What used to be accepted as gospel – that moderate drinkers
are healthier than nondrinkers or heavy drinkers – has been challenged in
recent years, and a new
study to be conducted by the National Institutes of Health aims to settle
the question once and for all. The study plans to enroll about 8,000 volunteers
aged 50 or older from around the world, who will be assigned to avoid drinking
or have one drink per day for 6 years. The lack of such large scale prospective
studies is one reason why the question of alcohol’s influence on health and
longevity remains subject to debate. However I am not sure the study will yield
the answers it seeks to, but not for the reasons others are already finding to
criticize the project.
It’s an ambitious
undertaking, with an equally ambitious price tag of US$100 million. The plan is
for most of the money to come from the alcoholic beverage industry through
grants, and $68 million has reportedly already been pledged. Skeptics point out
that many of the study’s investigators have accepted money from alcohol industry
groups in the past, and raise the issue of scientific influence peddling. But
the study’s principal investigator, Dr. Kenneth Mukamal of Harvard, has no such
ties and has authored numerous research articles on alcohol and health. As
someone who has been a clinical investigator myself, I can vouch for the many
levels of independent oversight that prevent any influence by investigators on the
results. There's just no way to slip things through, and no reason to risk one's reputation by attempting to.
The challenges to the long held view that alcohol in
moderation has a net positive benefit come largely from different types of studies,
such as the one I critiqued in last
month’s blog. These studies aggregate previously done observational studies
(as opposed to interventional studies, like the NIH trial). The example I used
last month essentially “cherry picked” the studies that met the criteria that
would yield the desired findings. It's not new research, just old research repackaged to imply a different interpretation - one that fit the goals of an alcoholism treatment center.
But conflicts of interest are not the problem with the NIH
trial, it is the complexities of human behavior. Volunteers willing to give up
drinking will come from a specific subset of individuals that may not be
representative of the average consumer. Allowing people to choose their
beverage or to vary which one they drink could make it difficult to see if wine drinkers, for
example, are different (evidence suggests that wine drinking is not the same as
other types of drinking.) It may be that more than one drink per day is the
optimal dose, and the effect too small to be statistically significant with
only one. Another issue is the pattern of drinking; with wine, it is the
relationship with meals. And how will the one drink per day rule be enforced?
What of people who for whatever reason choose not to have a drink, or make up
for it by skipping a couple of days then having several?
I do applaud the effort required to do this study, but I
expect that whatever the results they will be challenged by those with an
opposing ax to grind.
Comments
Post a Comment