December 5, 2013
S Zhong et al, 2013, Coffee consumption and risk of prostate cancer: an up-to-date meta-analysis, European Journal of Clinical Nutrition, published online ahead of print.
Background/Objectives: Epidemiologic findings concerning the association between coffee consumption and prostate cancer risk yielded mixed results. We aimed to investigate the association by performing a meta-analysis of all available studies.
Subjects/Methods: We searched PubMed, Web of Science and EMBASE for studies published up to July 2013. We calculated the summary relative risk (RR) and 95% confidence intervals (CIs) for ever, moderate and highest consumption of coffee vs non/lowest consumption. The dose-response relationship was assessed by restricted cubic spline model and multivariate random-effect meta-regression.
Results: A total of 12 case-control studies and 12 cohort studies with 42 179 cases were selected for final meta-analysis. No significant associations were found among overall analysis. A borderline positive association was found for highest drinkers in five small hospital-based case-control (HCC) studies involving 2278 cases. However, compared with non/lowest drinkers, the summary RRs were 0.92 (95% CI=0.85-0.99) for ever drinkers, 0.92 (95% CI=0.85-1.00) for moderate drinkers and 0.83 (95% CI=0.72-0.96) for highest drinkers from 12 cohort studies, comprising a total of 34 424 cases. An increase in coffee intake of two cups/day was associated with a 7% decreased risk of prostate cancer according to cohort studies. A significant inverse relationship was also found for fatal prostate cancers and high-grade prostate cancers.
Conclusions: Case-control studies especially HCC ones might be prone to selection bias and recall bias that might have contributed to the conflicting results. Therefore, the present meta-analysis suggests a borderline significant inverse association between coffee consumption and prostate cancer risk based on cohort studies.
Ja tak, jeg vil gerne modtage nyhedsbrev, når der er noget nyt om kaffe og helbred.