Test-to-test variability in motor activity during the suggested immobilization test in restless legs patients

Validity and reliability of the suggested immobilization test for measurement of restless legs syndrome severity in adults with multiple sclerosis

OBJECTIVE/BACKGROUND

Adults with multiple sclerosis (MS) often present with conditions that mimic restless legs syndrome (RLS), thereby adding complexity into the assessment of RLS severity. The current gold-standard measures of RLS severity rely on a fixed seven-day time frame, which limits the ability of these measures for studying acute changes in RLS severity. The present study examined if subjective and objective scores from the suggested immobilization test (SIT) provide a valid and reliable acute measure of RLS severity in persons with MS.

PATIENTS/METHODS

Participants with MS and RLS (n = 20) and MS without RLS (n = 20) were matched by age, gender, and disability. All participants completed validated questionnaires for RLS severity followed by the SIT, conducted at 18:00 (±15 min) on the same day of the week for two consecutive weeks. Participants wore accelerometer devices for seven nights to capture periodic limb movements (PLMs) during the night.

RESULTS

Self-reported RLS severity during the SIT had excellent construct validity and convergent validity, but moderate test-retest reliability. Device-measured PLMs, while not themselves a direct measure of RLS severity, were significantly associated with PLMs during the night and had excellent test-retest reliability during the SIT in adults with MS.

CONCLUSIONS

Our results suggest that the SIT represents a valid acute measure for capturing self-reported sensory aspects of RLS severity and should be considered in future research and clinical practice as a standardized acute measure of subjective RLS severity in adults with MS who present with RLS.

Which Factors in Spinocerebellar Ataxia Type 3 Patients Are Associated with Restless Legs Syndrome/Willis-Ekbom Disease?

There is evidence of a higher prevalence of restless legs syndrome/Willis-Ekbom disease (RLS/WED) in individuals with spinocerebellar ataxia type 3 (SCA3), although the factors underlying this association remain unknown. The present study aimed to determine the prevalence of RLS/WED in SCA3 patients and to investigate which factors of SCA3 patients are associated with presence of RLS/WED. From February to August of 2006, we carried out clinical interviews in 40 controls and 40 SCA3 patients, diagnosed and followed up at Faculty of Medicine of Ribeirão Preto, University of São Paulo. Twenty-seven SCA3 patients were submitted to a detailed clinical protocol, electroneuromyography, blood work up, polysomnography (PSG), suggested immobilization test (SIT), and magnetic resonance image (MRI). RLS/WED was found in 27.5% of SCA3 patients and 2.5% of normal controls (p = 0.003). The factors related to RLS/WED in SCA3 patients were female gender, age at start of the symptoms of ataxia after 30 years, presence of peripheral neuropathy, and documented iron deficiency. Among SCA3 patients, those with RLS showed higher values of maximal discomfort level and discomfort level sum compared to non-RLS individuals on SIT. There is a relation between RLS/WED and SCA3, which seems to be resultant of different factors whose identification could improve the quality of assistance to those patients as well as to promote a better comprehension of the pathophysiology of both RLS/WED and SCA3.

A method to switch from oral dopamine agonists to rotigotine in patients with restless legs syndrome and mild augmentation

BACKGROUND

We examined the short- and long-term efficacy and tolerability of a cross-titration algorithm from oral dopamine agonists to the rotigotine transdermal patch in patients dissatisfied with their restless legs syndrome (RLS) treatment, predominantly with mild augmentation.

METHODS

Patients with RLS (n = 20) were recruited at a single site. The cross-titration consisted of decreasing oral dopaminergic agents (ropinirole by 1 mg or pramipexole by 0.25 mg) and increasing rotigotine by 1 mg every two days. Efficacy and adverse events (AEs) were assessed at one, three, six and 12 months after the switch.

RESULTS

Patients had moderate-severe RLS symptoms at the baseline (mean international restless legs syndrome (IRLS) score 19.4 ± 5.5); 85% had augmentation and 45% reported afternoon RLS symptoms. The baseline mean pramipexole equivalent dose was 0.6 ± 0.3 mg. At Week 5, 85% (17/20) had successfully switched from their oral dopamine agonist to rotigotine (mean dose 2.5 ± 0.6 mg; change in IRLS score: -6.7 ± 8.4, p = 0.002); 14 patients were CGI-I responders (much or very much improved). Three patients withdrew due to lack of efficacy. Twelve months after cross-titration, 10 patients continued on rotigotine, of whom four required either higher doses of rotigotine or supplemental RLS medication compared with their optimal Week 5 dose; five patients withdrew due to AEs and two due to lack of efficacy.

CONCLUSION

A cross-titration to rotigotine was efficacious after five weeks in 70% of patients dissatisfied with RLS treatment, most of whom had mild augmentation. At one year following the medication switch, 50% had discontinued rotigotine due to lack of continued efficacy or side effects.

Validation of the Multiple Suggested Immobilization Test: A Test for the Assessment of Severity of Restless Legs Syndrome (Willis-Ekbom Disease)

STUDY OBJECTIVES

To validate the Multiple Suggested Immobilization Test (m-SIT), a symptom-provocation test measuring restless legs syndrome (RLS) severity multiple times a day while the patient is awake and resting under controlled conditions. The m-SIT was designed to overcome some limitations in measuring RLS severity with rating scales.

DESIGN

Patients completed two m-SITs on 2 consecutive days while on 24-h dopaminergic medication. After treatment discontinuation, they completed one more m-SIT 3 days later. Controls performed only one m-SIT.

SETTING

Sleep laboratory.

PARTICIPANTS

Nineteen patients with RLS and 10 healthy controls.

INTERVENTIONS

The original m-SIT consisted of seven modified 60-min SITs performed every 2 h between noon and midnight. During each SIT, the subject reclined quietly but could move his or her legs without restriction to alleviate symptoms. Every 10 min, periodic leg movements during wakefulness (PLMW) were evaluated and the m-SIT Disturbance Scale (m-SIT-DS; range 0-10) was completed.

MEASUREMENTS AND RESULTS

The m-SIT, composed of 6:00pm, 8:00pm, 10:00pm, and 12:00pm SITs, discriminated patients from controls (mean m-SIT-DS: 2.68 ± 2.35 versus 0.08 ± 0.26; mean PLMW/h, P = 0.0001) and between treatment groups (on medication versus taken off medication; mean m-SIT-DS, P = 0.0001; mean PLMW/h, P < 0.01). It proved reliable on retest and covariated well with the International Restless Legs Scale (IRLS) and scales measuring daytime symptoms (Spearman ρ > 0.4).

CONCLUSIONS

The m-SIT is a valid and reliable test to evaluate RLS severity and treatment response, and could be useful in the future to confirm diagnosis and identify daytime symptoms. Although it was primarily designed for clinical trials, it might be useful in clinical settings because it provides a standardized testing condition to measure RLS symptoms.

CITATION

Garcia-Borreguero D; Kohnen R; Boothby L; Tzonova D; Larrosa O; Dunkl E. Validation of the Multiple Suggested Immobilization Test: a test for the assessment of severity of restless legs syndrome (Willis-Ekbom disease). SLEEP 2013;36(7):1101-1109.