Hookworm (Photo: CDC)

By Katherine Kahn, Contributing Writer
Health Behavior News Service

Purposely infecting patients with hookworms or whipworms to treat hay fever and other immune-related diseases has been experimented with since the 1970s.

A new review by The Cochrane Library concludes that current evidence doesn’t yet support the use of this therapy.

However, worm therapy does appear to be safe, the review’s lead author says.

“Allergic diseases affect hundreds of millions of people worldwide, especially in industrialized countries,” says review author Ashley Croft, M.D., a public health physician at the headquarters of the Surgeon General, Whittington Barracks, in Lichfield, UK. “Existing treatments for allergies, which mostly involve pharmacotherapy, are often expensive, dangerous, or ineffective. If worm therapy can be shown to be effective and safe, it will represent an important new clinical option for treatment.”

Croft theorizes that worm therapy might work if having intestinal worms “‘tones up’ the immune system of their human hosts, so that the host stops being over-responsive to common allergens. This helps the worms avoid detection and destruction by the host’s immune system.”

“It’s generally appreciated that in the 20th century a whole series of immunological diseases have emerged out of nowhere,” Weinstock explains, including hay fever, asthma, inflammatory bowel diseases, and multiple sclerosis. “Why did these diseases emerge? If you look around the world, these diseases are fairly common in industrialized countries, but in less developed countries, they are relatively rare.”

 Key Points

• Since the 1970s, worm therapy has been used as an alternative treatment for hay fever under the assumption that it might calm overactive immune systems.

• No long-term studies have been conducted to demonstrate that worm therapy relieves hay fever symptoms.

• An evidence review of available studies of worm therapy shows no benefit for hay fever sufferers, and that while safe it may cause minor digestive problems.

The cause, Weinstock believes, is the tremendous improvement in hygiene—and that includes lack of exposure to intestinal worms, such as hookworms and whipworms. “Up until the 20th century, everybody had worms,” Weinstock says.

The lack of worm infections in modern societies, Weinstock conjectures, has led to over-reactive immune systems and an increase in immune-related diseases.

Croft’s review examined evidence from two placebo-controlled, double blinded studies that enrolled a total of 130 adults who had either intermittent or persistent allergic rhinitis.

One study used hookworm larvae, which enter through the skin and travel to the intestines and the other study used pig whipworm eggs that participants swallowed.

Participants who used worm therapy had no reduction in hay fever symptoms or percentage of days when symptoms were minimal. They also had no changes in lung function or quality of life scores.

Croft cautions that these studies are too small to truly evaluate effectiveness. “It did come as a surprise, therefore, that we found that people with allergic rhinitis who took worms were less likely to have to take tablets as rescue medication during the grass pollen season.”

Weinstock also says that the studies to date haven’t been designed very well and says it was surprising researchers found any response at all since the study follow-up times were too short.

“To treat an allergy, you probably have to have a treatment strategy that’s at least six months long,” before evaluating effectiveness, he says. The studies ran for only three months and six months, respectively, after initiating worm therapy.

“Our main finding was that worm therapy is safe,” says Croft. “In participants who took worms there were some gastrointestinal side effects, such as abdominal pain and diarrhea, but these were transient and were not so severe as to cause people to drop out of the trials.”

Croft says that there is enough evidence to support continued research in worm therapy. “Clinical trials in worm therapy are not expensive to run and the potential benefits from this new form of therapy are very great,” he says.

Health Behavior News Service is part of the Center for Advancing Health

The Health Behavior News Service disseminates news stories on the latest findings from peer-reviewed research journals. HBNS covers both new studies and systematic reviews of studies on (1) the effects of behavior on health, (2) health disparities data and (3) patient engagement research. The goal of HBNS stories is to present the facts for readers to understand and use for themselves to make informed choices about health and health care.

Pancreas (head, body, and tail of the pancreas, and the pancreatic duct) and nearby organs and structures (duodenum, common bile duct, and small intestine). - Don Blis/NCI

From the NCI Cancer Bulletin

Researchers have discovered a physical mechanism that prevents chemotherapy from reaching pancreatic cancer cells, as well as a way to reverse that mechanism.

Dr. Sunil Hingorani of the Fred Hutchinson Cancer Research Center and his colleagues reported their results March 19 in Cancer Cell.

Pancreatic adenocarcinoma, the most common type of pancreatic cancer, is notoriously resistant to chemotherapy and radiation therapy, leading to an overall 5-year relative survival rate of less than 5 percent.

Using mice with tumors that are genetically similar to human pancreatic adenocarcinomas, the researchers found that, as the tumors grow, a thick matrix develops and surrounds the tumors’ cells.

The matrix exerts tremendous pressure on the tumors—pressure that greatly exceeds the normal pressure found within blood vessels—causing the tumors’ blood vessels to collapse.

This collapse prevents chemotherapy drugs in the blood stream from reaching the tumor cells.

Dr. Hingorani and his colleagues identified a substance called hyaluronic acid that forms a large part of this pressurized matrix.

When they treated the mice with an enzyme called PEGPH20, which breaks down hyaluronic acid, the pressure within the tumors returned to normal, and the blood vessels regained their normal shape and function.

When the researchers treated mice with a combination of PEGPH20 and the chemotherapy drug gemcitabine, 83 percent of tumors within the pancreas shrank after only one cycle of treatment, and all tumors shrank after three cycles.

Similar responses were seen in metastatic tumors. Mice that received the combination therapy survived almost twice as long as mice that received PEGPH20 plus a placebo.

“When able to penetrate the tumor bed, gemcitabine can indeed be an effective agent against this disease,” wrote the authors. An early phase clinical trial is testing the combination of PEGPH20 and gemcitabine in people with metastatic pancreatic cancer.

To learn more about pancreatic cancer read the NCI pamphlet What You Need to Know About Cancer of the Pancreas.

The NCI Cancer Bulletin is an award-winning biweekly online newsletter designed to provide useful, timely information about cancer research to the cancer community. The newsletter is published approximately 24 times per year by the National Cancer Institute (NCI), with day-to-day operational oversight conducted by federal and contract staff in the NCI Office of Communications and Education. The material is entirely in the public domain and can be repurposed or reproduced without permission. Citation of the source is appreciated.

Ready to be the next weight-loss success story?

Let your new life begin!

I lost 90 pounds with the Lap-Band!

Sounds tempting, doesn’t it?  The Food and Drug Administration (FDA) has seen many claims similar to the ones above, but there’s a catch.

There can be serious risks with the weight-loss surgery and medical implant promoted by these ads, so FDA is taking action.

How Gastric Banding Works -- A surgeon places a circular silicone band around the upper part of the stomach, creating a small pouch. The narrowed opening between the pouch and the rest of the stomach controls how fast food passes to the lower part of the stomach. The band is connected with tubing to a button-like part (port) placed close to the skin above the stomach. A doctor can adjust the band, without surgery, by inserting a needle through the skin into the port to add or remove fluid in the band. This changes the size of the opening, which controls how fast food passes into the lower stomach. The band limits the amount of food that can be eaten at one time, helping people to feel full sooner and eat less.

FDA has warned eight surgical centers and the marketing firm 1-800-GET-THIN LLC in California about misleading advertising of the Lap-Band—a device implanted in a surgery called gastric banding to help adults eat less and lose weight.

The ads—splashed on billboards, bus placards, newspaper advertisements, the Internet and elsewhere—feature slender, smiling men and women claiming they lost massive amounts of weight and gained control of their lives after Lap-Band surgery.

“FDA’s concern is that these ads glamorize the Lap-Band without communicating any of the risks,” says Steven Silverman, director of the Office of Compliance in FDA’s Center for Devices and Radiological Health. “Consumers, who may be influenced by misleading advertising, need to be fully aware of the risks of any surgical procedure.”

By federal law, product advertising for certain medical devices, such as the Lap-Band, must contain relevant warnings and information about precautions, side effects, and contraindications (medical reasons that make a treatment inappropriate).

FDA’s warning letters direct the California marketing firm and surgical centers to pull their misleading ads and to notify FDA within 15 working days of action taken to correct them.

Two Gastric Bands Approved

FDA has approved two gastric bands: Lap-Band, by Allergan Inc., and Realize Adjustable Gastric Band, by Ethicon Endo-Surgery Inc. These devices are implanted around the upper part of the stomach to create a “pouch.” The small pouch limits the amount of food that can be eaten at one time, making you feel full faster and potentially lose weight.

Both bands are approved for use in adults age 18 and older who have not lost weight with non-surgical methods, such as diet, exercise or behavior modification, and have

• a body mass index (BMI) of at least 40. (BMI is a measure of body fat based on an adult’s height and weight. A 5-foot-6-inch person weighing 248 pounds has a BMI of 40.)

or

• a BMI of at least 35 (217 pounds at 5-foot-6 inches) and at least one health condition linked to obesity, such as diabetes or high blood pressure.

Allergan’s Lap-Band is also approved for those with a BMI of 30 to 34 who have a health condition related to their obesity.

The Risks

“Surgery itself has risks, including death, and those risks are heightened for people who are obese,” says Herbert Lerner, M.D., a general surgeon and supervisory medical officer at FDA.

There are risks after the surgery, too, including

• nausea and vomiting
• difficulty swallowing
• gastroesophageal reflux disease (GERD)
• upset stomach or pain
• stretching of the stomach pouch
• stretching of the esophagus
• moving of the gastric band, requiring another surgery to reposition it
• erosion of the band through the stomach wall and into the stomach, requiring another surgery

“Most people lose weight with the gastric band,” says Lerner. “However, one should not assume that a gastric band is a permanent device. A good number of people require another operation to reposition, replace or remove the gastric band sometime during their life due to complications or because they have not lost weight.”

No Binging Allowed

Gastric banding requires a drastic diet change—you need to eat small portions frequently to prevent complications and ensure weight loss, says Lerner. “If you eat or drink more than your stomach pouch can hold, the pouch will stretch and food may back up into the esophagus. You may have nausea and vomiting, and require an adjustment of the band.”

And if patients eat a lot of fattening foods or drink milkshakes or other high-calorie liquids, they may not lose a lot of weight.

If you are considering gastric banding, it is important that you read the information booklet provided by your surgeon and discuss any questions you have with your surgeon before deciding to have surgery. If your surgeon does not provide you with a booklet, ask for one.

This article appears on FDA’s Consumer Updates page, which features the latest on all FDA-regulated products.

Dec. 13, 2011

For More Information

By Michelle Andrews

Jackie Risley, before and after her bariatric surgery (Photos provided by Risley)

As obesity among young people continues to rise, a growing number of clinicians and researchers say that weight-loss surgery may be their best chance to take off significant weight and either correct or avoid conditions like diabetes and heart disease, which often go hand-in-hand with obesity.

But although health plans frequently cover bariatric surgery in adults, insurance coverage for the procedure in patients under age 18 is spotty.

Experts in pediatric obesity say that caution is warranted and that insurers shouldn’t just rubber-stamp such surgery in adolescents.

But they say emerging research may lead to more coverage for young people.