March 16, 2005 - Sleepwalking may be a rare but previously unrecognized symptom of hyperthyroidism, according to a new study.
Researchers say they've documented at least eight cases in which people started sleepwalking at the same time their hyperthyroidism emerged. Although the exact relationship between hyperthyroidism and sleepwalking is unclear, they say the results suggest that there is a cause-and-effect relationship between the two conditions.
is a common disorder in which the thyroid gland produces too much thyroid hormone. Thyroid hormones regulate metabolism and how the body turns food into energy, and they influence a variety of other processes in the body.
are a common symptom of hyperthyroidism, but researchers say that until now sleepwalking has not been viewed as a symptom of the disorder. Other known symptoms of hyperthyroidism include nervousness, weight loss, heat intolerance, irritability, fatigue, insomnia, and restlessness.
Hyperthyroidism May Lead to Sleepwalking
In the study, which appears in a recent issue of Endocrine Practice, researchers describe eight cases in which patients reported starting to sleepwalk at the same time their hyperthyroidism was diagnosed.
In each case, researchers say the sleepwalking disappeared once the hyperthyroidism was successfully treated. In addition, two of the patients began sleepwalking again after their hyperthyroidism became poorly controlled because of failure to take their medications as prescribed.
Researchers say none of the patients had a family history of sleepwalking or night terrors, which are commonly associated with other causes of sleepwalking.
They propose that the combination of (the early parts of the sleep cycle before intense dreaming occurs) and resulting fatigue caused by hyperthyroidism may result in sleepwalking in a select group of people with the disorder.
But they say more research is needed to better understand and confirm this unusual potential side effect of hyperthyroidism and determine its prevalence among people with hyperthyroidism.