Sleepwalking may be a symptom of an overactive thyroid
Mar. 22, 2005
MediResource

An overactive thyroid may lead to sleepwalking, say the authors of a small study documenting this previously unrecognized symptom.

Researchers at the National Center for Diabetes, Endocrinology and Genetics in Amman, Jordan, are reporting eight cases where the start of sleepwalking episodes coincided with the onset of hyperthyroidism, a common disorder whereby the thyroid gland produces an excess of hormones.

The thyroid gland, which is located in the neck, produces hormones that regulate the body's metabolism. Symptoms of an overactive thyroid often include increased heart rate, high blood pressure, excessive sweating and weight loss.

While sleepwalking hasn't previously been documented as a symptom of hyperthyroidism, the researchers say their study points to a "cause-and-effect relationship" because none of their subjects had a family history of sleepwalking or had experienced episodes prior to the onset of their thyroid condition. What's more, the sleepwalking episodes stopped after the subjects got their thyroid condition under control using medications, and started up again in two subjects who failed to properly take their thyroid medication as prescribed.

While more research needs to be done before broad conclusions about the relationship between sleepwalking and hyperthyroidism can be reached, the researchers noted that the link only appeared to exist in hyperthyroid cases caused by Graves' disease or toxic goiter. Graves' disease occurs when the thyroid becomes overstimulated by the immune system, while toxic goiter occurs when abnormal tissues inside the thyroid stop responding to a hormone that normally regulates the gland.

Other causes of hyperthyroidism include thyroid inflammation, using medications that contain high amounts of iodine, thyroid cancer, and problems with the pituitary gland, which produces the hormone that regulates thyroid activity.

Hyperthyroidism is usually treated with oral medication, though in some cases surgical removal of the thyroid gland may be necessary. Left untreated, an overactive thyroid can cause muscle loss, liver enlargement and even fatal heart strain.

Results of the study were published in the journal Endocrine Practice.