Restless Legs Syndrome (RLS) in anemic patients with Congestive Heart Failure and Chronic Renal Failure: Lack of effect of anemia treatment

Prognostic Impact of Sleep Patterns and Related-Drugs in Patients with Heart Failure

Sleep disturbances are frequent among patients with heart failure (HF). We hypothesized that self-reported sleep disturbances are associated with a poor prognosis in patients with HF. A longitudinal study of 119 patients with HF was carried out to assess the association between sleep disturbances and the occurrence of major cardiovascular events (MACE). All patients with HF completed self-administered questionnaires on sleepiness, fatigue, insomnia, quality of sleep, sleep patterns, anxiety and depressive symptoms, and central nervous system (CNS) drugs intake. Patients were followed for a median of 888 days. Cox models were used to estimate the risk of MACE associated with baseline sleep characteristics. After adjustment for age, the risk of a future MACE increased with CNS drugs intake, sleep quality and insomnia scores as well with increased sleep latency, decreased sleep efficiency and total sleep time. However, after adjustment for left ventricular ejection fraction and hypercholesterolemia the HR failed to be significant except for CNS drugs and total sleep time. CNS drugs intake and decreased total sleep time were independently associated with an increased risk of MACE in patients with HF. Routine assessment of self-reported sleep disturbances should be considered to prevent the natural progression of HF.

Iron for the treatment of restless legs syndrome

BACKGROUND

Restless legs syndrome (RLS) is a common neurologic disorder that is associated with peripheral iron deficiency in a subgroup of patients. It is unclear whether iron therapy is effective treatment for RLS.

OBJECTIVES

To evaluate the efficacy and safety of oral or parenteral iron for the treatment of restless legs syndrome (RLS) when compared with placebo or other therapies.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PsycNFO, and CINAHL for the time period January 1995 to September 2017. We searched reference lists for additional published studies. We searched Clinicaltrials.gov and other clinical trial registries (September 2017) for ongoing or unpublished studies.

SELECTION CRITERIA

Controlled trials comparing any formulation of iron with placebo, other medications, or no treatment, in adults diagnosed with RLS according to expert clinical interview or explicit diagnostic criteria.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed trial quality, with discussion to reach consensus in the case of any disagreement. The primary outcome considered in this review was restlessness or unpleasant sensations, as experienced subjectively by the patient. We combined treatment/control differences in the outcomes across studies using random-effects meta-analyses. We analysed continuous data using mean differences (MDs) where possible and performed standardised mean difference (SMD) analyses when different measurements were used across studies. We calculated risk ratios (RRs) for dichotomous data using the Mantel-Haenszel method and 95% confidence intervals (CIs). We analysed study heterogeneity using the I² statistic. We used standard methodological procedures expected by Cochrane. We performed GRADE analysis using GRADEpro.

MAIN RESULTS

We identified and included 10 studies (428 total participants, followed for 2-16 weeks) in this review. Our primary outcome was restlessness or uncomfortable leg sensations, which was quantified using the International Restless Legs Scale (IRLS) (range, 0 to 40) in eight trials and a different RLS symptom scale in a ninth trial. Nine studies compared iron to placebo and one study compared iron to a dopamine agonist (pramipexole). The possibility for bias among the trials was variable. Three studies had a single element with high risk of bias, which was lack of blinding in two and incomplete outcome data in one. All studies had at least one feature resulting in unclear risk of bias.Combining data from the seven trials using the IRLS to compare iron and placebo, use of iron resulted in greater improvement in IRLS scores (MD -3.78, 95% CI -6.25 to -1.31; I²= 66%, 7 studies, 345 participants) measured 2 to 12 weeks after treatment. Including an eighth study, which measured restlessness using a different scale, use of iron remained beneficial compared to placebo (SMD -0.74, 95% CI -1.26 to -0.23; I² = 80%, 8 studies, 370 participants). The GRADE assessment of certainty for this outcome was moderate.The single study comparing iron to a dopamine agonist (pramipexole) found a similar reduction in RLS severity in the two groups (MD -0.40, 95% CI -5.93 to 5.13, 30 participants).Assessment of secondary outcomes was limited by small numbers of trials assessing each outcome. Iron did not improve quality of life as a dichotomous measure (RR 2.01, 95% CI 0.54 to 7.45; I²=54%, 2 studies, 39 participants), but did improve quality of life measured on continuous scales (SMD 0.51, 95% CI 0.15 to 0.87; I²= 0%, 3 studies, 128 participants), compared to placebo. Subjective sleep quality was no different between iron and placebo groups (SMD 0.19, 95% CI -0.18 to 0.56; I² = 9%, 3 studies, 128 participants), nor was objective sleep quality, as measured by change in sleep efficiency in a single study (-35.5 +/- 92.0 versus -41.4 +/- 98.2, 18 participants). Periodic limb movements of sleep were not significantly reduced with iron compared to placebo ( SMD -0.19, 95% CI -0.70 to 0.32; I² = 0%, 2 studies, 60 participants). Iron did not improve sleepiness compared to placebo, as measured on the Epworth Sleepiness Scale (data not provided, 1 study, 60 participants) but did improve the daytime tiredness item of the RLS-6 compared to placebo (least squares mean difference -1.5, 95% CI -2.5 to -0.6; 1 study, 110 participants). The GRADE rating for secondary outcomes ranged from low to very low.Prespecified subgroup analyses showed more improvement with iron in those trials studying participants on dialysis. The use of low serum ferritin levels as an inclusion criteria and the use or oral versus intravenous iron did not show significant subgroup differences.Iron did not result in significantly more adverse events than placebo (RR 1.48, 95% CI 0.97 to 2.25; I²=45%, 6 studies, 298 participants). A single study reported that people treated with iron therapy experienced fewer adverse events than the active comparator pramipexole.

AUTHORS' CONCLUSIONS

Iron therapy probably improves restlessness and RLS severity in comparison to placebo. Iron therapy may not increase the risk of side effects in comparison to placebo. We are uncertain whether iron therapy improves quality of life in comparison to placebo. Iron therapy may make little or no difference to pramipexole in restlessness and RLS severity, as well as in the risk of adverse events. The effect on secondary outcomes such as quality of life, daytime functioning, and sleep quality, the optimal timing and formulation of administration, and patient characteristics predicting response require additional study.

Evidence-based and consensus clinical practice guidelines for the iron treatment of restless legs syndrome/Willis-Ekbom disease in adults and children: an IRLSSG task force report

BACKGROUND

Brain iron deficiency has been implicated in the pathophysiology of RLS, and current RLS treatment guidelines recommend iron treatment when peripheral iron levels are low. In order to assess the evidence on the oral and intravenous (IV) iron treatment of RLS and periodic limb movement disorder (PLMD) in adults and children, the International Restless Legs Syndrome Study Group (IRLSSG) formed a task force to review these studies and provide evidence-based and consensus guidelines for the iron treatment of RLS in adults, and RLS and PLMD in children.

METHODS

A literature search was performed to identify papers appearing in MEDLINE from its inception to July 2016. The following inclusion criteria were used: human research on the treatment of RLS or periodic limb movements (PLM) with iron, sample size of at least five, and published in English. Two task force members independently evaluated each paper and classified the quality of evidence provided.

RESULTS

A total of 299 papers were identified, of these 31 papers met the inclusion criteria. Four studies in adults were given a Class I rating (one for IV iron sucrose, and three for IV ferric carboxymaltose); only Class IV studies have evaluated iron treatment in children. Ferric carboxymaltose (1000 mg) is effective for treating moderate to severe RLS in those with serum ferritin <300 μg/l and could be used as first-line treatment for RLS in adults. Oral iron (65 mg elemental iron) is possibly effective for treating RLS in those with serum ferritin ≤75 μg/l. There is insufficient evidence to make conclusions on the efficacy of oral iron or IV iron in children.

CONCLUSIONS

Consensus recommendations based on clinical practice are presented, including when to use oral iron or IV iron, and recommendations on repeated iron treatments. New iron treatment algorithms, based on evidence and consensus opinion have been developed.

Restless legs syndrome in hemodialysis patients in Iran

Restless legs syndrome (RLS) is a common sleep disorder that can present secondary to medical conditions such as renal failure. This study aimed to evaluate RLS frequency and its related factors in chronic renal failure patients treated with hemodialysis. In a cross-sectional design, 163 patients with chronic renal failure were consecutively enrolled from hemodialysis center at Rasool-Akram hospital. Demographics, clinical and laboratory data were recorded. Patients were screened for presence and severity of RLS according to the four International Restless Legs Syndrome Group (IRLSSG) diagnostic criteria and severity scale. Patients with and without RLS were compared using SPSS statistical software (Version 16.0). Sixty-one patients (37.4 %) were diagnosed with RLS. Mean age in RLS group was significantly higher (65.2 ± 9.3 years) than RLS-negative group (59.0 ± 14.7 years; P = 0.004). Serum creatinine level was significantly higher in patients with RLS (7.6 ± 2.1 mg/dl vs. 6.7 ± 1.8 mg/dl; P = 0.009). Glomerular filtration rate in RLS patients was lower than other patients (9.2 ± 3.1 ccs/min vs. 11.6 ± 4.8 ccs/min; P = 0.0001). Patients with RLS had shorter sleep duration, and higher incidence of insomnia, daytime sleepiness, and sedative-hypnotic medication usage (P < 0.05). There was no significant difference between RLS-positive and RLS-negative patients in terms of renal failure pathology, dialysis frequency per week, dose of dialysis, duration of dialysis, renal transplantation, and history of diabetes and hypertension. Hemodialysis patients have a high prevalence of RLS which deserves special attention and specific treatment.

Iron for restless legs syndrome

BACKGROUND

Restless legs syndrome (RLS) is a common neurologic syndrome and is associated with iron deficiency in many patients. It is unclear whether iron therapy is effective treatment for RLS.

OBJECTIVES

The objective of this review was to assess the effects of iron supplementation (oral or intravenous) for patients with RLS.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (Jan 1995 to April 2011); EMBASE (Jan 1995 to April 2011); PsycINFO (Jan 1995 to April 2011); and CINAHL (Jan 1995 to April 2011). Corresponding authors of included trials and additional members of the International Restless Legs Syndrome Study Group were contacted to locate additional published or unpublished trials.

SELECTION CRITERIA

Controlled trials comparing any formulation of iron with placebo, other medications, or no treatment in adults diagnosed with RLS according to expert clinical interview or explicit diagnostic criteria.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data and at least two authors assessed trial quality. We contacted trial authors for missing data.

MAIN RESULTS

Six studies (192 total subjects) were identified and included in this analysis. The quality of trials was variable. Our primary outcome was restlessness or uncomfortable leg sensations, which was quantified using the IRLS severity scale in four trials and another RLS symptom scale in a fifth trial. Combining data from the four trials using the IRLS severity scale, there was no clear benefit from iron therapy (mean difference in IRLS severity scores of -3.79, 95% CI: -7.68 to 0.10, p = 0.06). However, the fifth trial did find iron therapy to be beneficial (median decrease of 3 points in the iron group and no change in the placebo group on a 10 point scale of RLS symptoms, p = 0.01). Quality of life was improved in the iron group relative to placebo in some studies but not others. Changes in periodic limb movements were not different between groups (measured in two studies). Objective sleep quality, subjective sleep quality and daytime functioning were not different between treatment groups in the studies that assessed them. The single study of subjects with end stage renal disease did show a benefit of therapy. Most trials did not require subjects to have co-morbid iron deficiency and several excluded patients with severe anemia. The single study that was limited to iron deficient subjects did not show clear benefit of iron supplementation on RLS symptoms. There was no clear superiority of oral or intravenous delivery of iron. Iron therapy did not result in significantly more side effects than placebo (RR 1.39, 95% CI 0.85 to 2.27).

AUTHORS' CONCLUSIONS

There is insufficient evidence to determine whether iron therapy is beneficial for the treatment of RLS. Further research to determine whether some or all types of RLS patients may benefit from iron therapy, as well as the best route of iron administration, is needed.

Restless legs syndrome and conditions associated with metabolic dysregulation, sympathoadrenal dysfunction, and cardiovascular disease risk: a systematic review

Restless legs syndrome (RLS) is a distressing sleep and sensorimotor disorder that affects a large percentage of adults in the western industrialized world and is associated with profound reductions in quality of life. However, the etiology of RLS remains incompletely understood. Enhanced understanding regarding both the antecedents and sequelae of RLS could shed new light on the pathogenesis of RLS. Evidence from an emerging body of literature suggests associations between RLS and diabetes, hypertension, obesity, and related conditions linked to sympathetic activation and metabolic dysregulation, raising the possibility that these factors may likewise play a significant role in the development and progression of RLS, and could help explain the recently documented associations between RLS and subsequent cardiovascular disease. However, the relation between RLS and these chronic conditions has received relatively little attention to date, although potential implications for the pathogenesis and treatment of RLS could be considerable. In this paper, we systematically review the recently published literature regarding the association of RLS to cardiovascular disease and related risk factors characterized by sympathoadrenal and metabolic dysregulation, discuss potential underlying mechanisms, and outline some possible directions for future research.