MONDAY, Nov. 3, 2003 (HealthDayNews) -- In a rare tribute to blood-sucking, German physicians report leech treatment relieves the excruciating knee pain of arthritis more effectively than conventional drug therapy.
It might seem like a story from the days before Johannes Gutenberg invented movable type, but it appears as a sober report in the Nov. 4 issue of the Annals of Internal Medicine about a carefully controlled, thoroughly modern medical trial.
The study included 51 patients with severe arthritis-related knee pain. The 24 patients who had leeches applied to their joints reported an average reduction from 53.5 to 19.3 on a standard scale used to measure pain, while the reduction for those treated with diclofenac, a steroid drug, was much less, from 51.5 to 42.4, says the report from physicians at the Essen-Mitte Clinic in Essen.
The benefit of leech therapy wore out after a week, but "differences for function, stiffness and total symptoms remained significant for leech therapy until the end of the study," which lasted 30 days, the report says.
There are many possible reasons for the beneficial results, says Dr. Gunther Spahn, a professor of internal and integrative medicine who was a member of the study team.
"Leeches are a pharmaceutical company, injecting hirudin, bdeellin, eglin, proteases and many other substances [more than 30 described so far into the soft tissue]," Spahn says. "These substances may have an anti-swelling, anti-inflammatory and analgetic [pain-killing] effect. Also, the sucking itself may have a contra-irritatory effect on knee pain."
The study has continued, with more than 440 patients enrolled thus far and results expected by the end of the year, Spahn says. There now are about 70,000 leech treatments for pain in Germany each year, he says, but this is the first controlled trial to assess its effect.
"We hope to further standardize the treatment modalities and define the indications for it -- a treatment which is more than an alternative to analgesics," Spahn says.
In the United States, says Dr. Marc C. Hochberg, professor of medicine and epidemiology at the University of Maryland School of Medicine and author of an accompanying editorial, "I have no information about it [leech therapy] being done. I would hope it would not be done until more data demonstrating safety and efficacy, especially in comparison with standard therapy."
Hochberg's editorial finds many flaws in the German study. A major problem, he says, is that both the patients knew which treatment they were getting, which "raises concern about measurement bias," especially since the pain scores were based on patients' judgment.
A "more exciting" aspect of the study is that it might lead to better painkilling drugs based on analysis of molecules in leech saliva, Hochberg says.
"At the moment, however, on the basis of these data I am not ready to refer my patients with knee osteoarthritis for leech therapy," he writes.
Leeches are used medically in this country, but on a very limited basis, says Marie Bonazinga, president of Leeches USA Ltd., which sells them commercially.
"We do not sell to individuals," Bonazinga says. "We sell to plastic and reconstructive surgeons for use after surgery."
She declines to give more details about the leech trade on the grounds that it might arouse unwarranted interest in the general public.
Leeches had been used for centuries to get "the bad blood out," but the practice fell into disfavor by the 19th century.
More information
You can learn about the medicinal leeches from the University of Michigan, while the Arthritis Foundation has more on the disorder.
