Newswise — If you and a family member have gastric bypass together, chances are you’ll both do much better than if you have surgery alone, according to a new study presented today at the 27th Annual Meeting of the American Society for Metabolic & Bariatric Surgery (ASMBS).

Researchers followed 91 patients from 41 families who were either siblings, parent and child, spouses, cousins, grandmother and granddaughter, in-laws or aunt or uncle and nephew or niece and compared them to a control group of individual gastric bypass patients of similar body mass index (BMI), age and gender.

After six months, one year and two years, family members who had gastric bypass surgery together lost more of their excess weight than patients who had the surgery by themselves. The biggest difference was after one year, where family members lost, on average, about 30 percent more of their excess weight (77% vs. 60%) relative to the control group. The difference was even greater for siblings who lost about 40 percent more of their excess weight relative to the controls (86% vs. 60%).

Obesity-related diseases also resolved or improved at a much higher rate for family members. About twice as many experienced resolution of Type 2 diabetes (65% vs. 31%) and hypertension (60% vs. 33%) after one year. Resolution of sleep apnea was 70 percent and resolution of GERD was 63 percent, compared to 23 percent and 41 percent resolution, respectively, for the control group.

“Clearly the family dynamic, even a little sibling rivalry, can play an important role in patient success,” said Gus J. Slotman, MD, clinical professor of surgery at UMDNJ-Robert Wood Johnson Medical School and the author of the study who performed all the surgeries at Our Lady of Lourdes Medical Center in New Jersey. “Family members are a built-in support system that can help turn a good result into a great result, particularly the first year after surgery when adjusting to a new lifestyle and dietary requirements can be challenging.”

Six months after surgery, the family group had lost 13 percent more excess weight loss relative to the control group (55% vs. 48.5%), a difference that grew to 30 percent at one year (77% vs. 60%). After two years the gap narrowed, though the family group had still lost about 10 percent more excess weight (74.5% vs. 69.5%).

Dr. Slotman says one explanation as to why family members had better overall results is that they were much better at keeping appointments with their doctor following surgery, particularly after the first year. The first six months after surgery 89 percent of patients in the family group and 81 percent of the control group kept their appointments. But at the one year mark, only 58 percent of the control group was keeping their appointments compared to 83.5 percent in the family group. Dr. Slotman suggests that the greater adherence to follow-up care may have helped family members achieve better compliance with post-surgery dietary requirements and may account for the differences in weight loss and disease resolution. Complication rates were comparably low among both groups.

The study found several differences among family member pairings. Adult children lost significantly more weight than their parents, which Dr. Slotman suggested could be because the older a patient is and the longer he or she has been obese, the more difficult it may be to change longstanding eating and exercise habits. Younger patients may also be more motivated to comply with lifestyle changes due to their age and social interactions with peers.

People who are morbidly obese are generally 100 or more pounds overweight, have a BMI of 40 or more, or a BMI of 35 or more with an obesity-related disease, such as Type 2 diabetes, heart disease or sleep apnea. According to the ASMBS, more than 15 million Americans are considered morbidly obese and in 2009 an estimated 220,000 people had some form of bariatric surgery. The most common methods of bariatric surgery are laparoscopic gastric bypass and laparoscopic adjustable gastric banding.

About the ASMBSThe ASMBS is the largest organization for bariatric surgeons in the world. It is a non-profit organization that works to advance the art and science of bariatric surgery and is committed to educating medical professionals and the lay public about bariatric surgery as an option for the treatment of morbid obesity, as well as the associated risks and benefits. It encourages its members to investigate and discover new advances in bariatric surgery, while maintaining a steady exchange of experiences and ideas that may lead to improved surgical outcomes for morbidly obese patients. For more information about the ASMBS, visit www.asmbs.org.