The impact of treatment of periodic limb movements in sleep on blood pressure in patients with and without sleep apnea.

Improving sleep quality in patients with obstructive sleep apnea (OSA) by positive airway pressure therapy is associated with a decrease of blood pressure (BP). It remains elusive, whether treatment of sleep disturbances due to restless legs syndrome with symptomatic periodic limb movements in sleep (PLMS) affects BP as well. The present study provides first data on this issue. Retrospective study on patients undergoing polysomnography in a German University Hospital. Inclusion criteria were first diagnosis of restless legs syndrome with PLMS (PLM index ≥ 15/h and PLM arousal index ≥ 5/h) with subsequent initiation of levodopa/benserazide or dopamine agonists. Exclusion criterion was an initiation or change of preexisting positive airway pressure therapy between baseline and follow-up. BP and Epworth sleepiness scale were assessed at two consecutive polysomnographies. After screening of 953 PLMS data sets, 114 patients (mean age 62.1 ± 12.1 years) were included. 100 patients (87.7%) were started on levodopa/benserazide, 14 patients (12.2%) on dopamine agonists. Treatment was associated with significant reductions of PLM index (81.2 ± 65.0 vs. 39.8 ± 51.2, p < 0.001) and ESS (6 [interquartile range, IQR, 3-10.5] vs. 5 [IQR 3-10], p = 0.013). Systolic BP decreased from 132.9 ± 17.1 to 128.0 ± 15.8 mmHg (p = 0.006), whereas there was no significant change of diastolic BP (76.7 ± 10.9 vs. 75.1 ± 9.2 mmHg, p = 0.15) and heart rate (71.5 ± 11.9 vs. 71.3 ± 12.7, p = 0.84). The number of antihypertensive drugs remained unchanged with a median of 2 (IQR 1-3, p = 0.27). Dopaminergic treatment of PLMS is associated with an improvement of sleep quality and a decrease of systolic BP comparable to treatment OSA.