Mediterranean Alcohol-Drinking Pattern and Alcohol-Related Cancer Incidence in the "Seguimiento Universidad de Navarra" (SUN) Cohort.

Background/

Objectives

Since 1988, the IARC has classified alcohol as a type 1 carcinogen, causally linked to seven types of cancer (oral cavity, pharynx, larynx, esophagus, colorectum, liver and breast carcinomas). Several agencies, such as the WHO and the IARC, hold that there is a direct monotonic association between any gram of alcohol consumed and the risk of cancer, regardless of the drinking pattern. On the other hand, an expanding body of evidence indicates that drinking pattern may substantially modify the effect of alcohol consumption. The Mediterranean alcohol-drinking pattern (MADP) includes different aspects of alcohol consumption, such as preference for red wine, moderate alcohol consumption with meals, spreading consumption over the week and avoiding binge drinking. Conformity to this pattern has shown inverse associations with all-cause mortality, cardiovascular disease and diabetes. However, its relationship with cancer incidence has not been studied yet. Our objective was to assess how alcohol consumption patterns, with particular emphasis on the MADP, relate to the incidence of the seven alcohol-related cancers. This information is needed to support cancer prevention recommendations that may go beyond the amount of alcohol consumed to also include the drinking pattern.

Methods

We prospectively followed 19,541 participants in the SUN ("Seguimiento Universidad de Navarra") cohort for a median of 13.8 years. We classified participants into four groups, namely, abstainers and three further groups according to their adherence to the MADP score (low, moderate and high).

Results

A substantial reduction in the risk of alcohol-related cancer incidence was observed only in men for high versus low adherence to the MADP, with an adjusted hazard ratio (HR) of 0.44 (95% confidence intervals (CIs) (0.21-0.92)). The category of moderate adherence to the MADP showed a lower risk of cancer incidence with a tendency towards statistical significance (HR = 0.56, 95% CI, 0.30-1.06). For women, no result reached statistical significance.

Conclusions

Based on the available evidence, separate messages by sex should be delivered. In men, the association between alcohol and cancer goes beyond the amount of alcohol consumed, and a Mediterranean drinking pattern may be beneficial even for alcohol-related cancers. Men should, therefore, receive an additional message: among alcohol consumers, greater adherence to the MADP may help lower their risk of developing alcohol-related cancers. No benefit is supported for the MADP against alcohol-related cancers in women.