang; Huijie Zhou; Wanchun Wu; Liqun Zou

doi:10.3389/fninf.2023.1154916

Multiple sclerosis and breast cancer risk: a meta-analysis of observational and Mendelian randomization studies

Front Neuroinform. 2023 May 3:17:1154916. doi: 10.3389/fninf.2023.1154916. eCollection 2023.

Authors

Tian Fang¹, Zhihao Zhang², Huijie Zhou¹, Wanchun Wu¹, Liqun Zou¹

Affiliations

¹ Department of Medical Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, China.
² Department of Thyroid Breast Surgery, Xi'an No.3 Hospital, The Affiliated Hospital of Northwest University, Xi'an, Shaanxi, China.

Abstract

Background: Several observational studies have explored the relationships between multiple sclerosis (MS) and breast cancer; however, whether an association exists remains unknown.

Methods: We conducted a meta-analysis of observational studies and Mendelian randomization (MR) based on genetic variants to identify the relationship between MS and breast cancer. The observational studies were searched from PubMed, Embase, Web of Science, and Scopus to assess the relationship between MS and breast cancer from inception to 07 Nov 2022. Moreover, we explored the association between genetically pre-disposed MS and breast cancer risk based on an MR study. The summary analysis for MS from two separate databases [International Multiple Sclerosis Genetics Consortium (IMSGC), FinnGen] and the summary analysis for breast cancer from Breast Cancer Association Consortium.

Results: Fifteen cohort studies involving 173,565 female MS patients were included in this meta-analysis. The correlation between MS and breast cancer was not statistically significant [relative ratio (RR) = 1.08, 95% confidence interval (CI) = 0.99-1.17]. In the MR analysis, we did not observe causal associations of genetically determined MS with breast cancer and its subtypes from both the IMSGC and FinnGen datasets.

Conclusion: The meta-analysis of observational and MR based on genetic variants does not support the correlation between MS and breast cancer.

Keywords: Mendelian randomization; breast cancer; genetic variants; meta-analysis; multiple sclerosis.