New & Interesting (2 November 2009)

interesting-news-iconThe “New & Interesting” series is a biweekly compilation of select research findings, news articles, and random tidbits in bullet-point format. The entries are highly abbreviated, but provide links to the original articles or abstracts if you desire to read further.

General Articles

  • Video games may cause kids to suffer finger and wrist pain (WebMD)
  • Researchers at the University of Pittsburgh School of Medicine employed high-sensitivity MRI scanners to evaluate the effect of glucosamine on progression of knee osteoarthritis. They “did not find any evidence that glucosamine can prevent or slow joint damage in individuals with mild to moderate knee pain.” The results from the study resemble findings from an earlier meta-analysis that did not demonstrate substantive symptomatic benefit from the use of chondroitin. (WebMD)
  • Universal health coverage in Massachusetts does not reduce visits to the Emergency Department (American Medical News)

Technical Articles

  • Prophylactic administration of acetaminophen for febrile reactions at the time of vaccination reduces antibody responses to vaccine antigens in children (Lancet)
Does knuckle cracking cause arthritis?

Coincident with the prestigious Nobel Prizes awarded each year are their parody counterparts: the Ig Nobel Prizes (a play on the words “ignoble” and “Nobel”). The honors are bestowed to individuals who demonstrate notable achievements that “first make people laugh, and then make them think.” The awards ceremonies take place each October at the Sanders Theater of Harvard University and include genuine Nobel Laureates presenting the awards.

This year’s Ig Nobel Prize in Medicine goes to Donald L. Unger of Thousand Oaks, California, for investigating whether knuckle cracking causes arthritis. The premise of his research, published in Arthritis & Rheumatism, was to test the validity of admonitions from “renowned authorities” (i.e., his mother, several aunts, and mother-in-law) that cracking his knuckles would lead to arthritis. Over the course of 50 years, Unger cracked the knuckles of his left hand at least twice daily, while sparing his right hand to serve as a control. At the end of the 50-year observation period, Unger did not detect any difference between both hands. He concluded that “there is no apparent relationship between knuckle cracking and the subsequent development of arthritis of the fingers.”

In light of the present evidence, Unger now questions whether other “parental beliefs”, such as the importance of eating spinach, are similarly flawed.

Efficacy of Antidepressants for Fibromyalgia

A German group recently evaluated the use of antidepressants for
fibromyalgia syndrome (FMS), a chronic pain disorder affecting
multiple points of tenderness. They performed a meta-analysis of
randomized controlled trials published through August 2008. The
studies included randomized placebo-controlled trials involving
tricyclic/tetracyclic antidepressants (TCAs), selective serotonin
reuptake inhibitors (SSRIs), combined serotonin and noradrenaline
reuptake inhibitors (SNRIs), and monoamine oxidase inhibitors (MAOIs).

The study noted a strong association between the use of antidepressants and reduction in pain, fatigue, depression, and sleep disturbances. There was also an improved health-related quality of life. The effects were most notable with TCAs, less with MAOIs, and least with SSRIs or SNRIs.

Source: Hauser W, Bernardy K, Uceyler N, Sommer C. Treatment of fibromyalgia syndrome with antidepressants. JAMA 2009;301:198-209.

Does Chondroitin Work for Arthritis?

Knee RadiographSince the FDA (Food and Drug Administration) does not regulate dietary supplements as stringently as pharmaceutical drugs, manufacturers of the former can market their products with untested and unsupported claims. While some claims border on fantasy and may breach ethical standards (”pill that cures all cancers”), most claims are plausible. Calcium and vitamin D supplements may build bones. Iron sulfate may help with some forms of anemia. But, do we know whether the supplements truly provide their advertised effect?

Chondroitin sulfate and glucosamine have long been marketed as substances to alleviate the arthritides. This is a reasonable conjecture, given that chondroitin sulfate is a polysaccharide found in joint cartilage. One would logically assume that oral supplementation of this substance would help replenish eroded joints. Even the Mayo Clinic states that “consensus of expert and industry opinions support the use of chondroitin and its common partner agent, glucosamine, for improving symptoms and arresting (or possibly reversing) the degenerative process of osteoarthritis.” The Mayo Clinic, however, does not go so far as to fully endorse chondroitin use. It admits that “(s)afety and effectiveness have not always been proven”.

So, does it work? A meta-analysis published this week in the Annals of Internal Medicine hopes to address the question and controversy. The study included 22 independent research trials examining the efficacy of chondroitin use with osteoarthritis of the knee or hip. Twenty trials (3846 patients) had sufficient data to calculate effect of chondroitin use on joint pain. Twelve trials were used to assess adverse events, and 5 trials reported radiologic measurements of joint space width.

The authors understand the limitations of their study and concede to the variable experimental and reporting methodologies among the trials. They nevertheless assert that the “large-scale, methodologically sound trials indicate that the symptomatic benefit of chondroitin sulfate is minimal or nonexistant. Use of chondroitin in routine clinical practice should therefore be discouraged.” On the flip side, they did not identify any significant adverse effect. I suppose one downside of continued use would be wasted money.

In our subjective world, evidence-based medicine does not always determine our health choices. As long as there are proponents of chondroitin use, and deep pockets to keep the marketing campaigns moving, the sale of chondroitin and similarly questionable supplements will retain their presence on store shelves. At least we have the freedom of choice.

  • Source
  • Reichenbach S, Sterchi R, Scherer M, Trelle S, Burgi E, Burgi U, Dieppe PA, Juni P. Meta-analysis: chondroitin for osteoarthritis of the knee or hip. Ann Intern Med 2007;146:580-90.

Technorati Tags: