By DAVID TULLER, nytimes.com, March 4, 2011:
The study, published last month in The Lancet, reported that exercise and cognitive-behavioral therapy could help people with the illness. Advocates and some leading experts dismissed the findings and said the authors’ case definition was largely to blame.
The British scientists who conducted the research identified study participants based largely on a single symptom: disabling and unexplained fatigue lasting at least six months. But many researchers, especially in the United States, say that definition takes in many patients whose real illness is not the syndrome but depression — which can often be eased with psychotherapy and exercise.
The Lancet authors “have written their case definition to include both people with major depressive disorders and patients who clearly have received an insult to their immune systems and are depressed because they can no longer do things that they used to,” said Dr. Andreas Kogelnik, an infectious disease specialist in Mountain View, Calif., who treats many people with chronic fatigue syndrome.
In studying the condition, he and other researchers exclude patients whose only symptom is fatigue, however disabling, and instead rely on a case definition that includes other cognitive, neurological and physiological symptoms. Those symptoms, they believe, indicate a complex immune system disorder possibly caused by a virus or another agent.
Since 2009, studies have produced contradictory results over whether viruses related to mouse leukemia are associated with chronic fatigue syndrome, which is also called myalgic encephalomyelitis. A recent study found that people with the illness have distinct proteins in their spinal fluid, raising hope that a diagnostic test can someday be developed. Read more>>