Chronic dopaminergic treatment in restless legs syndrome: does it affect the autonomic nervous system?

Sex differences in Parkinson's disease-related non motor symptoms: a focus on sleep problems

Parkinson's disease (PD) symptomatology differs between females and males, yet the contribution of sex on sleep problems needs further analysis. Here, we aimed to investigate sex-specific patterns in the relationship between sleep problems, assessed using the Parkinson's disease sleep scale (PDSS-2), non motor symptoms (NMS), measured by the NMS scale (NMSS), and health-related quality of life (HR-QoL), evaluated by the Parkinson's disease questionnaire (PDQ-39), in a large cohort of PD patients. One-hundred-fifty-four PD patients were included in the study. Female PD patients (n = 62) exhibited a higher prevalence of sleep problems than males (n = 92), with nocturnal motor-related sleep issues being the most frequent. Sleep disturbances differently correlated with a range of NMS between the two sexes. In females, sleep problems mostly correlated with pain; on the other hand, sleep disturbances were linked to a frailer phenotype characterized by global dysautonomia, perception disturbances, and impaired cognitive function in males. Whether female PD patients experienced a lower HR-QoL than males, sleep disturbances were associated with a worse HR-QoL in both sexes. In conclusion, sleep problems in PD differently burden the two sexes, suggesting possible different etiopathogenesis, diagnostic investigations, and possibly tailored approaches.

Pharmacological responsiveness of periodic limb movements in patients with restless legs syndrome: a systematic review and meta-analysis

STUDY OBJECTIVES

Periodic limb movements during sleep (PLMS) are a frequent finding in restless legs syndrome, but their impact on sleep is still debated, as well the indication for treatment. We systematically reviewed the available literature to describe which drug categories are effective in suppressing PLMS, assessing their efficacy through a meta-analysis, when this was possible.

METHODS

The review protocol was preregistered on PROSPERO (CRD42021175848), and the systematic search was conducted on and EMBASE (last searched on March 2020). We included original human studies, which assessed PLMS modification on drug treatment with a full-night polysomnography, through surface electrodes on each tibialis anterior muscle. When at least 4 studies were available on the same drug or drug category, we performed a random-effect model meta-analysis.

RESULTS

Dopamine agonists like pramipexole and ropinirole resulted the most effective, followed by l-dopa and other dopamine agonists. Alpha2delta ligands are moderately effective as well opioids, despite available data on these drugs are much more limited than those on dopaminergic agents. Valproate and carbamazepine did not show a significant effect on PLMS. Clonazepam showed contradictory results. Perampanel and dypiridamole showed promising but still insufficient data. The same applies to iron supplementation.

CONCLUSIONS

Dopaminergic agents are the most powerful suppressors of PLMS. However, most therapeutic trials in restless legs syndrome do not report objective polysomnographic findings, there is a lack of uniformity in presenting results on PLMS. Longitudinal polysomnographic interventional studies, using well-defined and unanimous scoring criteria and endpoints on PLMS are needed.

CITATION

Riccardi S, Ferri R, Garbazza C, Miano S, Manconi M. Pharmacological responsiveness of periodic limb movements in patients with restless legs syndrome: a systematic review and meta-analysis. J Clin Sleep Med. 2023;19(4):811-822.

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.

Screening autonomic functions in patients with restless legs syndrome: A case-control study in a tertiary care hospital

PURPOSE

The clinical importance of autonomic involvement in patients with restless legs syndrome (RLS) remains unclear. To our knowledge, no study has explored the relationship between autonomic dysfunction and disease-related variables in patients with RLS. Therefore, this study aimed 1) to determine the presence of autonomic symptoms in drug-naïve patients with RLS in comparison with healthy controls using Scales for Outcomes in Parkinson's disease-Autonomic (SCOPA-AUT) questionnaire and 2) to evaluate the possible associations of autonomic dysfunction with clinical factors in RLS.

METHODS

A total of 70 drug-naïve patients with RLS and 85 healthy volunteers were enrolled. The SCOPA-AUT questionnaire and Epworth Sleepiness Scale (ESS) scores were used to determine autonomic functions and sleep propensity, respectively. Moreover, the International Restless Legs Syndrome Study Group rating scale was used to evaluate disease severity in the patient group.

RESULTS

Compared with the control group, the RLS group had significantly higher subscale scores (gastrointestinal, urinary, cardiovascular, thermoregulatory, pupillomotor, and sexual [women]) and total scores of the SCOPA-AUT questionnaire (p < 0.05). In the patient group, there was a significant correlation between the total scores and subscale scores (gastrointestinal, cardiovascular, and thermoregulatory subscales) of the SCOPA-AUT questionnaire and disease severity. Moreover, ESS was positively correlated with the total scores and subscale scores (urinary, cardiovascular, and pupillomotor) of the SCOPA-AUT questionnaire.

CONCLUSION

Disease severity and daytime sleepiness may be related to autonomic dysfunction in RLS. Further studies focusing on autonomic functions in RLS are required to improve management strategies and clinical outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov. NCT04906486; May 28, 2021.

Systematic assessment of autonomic symptoms in restless legs syndrome

OBJECTIVES

To compare the clinical features of autonomic dysfunction using the SCOPA-AUT questionnaire in untreated patients with restless legs syndrome (RLS) with controls, to identify factors associated with more severe autonomic symptoms, and to assess the effect of medication in patients.

METHODS

The SCOPA-AUT questionnaire that evaluates cardiovascular, gastrointestinal, urinary, thermoregulatory, pupillomotor, and sexual dysfunctions was completed by 409 consecutive untreated patients with RLS (54.1 ± 14.5 y.o; 265 women) and 331 controls (59.0 ± 17.0; 161 women). Clinical and polysomnographic data were assessed in all patients. A subgroup of 57 patients were evaluated a second time after treatment (mostly dopaminergic agonist) after an interval of 0.88 ± 1.42 year.

RESULTS

Compared to controls, untreated patients with RLS were younger, more often women, obese, with increased cardiovascular diseases (CVD). The SCOPA-AUT total score was higher in patients than controls in unadjusted and adjusted models. Patients had more autonomic symptoms in all subdomains of the scale (except for sexual dysfunction in men). These results were confirmed in a subgroup of 259 cases and age-sex-matched controls. Female gender, obesity, RLS severity, diabetes mellitus, CVD, sleepiness, insomnia and depressive symptoms but neither periodic legs movements during sleep (PLMS) nor objective sleep parameters were associated with high scores. Despite RLS and PLMS improvement, medication did not change total and subdomain scores.

CONCLUSIONS

Patients with RLS have frequent and large spectrum of autonomic symptoms, without effect of PLMS, sleep fragmentation and medication. These results suggest a global autonomic dysfunction in RLS that should be assessed more systematically in severe patients.

Neurological Sleep Disorders and Blood Pressure: Current Evidence

Hypertension is a major determinant of cardiovascular morbidity and mortality and is highly prevalent in the general population. While the relationship between sleep apnea and increased blood pressure has been well documented, less recognized is emerging evidence linking sleep-related movement disorders such as restless legs syndrome/periodic limb movements of sleep and sleep-related bruxism with blood pressure (BP) dysregulation and hypertension. There is also recent literature linking narcolepsy-cataplexy with elevated BP and altered pressor responses, and there are data suggesting abnormal BP control in rapid eye movement sleep behavior disorder. It is thought that neural circulatory mechanisms, sympathetic activation in particular, comprise the predominant mediator underlying elevated BP in these neurological sleep disorders. There is very limited evidence that treating these sleep disorders may be beneficial in lowering BP primarily because this question has received very little attention. In this review, we discuss the potential pathophysiologic mechanisms underlying elevated BP in restless legs syndrome/periodic limb movements of sleep, sleep-related bruxism, narcolepsy-cataplexy, and rapid eye movement sleep behavior disorder. We also examine the relationship between these sleep disorders and elevated BP and the impact of treatment of these conditions on BP control. Last, we discuss gaps in the literature evaluating the associations between these sleep disorders and elevated BP and identify areas for further research.

Effect of Adaptive Servo-Ventilation on Periodic Limb Movements in Sleep in Patients With Heart Failure

Periodic limb movements in sleep (PLMS) are associated with adverse outcomes in patients with heart failure (HF). The aim of this study was to investigate whether PLMS change in response to adaptive servo-ventilation (ASV) for central sleep apnea (CSA) in patients with HF. We examined polysomnographic studies conducted between 2010 and 2014 at Mayo Clinic, Rochester, Minnesota (n = 14,444). In those, 314 of 579 patients with CSA completed the sleep study with a protocol that began with diagnostic polysomnography, followed by continuous positive airway pressure, and, for persistent CSA, by ASV titration. Patients with HF (n = 118) had a significantly higher median PLM index compared with those without HF (n = 196): 33.7 versus 6.1 events/h (p <0.001). HF was associated with a significant PLM arousal index (PLMAI) increase from diagnostic trial to ASV (odds ratio [OR]  = 1.79, p = 0.032) after adjusting for demographics, co-morbidities and medications. In patients aged >68 years, HF was associated with PLMI and PLMAI increases during ASV (OR  = 2.16, p = 0.016 and OR  = 2.05, p = 0.024), which persisted in multivariable models (OR  = 2.36, p = 0.025 and OR  = 2.33, p = 0.026). In multivariable analysis, patients with ejection fraction ≤45% had higher odds of increased PLMAI during ASV than those with ejection fraction >45% (OR  = 1.98, p = 0.022). In conclusion, PLMS may increase in HF patients after suppression of CSA by ASV. Whereas the clinical significance of increased post-ASV PLMS in HF prognosis needs to be determined, these increases may contribute to worsening outcomes in HF patients with CSA treated with ASV.

Patients with primary restless legs syndrome have higher prevalence of autonomic dysfunction and irritable bowel syndrome

INTRODUCTION

Given the limited data on autonomic dysfunction in patients with primary restless legs syndrome (pRLS), we compared autonomic dysfunction and presence of irritable bowel syndrome (IBS) between patients with pRLS and control patients.

METHODS

Consecutive adult drug-naïve patients with pRLS, and age- and gender-matched healthy control patients were enrolled in this study. Diagnoses, based on validated self-reported questionnaires, were made using the following guidelines: Rome III classification system for functional gastrointestinal disorders for IBS; Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI) for the presence of anxiety and depression, respectively; Pittsburgh Sleep Quality Index (PSQI) for severity of sleep disturbances; and Scales for Outcomes in Parkinson's disease-Autonomic (SCOPA-AUT) for autonomic dysfunction.

RESULTS

There were 88 patients with pRLS (18 male, 70 female) and 128 control patients (40 men, 88 women). The mean age of the pRLS patients and control patients was 50.3 ± 9.3 years and 49.7 ± 8.2 years, respectively. Overall, 41 (46.6%) of the patients with pRLS and 16 (12.5%) of the control patients had IBS. Among patients with pRLS, IBS was significantly more common and the total autonomic SCOPA-AUT scores were higher than those found among control patients. Among pRLS patients with IBS, total autonomic SCOPA-AUT, PSQI, BAI and BDI scores were significantly higher than among pRLS patients without IBS. The presence of IBS did not affect the severity of restless legs syndrome.

CONCLUSION

The presence of autonomic nervous system impairment in patients with pRLS and the strong link between IBS and pRLS merit further, more extensive investigation.