Excess Body Weight and the Risk of Liver Cancer: Systematic Review and a Meta-Analysis of Cohort Studies

Abstract

Objective: To update and expand the previous meta-analysis including all prospective studies on the issue of the associations between overweight, obesity, and liver cancer risk. We also performed a meta-regression to investigate a potential nonlinear and/or linear association between body mass index (BMI) and liver cancer risk.

Methods: Literature search was conducted in four libraries from the beginning of indexing for each database to 1st September, 2018.

Results: The summary risk estimate was statistically significant on the association between overweight and the risk of liver cancer incidence (relative ratio [RR] = 1.19). The RRs were significantly stronger in people with known liver disease with overweight than in the general population with overweight (RR = 1.50 vs. RR = 1.10; P_difference = .02). The meta-analysis showed an increase by 87% on the risk of liver cancer incidence in obesity categories, relative to categories of normal BMI (RR = 1.87, P < .01). Moreover, the results showed that, overweight was associated with 9% increased and obesity with 66% increased for risk of liver cancer mortality. In linear model, the relative risks of liver cancer were 1.32 for continuous BMI per 5 kg/m² increase.

Conclusion: This meta-analysis supports the hypothesis that overweight, obesity may significantly increase liver cancer risk.

Additional information

Funding

This work was supported by National Natural Science Fundation of China (NSFC 81872618), the Key Research and Development projects of the Ministry of Science and Technology (No.2016YFD0400604–02), and the Scientific Research Foundation for the Cultivation of Excellent Doctoral Dissertations in Southeast University (YBPY1944). The funders had no role in the study design, data collection, data analysis and interpretation, writing of the report, or the decision to submit the article for publication.