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.
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."
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."
