Consistent skin α-synuclein positivity in REM sleep behavior disorder - A two center two-to-four-year follow-up study

OBJECTIVE/METHODS

Phosphorylated alpha-synuclein (p-syn) in dermal nerves of patients with isolated REM sleep behavior disorder (iRBD) is detectable by immunofluorescence-labeling. Skin-biopsy-p-syn-positivity was recently postulated to be a prodromal marker of Parkinson's disease (PD) or related synucleinopathies. Here, we provide two-to four-year clinical and skin biopsy follow-up data of 33 iRBD patients, whose skin biopsy findings at baseline were reported in 2017.

RESULTS

Follow-up biopsies were available from 25 patients (18 positive at baseline) and showed consistent findings over time in 24 patients. One patient converted from skin-biopsy-negativity to -positivity. P-syn-positivity was observed in iRBD patients who still had a normal FP-CIT-SPECT two years later. Clinically, five of the 23 at baseline skin-biopsy-positive patients (21.7%) had converted to PD or dementia with Lewy bodies at follow-up, but none of the skin-biopsy-negative patients.

CONCLUSIONS

Dermal p-syn in iRBD is most probably an early consistent marker of synucleinopathy and may support other indicators of conversion to manifest disease state.

0525 Subtypes of Efficacy of Cognitive-Behavioral Therapy for Insomnia

Introduction

Cognitive-Behavioral Therapy for Insomnia (CBT-I) is the first-line treatment for Insomnia disorder (ID). We aimed to identify ID patients’ subtypes based on clinical features and their response to CBT-I.

Methods

294 chronic insomnia patients (61.6% female, mean age 40.7 ± 12.3 yrs) underwent 7-sessions group CBT-I. By use of latent class analysis (LCA) we identified insomnia disorder subtypes according to baseline (BL) evaluation of non-sleep indices and the response to CBT-I (Delta score of Insomnia Severity Index ISI between BL and end-of-treatment (ET). Moreover, we assessed ISI in 123 out of 294 insomnia patients (82 females (66.7%), mean age 40.59 ± 11.89 years) who completed a follow-up evaluation (FU) within a range of 4-10 years.

Results

We chose 3 latent classes as most parsimonious model. We identified Class 1 (insomnia+anxiety+depression+stress) (n=62), Class 2 (insomnia+anxiety+depression) (n=153) and Class 3 (only-insomnia) (n=79). The effect of CBT-I was maintained up to 10 years after the ET in the three classes but with significant difference between classes (p<0.05). At the ET, the largest percentage of responders (ISI decrease ≥ 8) was found in Class 1 (63.5%). Results of overall CBT-I effectiveness: in Class 3, 98.6% had subthreshold insomnia (ISI score=0-14) at the ET, and 97.2% at the FU; in Class 2, 89.0% at the ET, and 78.2% at the FU; in Class 1, 80.7% at ET and 51.8% at the FU.

Conclusion

Our analysis identified three different subtypes of insomniacs on the basis of clinical outcomes. The presence of anxiety and depression did not diminish the effect of CBT-I both short and long term. However, ID patients characterized by the presence of stress (Class 1) were the best responders at the ET but this was not maintained at the FU evaluation. We can speculate that stress could be considered a risk factor that plays an important role in the long-term outcome of CBT-I.

Support

No

0522 Subtypes of Insomniacs Treated by Cognitive-Behavioral Therapy

Introduction

Insomnia disorder (ID) is characterized by high degree of heterogeneity. Aim of our study was to identify ID patients subtypes in terms of sleep and non-sleep clinical baseline (BL) features and CBT-I efficacy.

Methods

294 chronic insomnia patients (61.6% female, mean age 40.7 ± 12.3 yrs) underwent 7-sessions group CBT-I. By use of latent class analysis (LCA) we identified ID subtypes according to BL score of Glasgow Sleep Effort Scale (GSES); Epworth Sleepiness Scale (ESS); Dysfunctional Beliefs and Attitudes about Sleep (DBAS -16); Morningness-Eveningness Questionnaire Self-Assessment (MEQ-SA); Perceived Stress Scale (PSS); Profile of Mood States (POMS); Beck Depression Inventory (BDI-II); Stay-Trait Anxiety Inventory (STAI-Y); Treatment effectiveness (Delta score of Insomnia Severity Index ISI between BL and end-of-treatment).

Results

We chose 3 latent classes as most parsimonious model. According to questionnaires’ cut-off, we labeled three classes: Class 1 (insomnia+anxiety+depression+stress) (n=62), Class 2 (insomnia+anxiety+depression) (n=153), Class 3 (only insomnia) (n=79). The variables that best differentiate the 3 classes were POMS (.772), STAY (.660), PSS (.545), BDI (.406) and ISI (.228) at BL. In particular, for ISI, the best item predicting groups differentiation was item 3 on the impact of insomnia on daytime functioning (.224). Moreover, we found a significant interaction between CBT-I treatment effect and the 3 classes at the ISI score (p=.001), GSES score (p=.002), DBAS score (p<.05), PSS score (p<.001), POMS score (p<.001), BDI score (p<.001) and STAI-Y score (p<.001).

Conclusion

Our data driven analysis results suggest that the heterogeneity of ID patients can be best represented by non-sleep scores, in particular those regarding depression, anxiety, stress and daytime functioning. These information can be useful in predicting the outcome of CBT-I.

Support

No

Red Flags for early referral of people with symptoms suggestive of narcolepsy: a report from a national multidisciplinary panel

OBJECTIVE

Narcolepsy is a lifelong disease, manifesting with excessive daytime sleepiness and cataplexy, arising between childhood and young adulthood. The diagnosis is typically made after a long delay that burdens the disease severity. The aim of the project, promoted by the "Associazione Italiana Narcolettici e Ipersonni" is to develop Red Flags to detect symptoms for early referral, targeting non-sleep medicine specialists, general practitioners, and pediatricians.

MATERIALS AND METHODS

A multidisciplinary panel, including patients, public institutions, and representatives of national scientific societies of specialties possibly involved in the diagnostic process of suspected narcolepsy, was convened. The project was accomplished in three phases. Phase 1: Sleep experts shaped clinical pictures of narcolepsy in pediatric and adult patients. On the basis of these pictures, Red Flags were drafted. Phase 2: Representatives of the scientific societies and patients filled in a form to identify barriers to the diagnosis of narcolepsy. Phase 3: The panel produced suggestions for the implementation of Red Flags.

RESULTS

Red Flags were produced representing three clinical pictures of narcolepsy in pediatric patients ((1) usual sleep symptoms, (2) unusual sleep symptoms, (3) endocrinological signs) and two in adult patients ((1) usual sleep symptoms, (2) unusual sleep symptoms). Inadequate knowledge of symptoms at onset by medical doctors turned out to be the main reported barrier to diagnosis.

CONCLUSIONS

This report will hopefully enhance knowledge and awareness of narcolepsy among non-specialists in sleep medicine in order to reduce the diagnostic delay that burdens patients in Italy. Similar initiatives could be promoted across Europe.

Preliminary evidence that vortioxetine may improve sleep quality in depressed patients with insomnia: a retrospective questionnaire analysis

Insomnia is a frequent symptom in depressed patients. It can present with difficulty in initiating and/or maintaining sleep. We retrospectively evaluated a group of 15 patients affected by major depressive disorder and complaining of insomnia, who started vortioxetine (VOR) treatment for their depressive symptoms. The following questionnaires were captured at baseline and follow-up: Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale and Beck Depression Inventory. Pittsburgh Sleep Quality Index total score significantly decreased between follow-up and baseline (P < 0.01), and in several subitems related to sleep quality and continuity. Moreover, Epworth Sleepiness Scale decreased between follow-up and baseline (P < 0.01). Finally, Beck Depression Inventory reduction was also evident between follow-up and baseline (P < 0.01). This retrospective analysis showing the significant effect of VOR on both depressive symptoms and insomnia in patients showing comorbid major depressive disorder and insomnia invites further research in order to confirm this preliminary evidence. We hypothesize that the VOR mechanism of action may explain the improvement of subjective sleep, other than depressive symptoms.

Long-term Correlations and Complexity Analysis of the Heart Rate Variability Signal during Sleep

Background: Physiological sleep is characterized by different cyclic phenomena, such as REM, nonREM phases and the Cyclic Alternating Pattern (CAP), that are associated to characteristic patterns in the heart rate variability (HRV) signal. Disruption of such rhythms due to sleep disorders, for example insomnia or apnea syndrome, alters the normal sleep patterns and the dynamics of the HRV recorded during the night.

Objectives: In this paper we analyze long-term and complexity dynamics of the HRV signal recorded during sleep in different groups of subjects. The aim is to investigate whether the calculated indices are able to capture the different characteris tics and to discriminate among the groups of subjects, classified according sleep disorders or cardiovascular pathologies.

Methods: Parameters, able to detect the fractal-like behavior of a signal and to measure the regularity and complexity of a time series, are calculated on the HRV signal acquired during the night. Different groups of subjects were analyzed: healthy subjects with high sleep efficiency, healthy subjects with low sleep efficiency, subjects affected by insomnia, heart failure patients, subjects affected by obstructive sleep apnea.

Results: The evaluated parameters show significant differences in the groups of subjects considered in this work. In particular heart failure patients have significant lower entropy and complexity values, whereas apnea patients show an increased irregularity when compared with normal subjects with high sleep efficiency.

Conclusions: This work proposes indices that can be used as global descriptors of the dynamics of the whole night and can discriminate among different groups of subjects.

Chronic Daily Headache in Childhood and Adolescence: Clinical Aspects and a 4-Year Follow-up

Chronic daily headache (CDH) represents a challenge in clinical practice and the scientific field. CDH with onset in children and adolescents represent a matchless opportunity to understand mechanisms involved in adult CDH. The aim of this study was to evaluate the diagnosis, prognosis and psychiatric co-morbidity of CDH with young onset in the young. Fifty-nine CDH patients has been followed from 1997 to 2001 in our department. Headache and psychiatric diagnoses were made on the basis of the international system of classification (International Headache Society, 1988; DSM-IV). X2 test and multinomial logistic regressions were applied to analyse factors predicting outcome. The current diagnostic system allows a diagnosis in 80% of CDH patients, even if age-related characteristics have been evidenced. Psychiatric disorders are notable in CDH (about 64% of patients) and predict (mainly anxiety) a poorer outcome. Surprisingly, analgesic overuse is not involved in the chronicization process. Diagnosis of CDH needs further study. Psychiatric disorders predict a worse outcome and greater account should be taken of them in treatment planning.

On the pathway of an animal model for restless legs syndrome

Restless legs syndrome (RLS) is a chronic sleep motor disorder that affects up to 10% of the general population. Except for periodic leg movements (PLM), which can be found in the great majority of RLS patients, no objective hematochimic or neurophysiological markers are available to prove the diagnosis, which is based on clinical standard criteria. Nowadays, the aetiopathogenesis of the syndrome is unknown. In a consistent sample of patients affected by the idiopathic form, the disease is inherited as an autosomal dominant trait related to an unidentified locus, while each symptomatic form is probably linked to a specific cause. Although of possible different origins, both the primary and secondary forms may share the same pathogenetic mechanism, which, even if unclear, could be characterised by a neurological dysfunction of the dopaminergic system. Several issues, including strong efficacy of dopamine-agonist treatments, support this theory, which is currently considered the main pathogenetic hypothesis. Most of the past studies tried to clarify the RLS mechanism using the neurophysiological, biochemical and neuroimaging techniques applied to the field of human research. Now the time has come to accept the challenge in creating an animal model of RLS, which may emerge as a decisive step in understanding RLS pathogenesis, and to develop and test new therapies. Even though there have been a few significant efforts, a valid animal model of RLS still does not exist. In past pioneering studies, the authors attempted to induce restless motor behaviour in animals by different strategies: antidopaminergic pharmacological interventions, spinal or cerebral lesions of specific regions involved in the motor control and in dopamine regulation, and selective deletion of genes coding for dopamine receptors. Rodents (mice and rats) were always chosen by the authors as the animals for their experiments. The current tendency in achieving an RLS model is generally represented by simulation of a symptomatic condition of RLS or by a direct interference of the dopaminergic system. In this regard, the pharmacological method had the intention to reproduce the neuroleptic-induced acathisia, the spinal lesional model was based on the hypothesis of myelopathic- related PLM, and the hypothalamic lesion tested the motor consequence of A11 dopaminergic neurons. Preliminary studies are underway to replicate the pregnancy-related form of RLS by using a hormonal intervention, and the iron-deficiency secondary form by using specific iron-free diets. Today, modern technologies are available to easily replicate in animals most of the symptomatic RLS conditions. In addition, more than a few well validated animal models of different diseases known to be related to RLS or PLM, for instance, Parkinson's disease, rheumatoid arthritis and renal failure, could also be exploited in addressing this topic. The real obstacle in achieving an RLS model is the absence of a certain diagnostic marker to recognise if the animal that underwent the different experimental procedures has developed the RLS condition or not. Concerning this issue, possible specific endpoints are represented by the increase in locomotor activity, which are ascertainable by different techniques, such as openfield or run-wheel activity, or by sleep fragmentation, in which the circadian shift can be verified by applying polysomnography on the animal. PLM are probably the only specific and reliable markers available to recognise and quantify experimentally induced RLS. Despite a few authors who reported the presence of limb-phasic, pseudoperiodic activity during sleep in old or in lesioned rats, the existence of spontaneous or provoked PLM in animals is still debated. Eventually, the PLM features in an animal could be markedly different compared to human ones. To recognise and characterise PLM in animals, three more essential steps are required: a method to record directly, as in humans, the activity of the tibialis anterior (TA) muscles, a consistent amount of normative control data on the TA activity in healthy animals, and reliable analysis to distinguish the generic phasic muscular activity to a possible unambiguous PLM pattern. This review includes a summary and a critical discussion of the previous tentative RLS models, proposals for other possible animal models, and firstly the preliminary normative data on TA activity during sleep in normal rodents.

REM Sleep Behavior Disorder (RBD) as a marker of neurodegenerative disorders

Rapid eye movement (REM) sleep behavior disorder (RBD) can occur in the absence of any other obvious associated neurologic disorder or in association with a neurodegenerative disease, in which case it is considered as symptomatic RBD. RBD is frequently associated with Parkinson's disease (PD), Lewy body dementia or multiple system atrophy (MSA), and in several cases may even antedate the occurrence of motor symptoms by decades. When no neurologic disorder is obvious, RBD can be considered as idiopathic (iRBD). Several studies have looked at neurophysiologic and neuropsychological functions in iRBD and have found evidence of CNS dysfunction during both wakefulness and sleep in a variable proportion of these patients, challenging the concept of iRBD. Identifying subjects with a high risk of developing a neurodegenerative process may be crucial in order to develop early intervention strategies. Some prospective results in iRBD showed that potential markers of neurodegeneration are the following: 1) marked EEG slowing on spectral analysis; 2) decreased striatal 123I-FPCIT; 3) impaired color vision.

Rapid eye movement sleep behavior disorder: devising controlled active treatment studies for symptomatic and neuroprotective therapy--a consensus statement from the International Rapid Eye Movement Sleep Behavior Disorder Study Group

OBJECTIVES

We aimed to provide a consensus statement by the International Rapid Eye Movement Sleep Behavior Disorder Study Group (IRBD-SG) on devising controlled active treatment studies in rapid eye movement sleep behavior disorder (RBD) and devising studies of neuroprotection against Parkinson disease (PD) and related neurodegeneration in RBD.

METHODS

The consensus statement was generated during the fourth IRBD-SG symposium in Marburg, Germany in 2011. The IRBD-SG identified essential methodologic components for a randomized trial in RBD, including potential screening and diagnostic criteria, inclusion and exclusion criteria, primary and secondary outcomes for symptomatic therapy trials (particularly for melatonin and clonazepam), and potential primary and secondary outcomes for eventual trials with disease-modifying and neuroprotective agents. The latter trials are considered urgent, given the high conversion rate from idiopathic RBD (iRBD) to Parkinsonian disorders (i.e., PD, dementia with Lewy bodies [DLB], multiple system atrophy [MSA]).

RESULTS

Six inclusion criteria were identified for symptomatic therapy and neuroprotective trials: (1) diagnosis of RBD needs to satisfy the International Classification of Sleep Disorders, second edition, (ICSD-2) criteria; (2) minimum frequency of RBD episodes should preferably be ⩾2 times weekly to allow for assessment of change; (3) if the PD-RBD target population is included, it should be in the early stages of PD defined as Hoehn and Yahr stages 1-3 in Off (untreated); (4) iRBD patients with soft neurologic dysfunction and with operational criteria established by the consensus of study investigators; (5) patients with mild cognitive impairment (MCI); and (6) optimally treated comorbid OSA. Twenty-four exclusion criteria were identified. The primary outcome measure for RBD treatment trials was determined to be the Clinical Global Impression (CGI) efficacy index, consisting of a four-point scale with a four-point side-effect scale. Assessment of video-polysomnographic (vPSG) changes holds promise but is costly and needs further elaboration. Secondary outcome measures include sleep diaries; sleepiness scales; PD sleep scale 2 (PDSS-2); serial motor examinations; cognitive indices; mood and anxiety indices; assessment of frequency of falls, gait impairment, and apathy; fatigue severity scale; and actigraphy and customized bed alarm systems. Consensus also was established for evaluating the clinical and vPSG aspects of RBD. End points for neuroprotective trials in RBD, taking lessons from research in PD, should be focused on the ultimate goal of determining the performance of disease-modifying agents. To date no compound with convincing evidence of disease-modifying or neuroprotective efficacy has been identified in PD. Nevertheless, iRBD patients are considered ideal candidates for neuroprotective studies.

CONCLUSIONS

The IRBD-SG provides an important platform for developing multinational collaborative studies on RBD such as on environmental risk factors for iRBD, as recently reported in a peer-reviewed journal article, and on controlled active treatment studies for symptomatic and neuroprotective therapy that emerged during the 2011 consensus conference in Marburg, Germany, as described in our report.

Environmental risk factors for REM sleep behavior disorder: a multicenter case-control study

OBJECTIVE

Idiopathic REM sleep behavior disorder is a parasomnia characterized by dream enactment and is commonly a prediagnostic sign of parkinsonism and dementia. Since risk factors have not been defined, we initiated a multicenter case-control study to assess environmental and lifestyle risk factors for REM sleep behavior disorder.

METHODS

Cases were patients with idiopathic REM sleep behavior disorder who were free of dementia and parkinsonism, recruited from 13 International REM Sleep Behavior Disorder Study Group centers. Controls were matched according to age and sex. Potential environmental and lifestyle risk factors were assessed via standardized questionnaire. Unconditional logistic regression adjusting for age, sex, and center was conducted to investigate the environmental factors.

RESULTS

A total of 694 participants (347 patients, 347 controls) were recruited. Among cases, mean age was 67.7 ± 9.6 years and 81.0% were male. Cases were more likely to smoke (ever smokers = 64.0% vs 55.5%, adjusted odds ratio [OR] = 1.43, p = 0.028). Caffeine and alcohol use were not different between cases and controls. Cases were more likely to report previous head injury (19.3% vs 12.7%, OR = 1.59, p = 0.037). Cases had fewer years of formal schooling (11.1 ± 4.4 years vs 12.7 ± 4.3, p < 0.001), and were more likely to report having worked as farmers (19.7% vs 12.5% OR = 1.67, p = 0.022) with borderline increase in welding (17.8% vs 12.1%, OR = 1.53, p = 0.063). Previous occupational pesticide exposure was more prevalent in cases than controls (11.8% vs 6.1%, OR = 2.16, p = 0.008).

CONCLUSIONS

Smoking, head injury, pesticide exposure, and farming are potential risk factors for idiopathic REM sleep behavior disorder.

Bruxism and nocturnal groaning

Sleep bruxism (SB) is a sleep-related movement disorder, characterized by tooth grinding and/or clenching. The causes of SB range from psychosocial factors to an excessive sleep arousal response. Some studies showed that SB episodes during sleep are under the influences of transient activity of the brainstem arousal. Nocturnal groaning (NG) is a parasomnia characterized by an expiratory monotonous vocalization occurring during sleep, especially in REM sleep and during the second half of the night. The pathogenesis of NG remains still unclear and many hypotheses arose, ranging from the persistence of a vestigial ventilatory pattern rather than an expiratory upper airways' obstruction. Sleep microstructure fluctuation might modulate the NG, since the end of the NG episode usually is synchronized with a cortical arousal and an autonomic activation. Further studies should clarify the pathophysiology of SB and NG, especially when the two phenomena are associated.

Sleep disordered breathing in renal transplant patients

Sleep disordered breathing (SDB) is a prevalent, important nontraditional cardiovascular (CV) risk factor in end-stage renal disease patients. The prevalence of SDB in renal transplant patients is unknown. We compared polysomnographic studies in 163 transplant patients with matched samples in the general population and explored longitudinally the effect of return to dialysis after graft failure on SDB in three consecutive cases. Episodes of nocturnal hypoxemia, average and minimal O(2) saturation overnight in transplant patients did not differ from those in individuals in the general population matched for age, gender and body mass index (BMI). The prevalence of moderate-to-severe SBD in these patients did not exceed the estimated prevalence of the same disturbance in the general population. The respiratory disturbance index in transplant patients was directly associated with BMI (p < 0.001). In the longitudinal study all indicators of SDB coherently increased after transplant failure. The prevalence of SDB in transplant patients does not differ from that in well-matched individuals in the general population. The favorable effect of renal transplantation on CV risk may be at least partially explained by the lack of risk excess for SDB in this population. Longitudinal observations after transplant failure are compatible with the hypothesis that renal transplantation reverses SDB.

Periodic leg movements in Cheyne-Stokes respiration

Periodic leg movements during sleep (PLMS) are repetitive jerks of the lower limbs. Their occurrence can be isolated or part of various sleep disorders, such as restless legs syndrome (RLS), narcolepsy and obstructive sleep apnoea. Dopamine agonists are very effective in suppressing PLMS in RLS from the first night of administration. PLMS are often associated with cortical and autonomic arousals and may contribute to sleep disruption. Herein, a case of association between PLMS, Cheyne-Stokes respiration (CSR) and severe insomnia is described. Repeated polysomnographic studies demonstrated a clear synchronisation between PLMS and hyperventilation episodes, and the complete recovery of CSR, sleep quality and PLMS during nocturnal ventilation. In the same patient, pharmacological treatment with a dopamine agonist was ineffective on both PLMS and CSR. These results suggest that periodic leg movements during sleep coupled with central breathing events, similar to those observed in conjunction with obstructive events, may have a different origin in terms of neurotransmitter and pathway implicated, compared with periodic leg movements during sleep in restless legs syndrome, and are resolved by treatment of the respiratory abnormalities.

Restless legs syndrome is a common finding in multiple sclerosis and correlates with cervical cord damage

In this prospective study, we estimated the prevalence of restless legs syndrome (RLS) in multiple sclerosis (MS) patients, and compared the extent of brain and cervical cord damage between patients with and without RLS using conventional and diffusion tensor magnetic resonance imaging (MRI). Eighty-two consecutive MS patients were evaluated. Each patient underwent a medical history interview, a neurological examination and brain/cervical cord MRI. Global and regional dual-echo lesion load (LL), number of cervical cord lesions, mean diffusivity (MD) and fractional anisotropy (FA) histograms metrics of the normal-appearing tissues of the brain and cervical cord were assessed. Thirty subjects had RLS; they showed a higher Expanded Disability Status Scale score than patients without. No difference between the two groups was found in whole brain, cerebellar and brainstem T(2)-LLs; MD and FA histograms derived metrics of the normal appearing brain tissues; basal ganglia MD; number of cervical cord lesions and cord MD histograms derived metrics. Cervical cord average FA was significantly reduced in MS patients with RLS compared to those without. RLS symptoms are very common in MS. This form of RLS should be considered as symptomatic. Higher disability and cervical cord damage represent a significant risk factor for RLS in MS patients.

High prevalence of restless legs syndrome in multiple sclerosis

Despite the fact that multiple sclerosis (MS) patients often include leg restlessness as a sensory symptom, MS is not mentioned amongst symptomatic restless legs syndrome (RLS) forms. The aim of this study was to estimate RLS prevalence in a large population of MS patients, comparing clinical and MRI findings between patients with and without RLS. Each of the 156 MS patients (100 females, 56 males, mean age 40.7 +/- 10.4) enrolled in a prospective study underwent a medical history interview, a neurological examination with the assessment of the Expanded Disability Status Scale (EDSS), and a structured questionnaire to verify the presence and features of RLS. Conventional brain-spinal MRIs of 99 subjects were also evaluated and compared between patients with and without RLS. Fifty-one subjects (32.7%) (mean age 43.8 +/- 12.8) met the criteria for RLS. In a few patients (8.5%), the RLS preceded clinical MS onset, whilst in the remaining cases the RLS was followed by or was simultaneous with clinical MS onset. Comparing the RLS group with the group without RLS, no significant differences were found in MS duration, gender, and referred sleep habits. The primary progressive MS course was more represented in the RLS group, which also showed a higher EDSS score. RLS is a very common finding in MS patients and should be considered amongst the symptomatic RLS forms. RLS is also associated with higher disability.