LAUSR

Background The association between environmental and socioeconomic risk factors and the occurrence of hepatocellular carcinoma (HCC) are still inconclusive. A meta-analysis was conducted to address this issue. Methods We systematically searched the databases including PubMed, Web of Science, and Google Scholar and collected the related risk factors of HCC before March 6, 2020. Statistical analysis was performed on the odds ratio (OR) value and 95% CI of the correlation between environmental and socioeconomic factors and HCC. Begg's rank correlation test, Egger's linear regression test, and the funnel plot were employed for identification of the publication bias. Results Out of 42 studies, a total of 57,892 participants were included. Environmental and socioeconomic risk factors including ever educated (illiteracy); race (Black, Hispanic, and Asian); medium and low incomes; occupations (farmer and labor); passive smoking; place of residence (rural); blood aflatoxin B1 (AFB1) adduct level; exposure of pesticide, etc., were statistically increased with the occurrence of HCC (P < 0.05) and OR values and 95% CIs were 1.37 (1.00, 1.89), 2.42 (1.10–5.31), 1.90 (0.87–4.17), 5.36 (0.72–40.14), 1.48 (1.11, 1.96), 1.74 (1.00–3.03), 1.49 (1.06–2.08), 1.52 (1.07–2.18), 1.43 (0.27, 7.51), 1.46 (1.09, 1.96), 2.58 (1.67–3.97), and 1.52 (0.95–2.42), respectively. We found 6–9, 9–12, and ≥12 years of education that statistically reduced the risk of the occurrence of HCC (P < 0.05) and OR values and 95% CIs were 0.70 (0.58, 0.86), 0.52 (0.40, 0.68), and 0.37 (0.23, 0.59), respectively. No significant associations (P > 0.05) were observed between race (Hispanic and Asian), passive smoking, marital status, place of birth, place of residence, and HCC. In stratified analysis, exposure of pesticide was statistically significant (P < 0.05), while race of black was on the contrary. Conclusion Environmental and socioeconomic risk factors have great impacts on the incidence rate of HCC. Improving national education and income levels can significantly reduce the risk of HCC. PROSPERO Registration https://www.crd.york.ac.uk/prospero/, identifier: CRD42020151710.