Impact of Positive Airway Pressure on International Restless Legs Syndrome Score in Sleep Disordered Breathing

Studies have shown increased prevalence of restless legs syndrome (RLS) in sleep disordered breathing (SDB), however limited data have focused on the impact of SDB therapy on RLS. We hypothesize that positive airway pressure (PAP) will improve the International Restless Legs Syndrome (IRLS) score among SDB patients compared to patients without PAP.

Patients with AHI ≥ 5 who responded positively to a RLS qualifier question from January 2010 to May 2015 were included in this retrospective study. IRLS score was used to measure RLS symptom severity. Two-sample t-tests and one-way analysis of variance were used to compare changes in IRLS score and linear regression models were created to examine IRLS change with PAP use and PAP adherence (PAP usage ≥4 h nightly for ≥70% of nights), adjusting for potential confounders.

In 434 patients (51.9 ± 13.4years, 50.5% female, 77.6% Caucasian; 325 PAP, 109 control), IRLS scores improved from baseline to follow-up, with the PAP group achieving significant improvement after adjustment for covariates (difference in IRLS: -1.8 (CI -3.6,0.00), p = 0.050). In self-reported PAP adherent patients, IRLS improvement was greater than controls (-5.3 ± 7.4 vs. -2.7 ± 7.6 respectively, p = 0.045), and comparable to non-adherent patients (-5.3 ± 7.4 vs. -3.0 ± 7.0, p = 0.091).

Among SDB patients with a positive RLS qualifier, those who used PAP therapy achieved significantly greater improvement in IRLS scores than patients who did not use PAP, with more significant changes in the PAP adherent group. This is the first large clinical study to examine these relationships, providing a basis for future prospective interventional trials and informing clinicians of expected improvement in IRLS score in PAP treated SDB populations.