1 Department of Clinical Medicine, Xingtai Medical College, 618 Gangtie Road Xingtai, Hebei 054000, China
2 Department of Occupational & Environmental Health Sciences, School of Public Health, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
3 Faculty of Education, Brock University, 500 Glenridge Avenue, St. Catharines, ON, L2S 3A1, Canada
4 Department of Nutrition & Food Hygiene, School of Public Health, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
5 Department of Clinical Epidemiology & Biostatistics, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4L8, Canada
* Corresponding author Email: email@example.com
Quantities of studies investigating coffee consumption and risk of hepatocellular carcinoma have reported different findings. The aim of this study was to perform a meta-analysis of cohort studies to clarify the effect of coffee intake on risk of hepatocellular carcinoma and to conduct an exhaustive stratified and dose–response analyses.
Materials and Methods
Electronic reference databases including MEDLINE, the Cochrane Controlled Trials Register, EMBASE, and Science Citation Index and PubMed (up to May 2013) were searched to identify eligible cohort studies investigating relationship between coffee consumption and risk of hepatocellular carcinoma. Study-specific relative risk estimates were pooled using a random-effects model.
Ten cohort studies (including 553,088 participants and 1649 hepatocellular carcinoma cases) were included in the meta-analysis. The summary relative risk for coffee drinkers versus non-drinkers was 0.64 (95% confidence interval: 0.55, 0.75), while relative risk for lowest and highest drinkers was 0.75 (95% confidence interval: 0.65, 0.87) and 0.48 (95% confidence interval: 0.39, 0.60), respectively. An increment of one cup of coffee per day was significantly related to decreased risk of hepatocellular carcinoma (relative risk: 0.82, 95% confidence interval: 0.78, 0.87). Subgroup, sensitivity and detailed dose–response analyses indicated the robustness and insensitiveness of the relationship between coffee intake and reduced risk of hepatocellular carcinoma.
Based on the evidence of cohort studies, the meta-analysis confirms that coffee consumption is associated with reduced risk of hepatocellular carcinoma. The inverse relationship between coffee and risk of hepatocellular carcinoma was consistent across different populations and settings.