Latest scientific news 25 June 2019

Critical letters from scientists to the Lancet editor

In August 2018, the Global Burden of Disease Study (GBD) was published in the Lancet and made headlines claiming no safe level of alcohol intake exists (*).

Now, 10 months later, the Lancet finally published the critical responses received from a number of renowned scientists who commented on the methodology and the incorrect conclusions drawn.

Among them:

  • Di Castelnuovo A, Costanzo S, de Gaetano G state: …“the most reliable way to reach a definite conclusion is to analyse the association of alcohol with all-cause mortality. We are therefore surprised that the investigators did not consider total mortality as an outcome. …. The way the curves were combined was not validated, contain a dose of arbitrariness and did not take into account the variability in precision because each curve is derived from a different sample size. Thus, the conclusion that no level of alcohol consumption improves health cannot be drawn from the GBD 2016 Alcohol Collaborators study.”
  • Shield K, Rehm J conclude: …“limitations in the methods have led to the unfounded conclusion that, at the individual level, no amount of alcohol consumption benefits health.” When these errors were corrected, the authors find health benefits for individuals who consume 12 g of alcohol per day compared to abstainers.
  • Abat C, Roussel Y, Chaudet H, Raoult D state: …“most of the 23 health outcomes they studied, including stroke, myocardioal infarction and cancer, are diseases associated with ageing. However, the authors attributed them to alcohol rather than longer lifetime. Advising policy makers with such results could represent a political instrumentalisation of the journal’s reputation.”
  • Astrup A, Estruch R write: “There is no question that heavy drinking is harmful to health and contributes to an excess of deaths and disability globally, but these findings do not justify the conclusions that the level of alcohol consumption required to minimise health loss is zero and that efforts should be made to lower overall-population-level alcohol consumption.”

Many more of such critiques by scientists are needed to alert media and public alike when ideologically based study results are communicated. In particular, when the evidence level does not allow to draw conclusions for recommendations. Furthermore, the corrections were published late and won’t undo the damage in public perception by the earlier headlines.

(*) The Global Burden of Disease Study (GBD) was a big study merging data from 694 observational studies with 28 million people in 195 countries. The authors found that pooling 23 alcohol-related health outcomes indicated a 0.5% increase in relative risk for moderate drinkers (1 drink/day) and concluded that the protective effect of alcohol for some health conditions was offset by the risk of others and that there is no safe level of alcohol intake. Based on these results, the authors recommended to revisit worldwide alcohol control policies and health programmes and consider recommendations for abstaining from alcohol.