By Randy Dotinga
HealthDay Reporter

MONDAY, June 18 (HealthDay News) -- The risk of alcohol problems goes up somewhat in patients who have undergone weight-loss surgery, but not until more than a year after undergoing the procedure, new research finds.

The study doesn't prove that the procedures directly boost the risk of alcohol problems, and it's not clear why the likelihood goes up in the second year after surgery instead of the first. However, previous research suggests that weight-loss surgery may disrupt how the bodies of patients absorb alcohol, giving more of a punch to individual drinks.

One weight-loss surgery specialist questioned the value of the study. But lead author Wendy King, a University of Pittsburgh assistant professor of epidemiology, said the findings "really point to the need for discussions of the benefits and risks to include this."

Weight-loss surgery, also known as bariatric surgery, aims to treat severe obesity by physically limiting the amount of food that the body can process. Several types of bariatric procedures allow physicians to accomplish this by shrinking the size of the stomach.

King said there have been reports in the media about patients who became alcoholics after the surgery, but research is lacking. So King and colleagues followed 2,458 patients -- with an average age of 47 years, 79 percent were female and 87 percent were white -- before and after they underwent weight-loss surgeries. The patients had the procedures between 2006 and 2011.

A year after surgery, the percentage of patients who showed signs of alcohol problems stayed steady at about 7 percent. But two years after the surgery, almost 10 percent showed signs of alcohol problems.

Still, "it's certainly not a surgery that going to make everyone become an alcoholic," King said. "That's not the case."

Alcohol problems were more common in younger patients, males and those who smoked, drank at least a couple of drinks a week or used drugs. Those who underwent a procedure known as Roux-en-Y gastric bypass were also more likely to develop alcohol problems, confirming the results of a Swedish study presented at the Digestive Disease Week conference in 2011.

That procedure, which restricts food intake by creating a small pouch out of the stomach, allows alcohol to be absorbed more quickly by the body, King explained.

Why might weight-loss surgery lead to higher rates of alcohol problems? King said there are several theories. Perhaps, she said, patients become tired of strict rules about what they eat and drink. Or maybe they develop new social lives that include drinking after losing large amounts of weight.

Dr. Edward Phillips, chief of general surgery at Cedars-Sinai Medical Center in Los Angeles, pointed to another potential factor: Extremely obese people -- for example, a 450-pound man -- will lose some of their tolerance for alcohol consumption when they lose weight. "Some just don't realize that less alcohol produces as much or more of an effect," he said.

Despite the findings, weight-loss operations remain the best surgery for severely obese people, King said.

Dr. T. Karl Byrne, a professor of surgery and director of bariatric surgery at the Medical University of South Carolina, was unimpressed by the study, saying it's "not particularly useful."

"The rise in alcoholism after bariatric surgery doesn't seem that significant," he said. "Patients who are morbidly obese are addicted to food. If this addiction is altered or improved with bariatric surgery, there may be transfer of the addiction to alcohol, gambling, hypersexuality, spending and shopping, etc. It's not the surgery. It's the addictive personality."

Phillips, however, found the study useful and said it shows the importance of following up with patients over time, even years after a procedure. "Most patients don't come back if they are OK, or are embarrassed that they are regaining weight, or are using drugs or alcohol," he said.

The study was published online June 18 in the Journal of the American Medical Association.

While the study found an association between weight-loss surgery and increased drinking, it did not prove a cause-and-effect relationship.

More information

For more about weight-loss surgery, try the U.S. National Library of Medicine.

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