A dose-ranging study of pramipexole for the symptomatic treatment of restless legs syndrome: Polysomnographic evaluation of periodic leg movements and sleep disturbance

Objective: To evaluate, both polysomnographically and by subjective scales, the efficacy and safety profile of pramipexole for restless legs syndrome (RLS) via a 3-week, double-blind, placebo-controlled, parallel-group, dose-ranging study.Methods: At baseline and after 3 weeks, periodic limb movements (PLM) and sleep parameters were assessed by polysomnography, and patients self-assessed their sleep disturbance and overall RLS severity using the international RLS study group rating scale (IRLS). Four pramipexole doses were evaluated: 0.125, 0.25, 0.50, and 0.75 mg/d. Data from 107 patients were included in the intent-to-treat (ITT) analysis.Results: For pramipexole recipients, the primary outcome measure, PLM per hour in bed asleep or awake (the PLM index, or PLMI), decreased by a median of ?26.55 to ?52.70 depending on dosage group, vs. ?3.00 for placebo (p < 0.01 or ?0.001 for each group vs. placebo; Wilcoxon–Mann–Whitney test). Improvements in the secondary endpoints of PLM while asleep and while awake were also significantly superior for pramipexole. At 3 weeks, all pramipexole doses reduced the median for PLM while asleep to levels considered normal (<5 PLM/h). Except for delta-sleep time and awakenings/arousals, sleep parameters remained unchanged or favored pramipexole. Median sleep latency was reduced by ?5.00 to ?11.75 min in the pramipexole groups, vs. ?2.00 for placebo (p < 0.05 for all groups except 0.25 mg/d). Median total sleep time increased by 25.75–66.75 min, vs. 25.50 (p < 0.05 for 0.50 mg/d), and median time in stages 2–4/rapid eye movement (REM) sleep increased by 37.00–68.00 min, vs. 26.75 (p < 0.05 for 0.50 mg/d). By subjective IRLS ratings, all pramipexole doses were significantly superior to placebo. Safety analysis demonstrated no dose-dependent increase in adverse events, and no drug-related increase in daytime somnolence was observed.Conclusions: Pramipexole is effective and well tolerated in RLS, most notably among objective measures, for reducing PLM and decreasing sleep latency. Although other sleep parameters showed lesser, usually insignificant change, patients’ subjective ratings of RLS severity and sleep disturbance were significantly improved (p ? 0.0023).     

Effect of pramipexole on RLS symptoms and sleep: a randomized, double-blind, placebo-controlled trial

BackgroundPatients with Restless Legs Syndrome (RLS) often seek treatment because of sleep problems related to nocturnal symptoms. Our goal was to test the ability of pramipexole to improve sleep in RLS patients and to reconfirm its efficacy for primary RLS symptoms.MethodsAdults with moderate or severe RLS were randomized to receive placebo or pramipexole (flexibly titrated from 0.25 to 0.75 mg), 2–3 h before bedtime for 12 weeks. The co-primary outcome measures were change in Medical Outcomes Study (MOS) sleep disturbance score and International RLS Study Group Rating Scale (IRLS) score at 12 weeks.ResultsThe intent-to-treat population included 357 patients: 178 received pramipexole and 179 received placebo. At 12 weeks, the adjusted mean change from baseline was greater for pramipexole (vs. placebo) for IRLS score (−13.4 ± 0.7 vs. −9.6 ± 0.7) and MOS sleep disturbance score (−25.3 ± 1.5 vs. −16.8 ± 1.5) (p ⩽ 0.0001; ANCOVA). Responder rates (clinical and patient global impression and IRLS) were also significantly higher in the pramipexole group. RLS-QOL score was improved over placebo at Week 12 (p < 0.01) as were MOS sleep adequacy (p = 0.0008) and quantity (p = 0.08) scores. Nine percent of patients in each group withdrew because of adverse events.ConclusionsPramipexole is effective and well-tolerated for RLS and related sleep disturbance.     

Rotigotine transdermal patch in moderate to severe idiopathic restless legs syndrome: A randomized,placebo-controlled polysomnographic study

ObjectiveTo assess the efficacy of rotigotine transdermal patch in subjects with moderate to severe idiopathic restless legs syndrome (RLS) and periodic limb movement (PLM) in sleep in a double-blind, randomized, placebo-controlled, multicenter study (NCT00275236).MethodsSixty-seven (46 rotigotine, 21 placebo) subjects applied rotigotine (maximum 3 mg/24 h) or placebo patches once-daily during a 4-week maintenance period; efficacy evaluations used polysomnographic measures and clinician/patient ratings.ResultsMean PLM index (PLMI; PLM/h time in bed) decreased more with rotigotine (50.9/h to 8.1/h) than with placebo (37.4/h to 27.1/h; adjusted treatment ratio 4.25 (95% CI [2.48, 7.28], p < 0.0001). PLM during sleep with arousal index (PLMSAI; 8.57/h to 2.47/h under rotigotine, 6.5/h to 4.95/h under placebo; adjusted treatment difference: ?3.12 (95% CI [?5.36, ?0.88], p = 0.0072) also improved more under rotigotine. At end of maintenance, 39% of rotigotine subjects had PLMI levels <5/h and 26% showed no RLS symptoms (IRLS = 0), whereas no placebo subject met these criteria. Common drug-related adverse events for rotigotine and placebo included nausea (21.7%/4.8%), headache (17.4%/14.3%), application site reactions (17.4%/4.8%), and somnolence (10.9%/9.5%); most were mild to moderate in intensity.ConclusionsRotigotine transdermal patch was efficacious and well tolerated in the short-term treatment of RLS motor symptoms and associated sleep disturbances.     

Restless legs syndrome in end-stage renal disease: Clinical characteristics and associated comorbidities

BackgroundDespite being frequently described in patients with end-stage renal disease (ESRD), clinical characteristics and comorbidities in association with restless legs syndrome (RLS) are still to be confirmed.ObjectivesThe aim of this study was to investigate clinical factors associated with RLS in ESRD patients in hemodialysis.MethodsThis is a cross-sectional study of 400 patients on hemodialysis, evaluating RLS, clinical features and other sleep abnormalities.ResultsOut of 400, 86 patients presented RLS (21.5%; mean age 48.8 ± 13.8 y), being more frequent in females (p < 0.005). Forty-eight individuals (12% mean age 50.7 ± 13.1 y) had moderate/severe RLS, 14 reported symptoms prior to hemodialysis, 13 described family history of RLS, and eight described symptoms as disturbing during dialysis. RLS cases showed lower hemoglobin (p < 0.005), poorer quality of sleep (Pittsburgh Sleep Quality Index >5, p = 0.002), higher scores on the Beck Depression Inventory Scale (p < 0.005), greater scores on the Charlson Comorbidity Index (p = 0.01) and the Epworth Sleepiness Scale (p = 0.001) and higher risk of obstructive sleep apnea (OSA; Berlin questionnaire, p = 0.01). Hypertension was more frequent in cases with moderate/severe RLS (p = 0.01) and remained after controlling for the risk of OSA (p = 0.02).ConclusionIn ESRD patients in hemodialysis, RLS is present in 21.5%; 16% report symptoms prior to hemodialysis and a family history of RLS. Symptoms are disturbing during hemodialysis in 9% of cases. RLS is associated with lower hemoglobin, worse sleep quality, excessive daytime sleepiness, depressive symptoms and higher risk of OSA. Hypertension is associated with moderate/severe RLS.     

Assessing health-related quality of life in patients with restless legs syndrome in Korea: Comparison with other chronic medical diseases

BackgroundThere have been few quality of life (QoL) studies of patients with restless legs syndrome (RLS) in Asian countries. We studied the QoL of patients with RLS and compared it to normal controls and patients with hypertension, type 2 diabetes, or osteoarthritis in Korea.MethodsA total of 215 RLS patients (141 female; mean age 51.7 ± 13.5) were enrolled. All patients completed the questionnaires, including all the Korean versions of SF-36, RLS QoL, the International RLS Severity scale (IRLS), the Pittsburgh Sleep Quality Index (PSQI), and the Beck Depression Inventory-2 (BDI-2). These results were compared with the scores from normal controls (N = 214) and from patients with hypertension (196), uncomplicated type 2 diabetes (185), or osteoarthritis of the knee (177).ResultsThe SF-36 QoL in patients with RLS was lower than that of the normal controls, and even lower than patients with hypertension or diabetes, but higher than those with osteoarthritis. The SF-36 Qol of RLS patients showed a significantly negative correlation with the severity of RLS symptoms (r = ?0.430, p < 0.001) and the severity of depression (r = ?0.565, p < 0.001), but was not significantly related to gender, age, or age-of-symptom onset (early or late-onset). Step-wise multiple regression identified three factors related to SF-36 QoL: depression (46.5% of RLS had responses on BDI-2 indicating depression) (β = ?.899, p < 0.001), RLS symptom severity (K-IRLS) (β = ?.718, p < 0.001), and gender (female) (β = ?6.128, p = 0.007).ConclusionsThese findings show that RLS has a considerable impact on the QoL of Koreans, which is comparable with studies of western countries. The QoL impairment relates to the degree of depression with RLS for Koreans.     

Voxel-based morphometry in unmedicated patients with restless legs syndrome

BackgroundThe pathophysiology of restless legs syndrome (RLS) is not yet understood. A prior voxel-based morphometry (VBM) study reported gray matter increase in the pulvinar of the thalamus in a group of patients, most of whom were on medical treatment. Since there is evidence that medication can change the volume of cerebral structures, the question arises as to whether the reported morphometric alterations are caused by the RLS itself or, alternatively, are a consequence of drug treatment. To address this issue, we performed VBM in unmedicated RLS patients.MethodsFourteen patients with idiopathic RLS with no (n = 11) or only minimal (n = 3) treatment exposure in the past and 14 age- and sex-matched healthy subjects were investigated. All subjects were free of psychotropic drugs for at least 4 months. Morphological data were analyzed by using optimized VBM.ResultsWe did not detect any structural changes except for slightly increased gray matter density in the ventral hippocampus (p = 0.046 on the left and p = 0.055 on the right side) and in the middle orbitofrontal gyrus (p = 0.046 on the right and p = 0.097 on the left side).ConclusionOur study could not confirm the findings of a prior study. A possible explanation for the divergent findings is the difference between the populations examined. Since, in our study, essentially treatment-naïve patients were investigated, it is possible that the prior findings reflect treatment-induced effects on cerebral morphology in RLS.     

Sertraline and periodic limb movements during sleep: an 8-week open-label study in depressed patients with insomnia

BackgroundPrevious studies have reported that selective serotonin reuptake inhibitors (SSRIs) might induce or exacerbate periodic limb movements during sleep (PLMS). However, most of these studies were retrospective and cross-sectional studies with small sample sizes on a selective SSRI, fluoxetine. Because different SSRIs have different pharmacologic profiles, it was not certain if other SSRIs also might lead to PLMS.MethodsData were taken from an open-label 8-week trial of sertraline in depressive patients with insomnia (n = 31). Depressed patients were administered sertraline 50 mg at 8:00 am on the first day, and the dosage was subsequently titrated up to a maximum of 200 mg daily during the 8-week trial. All participants were tested by repeated polysomnography (PSG) (baseline, first day, 14th day, 28th day, and 56th day). Periodic leg movements (PLM) were visually counted and the PLM index (PLMI) was calculated. PLMS was defined as PLMI ⩾5, and significant PLMS was defined as PLMI ⩾15.ResultsCompared with baseline (PLMI, 3.6 ± 1.5), all PLMI indices increased on the immediate administration of sertraline on the first day (PLMI, 5.1 ± 3.9). From the 14th day onward, PLMI became stable and significantly higher than baseline and the first day (8.7 ± 3.1 on the 14th day, 8.3 ± 3.7 on the 28th day, and 8.5 ± 3.6 on the 56th day; F[11.81]; P = .003). The clinical responses and PSG characteristics continuously improved during the 8-week trial. The PLMS group (PLMI ⩾5) had a higher arousal index (AI) than the non-PLMS group on the 14th day (9.4 ± 5.5 vs 5.2 ± 3.7; t test, 4.22; P = .03) and the 56th day (8.1 ± 5.5 vs 4.3 ± 3.7; z score, 3.11; P = .04); albeit, there was no significant clinical disturbances in the PLMS group.ConclusionsPLMS were increased during sertraline treatment, but only a few of the PLMS reached the significant level. This effect of sertraline on PLMS might be dosage dependent. Although the sertraline-induced PLMS did not seem to cause significant clinical disturbance, the PLMS group (PLMI ⩾5) had a higher AI than the non-PLMS group. Thus clinicians should pay more attention to PLMS during SSRI antidepressant treatment.     

Long-term use of pramipexole in the management of restless legs syndrome

ObjectiveFew studies have examined the long-term use of dopamine agonists for restless legs syndrome (RLS). We report a cohort study of 50 patients initially prescribed pramipexole between 1998 and 2002. The objective was to determine duration of treatment, long-term efficacy, development of side effects and augmentation over an extended period.MethodsWe performed a long-term analysis on a previously reported group of patients initially followed for a mean of 27.2 months. Data were collected using retrospective chart reviews, written surveys and systematic telephone interviews.ResultsPramipexole was used for a mean of 8 years (range 0.6–12 years). Nine (18%) discontinued pramipexole because of poor efficacy (four), impulse control disorders (ICD) (two), augmentation (one) and resolved symptoms (two). Pramipexole was reported completely effective in 40% (compared to 67% at the end of the initial study), partially effective in 58% and ineffective in 2%. The median daily dose increased from 0.38 mg after initial stabilization to 1.0 mg at the end of the study. As many as 74% of patients experienced side effects. A total of 56% reported daytime sleepiness including 10% reporting sleep attacks while driving and 10% developed ICDs. Augmentation developed in 42% of patients, after a mean of 16.5 months, and no later than 4.1 years after commencing treatment. A total of 28% needed additional non-dopaminergic medications.ConclusionThe efficacy of pramipexole dropped with time, with increase in dose and addition of other agents, although the majority of patients remained on the drug. Problems included the development of augmentation within the first 4 years of therapy and side effects such as sleepiness increasing with time and the development of ICDs. The study highlights the need for further research into alternative non-dopaminergic treatments for RLS.     

A randomized,double-blind, 6-week,dose-ranging study of pregabalin in patients with restless legs syndrome

ObjectiveThis study evaluated the dose-related efficacy and safety of pregabalin in patients with idiopathic restless legs syndrome (RLS).MethodsThis six-arm, double-blind, placebo-controlled, dose–response study randomized patients (N = 137) with moderate-to-severe idiopathic RLS in an equal ratio to placebo or pregabalin 50, 100, 150, 300, or 450 mg/day. The dose–response was characterized using an exponential decay model, which estimates the maximal effect (E_max) for the primary endpoint, the change in the International Restless Legs Study Group Rating Scale (IRLS) total score from baseline to week 6 of treatment. Secondary outcomes included Clinical Global Impressions-Improvement Scale (CGI-I) responders, sleep assessments, and safety.ResultsThe separation of treatment effect between placebo and pregabalin began to emerge starting at week 1 which continued and increased through week 6 for all dose groups. The IRLS total score for pregabalin was dose dependent and well characterized for change from baseline at week 6. The model estimated 50% (ED₅₀) and 90% (ED₉₀) of the maximal effect in reducing RLS symptoms that occurred at pregabalin doses of 37.3 and 123.9 mg/day, respectively. A higher proportion of CGI-I responders was observed at the two highest doses of pregabalin (300 and 450 mg/day) versus placebo. Dizziness and somnolence were the most common adverse events and appeared to be dose-related.ConclusionsIn this 6-week phase 2b study, pregabalin reduced RLS symptoms in patients with moderate-to-severe idiopathic RLS. The symptom reduction at week 6 was dose-dependent with 123.9 mg/day providing 90% efficacy. Pregabalin was safe and well tolerated across the entire dosing range.     

Elevated C-reactive protein is associated with severe periodic leg movements of sleep in patients with restless legs syndrome

BackgroundRestless legs syndrome (RLS) is a common sleep disorder in which urges to move the legs are felt during rest, are felt at night, and are improved by leg movement. RLS has been implicated in the development of cardiovascular disease. Periodic leg movements (PLMs) may be a mediator of this relationship. We evaluated systemic inflammation and PLMs in RLS patients to further assess cardiovascular risk.Methods137 RLS patients had PLM measurements taken while unmedicated for RLS. Banked plasma was assayed for high sensitivity C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-alpha).ResultsMean (SD) PLM index was 19.3 (22.0). PLMs were unrelated to TNF-a and IL-6, but were modestly correlated with log CRP (r(129) = 0.19, p = 0.03). Those patients with at least 45 PLMs/h had an odds ratio of 3.56 (95% CI 1.26–10.03, p = 0.02, df = 1) for having elevated CRP compared to those with fewer than 45 PLMs/h. After adjustment for age, race, gender, diabetes, hypertension, hyperlipidemia, inflammatory disorders, CRP-lowering medications, and body mass index, the OR for those with ?45 PLMs/h was 8.60 (95% CI 1.23 to 60.17, p = 0.03, df = 10).ConclusionsPLMs are associated with increased inflammation, such that those RLS patients with at least 45 PLMs/h had more than triple the odds of elevated CRP than those with fewer PLMs. Further investigation into PLMs and inflammation is warranted.     

Restless legs syndrome, sleep impairment, and fatigue in chronic obstructive pulmonary disease

ObjectiveTo investigate the frequency of factors associated with restless legs syndrome (RLS) in patients with chronic obstructive pulmonary disease (COPD).MethodsRLS diagnosis was investigated (International RLS Study Group, IRLSSG) and severity was assessed (IRLS rating scale) in 104 consecutive COPD patients (age 69.1 ± 8). Other measures were dyspnea severity (Modified Medical Research Council, MMRC), sleep quality (Pittsburgh Sleep Quality Index, PSQI), daytime somnolence (Epworth Sleepiness Scale, ESS), depressive symptoms (Beck Depression Inventory, BDI-II), and fatigue (Fatigue Severity Scale, FSS). Laboratory values included hemoglobin, ferritin, creatinine, and fibrinogen.ResultsThirty-two patients (30.8%) were diagnosed with RLS (65.6% women), which was moderate/severe (IRLS >11) in 26 (81.3%). RLS symptoms started after age 40 in most patients (93.3%). RLS patients had poorer sleep quality (PSQI >5 = 59.6%; p = 0.002), worse fatigue (FSS >27 = 51%; p = 0.005), and more depressive symptoms (BDI-II >10 = 14.4%; p = 0.005). Patients with RLS also presented more severe dyspnea (p = 0.009) and lower creatinine levels (p = 0.005). Overall, fatigue severity was correlated with older age (p = 0.001); level of dyspnea was positively correlated with PSQI and FSS (p < 0.005) and negatively correlated with ferritin (p = 0.03) and creatinine (p = 0.005), and PSQI scores correlated positively with FSS (p < 0.005) and negatively with ferritin (p = 0.005) and creatinine (p = 0.02). Quality of sleep was independently predicted by dyspnea severity and creatinine and fatigue by age and depression.ConclusionRLS is common in COPD. Patients with RLS have low creatinine, poorer quality of sleep, and more fatigue and depressive symptoms. RLS symptom severity is correlated to lower ferritin and severity of dyspnea.     

Assessment of nitric oxide, advanced oxidation protein products, malondialdehyde, and thiol levels in patients with restless legs syndrome

ObjectivesWe aimed to determine the importance of oxidative stress in the pathogenesis of restless legs syndrome (RLS) by quantification of advanced oxidation protein products and total thiol levels (as markers of oxidative protein damage), nitric oxide levels (as an antioxidant and endothelial function), and malondialdehyde levels (as a marker of lipid peroxidation) in patients with RLS.Design and methodsA total of 22 patients with primary RLS were enrolled in the study and 20 age-and-gender-matched healthy subjects were enrolled as a control group. Serum nitric oxide, malondialdehyde, thiol levels, and plasma advanced oxidation protein products levels were determined by spectrophotometric methods.ResultsSerum nitric oxide and thiol levels were lower in the patient group than in controls (p = 0.007 and p = 0.017, respectively). Plasma advanced oxidation protein products levels and serum malondialdehyde levels were found to be higher in patients with RLS than in controls (p = 0.017 and p = 0.008, respectively). Serum malondialdehyde level was found to be positively correlated with plasma advanced oxidation protein products levels (p = 0.039). Serum thiol level was found to be negatively correlated with plasma advanced oxidation protein products levels (p = 0.030).ConclusionsIncreased advanced oxidation protein products, malondialdehyde levels, and decreased thiol and nitric oxide levels, may suggest that patients with RLS are under oxidative stress. Although both lipid peroxidation and protein oxidation may have a role in atherosclerosis in RLS, those factors may be related to the pathogenesis of RLS.     

Autonomic complaints in patients with restless legs syndrome

BackgroundData regarding autonomic function in restless legs syndrome (RLS) are limited to heart rate and blood pressure changes in cases with periodic limb movements (PLMS).MethodsWe compared autonomic symptoms of 49 subjects with RLS vs 291 control subjects using the Scales for Outcome in Parkinson disease-Autonomic (SCOPA-AUT) questionnaire, consisting of 23 items in six domains scored from 0 to 3. The total score and domain scores were transformed to 0–100 points. Subjects with neurodegenerative disorders (i.e., dementia, Parkinsonism) were excluded.ResultsThe RLS group was younger (mean ± standard deviation, 77.9 ± 8.0 vs 80.5 ± 7.9 years; P = .03) and included more women (84% vs 69%; P = .04). The mean SCOPA-AUT total score was higher in the RLS group compared with the control group (20 ± 11 vs 16 ± 9; P = .005). Additionally the RLS group had abnormalities in gastrointestinal, cardiovascular, and pupillomotor domains. When comparing the percentage of subjects with any complaint on individual questions (score of ⩾1), the RLS group had a greater number of subjects with sialorrhea, constipation, early abdominal fullness, lightheadedness when standing, and heat intolerance.ConclusionsAutonomic complaints, especially gastrointestinal, cardiovascular, and oversensitivity to light, were significantly increased in subjects with RLS. Causes for autonomic dysfunction in RLS require further investigation.     

Sleep disorders and daytime sleepiness in children with attention-deficit/hyperactivity disorder: A two-night polysomnographic study with a multiple sleep latency test

ObjectiveTo evaluate sleep macrostructure, sleep disorders incidence and daytime sleepiness in attention-deficit/hyperactivity disorder (ADHD) affected children compared with controls.MethodsThirty-one patients (26 boys, 5 girls, mean age 9.3 ± 1.7, age range 6–12 years) with ADHD diagnosed according to DSM-IV criteria, without comorbid psychiatric or other disorders, as never before pharmacologically treated for ADHD. The controls were 26 age- and sex-matched children (22 boys, 4 girls, age range 6–12 years, mean age 9.2 ± 1.5). Nocturnal polysomnography (PSG) was performed for two nights followed by the multiple sleep latency test (MSLT).ResultsNo differences between the two groups comparing both nights were found in the basic sleep macrostructure parameters or in the time (duration) of sleep onset. A first-night effect on sleep variables was apparent in the ADHD group. Occurrence of sleep disorders (sleep-disordered breathing [SDB], periodic limb movements in sleep [PLMS], parasomnias) did not show any significant differences between the investigated groups. A statistically significant difference (p = 0.015) was found in the trend of the periodic limb movement index (PLMI) between two nights (a decrease of PLMI in the ADHD group and an increase of PLMI in the control group during the second night). While the mean sleep latency in the MSLT was comparable in both groups, children with ADHD showed significant (sleep latency) inter-test differences (between tests 1 and 2, 1 and 4, 1 and 5, p < 0.01).ConclusionAfter the inclusion of adaptation night and exclusion of psychiatric comorbidities, PSG showed no changes in basic sleep parameters or sleep timing, or in the frequency of sleep disorders (SDB, PLMS) in children with ADHD compared with controls, thus not supporting the hypothesis that specific changes in the sleep macrostructure and sleep disturbances are connected with ADHD. A first-night effect on sleep variables was apparent only in the ADHD group. Though we found no proof of increased daytime sleepiness in children with ADHD against the controls, we did find significant vigilance variability during MSLT in the ADHD group, possibly a sign of dysregulated arousal.     

PLM detection by actigraphy compared to polysomnography: a validation and comparison of two actigraphs

ObjectiveTo compare periodic leg movement (PLM) counts obtained with polysomnography (PSG) to those obtained from actigraphy with two devices (Actiwatch and PAM-RL).MethodsTwenty-four patients underwent full night actigraphy with Actiwatch from both legs and simultaneous PSG. Out of these patients, 10 had additional actigraphy with PAM-RL. Bilateral and unilateral PLM indices (PLMI) for both actigraphs were calculated for time in bed and compared to polysomnographic PLMI. Additionally, a comparison between the two different actigraphs was performed.ResultsPLMI obtained with Actiwatch were significantly lower than those obtained with PSG (21.2 ± 25.6/h versus 34.4 ± 30.7/h; p < 0.001), whereas the PLMI from PAM-RL were significantly higher than in PSG (63.6 ± 39.3/h versus 37.0 ± 33.5/h; p = 0.009). In direct comparison, Actiwatch gave significantly lower PLMI than the PAM-RL (p = 0.005). The correlations between Actiwatch and PSG (rho = 0.835, p < 0.001), PAM-RL and PSG (rho = 0.939, p < 0.001), and Actiwatch and PAM-RL (rho = 0.915, p < 0.001) were significant. Unilateral actigraphy compared to standard PSG gave less consistent findings. When comparing different settings of the PAM-RL, manual threshold setting resulted in PLMI that were no longer different from PSG (p = 0.074), in contrast to the default threshold setting.ConclusionsThe Actiwatch underestimated and the PAM-RL overestimated PLMI compared to PSG. Whereas PLMI obtained with two actigraphs and PSG were highly correlated, they differed in mean values. Therefore, PSG, actigraphy and also the different actigraphs cannot be interchanged in longitudinal studies, and actigraphy should not be used for diagnostic decision making based on PLM indices. The best approximation to PSG PLMI was achieved by using manual threshold setting with the PAM-RL.     

Investigating the response to intravenous iron in restless legs syndrome: an observational study

ObjectiveTo investigate the effect of intravenous (IV) iron (500 mg ferric carboxymaltose [FCM] as a single dose) on restless legs syndrome (RLS) severity on a day-to-day basis.MethodsTwenty patients with RLS and absolute or functional iron deficiency or low normal serum ferritin (<45 μg/l) were included. Change of RLS severity was evaluated using the International RLS severity scale (IRLS) and the RLS-severity diary (RLS-SD) which evaluates symptom severity over a 6-h period on an 11-point numerical Likert scale, four times a day.ResultsTwelve patients reported that IV FCM improved RLS (“responders”). IRLS score decreased from 30.1 (±5.9) to 23.07 (±9.5) (p = 0.001) in the whole group and from 28.3 (±6.1) to 18.3 (±8.0) (p = 0.002) in the responder group three weeks after IV FCM treatment. A clinically relevant effect of IV iron on RLS severity could be seen as early as day eight. The responder group differed from the non-responder group in tendency by being younger (p = 0.064), having a lower serum ferritin level at baseline (p = 0.097), and presenting a lower number of comorbid conditions.ConclusionsFCM led to a considerable improvement in RLS in the responder group within about one week. These findings are clinically relevant, especially for patients with severe RLS symptoms and iron deficiency, since a change or uptitration of RLS-specific medication can be avoided or postponed in these patients due to the rapid response to IV FCM treatment.     

Effectiveness of a placebo intervention on visually induced nausea in women – A randomized controlled pilot study

ObjectiveImprovement of nausea by placebo interventions has recently been demonstrated in clinical trials and experimental settings. However, many questions regarding placebo effects on nausea remain unanswered. For example, nausea reduction in women could only be achieved when the placebo intervention was “enhanced” by conditioning, while men responded primarily to verbally suggested improvement. It is unclear whether these findings are generalizable or were due to situational variables. In this pilot study, we investigated the effects of sham acupuncture point stimulation and verbal suggestions on visually-induced nausea in a female population.MethodsIn a within-subjects design, 21 healthy female volunteers underwent both a placebo condition and a natural history condition (control condition) in a randomized order on two separate days. On both days, nausea was induced through optokinetic stimulation. On the placebo day, participants received sham acupuncture point stimulation together with positive verbal suggestions of nausea improvement. Expected and perceived nausea severity as well as symptoms of motion sickness were repeatedly assessed.ResultsTwenty participants completed both testing days. Participants developed significantly less nausea on the placebo day compared to the control day (p < 0.001), and the effect size of placebo-induced nausea reduction was large (partial η² = 0.71). Symptoms of motion sickness were also reduced (p = 0.003). Expectation of nausea decreased following the placebo intervention as compared to no treatment (p = 0.030), indicating successful expectancy manipulation.ConclusionSham acupuncture point stimulation combined with verbal suggestions induced a significant placebo effect on visually-induced nausea in women.     

Increased prevalence of nocturnal smoking in restless legs syndrome (RLS)

ObjectiveWe investigated the prevalence of nocturnal smoking (NS) in patients with RLS.MethodsOne hundred RLS patients living in Emilia-Romagna (Northern Italy) and 100 matched controls, randomly selected from the general population, underwent interviews for the presence of nocturnal smoking and for obsessive-compulsive traits, depression, excessive daytime sleepiness (EDS) and subjective sleep quality.ResultsNS was more prevalent in RLS patients than controls (lifetime prevalence: 12% vs. 2%, P = 0.012). Patients with NS had more frequently Sleep-Related Eating Disorders (SRED) than patients without NS (83.3% vs. 26.1%, P = 0.0002). Pathological and borderline Maudsley Obsessive-Compulsive Inventory (MOCI) values as well as pathological values at the Beck Depression Inventory (BDI) increased from controls to RLS patients without NS to RLS patients with NS (P = 0.005 and P = 0.01, respectively).ConclusionsWe demonstrate an increased prevalence of NS in patients with RLS, in many cases associated with increased SRED. NS may be associated with psychopathological traits in RLS and may be relevant in the management of RLS patients.     

Efficacy of oral iron in patients with restless legs syndrome and a low-normal ferritin: A randomized, double-blind, placebo-controlled study

Background and PurposeRestless Legs Syndrome (RLS) is a primary disorder of sensation that affects sleep and has been associated with iron deficiency. The purpose of this study was to determine if symptomatic RLS patients with low-normal serum ferritin levels benefit from oral iron replacement.Patients and MethodsThis was a randomized, placebo-controlled, double-blinded study. Eligible patients were randomized to oral iron therapy vs. appearance-matched placebo and followed over a 12 week period.ResultsBaseline International Restless Leg Scale (IRLS) scores for the treatment (24.8 ± 5.72) and placebo (23.0 ± 5.03) groups were similar. Baseline ferritin levels for the treatment (40.6 ± 15.3 ng/ml) and placebo (36.7 ± 20.8 ng/ml) groups were also similar. After 12 weeks, IRLS scores decreased more in the treatment arm (10.3 ± 7.40) than in the placebo arm (1.14 ± 5.64), (p = 0.01). Ferritin levels increased more in the treatment arm (25.1 ± 20.3 ng/ml) than in the placebo arm (7.5 ± 13.7 ng/ml), (p = 0.04). We observed a nonsignificant trend toward improved quality of life in the treated patients, (p = 0.07).ConclusionsThis is the first double-blinded, placebo-controlled study to demonstrate statistically significant improvement in RLS symptoms using oral iron therapy in patients with low-normal ferritin. The findings from this study suggest that additional larger randomized placebo-controlled trials of iron as treatment for patients with low-normal ferritin are warranted.