OBJECTIVE: It remains unclear whether coffee drinking is associated with colorectal cancer risk. We performed a systematic review and meta-analysis of epidemiologic studies on this issue among the Japanese population.
METHODS: Original data were obtained from MEDLINE searches using PubMed or from searches of the ‘Ichushi’ database, complemented with manual searches. Meta-analysis was performed by using the random effects model to estimate the summary relative risk with 95% confidence interval according to the study design. The final judgment was made based on a consensus of the research group members with consideration for both epidemiological evidence and biological plausibility.
RESULTS: We identified five cohort studies and nine case-control studies. Of these, one cohort study reported a strong inverse association (in women only), whereas three case-control studies reported a strong inverse association with colon or rectal cancer. In meta-analysis, high consumption of coffee was not appreciably associated with colorectal cancer risk among cohort studies, whereas it was associated with significantly lower risk of colorectal or colon cancer among case-control studies. The summary relative risk/odds ratio (95% confidence interval) for the highest versus lowest categories of coffee consumption was 0.95 (0.77-1.17) and 0.78 (0.65-0.95) for cohort and case-control studies, respectively.
CONCLUSIONS: The evidence is insufficient to support that coffee drinking increases or decreases the risk of colorectal cancer among the Japanese population.
The post S Akter et al, 2016. Coffee Drinking and Colorectal Cancer Risk: An Evaluation Based on Systematic Review and Meta-Analysis among the Japanese Population. Japanese Journal of Clinical Oncology, published online ahead of print. appeared first on Coffee and Health.