Does drinking a single serving of alcohol each day reduce the risk of developing cardiovascular disease or diabetes?
Several observational studies suggest that it could. These reports have found that people who drink moderate amounts of alcohol were less likely to develop Type 2 diabetes and coronary artery disease.
But only a randomized clinical trial could determine whether alcohol is responsible for these observed health benefits.
That’s why researchers launched the Moderate Alcohol and Cardiovascular Health trial.
The plan was to enroll 7,800 people ages 50 and up who did not have diabetes. Some of them would be randomly assigned to consume about 15 grams of alcohol per day. The others would be asked to abstain from drinking.
Researchers from Beth Israel Deaconess Medical Center in Boston, along with colleagues in the United States, Nigeria, Denmark and the Netherlands, would then follow these volunteers for about six years to see whether the moderate drinkers developed fewer cases of cardiovascular disease and diabetes compared to their teetotaling counterparts.
The MACH trial began enrolling participants in February, and the National Institute of Alcohol Abuse and Alcoholism, part of the National Institutes of Health, intended to spend $20 million on the study over 10 years.
Instead, the NIH announced Friday it would shut down the study over concerns about the way officials solicited funding for the study from companies that sell alcoholic beverages. These “process irregularities” had “undermined the integrity of the research process,” the agency said in a statement.
Critics have also raised questions about how the study would address health risks associated with moderate drinking, such as cancer. These concerns “cast doubt” on the “ultimate credibility” of the study’s findings, the NIH said.
“The quality of NIH-supported research must always be above reproach," said Dr. Francis Collins, director of the National Institutes of Health. "When any problems are uncovered, however, efforts to correct them must be swift and comprehensive.”
Friday’s decision follows the advice of an NIH advisory committee that was asked to dig into these issues.
The committee recommended that the trial be ended for a variety of reasons, including funding “irregularities,” an apparent attempt to unfairly steer the study to a particular researcher, and “concerns about study design.”
In its investigation, the committee turned up evidence that staff members of the National Institute of Alcohol Abuse and Alcoholism were in frequent contact with outside researchers who hoped to conduct the MACH trial, as well as with companies that might be persuaded to fund the project.
Committee members were particularly concerned that in their attempt to secure industry funding, NIAAA employees were designing the study in a way that would highlight any potential health benefits of moderate drinking while downplaying any potential risks.
“Interactions among several NIAAA staff and industry representatives appear to intentionally bias the framing of the scientific premise in the direction of demonstrating a beneficial health effect of moderate alcohol consumption,” the committee wrote in its report.
As an example, they said that an independent review of the study design determined that it didn’t track enough participants for a long enough period of time to determine whether moderate drinking could increase the risk of cancer. They study also omitted any effort to assess alcohol’s potential role in heart failure.
“Thus, the trial could show benefits while missing harms,” the committee wrote.
By the time the clinical trial launched, companies including Anheuser-Busch InBev, Heineken, Carlsberg Breweries A/S, Diageo (maker of Tanqueray gin and Captain Morgan rum) and Pernod Ricard USA (maker of Absolut Vodka and Chivas Regal Scotch whisky) had agreed to contribute $67.7 million in funding.
The committee report described multiple inappropriate communications among NIAAA senior staff, the researcher who became the trial’s principal investigator, and industry executives being groomed for funding.
For instance, in emails and conference calls, the study leader and NIAAA staffers addressed concerns about the trial design that were raised by alcohol producers. Eventually, they asked that an email to a potential funder be amended to state that “one of the important findings will be showing that moderate drinking is safe.”
Neither the study leader nor the staff members are named in the report, but the website for the MACH trial lists Dr. Kenneth Mukamal of Beth Israel Deaconess Medical Center as the study’s principal investigator.
In other emails, a trade group representing European spirits makers told NIAAA staffers of its interest in a potential agency-sponsored conference that would highlight the health benefits of alcohol.
And in an email among NIAAA employees, one person describes his or her intent to conceal from NIH leaders an editorial in the medical journal BMJ that argued “that reduction of alcohol consumption, even for light to moderate drinkers, is beneficial for cardiovascular health.”
That internal email was addressed to “team health benefits of drinking.”
Given all these such concerns surrounding about the study’s flaws, its ultimate conclusions were unlikely to “be actionable or believable,” the advisory committee wrote.
A separate investigation from the NIH’s Office of Management Assessment found that “a small number of NIAAA employees” did not follow agency policies regarding in their attempts to secure outside funding and to select a principal investigator for the study.
The NIH said it would take “appropriate personnel actions” but added that it could not discuss details about specific employees.
The agency also pledged to share both reports with the inspector general for the Department of Health and Human Services, which oversees the NIH.
Outside funding for NIH-sponsored studies is solicited by the Foundation of the National Institutes of Health, an independent nonprofit organization established by Congress in 1990. The FNIH has “firewalls” to make sure companies don’t influence the studies they support and to prevent other potential conflicts of interest.
The advisory committee found that the FNIH acted appropriately with regard to the MACH study, and in fact was kept “in the dark” by those at NIAAA who had been talking with industry funders for more than two years before FNIH got involved, according to its report.
The NIH Office of Management Assessment agreed that the FNIH “conducted its role appropriately,” the NIH said.
To root out any similar shenanigans elsewhere in the agency, each institute will immediately review its existing procedures and consider “additional measures” to identify conflicts of interest between researchers and potential funders, the NIH said.
It will take a few months to wind down the trial in an orderly manner. As of Friday, $4 million in NIAAA funds and $11.8 million from industry sources had been spent on the study, and 105 participants had been enrolled.