However, disordered eating behaviors, such as binge eating or night eating, lingered for 51% of the 80 women who completed the entire study, says study author Maaike Kruseman, MPH, RD, professor of nutrition and dietetics at the University of Applied Sciences Western Switzerland, Geneva.
The weight loss results, however, were a pleasant finding for researchers and patients, Kruseman says. ''In our center, most patients have a long history of failed diets, so successful weight loss lasting longer than a couple of years was an incredibly good result," Kruseman tells WebMD in an email interview.
Disordered eating after the bariatric or weight loss surgery is not usually documented on a routine basis, she says, but she suspects it is common. "The bypass takes care of one aspect of the patient's problems, but if disordered eating is present before the operation, it will not [usually] disappear by itself, or only rarely," she says.
The study appears in the Journal of the American Dietetic Association.
Bariatric Surgery Study
Initially, 141 patients (including 10 men) were enrolled in the study. The average age was 40. At the study start, the average weight was 274 pounds and the average body mass index (BMI) was 46.
Candidates for bariatric surgery have a BMI of 40 or above, according to the American Society for Metabolic & Bariatric Surgery, or a BMI of 35 or more with an obesity-related disease, such as type 2 diabetes or heart disease. A BMI of under 25 is deemed healthy.
All participants had the type of bariatric surgery known as the Roux-en-Y gastric bypass between 1997 and 2002. In the procedure, the gastric bypass is achieved by reducing the size of the stomach so that a small gastric pouch is created. The small pouch size leads to reduced food intake.
At the 8-year mark, 80 participants, all women, were still taking part in the study. Of those, 47, or 59%, had achieved an excess weight loss of 50% or more, considered successful.
At the end of the follow-up, researchers also found:
- Fifty-three patients or 67% had a BMI under 40; 16 or 20% had shifted from the obesity category to overweight. One woman achieved a normal BMI, under 25.
- The average daily calorie intake went from 2,355 at the study start to 1,680 for the 80 participants who finished the study.
- Younger women were more likely to maintain the successful weight loss.
Eating Problems Continue in Half of Patients
Despite the overall success, Kruseman found that 41 women or 51% had binge eating or night eating syndrome. This points to the need for continued follow-up, she says, with attention given to eating behaviors.
''To my patients who ponder the operation, I ask them to think about their expectations," she says. "It is a very invasive intervention and it has apparently good results, but only on weight. There is no guarantee that their whole life will improve after the operation."
Follow-up Care Important
The weight loss results of the new study are in line with other studies, says John Baker, MD, president of the American Society for Metabolic & Bariatric Surgery and director of the medical weight loss program at Baptist Health in Little Rock, Ark., who reviewed the study for WebMD.
"It's not surprising, the fact that patients still had eating disorder issues," he says. "The surgery doesn't correct those things."
"This [study] is emphasizing the importance of aftercare and allowing the patients access to aftercare," he tells WebMD. That care should include dietary instructions and psychological help to deal with any eating issues, he says.
Another expert says the study results confirm the idea that bariatric surgery requires a long-term commitment by the patient and health care providers. ''The consequences of bariatric surgery can change as patients move through active weight loss to some weight gain," says Trina Histon, PHD, director of the Weight Management Initiative at Kaiser Permanente in Oakland, Calif.
''Patients need various check-ins over the years to ensure they are maintaining optimal care," she says. That way, health care providers can pick up on early warning signs of issues that warrant attention, she says.