February 4, 1983

Heat annd Multiple Sclerosis

Author Affiliations

The Johns Hopkins University School of Medicine Baltimore

JAMA. 1983;249(5):591. doi:10.1001/jama.1983.03330290021017

To the Editor.—  The article entitled "Factors Associated With a Malignant or Benign Course of Multiple Sclerosis" (1982;248:856) was interesting, but I was disappointed by its inherent errors.First, the authors referred to eight publications in which "fever therapy" in multiple sclerosis (MS) was used. In fact, the quoted articles reported the effect of raising body temperature on neurophysiological studies as an adjunct to the diagnosis of MS and not as therapy, as suggested by Clark and colleagues.Second, the authors found that "malignant cases" of MS more frequently reported adverse responses to heat and concluded that heat exposure effected the course of the disease. This is a circuitous argument. In 1889, Uhthoff1 described temperature-induced transient deterioration in the visual acuity of patients with retrobulbar neuritis. It is now widely recognized that an increase in body temperature in MS may produce short-lived deterioration in neurological symptoms and signs.2