Significant association between systolic and diastolic blood pressure elevations and periodic limb movements in patients with idiopathic restless legs syndrome

Abstract

Objective: A new and unique methodology was developed to evaluate the association between periodic limb movements (PLMs) and nocturnal blood pressure (BP) excursions in patients with restless legs syndrome (RLS).

Methods: All data were collected at baseline of the ENCORE (Effects of Neupro on Cardiovascular Observations in Patients with Restless Legs Syndrome) study, a placebo-controlled polysomnographic study of rotigotine in patients with idiopathic RLS. Continuous beat-by-beat BP and heart rate assessments were performed during a full night of polysomnography. All BP elevations occurring with and without PLMs were systematically identified and analyzed.

Results: Patients (n = 89) had a mean total of 508.9 ± 405.7 PLMs, 788.4 ± 261.9 systolic BP elevations, and 349.7 ± 242.9 diastolic BP elevations during the night. Higher time-adjusted frequencies of systolic BP elevations [mean difference (95% confidence interval, CI): 543.0 (487.2, I); p <0.0001] and diastolic BP elevations (205.8 (169.3, I); p <0.0001) were observed with PLMs than without PLMs. A peak in the frequency of PLM onset coincided with BP elevation onset.

Conclusion: Our methodology allowed the first evaluation of the total number of nocturnal PLM-associated BP elevations occurring in patients with RLS. Our data clearly indicate an interdependence between BP elevations and PLMs, and they have clinical relevance as BP variability is a potential cardiovascular risk factor.

Keywords: Blood pressure elevations; Periodic limb movements; Polysomnography; Restless legs syndrome.