The History of RLS

One of the earliest descriptions of Restless Legs Syndrome (RLS) is found in a seventeenth century book by Sir Thomas Willis, an English physician who served under King Charles II.¹ Willis documented cases of patients with RLS symptoms as follows:

“Wherefore to some, when being a Bed they betake themselves to sleep, presently in the Arms and Leggs, Leapings and Contractions of the Tendons, and so great a Restlessness and Tossings of their Members ensue, that the diseased are no more able to sleep, than if they were in a Place of greatest Torture.”

Thomas Willis
Extract from The London practice of physick. London: Basset and Crooke, 1685.

Our current understanding of RLS began with Professor Karl-Axel Ekbom, a Swedish professor, who gave the first scientific description of the condition and coined the term ‘Restless Legs Syndrome’ in the 1940s following his thesis entitled: “Restless Legs, a Clinical Study of a Hitherto Overlooked Disease in the Legs”. Over a period of several years, Ekbom published extensively on RLS and his papers are still quoted by researchers in the field today.  It is because of Ekbom’s discovery that RLS is also referred to as ‘Ekbom disease’.

Work on a causative link between iron deficiency and RLS, originally proposed in the 1950s, was later researched by Professor Richard P. Allen at Johns Hopkins University, U.S.A.¹ More recent research has shown a genetic link between RLS and certain chromosomes and some data suggest a more than 50 percent increase in risk for RLS for some genetic variants.^2,3

However, what causes RLS is still not fully understood and more research is required to fully understand the condition.

This timeline highlights the key milestones in RLS discoveries from first description of the condition to first approval of medicines for the symptomatic treatment of idiopathic (primary) RLS:

References

1. Allen RP et al. Restless Legs Syndrome: a review of clinical and pathophysiologic features. J Clin Neurophysiol 2001; 18(2): 128–147.
2. Winkelmann J et al. Genome-wide association study of Restless Legs Syndrome identifies common variants in three genomic regions. Nature Genetics 2007: 39: 1000-1006.
3. Stefansson H et al. A genetic risk factor for periodic limb movements in sleep. NEJM 2007; 357: 639-647.
4. Konofal E et al. Two early descriptions of Restless Legs Syndrome and periodic leg movements by Boissier de Sauvage (1763) and Gilles de la Tourette (1898). Sleep Med 2008. doi:10.1016/j.sleep.2008.04.008. [Epub ahead of print]