Restless legs syndrome is highly prevalent in patients with post-polio syndrome

Few studies have quantified the prevalence of restless legs syndrome (RLS) in patients with post-polio syndrome (PPS). Our objective was to assess the prevalence and severity of RLS in patients with PPS and to examine the demographic characteristics of this population.

This was a cross-sectional study conducted from April 2010 to May 2012 at the outpatient Neuromuscular Disorders clinic of Universidade Federal de São Paulo, São Paulo, Brazil. We evaluated 119 patients with PPS, consecutively recruited, and investigated for RLS based on the diagnostic criteria established by the International Restless Legs Syndrome Study Group (IRLSSG). Patients were evaluated with the Brazilian version of the IRLSSG severity scale.

The prevalence of RLS was 36% (n = 43; 32 women and 11 men). The ages at onset of RLS (median = 41 years) and PPS (median = 41 years) were concurrent, and the correlation between onset of symptoms of RLS and onset of symptoms of PPS was positive and very strong (Spearman r = 0.93, p = 0.01). The median RLS severity was 23 (range, 20-28). Low educational achievement and depression were predictive of RLS development.

In the largest population of patients with PPS studied to date, our results indicate a high prevalence of RLS, marked disease severity, and concomitant onset of both conditions in many patients with PPS. Further studies are needed to elucidate a possible pathophysiologic mechanism linking these two conditions. We suggest that all post-polio patients with sensory and motor complaints in the legs be investigated for RLS.