Is Restless Legs Syndrome De Facto Thyroid Disease?

Abstract

While a primary role in the pathogenesis of restless legs syndrome (RLS) has been attributed to dysfunction of the dopaminergic system and impaired iron metabolism (particularly in the central nervous system), it has been hypothesized that an imbalance between thyroid hormones and dopaminergic activity may be the starting point for all aspects of RLS. Although this hypothesis was proposed more than a decade ago, it has not yet been verified beyond doubt. The main aim of this study is to compare the prevalence of RLS in a population of patients with the most common thyroid gland diseases with a population of individuals with a healthy thyroid gland. The study included 237 participants divided into smaller groups according to the thyroid disease concerning them. Each participant had a laboratory diagnosis, an ultrasound scan and an assessment of the fulfilment of RLS criteria according to the International Restless Legs Syndrome Study Group (IRLSSG) criteria. The results obtained were subjected to statistical analysis. RLS is significantly more common in patients with known thyroid disease; Hashimoto’s disease, among others, manifests a 2.56× higher risk of a positive diagnosis for RLS than the general population. The association of RLS with thyroid disease is notable, although it is difficult to conclude unequivocally that there is a cause-and-effect relationship between the two. Further investigation into a potentially autoimmune cause of restless legs syndrome should be considered.

A Case Report of Grave’s Disease Presenting With an Episode of Restless Legs Syndrome

“…Another study reported that patients with thyroid disease were more likely to develop RLS [ 13 ]. Especially, the risk of RLS in patients with Hashimoto’s disease was 2.56 times higher than that in the control group [ 13 ].…”

“…Another study reported that patients with thyroid disease were more likely to develop RLS [ 13 ]. Especially, the risk of RLS in patients with Hashimoto’s disease was 2.56 times higher than that in the control group [ 13 ]. Additionally, the occurrence of RLS is notably more common in individuals with hypothyroidism compared to those without it, and the incidence of hypothyroidism is substantially greater in individuals who have RLS than in those who do not [ 14 ].…”

Correlates of Restless Legs Syndrome in Older People

“…Various comorbidities such as kidney disease, cardiovascular diseases, obstructive lung disease, diabetes mellitus, hypothyroidism, chronic liver disease, and neurological, rheumatological and respiratory disorders may accompany RLS [ 2 , 16 , 17 , 18 , 19 , 40 ]. In a cross-sectional study including 5324 subjects, high cholesterol and hypertension were associated with RLS [ 41 ].…”