Surgery Useful for Morbid Obesity, but Safety and Efficacy Questions LingerSurgery Useful for Morbid Obesity, but Safety and Efficacy Questions Linger

Any debate over the value of bariatric surgery for the treatment of morbid obesity appears over; it works better than lifestyle modification or drug therapy. Whether it becomes the standard of care for patients with morbid obesity remains a question as some insurers refuse to cover the procedure and patients, embarrassed by their condition and burdened by a societal bias that obesity is a personal failure rather than a medical problem, are reluctant to seek treatment.

Advocates like Philip R. Schauer, MD, president of the American Society for Bariatric Surgery, say that surgical weight-reduction procedures are the only proven method of eliminating pounds and keeping them off for the approximately 15 million US individuals with morbid obesity (defined as a body mass index [BMI] >40 or >35 with a comorbid condition such as hypertension or type 2 diabetes).

“For the past few years, important research has been published documenting the tremendous benefit of weight loss surgery,” said Schauer, who is also director of the Bariatric and Metabolic Institute at the Cleveland Clinic. “For the severely obese patient, there is no other therapy that's effective—that's the bottom line.”

Schauer noted that beyond weight reduction, bariatric surgery helps resolve comorbid conditions such as type 2 diabetes, hypertension, hyperlipidemia, and sleep apnea.

Joining in with somewhat more cautious enthusiasm for bariatric surgery is Thomas Wadden, PhD, director of the Center for Weight and Eating Disorders at the University of Pennsylvania School of Medicine in Philadelphia.

“Gastric bypass is by far and above the most effective treatment we have for severe obesity,” Wadden said. “It reduces by 25% to 30% initial body weight, whereas lifestyle modification or drug therapy reduces body weight by just 5% to 10%.”

Preliminary findings announced at this year's annual meeting of the American Society of Bariatric Surgery continued to support use of the procedures. Researchers from the Hospital of Saint Raphael in New Haven, Conn, reported that mortality among patients with morbid obesity who deferred surgical intervention was greater than 10 times the expected rate. In another study, researchers from McGill University, Montreal, Quebec, found that bariatric surgery improved or prevented most cardiovascular-related comorbidities. And researchers from the University of Genoa School of Medicine in Italy concluded that bariatric surgery was safe and effective in adolescent patients.

But while the results were positive, the limitations of the studies presented underlined the need for more rigorous research. In the New Haven study, which focused on 77 patients who met guidelines for surgical intervention but had not undergone bariatric surgery, researchers used telephone interviews to gather mortality data on this group; they then compared the annual death rates within various age ranges for this group with the annual death rates in the general population for persons in the corresponding age ranges. The Canadian study was an observational study with a treatment group of 1035 patients and a control group of 5746 patients. The Italian study looked at 68 patients who underwent bilopancreatic diversion before their 18th birthday between May 1976 and December 2005.

Wadden warned that questions still remain regarding efficacy and safety of bariatric surgery. Indeed, in an article published in July, researchers from the Agency for Healthcare Research and Quality said that almost 40% of patients who undergo bariatric surgery for weight loss develop complications within 6 months of the procedure (Encinosa WE et al. Med Care. 2006;44:706-712). The findings are based on examination of insurance claims for 2522 bariatric surgeries at 308 hospitals. The most common complications were dumping syndrome, which includes vomiting, reflux, and diarrhea; anastomosis complications such as leaks or strictures; abdominal hernias; infections; and pneumonia. The overall death rate was 0.2%. Medical care spending for patients with complications over the 180-day period averaged $65 031 for those who needed rehospitalization and $27 125 for those who did not have to be hospitalized again.

Schauer said the findings were not surprising. “If you break the study down, about half the complications were labeled as nausea, vomiting, diarrhea. I wouldn't call those complications,” he said. “Those are common side effects that are limited and usually resolve during the first 4 months following surgery.” He also noted that the research time frame of 2001 to 2002 preceded the adoption of laparoscopic Roux-en-Y gastric bypass. “A big chunk of their complications were related to the nearly obsolete surgery through big incisions,” he said, adding that current complication rates are much lower and should continue to improve as surgeons perfect their laparoscopic technique.

Wadden is not as quick to dismiss warnings of safety surrounding bariatric surgery, citing a 2005 study (Flum DR et al. JAMA. 2005;294:1903-1908) suggesting mortality rates of 2.8% at 90 days and 4.6% at 1 year. He said these higher rates, including 11.1% at 1 year for patients aged 65 years or older, contrasted with the 0.5% claimed by surgeons practicing in “centers of excellence,” may show what is happening outside leading-edge facilities such as university hospitals.

“The questions surrounding bariatric surgery that are still outstanding focus on safety data,” Wadden said. “The way I read the data [from the JAMA article] is that if you go into a community hospital, you do have greater complication rates. Bariatric surgeons will argue you need to do them in centers of excellence with high volume, but even then we need to study very carefully patients over age 65.”

Such information is important to know as bariatric surgery continues to gain favor. According to the Agency for Healthcare Research and Quality, 13 386 bariatric surgeries were performed in 1998 but that number grew to 71 733 in 2002 (Encinosa WE et al. Health Affairs. 2005;24:1039-1046). And some estimate that up to 200 000 procedures will be performed this year—a number that bariatric surgeons argue is less than 1% of the eligible population.

What is limiting even further growth is the refusal by some insurance companies to pay for the procedure, which can cost up to $25 000, and the lingering public stigma attached to obesity, said Bruce Schirmer, MD, a professor of surgery at the University of Virginia Health System in Charlottesville.

“You can't take an operation that treated cancer effectively and not cover it,” Schirmer said. “You don't see insurance companies saying they won't pay for a lung operation because the patient smokes. Yet the inherent societal biases and public opinion about obesity have allowed them” to not cover bariatric surgery.

Still, the hesitancy of insurers may be coming to an end, as the US Department of Health and Human Services in 2004 eliminated its Medicare policy statement saying that obesity was not a disease. That action helped prompt Medicare to announce earlier this year that it would pay for bariatric surgery, provided it is performed in a designated center of excellence and that data derived from such operations are kept for use by researchers.

Other issues with bariatric surgery are provoking debate.

The procedure is gaining acceptance as a treatment option for teens—patients facing decades of post-op lifestyle modification. This concerns Wadden, who noted that long-term follow-up research remains lacking and the only hard data on mortality reduction—gained from the Swedish Obesity Subjects study of adults only (Sjöström L et al. N Engl J Med. 2004;351:2683-2693)—showed no benefit.

Then there is the movement to provide bariatric options for patients with BMIs under 35, although the research remains preliminary. Researchers from Australia, in a randomized controlled trial of 80 adults with moderate obesity (BMIs of 30-35), concluded bariatric surgery using laparoscopic adjustable gastric banding was more effective than nonsurgical therapy in reducing weight, resolving elements of the metabolic syndrome, and improving quality of life over a 24-month period (O’Brien PE et al. Ann Intern Med. 2006;144:625-633).

Here Wadden draws the line: “Do we move the bar down to [a BMI of] 30? I say, ‘Not so fast.’ In fact, medical therapies and lifestyle changes can be beneficial with patients in this weight range.”

And while bariatric surgery may be the most effective approach to weight reduction for patients with morbid obesity, Wadden said he hoped medicine and society would develop strategies to prevent the condition from occurring in the first place.

“Clearly I support surgery,” Wadden said. “But I hate the thought that this will be the solution to the obesity epidemic, where everyone is getting $25 000 surgeries. We could use that money for interventions that are good for public health, like making sure children have better lunches or communities install sidewalks so people can exercise.”

Expressing another concern is David R. Flum, MD, PhD, Director of the Surgical Outcomes Research Center at the University of Washington in Seattle. Flum worries that no one is thinking about how to triage these potential millions of patients. He notes that while the average BMI of patients having surgery nationwide is in the low 40s, the patients at highest risk of dying from obesity have BMIs in the 50s and 60s.

“Unfortunately, those at highest risk of dying and most disabled from obesity may be those at highest risk for complications and death after the operation,” said Flum, who is also a contributing editor with JAMA . “They may also have the worst insurance as they are often unemployed or disabled.”

Flum said the percentage of poor patients having the surgery has dropped while the total number of procedures has grown nationwide (Santry HP et al. JAMA. 2005;294:1909-1917).

“The question should be, ‘Who should be operated on first?’ and that should not be a matter of who surgeons ‘want’ to operate on the most—those who are low risk and have good insurance,” Flum said. “I think this is an important issue that the medical community has got to deal with to make sure this expensive and effective treatment is applied rationally.”