Discovery

Bariatric surgery, a proven technique for reducing weight in obese patients, has brought remarkable improvement in other aspects of patients’ health. Amazingly, and for reasons not yet fully understood by physician-scientists, type 2 diabetes and other chronic health conditions actually go into remission for many patients after a stomachresizing procedure.

While bariatric surgery has been around since the late 1950s, relatively recent advances, including a minimally invasive approach, as well as studies that show dramatic reversals in chronic health conditions position bariatric surgery as a potent preventive health strategy.

“Obesity has long been recognized as a major contributing factor to a number of disease states,” says Bradley Needleman, MD, a bariatric surgeon who is medical director of the Bariatric Surgery Program at The Ohio State University Medical Center (OSUMC) and one of the first surgeons in the United States to perform the LAP-band procedure, one of the two options offered at OSUMC.

“The prevalence of health challenges among obese adults is well-documented,” he says, noting that hypertension in obese adults stands at 41.9 percent for men and 37.8 percent for women; high cholesterol is evident in 22 percent and 27 percent of obese men and women, respectively; and excess weight and obesity account for 14 percent of all cancer deaths among men and 20 percent among women. “Life expectancy for even amoderately obese individual may be shortened by two to five years,” adds Needleman.

Questions Abound
Needleman explains that, although there are theories about why bariatric surgery is so effective in reversing type 2 diabetes, there is no clear-cut answer yet.

His colleague, Dara Schuster, MD, an endocrinologist who is associate director of the OSUMC Clinical Research Center, is among a group of physician-scientists seeking to unravel the mystery.

“Fat cells, once thought of as inactive sites for the storage of energy, are now known to secrete a variety of substances – including hormones – that have significant effects on the body’s metabolism,” she says.

“There are a couple of hypotheses about the etiology of how gastric bypass reverses type 2 diabetes. One is that by simply losing weight, insulin resistance is reduced and blood sugars are subsequently lowered,” she explains. Another is that blood sugar improves because patients are ingesting smaller volumes of food.

“Although the effect of reversal of type 2 diabetes is seen in both the bypass and the LAP-band procedures, Dean Mikami and I are developing a study to investigate what I think is the most interesting hypothesis,” she adds. Schuster, along with Needleman and Mikami, plan to study how gastric bypass changes the hormonal milieu of incretins – hormones made by the bowel that help modulate pancreatic function. “We think that the bypass actually changes gut hormones that regulate insulin and glucagon secretion, which improves blood sugars.”

In addition, Schuster, who also is associate professor of Internal Medicine and of Pediatrics, and Needleman and Mikami are also collaborating on a study examining adiponectin, a hormone secreted by fat cells, to learn how its ability to impact satiety is changed by bariatric surgery and subsequent weight loss, and how the effect differs by gender. In addition, they are interested in racial differences in hormonal response, as African-American women not only have a higher rate of diabetes but also are less likely to lose weight at the same caloric intake as Caucasian women.

Taking Action
Unfortunately, with weight loss achieved through diet and exercise, as well as through medically supervised liquid diets, there is an unacceptably high incidence of weight regain after two years. Consequently, in just 12 years (1993 to 2005), the volume of bariatric surgery in this country grew more than tenfold, from 16,800 to 178,000 cases annually. Since the 1980s, OSUMC has performed more than 3,000 bariatric surgeries, with Needleman performing more than 1,400 since he became medical director in 2000. Mikami, who joined the program in 2004, has performed almost 500 surgeries.

The OSUMC Bariatric Surgery Program mostly performs two types of stomach-altering surgery: Roux-en-Y (gastric bypass) and the LAP-band procedure. Both are usually performed minimally invasively (laparoscopically), requiring tiny incisions that heal quickly.

In the gastric bypass procedure, the stomach is re-sized to a volume of approximately 30 cubic centimeters, about the size of an egg. The new pouch empties contents directly into the small bowel, “bypassing” the stomach and first part of the small bowel. Patients who undergo this procedure have a recovery time of two to six weeks and experience appetite changes, prolonged feelings of fullness and lose between 50 and 80 percent of excess weight. The main drawback is “dumping syndrome,” which occurs when patients eat foods with high-sugar content. When such foods reach the small intestine, they cause diarrhea, cold sweats, vomiting and lightheadedness, all of which discourage patients from ingesting high-sugar foods. Although there is minimal malabsorption of necessary fats and proteins, patients must have their blood levels monitored on a regular basis.

The LAP-band procedure, which requires about a 10-day recovery, involves wrapping an inflatable band near the base of the esophagus to create a pouch that holds a volume of approximately 10 cubic centimeters. LAP-band differs from bypass in that it is reversible and does not involve dumping syndrome. However, weight loss occurs more slowly and patients generally lose between 20 to 55 percent of excess body weight. Although patients do not need to have blood levels monitored, they may need to have the circumference of the LAP-band adjusted. This does not involve additional surgery, as the band is connected to an inflation port that is placed under the skin during the original surgery.

Personalized Approach
“The National Institutes of Health sets the guidelines for bariatric surgery candidates,” says Lori Lycans, programdirector. In general, patients who have more than 100 pounds to lose are candidates, but specifically, patients between the ages of 18-70 who have a body mass index (BMI) between 35-40 and at least one high-risk co-morbid condition (such as high blood pressure, diabetes or sleep apnea) as well as those whose BMI is greater than 40 who have failed conventional treatment are candidates as well.

She notes that, according to the NIH, those who are morbidly obese (BMI greater than 40) are at higher risk for cancer, diabetes and heart disease. Medicare and most private health insurance companies cover the cost of the procedures for those who meet the guidelines.

Ohio State’s program offers a comprehensive approach. A team of surgeons, endocrinologists, nurse practitioners, nurses, dietitians, psychologists and exercise physiologists work together to evaluate patients. Each patient’s evaluation is based on BMI, medical history, diet and exercise history, psychological state and motivation for surgical intervention. The team also provides minimally invasive surgery, preoperative and postoperative education and care to maximize the benefits of surgery.

“Every patient is a unique individual for whom we help determine the best approach,” explains Kathy Foreman, RN, a nurse practitioner who manages patient intake, evaluations, and education, both before and after surgery. “Prior to surgery, we help patients understand the need for changes in their lifestyle, and we talk with them about the importance of developing an exercise routine they can stick with. We also discuss stress and emotional eating, offering strategies to counteract that, and we go over what to expect after surgery, including possible changes in body image and relationships.”

Patients are encouraged to attend twice-monthly support groups, where they can share their experiences and feelings with other patients, as well as with a behavioral physiologist and dietitian. Most OSU Medical Center Bariatric Surgery Program services are in a single location at the OSU Center for Wellness and Prevention at the Martha Morehouse Medical Plaza on Kenny Road in Columbus.  Learn more about our Bariatric Surgery Program

from left: Dara Schuster, MD; Dean Mikami, MD; Lori Lycans Kathy Foreman, RN; Bradley Needleman, MD