Restless Legs Syndrome and Other Common Sleep-Related Movement Disorders

Evaluation of sleep position shifts in patients with obstructive sleep apnea syndrome with the use of a mandibular advancement device

Background

The aim of this study was to evaluate position shifts during sleep of patients with obstructive sleep apnea (OSA) syndrome both with and without the use of a mandibular advancement device (MAD).

Methods

In total, 73 adult Caucasian patients diagnosed with obstructive sleep apnea syndrome confirmed by polysomnography were retrospectively enrolled. Inclusion criteria were as follows: age >20 years, body mass index <34 kg/m2, polysomnographic diagnosis of OSA, non-smoker, absence of comorbidities at diagnosis, and treatment with a MAD. Two polysomnographic monitoring were performed: one at the time of diagnosis (T0) and another after 3 months of treatment (T1). The parameters evaluated were the apnea-hypopnea index, oxygen desaturation index, the total number of position shifts, and position shift index (number of shifts per hour). Since the variables failed the normality test, the Wilcoxon test was performed to analyze the correlation between the mean of polysomnographic parameters at T0 and T1. The difference between the T1 and T0 values for each variable was evaluated using Spearman's rho correlation test. Statistical significance was set at p < 0.05.

Results and conclusions

All the parameters, including respiratory and positional measures, were significantly reduced after the use of a MAD compared to the beginning. Spearman's correlation test revealed a relationship between the total number of sleep position shifts and the sleep position shift index with the oxygen desaturation index. However, no significant correlation was observed between the apnea-hypopnea index and the positional values.

Patients with restless legs syndrome exhibit reduced serum colony-stimulating factor-1, humanin-like 3 and 10 levels

OBJECTIVE

The main pathophysiological mechanisms in restless legs syndrome (RLS) are known as genetic predisposition, brain iron deficiency, and dopaminergic dysfunction. While some genetic variants and polymorphisms were defined, the genetic basis and etiopathogenesis of RLS remain unclear. We aimed to identify new candidate genes and/or potential biomarkers associated with increased RLS risk.

METHODS

Twenty-three patients with RLS, 30 patients with Parkinson's disease (PD), and 27 healthy controls were enrolled. Agilent Human 8X60K Oligo Microarray was used for the identification of gene expression levels in peripheral blood cells. Gene ontology (GO) analysis was used for functional annotation of differentially expressed genes (DEGs). Serum levels of selected DEGs were measured by ELISA for validation.

RESULTS

Patients with RLS showed 30 downregulated DEGs compared to healthy controls. Two genes, MTRNR2L10 and MTRNR2L3, involved negative regulation of the execution phase of apoptosis were highlighted in GO analysis. These genes encode humanin-like 10 and 3, respectively, were encoded by these genes, and their levels, along with CSF-1, linked to neurodegeneration, were reduced in RLS patients. Humanin-like 10 and CSF-1 levels correlated with sleep efficiency and N2 sleep duration, while humanin-like 3 levels correlated with mean sleep oxygen saturation during sleep.

CONCLUSION

Our study showed that several neuroprotective genes were downregulated in RLS, which may confer susceptibility to neuronal death associated with decreased sleep efficiency. Microarray results differed between RLS and PD patients, suggesting diverse pathogenetic mechanisms. CSF-1, which is involved in iron, dopamine metabolism, and blood oxygenation, appears to partake in RLS pathophysiology.

Strange episodes during sleep - epilepsy or parasomnia?

In some forms of epilepsy, the seizures occur almost exclusively during sleep. This is particularly the case with hypermotor frontal lobe seizures. Clinically it can be difficult to distinguish such seizures from parasomnias and psychogenic non-epileptic seizures. This clinical review article aims to highlight the importance of making the correct diagnosis, as these conditions require completely different treatment.