Outcome of restless legs severity after continuous positive air pressure (CPAP) treatment in patients affected by the association of RLS and obstructive sleep apneas

Background and purpose: The association of obstructive sleep apnea syndrome (OSAS) and restless legs syndrome (RLS) has been reported in the literature for many years. Nevertheless, this pathological association has not yet been extensively studied and many questions remain unanswered. The primary concern of this study is to evaluate the influence of nasal continuous positive airway pressure (n-CPAP) therapy on daytime sleepiness and fatigue as well as the presence of a possible long-term beneficial effect on RLS severity and, secondarily, to ascertain the clinical, neurophysiological and polysomnographic characteristics of a group of patients with both OSAS and RLS. Patients and methods: All patients had a diagnostic polysomnography (PSG) and a second polysomnography for titration of n-CPAP. Laboratory tests (blood glucose, serum ferritin), body mass index (BMI) calculation and a neurophysiological evaluation (auditory P300 and electroneuromyography) were done. The Epworth Sleepiness Scale (ESS) and the Pichot's questionnaire of fatigue/depression (PIC) were applied to all patients before and after three months of n-CPAP treatment. The International Restless Legs Syndrome Study Group rating scale (IRLS) was applied before and after n-CPAP. Results were compared. Results: The ESS scores decreased from 10.64 +/- 4.83 at baseline to 7.41 +/- 3.5 (P < 0.05). PIC scores decreased from 16.65 +/- 7.27 to 10.12 +/- 6.40 (P<0.01). IRLS scores decreased from 17.60 +/- 7.11 before to 12.52 +/- 9.25 after n-CPAP (P<0.05). Conclusions: Our findings suggest that not only fatigue and sleepiness but also the severity of RLS show a favorable response to n-CPAP in the group of patients with OSAS and RLS. (C) 2005 Elsevier B.V. All rights reserved.