Psychological distress of patients suffering from restless legs syndrome: a cross-sectional study

<p>Abstract</p> <p>Background</p> <p>Restless legs syndrome (RLS) is a chronic disorder with substantial impact on quality of life similar to that seen in diabetes mellitus or osteoarthritis. Little is known about the psychological characteristics of RLS patients although psychological factors may contribute to unfavourable treatment outcome.</p> <p>Methods</p> <p>In an observational cross-sectional design, we evaluated the psychological features of 166 consecutive RLS patients from three outpatient clinics, by means of the Symptom Checklist 90-R (SCL-90-R) questionnaire. Additionally, the Beck Depression Inventory-II (BDI-II) and the International RLS Severity Scale (IRLS) were measured. Both treated and untreated patients were included, all patients sought treatment.</p> <p>Results</p> <p>Untreated patients (n = 69) had elevated but normal scores on the SCL-90-R Global Severity Index (GSI; p = 0.002) and on the sub-scales somatisation (p < 0.001), compulsivity (p = 0.003), depression (p = 0.02), and anxiety (p = 0.004) compared with a German representative sample. In the treated group, particularly in those patients who were dissatisfied with their actual treatment (n = 62), psychological distress was higher than in the untreated group with elevated scores for the GSI (p = 0.03) and the sub-scales compulsivity (p = 0.006), depression (p = 0.012), anxiety (p = 0.031), hostility (p = 0.013), phobic anxiety (p = 0.024), and paranoid ideation (p = 0.012). Augmentation, the most serious side effect of dopaminergic, i.e. first-line treatment of RLS, and loss of efficacy were accompanied with the highest psychological distress, as seen particularly in the normative values of the sub-scales compulsivity and anxiety. Generally, higher RLS severity was correlated with higher psychological impairment (p < 0.001).</p> <p>Conclusion</p> <p>Severely affected RLS patients show psychological impairment in multiple psychological domains which has to be taken into account in the treatment regimen.</p

Progressive development of augmentation during long-term treatment with levodopa in restless legs syndrome: results of a prospective multi-center study

The European Restless Legs Syndrome (RLS) Study Group performed the first multi-center, long-term study systematically evaluating RLS augmentation under levodopa treatment. This prospective, open-label 6-month study was conducted in six European countries and included 65 patients (85% treatment naive) with idiopathic RLS. Levodopa was flexibly up-titrated to a maximum dose of 600 mg/day. Presence of augmentation was diagnosed independently by two international experts using established criteria. In addition to the augmentation severity rating scale (ASRS), changes in RLS severity (International RLS severity rating scale (IRLS), clinical global impression (CGI)) were analyzed. Sixty patients provided evaluable data, 35 completed the trial and 25 dropped out. Augmentation occurred in 60% (36/60) of patients, causing 11.7% (7/60) to drop out. Median time to occurrence of augmentation was 71 days. The mean maximum dose of levodopa was 311 mg/day (SD: 105). Patients with augmentation compared to those without were significantly more likely to be on higher doses of levodopa (≥300 mg, 83 vs. 54%, P = 0.03) and to show less improvement of symptom severity (IRLS, P = 0.039). Augmentation was common with levodopa, but could be tolerated by most patients during this 6-month trial. Patients should be followed over longer periods to determine if dropout rates increase with time

Cerebral correlates of muscle tone fluctuations in restless legs syndrome: A pilot study with combined functional magnetic resonance imaging and anterior tibial muscle electromyography

BACKGROUND: The pathology of restless legs syndrome (RLS) is still not understood. To investigate the pathomechanism of the disorder further we recorded a surface electromyogram (EMG) of the anterior tibial muscle during functional magnetic resonance imaging (fMRI) in patients with idiopathic RLS. METHODS: Seven subjects with moderate to severe RLS were investigated in the present pilot study. Patients were lying supine in the scanner for over 50min and were instructed not to move voluntarily. Sensory leg discomfort (SLD) was evaluated on a 10-point Likert scale. For brain image analysis, an algorithm for the calculation of tonic EMG values was developed. RESULTS: We found a negative correlation of tonic EMG and SLD (p <0.01). This finding provides evidence for the clinical experience that RLS-related subjective leg discomfort increases during muscle relaxation at rest. In the fMRI analysis, the tonic EMG was associated with activation in motor and somatosensory pathways and also in some regions that are not primarily related to motor or somatosensory functions. CONCLUSIONS: By using a newly developed algorithm for the investigation of muscle tone-related changes in cerebral activity, we identified structures that are potentially involved in RLS pathology. Our method, with some modification, may also be suitable for the investigation of phasic muscle activity that occurs during periodic leg movements

Identification of Restless Legs Syndrome Genes by Mutational Load Analysis

Objective Restless legs syndrome is a frequent neurological disorder with substantial burden on individual well-being and public health. Genetic risk loci have been identified, but the causatives genes at these loci are largely unknown, so that functional investigation and clinical translation of molecular research data are still inhibited. To identify putatively causative genes, we searched for highly significant mutational burden in candidate genes. Methods We analyzed 84 candidate genes in 4,649 patients and 4,982 controls by next generation sequencing using molecular inversion probes that targeted mainly coding regions. The burden of low-frequency and rare variants was assessed, and in addition, an algorithm (binomial performance deviation analysis) was established to estimate independently the sequence variation in the probe binding regions from the variation in sequencing depth. Results Highly significant results (considering the number of genes in the genome) of the conventional burden test and the binomial performance deviation analysis overlapped significantly. Fourteen genes were highly significant by one method and confirmed with Bonferroni-corrected significance by the other to show a differential burden of low-frequency and rare variants in restless legs syndrome. Nine of them (AAGAB, ATP2C1, CNTN4, COL6A6, CRBN, GLO1, NTNG1, STEAP4, VAV3) resided in the vicinity of known restless legs syndrome loci, whereas 5 (BBS7, CADM1, CREB5, NRG3, SUN1) have not previously been associated with restless legs syndrome. Burden test and binomial performance deviation analysis also converged significantly in fine-mapping potentially causative domains within these genes. Interpretation Differential burden with intragenic low-frequency variants reveals putatively causative genes in restless legs syndrome. ANN NEUROL 201