Metabolic Syndrome and the Risk of Breast, Endometrial, and Ovarian Cancer among Postmenopausal Women in the UK Biobank
Abstract
Background:
There is some evidence that metabolic syndrome (MetS) is associated with postmenopausal breast and gynecologic cancer. However, results from previous studies have been inconsistent and varied by the definition of MetS used.
Methods:
Using data from the UK Biobank, the association between MetS, according to three definitions, and the risk of breast, endometrial, and ovarian cancer was assessed among postmenopausal women with serologic biomarker data. Cox proportional hazards regression was used to calculate HRs with 95% confidence intervals (CI), adjusting for a range of confounders.
Results:
In total, 4,791 breast cancers, 820 endometrial cancers, and 582 ovarian cancers were diagnosed. For all definitions, MetS was associated with a higher risk of breast cancer (harmonized definition; HR, 1.11; 95% CI, 1.04–1.19) and endometrial cancer (harmonized definition; HR, 2.18; 95% CI, 1.86–2.55) but not ovarian cancer (harmonized definition; HR, 1.08; 95% CI, 0.88–1.31). Assessment of the individual MetS components revealed that only abdominal obesity was consistently associated with breast cancer, whereas all components were associated with a higher risk of endometrial cancer.
Conclusions:
In this cohort, MetS and all MetS components were individually associated with a higher risk of endometrial cancer, but only abdominal obesity was consistently associated with an increased risk of breast cancer. No associations were observed between MetS and ovarian cancer risk.
Impact:
These findings underline the need for further mechanistic research to clarify potential causal relationships and to better inform public health strategies to address the increasing obesity-related cancer burden, particularly endometrial cancer in postmenopausal women.