New Immune System Link Found for Narcolepsy

Dec. 9, 2004 -- A new discovery about the cause of narcolepsy may have the potential to improve diagnosis and treatment of the sleep disorder.

New research shows that a certain antibody (disease-fighting part of the immune system) may serve as a marker for narcolepsy.

Narcolepsy is a disabling sleep disorder that causes excessive daytime sleepiness and is linked to abnormal hormone concentrations and changes in nervous system activity. Researchers say diagnosing narcolepsy is difficult and is currently done mostly on the basis of a person's symptoms. It often requires repeated testing.

This study was only preliminary, but if more studies confirm these results, researchers say screening for this antibody may allow an earlier and more definitive diagnosis.

New Clue About Causes of Narcolepsy

In the study, which appears in the Dec. 11 issue of The Lancet, researchers examined the effects of injecting antibodies taken from nine people with narcolepsy into mice.

They found that mice injected with the antibodies from narcoleptics developed narcolepsy-like symptoms, but mice injected with antibodies from nine people who didn't have narcolepsy did not develop such symptoms.

Researchers say the findings indicate that the antibody is a sensitive and specific marker for the condition and might lead to better diagnosis and eventually treatment of narcolepsy.

In an editorial that accompanies the study, Merrill S. Wise of Baylor College of Medicine in Houston, says that if these findings are confirmed, it will open "an exciting new chapter in the narcolepsy story."