AMA Morning Rounds: Findings shed light on essential tremor

In the New York Times (12/8, D7) Personal Health column, Jane Brody writes, "Recent studies have begun to unravel the mysteries of essential tremor," a condition characterized by "uncontrollable shaking...that is not due to some other condition." According to Dr. Elan D. Louis, of Columbia University, the progress is marked by "discoveries in three areas -- the brain, clinical findings, and genetics and environment." Researchers have "analyzed and compared...the brains of normal individuals" to those of patients with essential tremor, finding that "this is probably a family of diseases." Abnormal findings include "degenerative changes in the cerebellum," and "a messy arrangement of neurofilaments." Meanwhile, "two environmental toxins have been found to be elevated in tremor patients: lead and a dietary chemical called harmane that occurs naturally in plants and animals."