Introduction:
Cardiometabolic syndrome consists of a cluster of metabolic dysfunctions such as impaired glucose tolerance, insulin resistance, dyslipidemia, central adiposity, and hypertension. According to the latest estimates, globally, nearly 25% of all adults have cardiometabolic syndrome. Both cardiometabolic syndrome and cancer pathophysiology commonly involve inflammation and oxidative stress. The objective of this systematic review was to evaluate existing evidences that support the association between cardiometabolic syndrome and risk of developing cancer.
Methods:
We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and Scopus for relevant articles published from the database inception until October 2019. We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines for this review. Using the Oxford Center for Evidence-Based Medicine guidelines individual studies were evaluated. A total of 59 articles were included in this study.
Results:
Our review showed that cardiometabolic syndrome was associated with increased risk for colorectal, hepatic, endometrial, breast, and bladder cancers. These associations showed variations for sex and geographical locations. For example, the associations were stronger for pancreatic and rectal cancers among women. The strength of these associations was also stronger for sex specific cancers such as breast and endometrial cancers. Studies on European populations showed that these associations were stronger for colorectal cancer among women. However, one study showed that presence of cardiometabolic syndrome contributed protective effects to prostate cancer among American men. In general, strongest associations were found for colorectal cancer among both men and women and hepatic cancer among men. Among cardiometabolic factors, impaired glucose tolerance and central adiposity were the greatest contributors towards increased risk for cancers.
Conclusion:
Given these results, there should be greater focus on primary prevention to identify and treat cardiometabolic risk factors. In addition, patients with greater cardiometabolic risk factors should be screened earlier and more frequently for cancers. A number of gender and geographical gaps identified in this review could be targeted for improvements as per the goals of 2030 sustainable development initiatives. Future studies should consider cardiometabolic syndrome and cancer together and develop effective interventions for decreasing the incidence and morbidity associated with both the conditions.
Metabolic syndrome and its single traits as risk factors for diabetes in people with impaired glucose tolerance: the STOP-NIDDM trial