Search

Objective: To assess emotional processing and alexithymia in patients with restless legs syndrome (RLS) with augmentation versus those who never had augmentation., Methods: We recruited 26 patients who had a history of augmentation (AUG), either current or past, 27 RLS patients treated with dopamine agonists who never had augmentation (RLS controls), and 21 healthy controls (HC). All participants were screened for impulse control disorders (ICDs). Alexithymia was assessed by means of the Toronto Alexithymia Scale - 20 (TAS-20). Facial emotion recognition was tested through an eye-tracking task. Furthermore, all participants performed neuropsychological tests assessing global cognitive status, impulsivity, anxiety, and depression., Results: ICD symptoms occurred more frequently in AUG patients than in RLS controls (P = 0.047). Patients with AUG scored higher on the TAS-20 (P = 0.007) and the attentional subdomain of an impulsivity scale (BIS-11; P = 0.015) compared to HC. Patients with AUG also performed worse on the facial emotion recognition task relative to RLS controls (P = 0.009) and HC (P = 0.003). We found a group difference for the time to first fixation and the fixation count in the mouth region (P = 0.019 and P = 0.021, respectively). There were no other differences in the eye tracking examination., Interpretation: This study showed evidence of poorer emotional processing in patients who had augmentation compared to RLS patients without augmentation and healthy controls. The altered exploration pattern of faces and the higher alexithymia scores suggest abnormalities in emotion processing in patients with augmentation., (© 2020 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)

Meis homeobox 1 (Meis1) is a transcription factor functioning in the development of the nervous system and the cardiovascular system. Both common and rare variants within the gene have been associated with restless legs syndrome (RLS), while its association with symptoms of insomnia has also been discovered recently. RLS is associated with sleep disturbances, and while Meis1 haploinsufficiency is one of the most promising strategies for an RLS animal model, sleep phenotyping of Meis1 knockout mice has never been conducted. We report a detailed sleep analysis of heterozygous Meis1 knockout mice and challenge it with pramipexole, a dopamine agonist used in the treatment of RLS. At baseline, the Meis1-haploinsufficient mice had a trend towards lower delta power in the electroencephalogram (EEG) during sleep compared to the wild-type littermates, possibly indicating reduced sleep quality, but not sleep fragmentation. Pramipexole had a sleep disrupting effect in both genotype groups. In addition, it exerted differential effects on the EEG power spectra of the two mouse lines, remarkably elevating the theta power of the mutant mice during recovery more than that of the wild-types. In conclusion, Meis1 haploinsufficiency seems to have only a modest effect on sleep, but the gene may interact with the sleep-disrupting effect of dopamine agonists., (© 2017 European Sleep Research Society.)

Background and Purpose: Augmentation is a major problem with dopaminergic therapy for restless legs syndrome (RLS), and predictors of augmentation have not yet been identified. We aimed to analyze the relationship between baseline ferritin level and occurrence of augmentation in a retrospective analysis of a prospective double-blind trial of cabergoline versus levodopa on augmentation in RLS., Patients and Methods: Patients who experienced augmentation were compared to patients who did not experience augmentation., Results: Augmentation symptoms causing premature discontinuation from the study or which were tolerated (n=36, ferritin: 85+59 ng/ml) were associated with lower levels of serum ferritin compared to patients without augmentation (n=302, ferritin: 118+108 ng/ml, p=0.0062)., Conclusions: Ferritin as a marker of iron storage may play an important role in the pathophysiology of RLS and may prove to be a biomarker for the development of augmentation under dopaminergic therapy.

Objectives: Augmentation of symptom severity is the main complication of dopaminergic treatment of restless legs syndrome (RLS). The current article reports on the considerations of augmentation that were made during a European Restless Legs Syndrome Study Group (EURLSSG)-sponsored Consensus Conference in April 2006 at the Max Planck Institute (MPI) in Munich, Germany, the conclusions of which were endorsed by the International RLS Study Group (IRLSSG) and the World Association of Sleep Medicine (WASM). The Consensus Conference sought to develop a better understanding of augmentation and generate a better operational definition for its clinical identification., Design and Methods: Current concepts of the pathophysiology, clinical features, and therapy of RLS augmentation were evaluated by subgroups who presented a summary of their findings for general consideration and discussion. Recent data indicating sensitivity and specificity of augmentation features for identification of augmentation were also evaluated. The diagnostic criteria of augmentation developed at the National Institutes of Health (NIH) conference in 2002 were reviewed in light of current data and theoretical understanding of augmentation. The diagnostic value and criteria for each of the accepted features of augmentation were considered by the group. A consensus was then developed for a revised statement of the diagnostic criteria for augmentation., Results: Five major diagnostic features of augmentation were identified: usual time of RLS symptom onset each day, number of body parts with RLS symptoms, latency to symptoms at rest, severity of the symptoms when they occur, and effects of dopaminergic medication on symptoms. The quantitative data available relating the time of RLS onset and the presence of other features indicated optimal augmentation criteria of either a 4-h advance in usual starting time for RLS symptoms or a combination of the occurrence of other features. A paradoxical response to changes in medication dose also indicates augmentation. Clinical significance of augmentation is defined., Conclusion: The Consensus Conference agreed upon new operational criteria for the clinical diagnosis of RLS augmentation: the MPI diagnostic criteria for augmentation. Areas needing further consideration for validating these criteria and for understanding the underlying biology of RLS augmentation are indicated.