Re: Alcohol intake in relation to non-fatal and fatal coronary heart disease and stroke: EPIC-CVD case-cohort study
We read with great interest Ricci C. et al.’s paper (1) regarding the relationship between alcohol intake and risk of coronary heart disease (CHD) or stroke. The considerable number of clinical events which were accounted for in their paper, along with the information concerning the subjects’ lifetime consumption of alcohol (rarely collected and presented), are of significant importance.
According to the Authors, the most salient result of their paper seems to be the positive relationship identified between alcohol intake and stroke. However, the risk for fatal stroke was highest among abstainers (HR 1.41 vs. reference group) and numerically greater than for the highest alcohol consumption group (≥60 g/day; HR 1.14 vs. reference group). As for non-fatal stroke, both groups (abstainers and subjects consuming ≥ 60 g of alcohol per day) had comparable risks (HR 1.26 and 1.31, respectively, vs. reference group). One should also note that a statistically significant increase of HR for non-fatal stroke was only observed for non-drinkers and drinkers of >60.0 g/day, while for fatal stroke a higher HR was only significant for non-drinkers.
Based on these non-significant positive correlations identified between stroke risk and alcohol intake, the Authors draw conclusions which may serve, they say, as additional evidence in favour of population strategies for reducing alcohol use. However, these conclusions do not take into adequate consideration the relationship between alcohol intake and CHD risk, which also clearly emerges from their data. Even disregarding the data from abstainers (as was done by the Authors), and assuming that the observed correlations between alcohol consumption and stroke and CHD risk are both causal in nature, any reduction of alcohol consumption would reduce the incidence of cerebrovascular events at the cost of a much greater increase in the incidence of CHD events. Based on their data, indeed, we calculated that if the alcohol intake by those consuming >30g/day had been brought, at the beginning of the observation period, to 0.1-4.9 g/day, 141 strokes (12 fatal and 129 non-fatal) would have been avoided, but 589 additional CHD events (40 fatal and 549 non-fatal) would have been observed.
Besides the fact that the heavy and or irregular alcohol intake must be strongly discouraged, we believe that the complex nature of the relationship between alcohol consumption and overall clinical events (which also extends to all-cause mortality) (2,3) does not presently allow any definitive recommendation to be made, nor does it support the assumption that a zero-alcohol consumption would be the best health option for the general adult population.
1- Ricci C et al, BMJ 2018;361:k934
2- Di Castelnuovo A, Costanzo S, Bagnardi V et al. (2006). Alcohol dosing and total mortality in men and women: an updated meta-analysis of 34 prospective studies. Arch Intern Med, 166(22):2437-2445.
3- Wang C, Xue H, Wang Q et al. (2014). Effect of drinking on all-cause mortality in women compared with men: a meta-analysis. J Womens Health, 23(5):373-381.
Competing interests: AP is Chairman of NFI-Nutrition Foundation of Italy, a no profit organization partly supported by 18 Food and Beverage companies, few of which market alcohol containing beverages. ADC is Co-Principal Investigator of a grant from ERAB /EA 17 67): The European Foundation for Alcohol Research, outside the submitted work. GdG is a member of the International Scientific Forum on Alcohol Research, an independent organization of scientists that prepares critiques of emerging research reports on alcohol and health. The members of the Forum donate their time and effort in the review of papers and receive no financial support. The Forum itself receives no support from any organization or company in the alcoholic beverage industry. GdG is also a consultant to the Web Newsletter of Assobirra, the Italian Association of the Beer and Malt Industries, and a corresponding member of the non-profit Accademia Italiana della Vite e del Vino.