Restless Legs Syndrome (RLS) – Not So Harmless?

A fairly common disorder, Restless Legs Syndrome (RLS) is characterized by unpleasant sensations in the legs, with an uncontrollable urge to move them when at rest, to get relief.  It’s reported in various forms in 3% to 10% of the US population, and is considered an annoying, even distressing, problem, but harmless, apart from its production of exhaustion and daytime fatigue.  This may change, based on the study results presented at the American Academy of Neurology meeting in April.  

European researchers used data from a US IMS Healthcare database which had longitudinal records allowing a 2-year plus follow-up period.  Patients with clinical diagnoses of RLS seen by physicians more than twice before 2005 were matched an equal number of patients without RLS as controls.  Their average age was 55, and the female: male ratio was 2.3:1.

Each group comprised 3,485 patients.  Cardiovascular risk factors were analyzed for both groups over the 2 years.  The RLS group had increased likelihood of developing cardiovascular risk factors greater than that seen in the non-RLS control patients, as follows:

Cerebrovascular disease – 31% greater

Pulmonary vascular disease – 28% greater

Coronary heart disease – 20% greater

Peripheral artery disease - 19% greater

Any cardiovascular event – 12% greater

High blood pressure was the most common risk factor (it was seen in 48% of the entire collective) but it was used as a matching factor in selecting the controls, so there was no difference between the groups with regard to the likelihood of developing hypertension. 

The researchers conclude that their results reveal a significant association between a diagnosis of RLS and subsequent development of cardiovascular disease.  They therefore believe RLS patients should be monitored for cardiovascular conditions and new risk factors, such as high blood pressure.  There should be no need for alarm by RLS patients, as many cardiovascular risk factors can be corrected by appropriate lifestyle changes, and medication, if necessary.  Having an appropriate check-up by your doctor is just a wise precaution, with or without RLS.

Another report connecting RLS with cardiac changes (left ventricular hypertrophy) was reported at the American College of cardiology meeting last month.  Again, it was an association, but not evidence of a causal effect.  Patients in a sleep lab with more than 35 bursts of leg movements per hour had an almost two-fold increased risk of cardiac hypertrophy.  Something to be validated in a prospective study, says the investigator.