Alcohol intake and risk of nonmelanoma skin cancer: a systematic review and dose–response meta‐analysis

Abstract

Nonmelanoma skin cancer (NMSC) comprises mainly basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC). The association between alcohol intake and NMSC has been inconclusive; therefore the objective of this study is to quantify the relationship between alcohol intake and NMSC using meta-analyses. A systematic literature search of PubMed and Embase was performed on 30 October 2016. Eligible articles were case-control or cohort studies that examined alcohol intake and risk of BCC or cSCC and reported relative risks (RRs) with 95% confidence intervals (CIs). Of the 307 articles identified, 13 case-control and cohort studies were included in the systematic review, including 95 241 NMSC cases (91 942 BCC and 3299 cSCC cases). A random-effects model was used to obtain summary RRs and 95% CIs for dose-response meta-analyses. For every 10-gram increase in ethanol intake per day, a positive association was found for both BCC (summary RR of 1·07; 95% CI 1·04-1·09) and cSCC (summary RR of 1·11; 95% CI 1·06-1·16). While there was evidence suggesting a nonlinear association for BCC, it may be due to the sparse data at higher alcohol intake levels. This meta-analysis found evidence that alcohol drinking is positively associated with both BCC and cSCC risk in a dose-dependent manner. These results should be interpreted with caution due to potential residual confounding. Nonetheless, because alcohol drinking is a prevalent and modifiable behaviour, it could serve as an important public health target to reduce the global health burden of NMSC.

Evidence for an association between alcohol intake and an increased risk of nonmelanoma skin cancer

“…The results of Yen and colleagues are consistent with those published in a meta‐analysis investigating the relationship between alcohol drinking and melanoma risk . However, current evidence is insufficient to conclude for a causal association between alcohol intake and skin cancer, both melanoma and NMSC, as residual confounding by UVR and other unknown factors cannot be completely ruled out .…”

“…For each alcoholic drink per day, the risk of BCC increased by 7%, and that of SCC by 11%. The risk did not significantly differ by sex for both BCC and SCC, and a positive association was observed only in cohort studies, and for studies located in the U.S.A …”

“…In this issue of the BJD , Yen and colleagues report the results of a systematic review and meta‐analysis to quantify the relationship between alcohol intake and NMSC risk. After an accurate review process, the authors included in their meta‐analysis a total of eight case–control (seven BCC and one both BCC and SCC) and five cohort (two BCC, one SCC and two both BCC and SCC) studies, leading to a total of over 90 000 BCC and 3000 SCC cases.…”

“…In fact, excessive alcohol drinking during outdoor leisure activities can lead to risky behaviours such as excessive sun exposure and infrequent sunscreen use, which in turn lead to sunburn, an established risk factor for skin cancer. Notably, meta‐analytic results showed that a positive association between alcohol intake and NMSC risk was more frequently observed among studies adjusting for UVR exposure‐related factors …”

Healthy lifestyle and life expectancy free of cancer, cardiovascular disease, and type 2 diabetes: prospective cohort study

“…We observed a relatively small difference in life expectancies across different levels of alcohol consumption compared with other individual lifestyle factors. The cardiovascular benefits of moderate alcohol consumption have been consistently observed in large cohort studies,40 but alcohol consumption and risk of cancer showed a dose-response relation 4142. Thus, current guidelines do not encourage a non-alcohol drinker to start drinking just for the benefit of preventing cardiovascular disease.…”