Opioids in the treatment of restless legs syndrome: pharmacological and clinical aspects

The Efficacy and Safety of Pharmacological Treatments for Restless Legs Syndrome: Systemic Review and Network Meta-Analysis

Although various drugs are currently used for restless legs syndrome (RLS) in clinic, selecting appropriate drugs for patients is difficult. This network meta-analysis (NMA) aimed to compare the efficacy and safety of different drugs. After literature searching and screening, 46 trials, including 10,674 participants are included in this NMA. The pooled results showed that, compared with placebo, only levodopa is inefficient to relieve symptoms of RLS. Cabergoline decreases IRLS scores to the greatest extent among all drugs (MD −11.98, 95% CI −16.19 to −7.78). Additionally, pramipexole is superior to ropinirole in alleviating symptoms of RLS (MD −2.52, 95% CI −4.69 to −0.35). Moreover, iron supplement alleviates RLS symptoms significantly compared with placebo in patient with iron deficiency (MD −5.15, 95% CI −8.99 to −1.31), but not for RLS patients with normal serum ferritin level (MD −2.22, 95% CI −6.99 to 2.56). For primary RLS, these drugs are also effective, while there is insufficient data to analyze drug efficacy in secondary RLS. We analyzed risk of common adverse effects of drugs including nausea, somnolence, fatigue, headache and nasopharyngitis. Alpha-2-delta ligands and DAs are favorable choices for both primary and secondary RLS because of their significant efficacy and good tolerability. Iron supplement can significantly alleviate symptoms of RLS patients with iron deficiency than placebo. We recommend gabapentin, gabapentin enacarbil, and pregabalin for clinicians for first consideration mainly because that they rarely cause augmentation. Oxycodone-naloxone could be considered in patients with severe or very severe RLS who failed in treatment with above drugs.

Pramipexole in peritoneal dialysis patients with restless legs syndrome (RLS): a protocol for a multicentre double-blind randomised controlled trial

INTRODUCTION

Restless legs syndrome (RLS) is a common neurological sensorimotor disorder among patients with end stage renal disease. This clinical trial aimed to provide evidence on the efficacy and safety of pramipexole in patients with uremic RLS receiving peritoneal dialysis (PD).

METHODS AND ANALYSIS

This is a 12-week, multicentre, randomised, double-blind, placebo-controlled clinical trial. In total, 104 patients with uremic RLS receiving PD will be enrolled from four hospitals and randomly assigned in a 1:1 ratio to either placebo or pramipexole. We will determine the efficacy of pramipexole in the improvement of International RLS Study Group Rating Scale as the primary outcome, while responder rates for other RLS scales at week 12, change from baseline to week 12 for psychological status, sleep disorder and quality of life and blood pressure represent the secondary outcomes.

ETHICS AND DISSEMINATION

The study was approved by the ethics committees of Peking University First Hospital, Xinqiao hospital of Army Medical University, Cangzhou Center Hospital and Peking University Shenzhen Hospital. The results will be disseminated in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03817554.

The Appropriate Use of Opioids in the Treatment of Refractory Restless Legs Syndrome

Restless legs syndrome (RLS) is a distinct disorder, differing from chronic pain in many ways. Refractory RLS is characterized by unresponsiveness to dopamine agonists or alpha-2-delta ligands due to inadequate efficacy, augmentation, or adverse effects. This may result in severely impaired quality of life, profound insomnia, and suicidal depression. Opioid therapy is a mainstay in the management of these patients. This article summarizes the basic science and clinical evidence in support of their use, including the positive result of a large controlled multicenter study of 306 subjects, and outlines an approach to their use in clinical practice. Treatable explanations for RLS refractoriness, such as low iron stores, and other therapeutic options, such as combination therapy, should be considered before prescribing opioids. The agents most commonly used are oxycodone and methadone, but tramadol, codeine, morphine, and hydrocodone can also be considered. Controlled-release medication should be used for evening dosage and short-acting drugs, if needed, during the day. Effective doses are considerably lower than used for chronic pain (oxycodone 10-30 mg daily; methadone 5-20 mg daily) and the risk of opioid use disorder is relatively low. However, sensible precautions should be undertaken, including assessing opioid risk with standard questionnaires, using an opioid contract, using urine drug screens, consulting state prescription drug monitoring programs, and frequent reevaluation of effectiveness and side effects. Opioid use in selected patients with refractory RLS may be life-transforming with favorable risk-benefit ratio.