Weight Loss Surgery News

Want to know the latest developments in weight loss surgery? Read on.

New Research Highlights Why Some People Don't
Lose Weight After Gastric Bypass

SAN FRANCISCO, September 2008 — While the secret to success after bariatric surgery may be as simple as following your surgeon's instructions, new research shows that the deck may be stacked against certain individuals from the get-go. This includes those with diabetes and those whose stomach pouches are left on the larger size after gastric bypass surgery. The new report appears in the September issue of Archives of Surgery.

Although Roux-en-Y gastric bypass surgery is often successful, a handful of people do not lose weight successfully even with regular follow-up. The new study sheds light on why.

Of 310 patients with an average body mass index (BMI) of 52 before surgery, 12.3 percent had poor weight loss. Poor weight loss was defined as losing 40 percent or less of excess body weight after 12 months. Good weight loss was defined as losing more than 40 percent of excess weight.

After adjusting for other related factors, diabetes and having a larger size stomach pouch after gastric bypass surgery were independently associated with poor weight loss, the study showed.

People with diabetes may take insulin or other drugs that stimulate the production of fat and cholesterol, the authors wrote. "Other factors that may lead to weight gain in patients with diabetes include a 'protective' increase in caloric intake to treat episodes of hypoglycemia [low blood sugar], reduction of urinary glucose losses and sodium and water retention that are a direct effect of insulin on the distal tubule in the kidney," they explained.

During gastric bypass, the once football-sized stomach becomes the size of a golf ball. Many bariatric surgeons estimate pouch size using anatomical landmarks instead of a more specific sizing balloon. The pouch size plays a significant role in how much a person can consume. "As the use of gastric bypass continues to grow, we believe it is critical to stress the importance of and to teach the creation of the small gastric pouch and to better standardize the technique used for pouch creation," the authors wrote.

This does not mean that individuals are set up to fail. "Changes in the use of diabetes medications may reduce the risk of poor weight loss among diabetics undergoing gastric bypass," the authors suggested. "Detailed attention to the creation of a small gastric pouch is essential for achieving the best results."

The researchers are all affiliated with the University of California, San Francisco. — Denise Mann

Bariatric Surgery Improves Asthma, Autoimmune Disease

WASHINGTON, D.C., June 2008 — Obese people with asthma, osteoarthritis or autoimmune diseases who undergo bariatric surgery may be able to say sayonara to their steroids and/or the other immunosuppressing drugs they use to treat these diseases within about 18 months of their surgery. This is according to new research presented at the 25th annual meeting of the American Society for Metabolic amd Bariatric Surgery.

And that's a good thing, as long-term use of these drugs can have harmful effects on health. Precisely how bariatric surgery can help resolve or improve these diseases is not fully understood, but losing weight may decrease certain inflammatory markers that are known to be elevated in autoimmune and inflammatory disease, according to study author Elizabeth A. Dovec, MD, a bariatric surgeon at Western Pennsylvania Hospital, a teaching hospital of Temple University School of Medicine in Pittsburgh.

The new study comprised 49 morbidly obese people who were taking steroids or other immunosuppressive medications to treat co-existing chronic autoimmune diseases, including rheumatoid arthritis (RA), myasthenia graves (a neuromuscular disease characterized by weakness of the skeletal muscles) and lupus, or inflammatory diseases like asthma. In autoimmune diseases, the body engages in friendly fire against its own organs or systems.

More than 50 percent of the study patients were able to discontinue or significantly reduce the use of oral steroids and immunosuppressive agents within 18 months. Specifically, 89 percent of people with asthma who underwent bariatric surgery were able to discontinue their steroids. What's more, 33 percent of patients with the inflammatory skin disease psoriasis and 25 percent of those with myasthenia graves were able to stop taking their medication.

In addition to improvements in autoimmune and inflammatory disease, the study participants lost 65.2 percent of their excess weight, and 80 percent of the study participants showed improvements or resolution of many of their other obesity-related diseases, including type 2 diabetes, obstructive sleep apnea and high blood pressure.

"Patients with compromised immune systems [such as occur with autoimmune disease] or taking steroids for chronic inflammatory disease [like asthma] may have been excluded from bariatric surgery because they are at higher risk for complications related to their disease or immunosuppressant medications," said another study author, Daniel J, Gagné, MD, director of bariatric surgery and laparoscopic and minimally invasive surgery at the hospital. "However, this study shows not only that these patients can safely have bariatric surgery, but they can achieve significant improvements or elimination of many diseases." — Denise Mann

Losing 20 to 50 Percent of Excess Weight Can Improve
Obesity-Related Health Conditions

WASHINGTON, D.C., June 2008 — Obese individuals who lose less than half of their excess body weight within a year of undergoing gastric banding surgery may see dramatic improvements and/or complete resolutions of certain obesity-related conditions including type 2 diabetes, high blood pressure, high cholesterol and sleep apnea, according to study results released at the 25th annual meeting of the American Society for Metabolic and Bariatric Surgery. Read the complete story.

Cancer Risk Slashed After Bariatric Surgery

WASHINGTON, D.C., June 2008 — Obese individuals who undergo bariatric surgery substantially slash their risk of certain obesity-related cancers, according to a new study presented at the 25th annual meeting of the American Society for Metabolic and Bariatric Surgery in Washington, D.C.

Calling this a "very exciting finding," lead researcher Nicolas Christou, MD, PhD, director of bariatric surgery and professor of surgery at McGill University in Montreal, said that "hopefully subsequent studies will shed more light on [this subject]."

Being overweight or obese raises the risk of several types of cancer including breast, colon, esophageal and kidney, according to the American Cancer Society. Every year 500,000 Americans die of cancer, and one-third of these deaths is linked to diet, lack of physical activity and being overweight, the group states.

Exactly how weight loss surgery reduces cancer risk is not fully understood, Christou says. "A lot of cancer risk is genetic, and we don't alter a person's genetic," he says. "Is it hormonal? We don't know."

Perhaps, he speculates, "it is the inability to eat a 16-ounce porterhouse steak that is barbequed with carcinogens," he says. Many cancer-causing chemicals or carcinogens are created during cooking. Consuming large amounts of red meat has also been linked to certain cancers. Weight loss surgery patients are unable to eat large volumes of food, due to the decreased size of their stomach following surgery.

In the study, bariatric surgery patients were 78 percent less likely to develop any cancer, when compared with their equally overweight counterparts who did not undergo weight loss surgery. Bariatric surgery patients had an 83 percent reduction in their risk for developing breast cancer and a 68 percent reduction in risk of developing colorectal cancer, when compared with their counterparts who did not have surgery.

Reductions were also seen in risk for other, more rare cancers such as pancreatic cancer, endometrial cancer, kidney cancer, myeloma, melanoma and non-Hodgkin's lymphoma among those participants who underwent weight loss surgery; however, these reductions were not statistically significant, Christou said.

The Canadian Bariatric Cohort Study compared 1,035 bariatric surgery patients with 5,746 controls who were matched for body mass index and did not undergo surgery to lose weight. They were tracked for a maximum of five years. None of the study participants had a history of cancer. During the study period, two percent of people in the surgery group were diagnosed with cancer, compared with 8.5 percent of participants who did not have bariatric surgery. — Denise Mann

Psst. Want in on a Secret? Follow-Up is the Secret to Success Following Weight Loss Surgery, Says Survey

WASHINGTON, D.C., June 2008 — In a new survey, those patients who heeded their doctor's advice following surgery lost about 35 percent more weight than those who did not take their doctor's advice as seriously or as literally. What's more, those who listened were more likely to keep the weight off. The survey findings were released at the 25th annual meeting of the American Society for Metabolic and Bariatric Surgery in Washington, D.C. Read the complete story.

Can Weight Loss Surgery Prevent Cancer? Maybe

SAN FRANCISCO, June 2008 — Add heightened immune defense against cancer and infections to the growing list of benefits of bariatric surgery, says new research presented at The Endocrine Society's 90th annual meeting.

Obese individuals are known to be at increased risk for colon, breast, endometrial, kidney and esophageal cancers. The study looked at how weight loss affected the immune functions of 28 morbidly obese patients who had traditional Roux-en-Y gastric bypass surgery. This surgery creates a small stomach pouch to curb food intake by stapling a portion of the stomach. Then, a Y-shaped part of the small intestine is attached to the stomach pouch so that food can bypass the duodenum (the first part of the small intestine located between the stomach and the middle part of the small intestine).

The 20 women and eight men in the study lost an average of 78.5 pounds six months after surgery.

The researchers evaluated patients' blood samples for natural killer (NK) cells, which play a critical role in controlling infections and cancer, both before and six months after the surgery. Specifically, they measured the number of NK cells and the cells' capacity to kill infected cells or tumor cells. They also looked at the production of certain cytokines (inflammatory proteins that are key players in immune response).

Although the number of NK cells did not increase with weight loss, their activity changed. Before surgery, NK cells mounted a weak immune defense, but after surgery their activity increased by nearly 79 percent. The study authors conclude that this represents an improvement in the effective immune response and, possibly, in the ability to fight cancer and infections.

The response of cytokines involved in NK cell activity also changed after weight loss, possibly providing greater protection against infection and cancer, the researchers found. — Denise Mann

Can Weight Loss Surgery Restore Sexual Function in Obese Men? New Research Says Oh Yes

ALBUQUERQUE, N.M., May 2008 — Morbidly obese men who undergo gastric bypass surgery may see improvements in their sex life as a result of the dramatic weight loss, according to new research presented at the 103rd Annual Scientific Meeting of the American Urological Association in Orlando, Fla.

It is no secret that men who are overweight or obese may experience erectile dysfunction and other sexual problems. "This study shows that weight loss and other risk factors which are alleviated by weight loss may be keys to restoring sexual function," said lead researcher Anthony Y. Smith, MD, a urologist at the University of New Mexico Health Sciences Center in Albuquerque, N.M. "These results give men another reason to improve their health by losing weight."

In the new study, 95 obese men filled out a standardized questionnaire regarding their sexual function before and after undergoing gastric bypass surgery. All the men reported improvements in sexual drive, erectile function, ejaculatory function and sexual satisfaction after their weight loss surgery. The more weight they dropped, the better their sex life got, the study showed.

The researchers also compared the men's scores with those of men who participated in the Olmsted County Study of Urinary Health Status Survey. This study is often used as a baseline for comparison. After the men in the new study lost an average of 67 percent of their body weight, their scores were similar to those of men in the comparison study. — Denise Mann

Can Weight Loss Surgery Relieve Low Back Pain?
Preliminary Study Says Yes

CHICAGO, April 2008 — Research has shown that weight loss surgery can improve type 2 diabetes, heart disease, sleep apnea and other known complications of obesity. Now a new study shows that weight loss surgery can also take the bite out of pre-existing back pain. The findings were presented at the 76th annual meeting of the American Association of Neurological Surgeons.

More than one-third of U.S adults were obese in 2005-2006, and as many as 85 percent of all Americans will experience an episode of back pain at some point in their lives. Despite these converging epidemics, little is known about how obesity affects low back pain, also known as lumbar spine degeneration.

In the new study of 38 people with low back pain who underwent gastric bypass surgery, participants not only lost weight, they also showed a 44 percent reduction in the intensity of their back pain in the year following their surgery. What's more, study participants also showed improvements on standardized measures assessing their quality of life and disability following the weight loss surgery.

Specifically, the average weight decreased from 317 pounds to 232 pounds in the year after surgery, and body mass index (BMI) decreased from about 52 to 38, the study showed. A BMI takes height and weight into account to measure body fatness. A BMI of 30 or above in adults is considered obese. [Read more about body mass index, and use our BMI calculator.]

"This study provides evidence that substantial weight reduction following bariatric surgery results in moderate reductions in preexisting back pain within six months of weight loss," the study authors conclude. "While this initial research is promising, larger long-term trials are needed to prove the efficacy of this treatment." — Denise Mann

Normal-Weight Obesity Linked to Heart Risks

ROCHESTER, Minn., April 2008 — Think that having normal weight means you are in a good place health-wise?

Think again.

More than half of normal-weight Americans actually have a high percentage of body fat, which places them at risk for diseases associated with obesity, such as heart disease, diabetes and other metabolic disorders. This is according to a new study by Mayo Clinic researchers.

The study showed that men whose body fat is greater than 20 percent and women whose body fat is greater than 30 percent have "normal-weight obesity," even though their weight may be normal for their size. The researchers defined "normal weight" by body mass index (BMI) and "normal-weight obesity" as a condition of having a normal BMI with high body fat percentage.

The researchers looked at risk factors for heart disease, diabetes and metabolic syndrome (a precursor of diabetes) among 2,127 people who participated in the U.S. government's Third National Health and Nutrition Examination Survey.

Overall, 61 percent of the participants had levels of body fat that indicated "normal-weight obesity." When these participants were compared with their normal-weight counterparts, they had higher cholesterol and triglyceride levels, higher blood sugar levels and higher rates of the metabolic syndrome — all of which increase risk of heart attack and stroke.

The researchers suggest that measuring abdominal obesity or assessing percentage of body fat may be more reliable ways to assess heart risks than tracking just weight and BMI. — Denise Mann

Is There a New Weight Loss Drug on the Block?

CHICAGO, April 2008 — An experimental weight loss drug called taranabant helped dieters shed about 14.5 pounds over one year, says a new study.

The study involved 414 patients who were randomly assigned to take two milligrams of taranabant daily and 417 patients who were given a dummy pill. It took roughly nine months for people taking the new pill to reach their lowest weight, and they were able to maintain this weight for the rest of the year.

Participants who took the new drug also experienced a rise in levels of high density lipoprotein (HDL) or "good" cholesterol and a drop in dangerous blood fats called triglycerides.

The most common side effects were nausea and diarrhea, but less than 2 percent of patients dropped out because of these problems.

The new drug targets the cannabinoid system by inhibiting certain receptors there. This drug is similar to rimobabant, which has been referred to as the "anti-munchies" drug because it blocks the same receptors that smoking marijuana stimulates (resulting in a ravenous appetite called "the munchies").

Rimobabant did not get approval from an FDA advisory panel, mainly because of concern that it could increase risk of depression and/or suicide. People taking taranabant also showed a high rate of psychiatric problems.

Speaking of rimobabant, this weight loss drug got mixed reviews at the American College of Cardiology's annual conference in late March. A study did not find any evidence that it actually slowed the buildup of arterial plaque, but it did decrease one particular measure of plaque build-up in the heart arteries. The trial's main outcome measure was a change in the percent atheroma volume (PAV), and the secondary outcome was a change in normalized total atheroma volume (TAV). PAV and TAV are different measurements of plaque build-up in an artery. The study did not show a decrease in PAV, but it did show a decrease in TAV. These findings also appear in the Journal of the American Medical Association. — Denise Mann

Statins Still Rule for Lowering Cholesterol

CHICAGO, April 2008 — The ever-popular statin drugs are still king when it comes to lowering cholesterol.

A group of researchers analyzed a study looking at a newer cholesterol-lowering pill called Vytorin (ezetimibe and simvastatin), designed to pack a one-two punch against artery-clogging cholesterol by combining a unique cholesterol drug called Zetia with the statin drug Zocor (simvastatin). Statins work by blocking HMG-CoA reductase, an enzyme in the liver that makes cholesterol.

But it turns out that Vytorin was no better than Zocor alone at slowing plaque buildup in the heart arteries of high-risk patients. These results were released at the American College of Cardiology annual meeting and published online by The New England Journal of Medicine. — Denise Mann

Is Obesity in Your Genes?

DANVILLE, Pa., March 2008 — Genetic research may shed light on why some people gain weight back after weight loss surgery.

A combo of two obesity-related genes may be linked with an increased body mass index (BMI) among severely obese patients who are undergoing weight loss surgery, according to a new study reported in the March issue of Archives of Surgery. People with the gene combo may be more likely to pack on pounds after weight loss surgery than their counterparts who do not have this combination of genes.

Weight loss surgery is a highly effective treatment for patients with severe obesity, or a BMI of 40. A body mass index takes height and weight into account to measure body fatness. A BMI is a person's weight in kilograms divided by their height in meters squared. [Click here for more on body mass index, including how it's calculated using pounds and feet, as well as a handy BMI calculator you can use.]

"Recent data on the long-term effectiveness of bariatric surgery on BMI suggest that, for most patients, BMI will be maintained substantially below preoperative levels, though some patients regain weight and relapse toward morbid obesity," the authors conclude. This subgroup may carry genetic susceptibilities to obesity that overcome the effects of bypass surgery. "The identification of such susceptibility genes may therefore be important in identifying patients at high risk for postoperative weight gain," they add.

To that end, researchers at the Geisinger Clinic, Danville, Pa., assessed 707 morbidly obese adult patients with an average age of 45.9 and an average BMI of 51.2 who were undergoing gastric bypass operations at their facility. They scanned the genetic material, looking for two common single nucleotide polymorphisms (SNPs) previously found to be associated with obesity. The two obesity genes are called rs9939609 (FTO) and rs7566605 (INSIG2). In a nutshell, SNPs are variations that occur when a single building block of DNA is altered.

They showed that about 21 percent of the patients had two copies of one obesity-related SNP variant, 13 percent had two copies of the other SNP and 3.4 percent had two copies of both.

The average BMI among those with two identical copies of either obesity-related SNP were not significantly different from those who did not have two copies. But those with two copies of both SNPs, or two copies of one and one copy of the other, had significantly higher BMIs than the other groups. These individuals comprised less than 20 percent of the total group.

More research is needed to validate these findings and determine exactly how these genes influence obesity and/or the results of weight loss surgery. Stay tuned. — Denise Mann

Gastric Bypass Case Comparison Shows No Significant Difference in Complications Between Younger Patients and "Carefully Selected" Older Patients

CLEVELAND, June 2007 — Is gastric bypass surgery safe for older patients? A case review of 892 gastric bypass surgery patients found no statistically significant difference in post-surgery complications or death rates.

The patients, who had gastric bypass surgery sometime from 1998 to 2006, were divided into four groups with the aim of comparing outcomes for older people with those for younger people, as well as Medicare recipients with non-Medicare recipients. For example, 46 patients age 60-66 were in Group One, which was compared with 846 patients age 18 to 59 in Group Two. And 31 Medicare recipients age 31-66 were in Group Three, which was compared with the 861 non-Medicare recipients age 18-64 in Group Four.

The study documented age, gender, body mass index (BMI), time spent in the operating room, length of stay, other illnesses, complications and death.

"No mortality was seen in the older group (Group One) at 30 days, 90 days, or one year," reported the study authors. "Three deaths occurred within 30 days in the younger group (Group Two), with one additional death within one year." While Medicare patients had a greater average BMI, spent an average of 14 minutes longer in the operating room, and stayed an average of a day and half longer in the hospital, there was no significant difference from non-Medicare patients in complications or death.

The study authors concluded that age and Medicare status should not be the sole basis for denial of gastric bypass surgery. Peter T. Hallowell, MD, and other researchers at University Hospitals Case Medical Center and Case Western Reserve University School of Medicine, Cleveland, conducted the study.

More details are available in the study report published in the June 2007 issue of the journal Archives of Surgery.

FDA Panel Rejects Weight Loss Drug Rimonabant

WASHINGTON, D.C., June 2007 — An FDA advisory panel recommended in a unanimous vote that the agency not approve Zimulti (rimonabant) for sale in the United States.

The panel had concerns about potential side effects of the drug, made by French company Sanofi-Aventis, such as depression, sleep difficulties, and anxiety. Rimonabant was designed to block food craving signals in the brain, targeting the same brain receptors that trigger intense hunger after marijuana use. The manufacturer's studies showed patients lost 5% more weight than diet alone during a 12-month period and enjoyed a reduced waist size as well as higher levels of "good" cholesterol. But the FDA panel said obese patients were two times more likely to have suicidal thoughts (which Sanofi-Aventis disputes) or mental problems such as depression. The panel is also concerned about high drop-out rates in the clinical trials.

Sanofi-Aventis has proposed that patients be screened for depression and reassessed five times during the first year of using the drug. A final decision from the FDA may come in July.

In February 2006 the FDA rejected rimonabant for use as a smoking cessation drug, though at the time it did issue an "approvable" letter for its use in weight loss, on condition that more conclusive research be submitted.

[Page updated September 2008]