Comparison of pregabalin with ondansetron in treatment of uraemic pruritus in dialysis patients: a prospective, randomized, double-blind study

Efficacy and Safety of Pregabalin and Gabapentin for Pruritus: A Systematic Review and Meta-Analysis

CONTEXT

Limited data existed on the efficacy and safety of novel antiepileptic drugs (pregabalin and gabapentin) in treating pruritus.

OBJECTIVES

To assess their role in managing either acute or chronic pruritus.

METHODS

A systematic search was conducted in PubMed, EMBASE, the Cochrane Library, and Web of Science databases for relevant randomized controlled trials. Pooled odd ratio (OR) with 95% CI were performed using RevMan5.4 and R4.3.1.

RESULTS

Analysis of 27 articles involving 2,016 patients showed significant reduction in pruritus incidence (OR, 0.30 [CI, 0.22-0.4]; I2=1%) and improvements in VAS (MD, 2.76 [CI, 0.95-4.57]; I2=98%) and 5-D scores (MD, 3.42 [CI, 2.10-4.75]; I2=92%) with pregabalin/gabapentin compared to controls. Adverse effects mainly included dizziness, somnolence, nausea and vomiting, dry mouth, constipation, and anxiety, with no significant difference between the groups (OR, 1.08 [CI, 0.32-3.59]; I2=76%).

CONCLUSION

The novel antiepileptic drugs pregabalin and gabapentin demonstrated significant therapeutic value in the treatment of pruritus, with a favorable safety profile. Compared to commonly used pruritus treatments such as antihistamines and antidepressants, these medications offered a promising alternative.

Comparison Between Pregabalin and Sertraline in the Treatment of Uremic Pruritus in Patients With Maintenance Hemodialysis

Introduction Pruritus, a medical symptom also known as itch, is characterized by an unpleasant feeling coupled with the urge to scratch. Patients with chronic kidney disease (CKD) often have symptoms of pruritus due to uremia, which has adversely affected their quality of life. The treatment protocol for CKD pruritus is still being debated due to its unclear etiopathogenesis. Pregabalin, an anticonvulsant medication, and sertraline, an antidepressant medication, have been used to treat uremic pruritus (UP) patients on maintenance hemodialysis. Objectives There are no adequate investigations comparing the efficacy of pregabalin and sertraline, particularly in under-resourced countries such as Pakistan. Method The research was a randomized trial for a period of four weeks at the nephrology department of the Mayo Hospital, Lahore. A total of 62 patients were randomly assigned to take either pregabalin (aged 48.06±13.44) or sertraline (aged 47.45±10.97) tablet once a day, a total of 31 patients to each group. The pregabalin group was specified 25 mg for the first week, 50 mg for the second week, and 75 mg for the third and fourth week. Similarly, sertraline was prescribed 25 mg for the first week and 50 mg for the remaining three weeks. However, if the patient shows improvement on the lowest dosage, therapy with the same minimum dose was proposed to be continued. Lastly, the itching score was assessed on the 5D pruritus scale. The Visit 1 (no drug) score was evaluated against post-therapy scores at two-week intervals as Visit 2 (week 2) and Visit 3 (week 4). Statistical analysis was done using the Statistical Product and Service Solutions (SPSS, version 26; IBM SPSS Statistics for Windows, Armonk, NY) with a significance level set at p<0.05 and 95% confidence level. Conclusion This research concluded that both pregabalin and sertraline significantly improved itching intensity in each treatment group; however, there was no significant difference between the two drugs in reducing UP based on the 5D itching scores. In each domain of the 5D pruritus scale, a significant difference was found in post-follow-up pregabalin and sertraline therapy.

Model of Chronic Itch in Aged Mice: Beneficial Effects of Drugs Affecting Descending Modulatory Systems

Pruritus in the elderly, particularly those cases without skin dryness or other identifiable causes, makes treatment challenging due to the lack of evidence regarding the therapeutic effects of antipruritics. This study proposes an age-related alloknesis mouse model for an evaluation system for such cases, and aimed to investigate the effectiveness and mechanisms of action of several drugs commonly used as antipruritics in Japan, utilizing this model. Mice 69-80 weeks old were used as aged mice, and the level of mechanical alloknesis was counted as the number of scratching behaviours in response to innocuous stimuli. Bepotastine, neurotropin, pregabalin, baricitinib, and abrocitinib were used as antipruritics, and yohimbine and methysergide as inhibitors of the descending inhibitory pathway. The findings suggest that mechanical alloknesis in aged mice is a suitable animal model for assessing pruritus in the elderly without xerosis, and pregabalin, neurotropin, baricitinib, and abrocitinib may be effective antipruritics in the elderly through activating both the noradrenergic and serotonergic descending inhibitory pathways. These findings may be useful for the selection of antipruritics for pruritus in the elderly without skin lesions or dryness.

Pathogenesis and Treatment of Pruritus Associated with Chronic Kidney Disease and Cholestasis

Itching is an unpleasant sensation that provokes the desire to scratch. In general, itching is caused by dermatologic diseases, but it can also be caused by systemic diseases. Since itching hampers patients' quality of life, it is important to understand the appropriate treatment and pathophysiology of pruritus caused by systemic diseases to improve the quality of life. Mechanisms are being studied through animal or human studies, and various treatments are being tested through clinical trials. We report current trends of two major systemic diseases: chronic kidney disease and cholestatic liver disease. This review summarizes the causes and pathophysiology of systemic diseases with pruritus and appropriate treatments. This article will contribute to patients' quality of life. Further research will help understand the mechanisms and develop new strategies in the future.

Uremic pruritus: pathophysiology, clinical presentation, and treatments

Uremic pruritus is one of the most common and bothersome symptoms in patients with end-stage renal disease. Most patients with uremic pruritus experience a prolonged and relapsing course and significant impairments of quality of life. The pathophysiology of uremic pruritus is not completely understood. A complex interplay among cutaneous biology and the nervous and immune systems has been implicated, with the involvement of various inflammatory mediators, neurotransmitters, and opioids. Uremic pruritus treatment outcomes are often unsatisfactory. Clinical trials have mostly been small in scale and have reported inconsistent results. Recent evidence shows that gabapentinoids, nalfurafine, and difelikefalin are effective for relieving uremic pruritus in hemodialysis patients. This review provides an overview of the epidemiology and proposed mechanisms of uremic pruritus, then highlights the manifestations of and clinical approach to uremic pruritus. Current evidence regarding treatment options, including topical treatments, treatment of underlying disease, phototherapy, and systemic treatments, is also outlined. With a better understanding of uremic pruritus, more therapeutic options can be expected in the near future.

Obstacles to Early Diagnosis and Treatment of Pruritus in Patients with Chronic Kidney Disease: Current Perspectives

Chronic kidney disease-associated pruritus (CKD-aP) is a common condition amongst patients with advanced chronic kidney disease (CKD). Several studies have confirmed that more than four out of ten early-stage CKD patients suffer from this condition, while its prevalence among CKD patients on dialysis reaches up to seven out of ten. It is noted to be associated with other disabling symptoms and serious outcomes. It has significant impact on sleep, mood, daily activities, and quality of life of CKD patients, and increased mortality risk of patients on hemodialysis. The Dialysis Outcomes and Practice Patterns Study found 17% higher mortality among patients with moderate to extreme pruritus compared with patients with no or mild pruritus. Despite its high prevalence, ill-effect, and suffering associated with it, CKD-aP remains surprisingly under-reported on the patient's part and under-recognized by the healthcare team. Even upon being noticed, it remains unattended and poorly treated. Its etiopathogenesis is complex and not fully understood. Many treatment options are available but good quality evidence about most of those is absent, and to date, only two medications are approved for use in this condition. While a validated guideline is very much required for the benefit of the patients and caretakers, further research on several aspects of this issue is required.

Range and consistency of gastrointestinal outcomes reported in peritoneal dialysis trials: A systematic review

BACKGROUND

Gastrointestinal (GI) health is considered vital to the success of peritoneal dialysis (PD) and is critically important to patients, caregivers and clinicians. However, the multiplicity of GI outcome measures in trials undermines the ability to evaluate the frequency, impact and treatment of GI symptoms in patients receiving PD. Therefore, this study aimed to assess the range and consistency of GI outcomes reported in contemporary PD trials.

STUDY DESIGN

Systematic review.

SETTING AND POPULATION

Individuals with kidney failure requiring PD.

SELECTION CRITERIA

All randomised controlled trials involving patients on PD, identified from the PUBMED, EMBASE and COCHRANE Central Registry of controlled Trials (CENTRAL) database, from January 2010 to July 2022.

INTERVENTIONS

Any PD-related intervention.

OUTCOMES

The frequency and characteristics of GI outcome measures were analysed and classified.

RESULTS

Of the 324 eligible PD trials, GI outcomes were only reported in 61 (19%) trials, mostly as patient-reported outcomes (45 trials; 74%). The most frequently reported outcomes were nausea in 27 (43%), diarrhoea in 26 (43%), vomiting in 22 (36%), constipation in 21 (34%) and abdominal pain in 19 (31%) of trials. PD peritonitis was the primary non-GI outcome reported in 24 (40%) trials, followed by death in 13 (21%) trials) and exit-site infection in 9 (15%) trials). Across all trials, 172 GI outcome measures were extracted and grouped into 29 different outcomes. Nausea and diarrhoea contributed to 16% and 15% of GI outcomes, respectively, while vomiting, constipation and abdominal pain contributed to 13%, 12% and 12%, respectively. Most (90%) GI outcomes were patient-reported adverse effects with no defined metrics. Faecal microbiome was reported as the primary study outcome in 3 (100%) trials using the subjective global assessment score, GI symptom rating scale and faecal microbiological and biochemical analysis. Two trials reported nausea as a primary study outcome using symptom assessment score (SAS) and kidney disease quality of life-short-form-36. One trial each reported anorexia and abdominal pain as the primary study outcome using SAS. Bowel habits, constipation and stool type were also reported as the primary study outcome in one trial each using the Bristol stool form scale. GI bleeding was reported as the secondary outcome in three (37%) out of eight trials reporting it.

LIMITATIONS

Restricted sampling frame to focus on contemporary trials.

CONCLUSIONS

Despite the clinical importance of GI outcomes among patients on PD, they are reported in only 19% of PD trials, using inconsistent metrics, often as patient-reported adverse events. Efforts to standardise GI outcome reporting are critical to optimising comparability, reliability and value of trial evidence to improve outcomes for patients receiving PD.

Pruritus in Chronic Kidney Disease: An Update

Chronic kidney disease-associated pruritus (CKDaP) is an often under-diagnosed and under-recognized condition, despite its considerable prevalence within the chronic kidney disease (CKD) population. Universally accepted guidelines are also lacking. The true prevalence of CKDaP worldwide therefore remains unknown, although its negative impact on mortality and health-related quality of life outcomes is very clear. The pathophysiological mechanisms leading to the onset of CKDaP are only partly understood. CKDaP is currently believed to be caused by a multifactorial process, from local skin changes, metabolic alterations, the development of neuropathy and dysregulation of opioid pathways, and psychological factors. Much work has been carried out towards a more systematic and structured approach to clinical diagnosis. Various tools are now available to assess the severity of CKDaP. Many of these tools require greater validation before they can be incorporated into the guidelines and into routine clinical practice. Further efforts are also needed in order to increase the awareness of clinicians and patients so that they can identify the CKDaP signs and symptoms in a timely manner. Currently established treatment options for CKDaP focus on the prevention of xerosis via topical emollients, the optimization of dialysis management, early referral to kidney transplantation if appropriate, oral antihistamine, and a variety of neuropathic agents. Other novel treatment options include the following: topical analgesics, topical tacrolimus, cannabinoid-containing compounds, antidepressants, oral leukotrienes, opioids, and non-pharmacological alternative therapies (i.e., phototherapy, dietary supplements, acupuncture/acupressure). We provide an updated review on the evidence relating to the epidemiology, the pathophysiology, the clinical assessment and diagnosis, and the management of CKDaP.

[Systemic pruritus: what is new in diagnosis and treatment?]

BACKGROUND

Chronic pruritus is a common symptom of various systemic diseases. In particular, patients with chronic renal failure, hepatobiliary diseases, and myeloproliferative neoplasms are affected.

OBJECTIVES

The purpose of this review is to provide an overview of laboratory chemistry and imaging diagnostics as well as current and novel therapeutic approaches to pruritus of systemic diseases.

MATERIALS AND METHODS

An extensive PubMed search was performed.

RESULTS

To clarify the cause of chronic pruritus, a step-by-step diagnosis is recommended, which is based on the frequency of pruritus-associated diseases. A basic diagnosis enables a cost-effective and targeted clarification at the level of a general practitioner. Current topical and drug therapy recommendations of pruritus in chronic renal failure, hepatobiliary diseases, myeloproliferative neoplasms, and rarer causes are summarized. In addition, novel therapeutic approaches such as the κ‑opioid receptor agonist difelikefalin, bezafibrate, inhibitors of the ileal bile acid transporter (IBAT), and the JAK-STAT pathway are highlighted.

CONCLUSIONS

Chronic pruritus in systemic diseases can be a diagnostic challenge. A staged diagnostic approach facilitates identification of the underlying disease. Improved pathophysiological understanding has led to the first approved therapeutic options for chronic kidney disease-associated and hepatic pruritus.

Comparison of Pregabalin and Ketotifen in Treatment of Uremic Pruritus in Hemodialysis Patients

This study aims to compare the efficiency of Pregabalin and Ketotifen in treatment of uremic pruritus in hemodialysis (HD) patients. Thirty HD patients were randomly divided into two groups: A (Pregabalin 50 mg 3 times a day) and B (Ketotifen 1mg twice a day). Efficacy of treatment and quality of life were weekly evaluated by visual analogue scale (VAS) and Itchy Quality of life, respectively. There was no significant difference between the two groups regarding demographic features, laboratory data, quality of life, and VAS before treatment. In the second week of treatment, the pruritus intensity was significantly lower in the Pregabalin group than the Ketotifen group (p=0.026). The mean of life quality was significantly lower in Ketotifen than Pregabalin group in weeks 1, 2, and 4 (P=0.001, P=0.001, and P=0.036, respectively). There was no significant difference between the two groups regarding the side effects of drugs. This study showed that a higher dose of Pregabalin could be a more effective treatment than Ketotifen without additive side effects in improving the quality of life in dialysis patients. This article is protected by copyright. All rights reserved.

Palliative care for children and young people with stage 5 chronic kidney disease

Death from stage 5 chronic kidney disease (CKD 5) in childhood or adolescence is rare, but something that all paediatric renal physicians and most paediatricians will encounter. In this paper, we present the literature on three key areas of palliative care practice essential to good clinical management: shared decision-making, advance care planning, and symptom management, with particular reference to CKD 5 where kidney transplant is not an option and where a decision has been made to withdraw or withhold dialysis. Some areas of care, particularly with regard to symptom management, have not been well-studied in children and young people (CYP) with CKD 5 and recommendations with regard to drug choice and dose modification are based on adult literature, known pharmacokinetics, and clinical experience.

Clinical management of chronic kidney disease-associated pruritus: current treatment options and future approaches

Chronic kidney disease (CKD)-associated pruritus (CKD-aP) is an underdiagnosed yet severely distressing condition that impacts 60% of patients on dialysis and many nondialysis patients with Stages 3–5 CKD. However, despite its high prevalence, there are currently limited treatment options available for these patients and a lack of treatment guidelines for clinicians. In this manuscript, we reviewed the available literature in order to evaluate the current management and treatment options for CKD-aP, including dialysis management, topical treatments, gabapentinoids, opioids and alternative medicine. We also review the available data on CKD-aP treatments in development and propose new guidelines for managing patients with CKD-aP.

Western and complementary alternative medicine treatment of uremic pruritus: A literature review

Uremic pruritus (UP), also called chronic kidney disease-associated pruritus (CKD-aP), is a bothersome symptom that causes sleep disturbance, anxiety, depression, and reduced quality of life. Pruritus often occurs in patients with end-stage renal disease. There is still no definite treatment for UP due to its unclear pathogenesis. We searched electronic databases (PubMed and Google Scholar) and gathered the latest clinical trials and pilot studies of Western and complementary alternative medicine (CAM) therapies for UP in English. These UP studies were separated into three main groups: systemic, topical, and others and CAM. Gabapentin, nalfurafine, acupuncture, and Chinese herbal bath therapy (CHBT) show antipruritic effects, with higher evidence grades in the meta-analysis. Emollients with additive compounds are more effective for reducing itch than emollients without additives. Supplements for deficient elements, such as zinc, omega-3, and omega-6, also show benefits for pruritus improvement. CAM therapies such as acupuncture, herbs, and herbal baths or creams all have good results for UP treatment. We summarize the treatments and suggest a treatment algorithm for UP according to severity. Some UP therapies are already supported by large-scale clinical evidence, and some new treatments can provide patients with new hope and treatment options. However, these new methods still need large population studies and further exploration.

Chronic Kidney Disease-Associated Pruritus: A Review

BACKGROUND

Chronic kidney disease-associated pruritus (CKD-aP), also known as uraemic pruritus, is a disabling symptom for patients and a challenging condition for clinicians. Despite being common amongst end-stage kidney disease (ESKD) patients, it remains underestimated and underdiagnosed. The exact pathogenesis remains largely elusive, which hampers the synthesis of a definite treatment approach.

SUMMARY

Chronic pruritus (lasting 6 weeks or more in duration) is a common and potentially disabling symptom in patients with advanced CKD. A unified hypothesis of pathogenesis has not yet been concluded. Studies have shown changes in the immunochemical milieu of the skin in patients with CKD-aP with several inciting stimuli identified. However, other unrecognized factors are likely to be involved. This article will review the current observations and understanding of the postulated pathogenesis of CKD-aP, as well as the evidence for current management strategies. Key Messages: CKD-aP is a common and troubling symptom amongst ESKD patients that is associated with decreased quality of life and poor prognosis. Its exact pathogenesis, at the time of writing, is not well-understood. A stepwise approach is recommended for management. Systematic reviews show the largest body of evidence was found for the effectiveness of gabapentin. Comparison is needed between newly emerging pharmacological agents such as kappa-opioid receptor agonists and more established agents, such as the gabapentinoids. Finally, renal transplantation should be considered in severe and refractory cases who are suitable transplant candidates as it has shown an excellent outcome in most cases.

2020 guidelines for the diagnosis and treatment of cutaneous pruritus

The mechanisms underlying itch are not fully understood. Physicians usually encounter difficulty controlling itch in generalized pruritus. Since only a small percentage of patients with generalized pruritus respond to antihistamines (H₁ receptor antagonists), a variety of itch mediators and mechanisms other than histaminergic signals are considered to be involved in itch for these non-responsive patients. In 2012, we created guidelines for generalized pruritus. Those guidelines have been updated and revised to make some of the definitions, diagnostic terms, and classifications more applicable to daily clinical practice. Cutaneous pruritus as designated in these guidelines is a disease characterized by itch without an observable rash. Generalized pruritus (without skin inflammation) is defined as the presence of itch over a wide area, and not localized to a specific part of the body. This entity includes idiopathic pruritus, pruritus in the elderly, symptomatic pruritus, pregnancy-associated pruritus, drug-induced pruritus, and psychogenic pruritus. Localized pruritus (without skin inflammation) represents fixed itch localized to a specific part of the body, and includes anogenital pruritus, scalp pruritus, notalgia paresthetica, and brachioradial pruritus. These guidelines outline the current concepts and specify the diagnostic methods/treatments for cutaneous pruritus.

Chronic Kidney Disease-Associated Itch (CKD-aI) in Children-A Narrative Review

Chronic kidney disease (CKD) is a condition of widespread epidemiology and serious consequences affecting all organs of the organism and associated with significant mortality. The knowledge on CKD is rapidly evolving, especially concerning adults. Recently, more data is also appearing regarding CKD in children. Chronic itch (CI) is a common symptom appearing due to various underlying dermatological and systemic conditions. CI may also appear in association with CKD and is termed chronic kidney disease-associated itch (CKD-aI). CKD-aI is relatively well-described in the literature concerning adults, yet it also affects children. Unfortunately, the data on paediatric CKD-aI is particularly scarce. This narrative review aims to describe various aspects of CKD-aI with an emphasis on children, based on the available data in this population and the data extrapolated from adults. Its pathogenesis is described in details, focusing on the growing role of uraemic toxins (UTs), as well as immune dysfunction, altered opioid transmission, infectious agents, xerosis, neuropathy and dialysis-associated aspects. Moreover, epidemiological and clinical aspects are reviewed based on the few data on CKD-aI in children, whereas treatment recommendations are proposed as well, based on the literature on CKD-aI in adults and own experience in managing CI in children.

Self-reported Pruritus and Clinical, Dialysis-Related, and Patient-Reported Outcomes in Hemodialysis Patients

RATIONALE & OBJECTIVE

Chronic kidney disease (CKD)-associated pruritus, generalized itching related to CKD, affects many aspects of hemodialysis patients' lives. However, information regarding the relationship between pruritus and several key outcomes in hemodialysis patients remains limited.

STUDY DESIGN

Prospective cohort.

SETTING & PARTICIPANTS

23,264 hemodialysis patients from 21 countries in the Dialysis Outcomes and Practice Patterns Study (DOPPS) phases 4 to 6 (2009-2018).

EXPOSURE

Pruritus severity, based on self-reported degree to which patients were bothered by itchy skin (5-category ordinal scale from "not at all" to "extremely").

OUTCOMES

Clinical, dialysis-related, and patient-reported outcomes.

ANALYTICAL APPROACH

Cox regression for time-to-event outcomes and modified Poisson regression for binary outcomes, adjusted for potential confounders.

RESULTS

The proportion of patients at least moderately bothered by pruritus was 37%, and 7% were extremely bothered. Compared with the reference group ("not at all"), the adjusted mortality HR for patients extremely bothered by pruritus was 1.24 (95% CI, 1.08-1.41). Rates of cardiovascular and infection-related deaths and hospitalizations were also higher for patients extremely versus not at all bothered by pruritus (HR range, 1.17-1.44). Patients extremely bothered by pruritus were also more likely to withdraw from dialysis and miss hemodialysis sessions and were less likely to be employed. Strong monotonic associations were observed between pruritus severity and longer recovery time from a hemodialysis session, lower physical and mental quality of life, increased depressive symptoms, and poorer sleep quality.

LIMITATIONS

Residual confounding, recall bias, nonresponse bias.

CONCLUSIONS

Our findings demonstrate how diverse and far-reaching poor outcomes are for patients who experience CKD-associated pruritus, specifically those with more severe pruritus. There is need for change in practice patterns internationally to effectively identify and treat patients with pruritus to reduce symptom burden and improve quality of life and possibly even survival.

Interventions for itch in people with advanced chronic kidney disease

BACKGROUND

Itch in patients with chronic kidney disease (CKD) is common, often very distressing and associated with depression, reduced quality of life, and increased death. The most common first-line treatment has been the use of antihistamines despite the lack of substantial evidence for its use for uraemic itch. Few recommendations and guidelines exist for treatment.

OBJECTIVES

We aimed to determine: 1) the benefits and harms (both absolute and relative) of all topical and systemic interventions for the treatment of uraemic itch, either alone or in combination, when compared with placebo or standard care; and, 2) the dose strength or frequency, stage of kidney disease or method of dialysis used (where applicable) in cases where the effects of these interventions vary depending on co-interventions.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 17 December 2019 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in adults with CKD stages 4 or 5 comparing treatments (pharmacological, topical, exposure, dialysis modality) for CKD associated itch to either placebo or other established treatments.

DATA COLLECTION AND ANALYSIS

Two authors independently abstracted study data and assessed study quality. Data were analysed using a random effects meta-analysis design estimating the relative effects of treatment versus placebo. Estimates of the relative effects between treatments are included where possible. For continuous measures of severity of itch up to three months, mean difference (MD) or standardised mean difference (SMD) were used. When reported, adverse effects were tabulated. The certainty of the evidence was estimated using GRADE.

MAIN RESULTS

Ninety-two RCTs, randomising 4466 participants were included. Fifty-eight studies (3285 participants) provided sufficient data to be meta-analysed. Of these, 30 compared an intervention to a placebo or control. The 10 cm Visual Analogue Scale (VAS) was the dominant instrument utilized for itch reporting and the Duo score was used in a minority of studies. GABA analogues including, gabapentin and pregabalin, reduce itch in patients with CKD (5 studies, 297 participants: 4.95 cm reduction, 95% CI 5.46 to 4.44 lower in VAS compared to placebo; high certainty evidence). Kappa opioid agonists, including nalfurafine also reduced itch in this population (6 studies, 661 participants: 1.05 cm reduction, 95% CI 1.40 to 0.71 lower in VAS compared to placebo; high certainty evidence). Ondansetron had little or no effect on itch scores (3 studies, 183 participants: 0.38 cm reduction, 95% CI 1.04 lower to 0.29 higher in VAS compared to placebo; high certainty evidence). Reduction in the severity of itch was reported with oral montelukast, turmeric, zinc sulfate and topical capsaicin. For all other interventions, the certainty of the evidence was low to moderate, and the interventions had uncertain effects on uraemic pruritus. Six studies have disclosed significant financial support from their respective manufacturers, six were affected by lack of blinding, and 11 studies have 15 participants or less. Older, smaller RCTs often failed to follow intention-to-treat protocols with unexplained dropouts after randomisation. Adverse effects were generally poorly and inconsistently reported across all RCTs. No severe adverse events were reported for any intervention.

AUTHORS' CONCLUSIONS

The RCTs of this meta-analysis contain a large array of interventions with a diverse set of comparators. For many interventions, trials are sparse. This served to make informative meta-analysis challenging. Of all treatments for uraemic pruritus, gabapentinoids (gabapentin and pregabalin) were the most studied and show the greatest reduction in itch scores. Further RCTs, even of the scale of the largest trials included in this review, are unlikely to significantly change this finding. Kappa-opioid agonists (mainly nalfurafine) also may reduce itch, but indirect comparison suggests a much more modest effect in comparison to GABA analogues. Evidence for oral montelukast, turmeric, zinc sulfate, and topical capsaicin also showed an itch score reduction. However, these reductions were reported in small studies, and warrant further investigation. Ondansetron did not reduce itch. It is somewhat unlikely that a further study of ondansetron will change this result.

Efficacy of uremic pruritus treatment in patients undergoing hemodialysis, a network meta-analysis for randomized clinical trials

INTRODUCTION

Uremic pruritus is very common in hemodialysis or renal failure patients, there were lots of available treatments such as gabapentin, pregabalin, ondansetron, etc. However, there is no quantified study comparing these treatments together, it is impossible to conduct a clinical trial involving so many treatments, so we conduct a network meta-analysis to compare them.

METHOD

We collected mean difference and standard error of visual analogue scale data as outcome. In total we collected 15 articles, 15 articles, 1180 subjects and 6 treatments included to this study.

RESULTS

In these comparisons, gabapentin showed the largest effect MD: 5.19, 95%CI [3.77, 6.61], anti-histamine MD: 4.65, 95%CI [2.22, 7.07] and pregabalin MD: 4.62, 95%CI [2.71, 6.62] showed a similar effect. Opioid pathway related treatment also showed a significant but not so large effect MD: 2.45, 95%CI [0.41, 4.49]. Ondansetron and Doxepin didn't show a significant improvement among placebo, the overall quantifying heterogeneity I²=43.1%. There is no statically difference between gabapentin, pregabalin and anti-histamine treatments.

CONCLUSIONS

So we conclude that gabapentin, pregabalin and anti-histamine has a similar efficacy on pruritus control.

Have We Just Scratched the Surface? A Narrative Review of Uremic Pruritus in 2020

Purpose of review:

Uremic pruritus is a highly prevalent and debilitating symptom in patients with chronic kidney disease (CKD) and end-stage kidney disease (ESKD). The purpose of this review is to examine current evidence on the mechanisms and treatments of pruritus in CKD and highlight promising areas for future research.

Sources of information:

Published literature, including randomized controlled trials, cohort studies, case reports, and review articles, was searched for evidence pertaining to the pathophysiology and treatment of uremic pruritus.

Methods:

A comprehensive narrative review was conducted to explore the molecular mechanisms underlying uremic pruritus, as well as the evidence (or lack thereof) supporting pharmacological and nonpharmacological treatments for uremic pruritus. The potential role of patient sex in the pathophysiology and management of uremic pruritus is also discussed.

Key findings:

The pathophysiology of uremic pruritus involves a complex interplay of uremic toxins, systemic inflammation, mast cell activation, and imbalance of opioid receptors. Classic treatment strategies for uremic pruritus include optimization of dialysis parameters, amelioration of CKD-related mineral and bone disease, topical emollients and analgesics, antihistamines, the anticonvulsant medications gabapentin and pregabalin, and ultraviolet light B (UV-B) phototherapy. Strong data to support many of these classical treatments for uremic pruritus are limited. Newly evolving treatment approaches for uremic pruritus include opioid receptor modulators, neurokinin-1 inhibitors, and cannabinoids. Further studies regarding their efficacy, pharmacodynamics, and safety in the CKD and ESKD population are needed before these agents are accepted into widespread use. Additional nonpharmacological strategies aimed at treating uremic pruritus include psychotherapy, acupuncture, omega-3 fatty acids, and exercise. Finally, sex differences may exist regarding uremic pruritus, but studies directly addressing sex-specific mechanisms of uremic pruritus remain absent.

Limitations:

High-quality evidence in the management of uremic pruritus remains lacking. Most recommendations are based on expert opinion or studies involving small numbers of patients. In addition, our understanding of the pathophysiological mechanisms behind uremic pruritus is incomplete and continues to evolve over time.

Implications:

Uremic pruritus is a common symptom which reduces quality of life in CKD and ESKD. The identification of novel targeted treatment approaches may ease the burden of uremic pruritus in the future.

Cannabis Use for Restless Legs Syndrome and Uremic Pruritus in in patients treated with maintenance dialysis: A Survey

Background:

Restless legs syndrome (RLS) and uremic pruritus reduce the quality of life in patients with end-stage kidney disease (ESKD) and current treatments are often insufficient. There is an increasing interest in using cannabinoids for symptom management, and preliminary evidence suggests cannabinoids may help alleviate RLS and pruritus.

Objectives:

(1) To assess the frequency and severity of RLS and pruritus in our ESKD population with the current treatment options, (2) to estimate patient use of cannabinoids for these symptoms, and (3) to determine interest in participating in future trials to treat RLS and/or pruritus.

Design:

Survey.

Patients:

Adult prevalent patients with ESKD treated with dialysis at the Ottawa Hospital.

Measurements:

International RLS Study Group Rating Scale and visual analogue scale for symptom severity of RLS and pruritus, respectively.

Methods:

Eligible patients with ESKD treated at the Ottawa Hospital were invited to complete a survey to identify symptoms and severity of RLS and pruritus using validated scales, cannabis use for management, and interest in future trials. Basic demographic statistics to describe the study population and results were used.

Results:

Sixty-nine percent (192 of 277) of eligible patients completed the surveys, 35 declined participation, and 50 surveys were not returned. Eighty-six (45%) and 129 patients (67%) reported symptoms of RLS and pruritus, respectively. Only 18 previously symptomatic patients were relieved with current treatment. Fifteen patients reported cannabis use for symptoms; 9 noted improvement. Most (>2 of 3) symptomatic patients were interested in participating in a future trial.

Limitations:

Single-center study in a tertiary-care hospital in Canada limiting generalizability. Quoted prevalence of symptoms is dependent on survey return.

Conclusions:

A large proportion of ESKD patients suffer from RLS and/or pruritus, most of which are not relieved by existing treatments. Few patients reported trying cannabis to decrease their symptoms despite legalization. This study confirms strong patient interest for future trials regarding cannabis for symptom relief.

Trial Registration:

Not applicable.

Comparison of gabapentin and hydroxyzine in the treatment of pruritus in patients on dialysis

BACKGROUND

Pruritus is one of the most common problems in patients with chronic renal failure. Of all patients with end-stage renal disease (ESRD), 60-80% report pruritus during their life.

AIM

To compare the effect of gabapentin (GBP) and hydroxyzine (HYDZ) in treating pruritus in patients on dialysis.

METHODS

In a double-blind, randomized, crossover clinical trial, 32 patients on dialysis who reported pruritus were assigned randomly to receive either GBP or HYDZ for 6 weeks; the first group received GBP 100 mg/day orally and the second group received HYDZ 25 mg/day orally for 6 weeks. After this 6-week period (Period 1) there was a washout period of 2 weeks then patients were crossed over to the other drug (the first group receiving HYDZ and second group receiving GBP) and followed up for a further 6 weeks (Period 2). A visual analogue scale was used to measure pruritus intensity in the groups before and after the first and second period.

RESULTS

In Period 1, pruritus severity decreased from 7.1 ± 1.46 at baseline to 2.17 ± 1.82 at 6 weeks in the GBP group (P = 0.001) and from 6.83 ± 2.11 to 2.86 ± 1.67 in the HYDZ group (P = 0.001). In Period 2, pruritus severity decreased from 5.1 ± 1.61 at baseline to 1.56 ± 0.82 at 6 weeks in the GBP group (P < 0.01) and from 5.23 ± 2.11 to 2.1 ± 1.87 in the HYDZ group (P = 0.001).

CONCLUSION

Results showed that both HYDZ and GBP significantly improved and controlled pruritus in patients on dialysis, with no significant difference observed between the two drugs.

Current and emerging systemic treatments targeting the neural system for chronic pruritus

INTRODUCTION

Pruritus is a debilitating symptom that significantly affects the quality of life of patients who suffer from it. Many current and emerging systemic treatments targeting the neural system have been successful in treating itch of various underlying etiologies.

AREAS COVERED

A complete search of the PUBMED and Google Scholar databases was completed and literature pertinent to current and emerging systemic anti-pruritic drugs which target the neural system was compiled. The purpose of this review is to give the reader with an overview of the current and emerging systemic therapeutic options which target the neural system for chronic pruritus. The authors then provide the reader with their expert perspectives on the future of these therapies.

EXPERT OPINION

Exciting new anti-pruritic therapies targeting the neural system which show promise include NK-1 inhibitors, opioid receptor modulators, and drugs targeting specific itch receptors such as Mrgpr, Na_v1.7, and PAR2, as well as selective GABA modulators. Future studies should be conducted in order to fully understand these exciting therapeutic options.

CKD-Associated Pruritus: New Insights Into Diagnosis, Pathogenesis, and Management

Chronic kidney disease–associated pruritus (CKD-aP) is a common, troubling and in some cases debilitating problem for patients with CKD and end-stage renal disease. Despite a prevalence rate of approximately 20% in CKD and 40% in end-stage renal disease, and a clear association with poorer psychosocial and medical outcomes, this condition is often underreported by patients and overlooked by health care providers. This is likely due, in part, to uncertainty regarding its pathogenesis and treatment. Most commonly, CKD-aP is attributed to toxin build-up, peripheral neuropathy, immune system dysregulation, or opioid dysregulation. Prior treatment studies of CKD-aP have targeted these potential etiologies but have been limited by noncontrolled design, small sample size, and non-uniform definitions of CKD-aP. Recently, several large, randomized controlled trials targeting opioid dysregulation have yielded promising results. These trials have spurred new hope for understanding and treating this condition.

Effect of mirtazapine on pruritus in patients on hemodialysis: a cross-over pilot study

BACKGROUND

Uremic pruritus (UP) is a highly prevalent and disturbing problem in patients with advanced chronic kidney disease (CKD); however, treatment of UP is largely unsatisfactory. The present study was designed to investigate the effectiveness of mirtazapine, an atypical antidepressant agent with potent antagonistic activity against serotonin (5HT2, 5HT3) and histamine (H1) receptors, in the treatment of pruritus in hemodialysis (HD) patients.

METHODS

An 8-week long, prospective, open-label, and cross-over randomized clinical trial study was conducted on 77 HD patients with chronic pruritus. After a 2-week washout period, eligible patients were randomly assigned either to the mirtazapine (15 mg per day) or gabapentin (100 per day) for 2 weeks. Following 2 weeks washout period, subjects crossed over to the other treatment arm for 2 more weeks. The severity of pruritus was measured seven times during each treatment period using the visual analogue scale (VAS). Furthermore, at the end of the study, patients also were blindly asked which treatment (first or last in the sequential course of the study) they preferred.

RESULTS

Sixty-one patients completed two treatment periods of the study. Although, compared to baseline, both gabapentin and mirtazapine treatment resulting in significant improvement in VAS scores, decreasing in pruritus severity was significantly greater in the mirtazapine treatment period compared with the gabapentin treatment period (P < 0.001). Furthermore, although side effects such as drowsiness and dry mouth more reported in the mirtazapine treatment period, overall higher percentage of the study patients preferred mirtazapine over gabapentin for the treatment of their pruritus symptoms.

CONCLUSIONS

Although preliminary, our study provides evidence that mirtazapine can be an effective therapy for UP in patients who are on maintenance HD. However, further studies would be necessary to confirm effectiveness as well as the safety of mirtazapine in the long-term management of chronic pruritus.

Itching as the onset of pain (part 2)

Itching of the skin is a particularly unpleasant subjective sensation that causes the need to scratch. Physiological itching occurs in response to environmental irritants (friction, insect crawling, temperature changes, etc.) and disappears after elimination of the cause. Pathological itching is caused by changes in the skin or throughout the body and causes a strong need to get rid of itching by combing or any other method. Itching is a common symptom of local (dermatological) or general (systemic) disease. It can be limited (localized) or diffuse (generalized).One of the causes of itching is often noted endocrine diseases and metabolic disorders: hyper- and hypofunction of the thyroid gland, diabetes mellitus and hyperparathyroidism. In thyroid hyperfunction, generalized (inconstant and little-pronounced) itching of the skin is observed in the clinical picture only in 10 % of patients. It is accepted that itching of the skin in thyrotoxicosis syndrome is due to increased activity of kinin in combination with an increase in major metabolism and an increase in body and skin temperature (123).Itching caused by impaired bile secretion is characteristic of many diseases of the liver: primary biliary cirrhosis, sclerosing cholangitis, viral hepatitis caused by cholestasis medications and other causes of obstructive jaundice. It is in these cases that prurigo is usually generalized, but in some typical cases it is more pronounced on the feet and palms. With this pathology, itching is caused by obstruction of the biliary tract, however, and to this day, no close correlation has been found between serum bilirubin and the severity of itching.If it was previously thought that itching in pathology of the peripheral or central nervous system, such as multiple sclerosis, neuropathy, compression or irritation of nerves (e.g., paraesthetic dorsalgia, brachioradial itching) is also a significant symptom, then modern studies prove that in more cases, itching is not characteristic of most pathologies of the nervous system, so after a detailed anamnesis, examination and initial research, the patient should be referred to a related specialist, except in cases of about obvious postherpetic neuropathy, painless paresthesia, or brachioradial itching, which can often be guided in the provision of primary care.Instead, there are some psychological conditions and a number of psychiatric illnesses (obsessive-compulsive disorders, depression, and parasite illusions) that are most commonly diagnosed with the exclusion method. Neurotic squabbles are scattered on the body of the excorii, covered with scales that may occur in any area of the body that the patient may reach, but are often limited by limbs.

Development and Validation of a Uremic Pruritus Treatment Algorithm and Patient Information Toolkit in Patients With Chronic Kidney Disease and End Stage Kidney Disease

CONTEXT

Uremic pruritus (UP) affects up to half of all patients with kidney disease and has been independently associated with poor patient outcomes. UP is a challenging symptom for clinicians to manage as there are no validated guidelines for its treatment.

OBJECTIVES

The study aimed to develop and validate an algorithm and patient information toolkit for the treatment of UP in patients with kidney disease.

METHODS

The study involved a literature search and development of an initial draft algorithm, followed by content and face validation of this algorithm. Validation entailed three rounds of interviews with six nephrology clinicians per round. Participants assessed the relevance of each component of the algorithm and then rated a series of statements on a scale of 1-5 to assess face validity of the algorithm. After each round, the content validity index (CVI) of each algorithm component was calculated, and the algorithm was revised by the study team in response to findings. This process was followed by a second study that developed and validated a patient information pamphlet and video.

RESULTS

Algorithm validation participants were affiliated with three institutions and included seven physicians, four registered nurses, three nurse practitioners, three pharmacists, and a dietician. The average CVI of the algorithm components across all three rounds was 0.89, with 0.80 commonly cited as the lower acceptable limit for content validation. More than 78% of participants rated each face validity statement as "Agree" or "Strongly Agree". For the patient information tools, five clinicians and 15 patients were included in validation. The average CVI was 1.00 for both tools, and the average face validity was 92%.

CONCLUSION

A treatment algorithm and patient information toolkit for managing UP in patients with kidney disease were developed and validated through expert review. Further research will be conducted on implementation of the treatment algorithm and evaluating patient-reported outcomes.

Safety and efficacy of PG102P for the control of pruritus in patients undergoing hemodialysis (SNUG trial): study protocol for a randomized controlled trial

BACKGROUND

Pruritus in patients undergoing hemodialysis is a highly prevalent complication that affects quality of life. Several medications are currently used for the treatment of uremic pruritus, but these are not satisfactory. PG102P, which is prepared from Actinidia arguta, has an immune-modulating effect on pruritus. This trial is designed to assess the antipruritic effect of PG102P compared with placebo.

METHODS

This multicenter, randomized, double-blind, placebo-controlled clinical trial will include 80 patients undergoing hemodialysis. The patients will be randomized in a 1:1 ratio to a treatment group (PG102P 1.5 g/day) or a control group (placebo). The treatment will last for 8 weeks, followed by a 2-week observational period. During the observational period, all of the patients will maintain the antipruritic treatment previously used. The primary endpoint will be measured as the difference in visual analog scale between the groups before and after treatment. Secondary outcomes include serum levels of total immunoglobulin E, eosinophil cationic protein, potassium, calcium, phosphorus, intact parathyroid hormone, and blood eosinophil count between weeks 0 and 8. Kidney Disease and Quality of Life and Beck's Depression Inventory questionnaires will be conducted. Safety assessments and any adverse events that occur will also be evaluated.

DISCUSSION

The SNUG is a clinical study that aims to investigate the antipruritic effect of PG102P to ameliorate itching in patients undergoing hemodialysis.

TRIAL REGISTRATION

Clinical Trials.gov, NCT03576235. Registered on 4 July 2018.

[Pruritus in systemic diseases : Common and rare etiologies]

Chronic pruritus is a symptom of various internal disorders. In contrast to dermatological diseases, pruritus does not present with primary skin alterations in these patients. However, intense scratching my cause secondary skin changes such as abrasion, excoriation, prurigo nodularis, or in rare cases even scarring. The most common internal causes for chronic pruritus are chronic kidney disease, hepatobiliary, and hematological disorders as well as adverse drug reactions. Pruritus is less commonly seen in patients with endocrine or metabolic diseases, malabsorption syndromes, infectious diseases, and solid tumors. The pathogenesis of pruritus in these disorders remains largely elusive, albeit first insights have been gained for uremic and cholestatic pruritus. Antipruritic treatment is therefore symptomatic in most cases and may represent a clinical challenge. The calcium channel blockers gabapentin and pregabalin have the best proven efficacy in chronic kidney disease associated pruritus. In Japan, nalfurafine, a κ-opioid receptor agonist, has been licensed for this indication. UVB light may also attenuate uremic symptoms. In patients suffering from hepatobiliary disorders the sequestrant cholestyramine and the enzyme inducer rifampicin are effective. Furthermore, bezafibrate, the μ‑opioid receptor antagonists and, in Japan, nalfurafine may be used to ameliorate cholestatic pruritus. So far, no randomized controlled trials have been performed for chronic itch in other internal disorders. Antipruritic treatment is symptom-based with a focus on the effective therapy of the underlying disease.

The association between CKD-associated pruritus and quality of life in patients undergoing hemodialysis in Pakistan: A STROBE complaint cross-sectional study

Chronic kidney disease (CKD)-associated pruritus is one of the most common symptoms found in patients who undergo dialysis for CKD, leading to a compromised quality of life. This study aimed to investigate the association between CKD-associated pruritus and the quality of life in patients undergoing hemodialysis in Pakistan.A cross-sectional multicenter study was carried out from July 2016 to April 2017 in 2 tertiary care hospitals in Pakistan. Patients aged 18 years and above of both genders, undergoing hemodialysis, understood the Urdu language, and were willing to participate; were included.Of 354 recruited patients with a response rate of 100%, majority (66.1%) of the patients were males. The median (intra-quartile range [IQR]) age of patients was 42.0 [34.0-50.0] years. The prevalence of pruritus was 74%. The median [IQR] score for pruritus was 10.0 (out of possible 25) [8.0-12.0]. Multivariate linear regression revealed a statistically significant association between CKD-associated pruritus with age of patients (β = 0.031; 95% confidence interval [CI] = 0.002-0.061; P = .038), duration of CKD (β = -0.013; 95% CI = -0.023 --0.003; P = .014) and quality of life (β= -0.949; 95% CI = -1.450; -0.449). The median [IQR] score for health-related quality of life was 52.00 [43.00-58.00].Prevalence of CKD-associated pruritus was reported to be 74% and it negatively affected the patient's quality of life. Patients with moderate to severe CKD-associated pruritus have poor quality of life. With an increase in intensity of pruritus, the QOL score decreased among the patients undergoing hemodialysis.

Chronic Kidney Disease-Associated Pruritus and Quality of Life in Malaysian Patients Undergoing Hemodialysis

CKD-associated pruritus is one of the common symptoms in patients undergoing dialysis, thus contributing to the diminished and compromised quality of life. This study aimed to explore the association between the CKD-associated pruritus on quality of life of patients undergoing hemodialysis in Malaysia. A cross-sectional multicenter study, carried out from February to September 2017 at tertiary care settings in Kuala Lumpur, Malaysia. Patients aged 18 years and above, undergoing hemodialysis, understanding Malay language and willing to participate were included. The CKD-associated pruritus was assessed by using Malay 5D-itch scale and Malay FANLTC questionaiare. To determine the factors associated with pruritus and quality of life, multivariate logistic regression analysis was used having P value < 0.05 as statistically significant. Among n = 334 recruited patients with a response rate of 100%, 59.6% were males and total of 61.3% were having CKD-associated pruritus. The results showed a statistically significant weak negative correlation between CKD-associated pruritus and quality of life. Multivariate linear regression revealed none of these factors were found to be associated with pruritus; however, CKD-associated prurtius was found to be associated with quality of life score. CKD-associated pruritus is have a negative impact on the patient's quality of life including physical, social, mental/emotional, and functional well-being. Despite the high prevalence and negative impact of CKD-associated pruritus on quality of life, it is disregarded by most health care professionals. It is thus pertinent to monitor the potential risk factors and consider providing timely treatment implications for CKD-associated pruritus in hemodialysis patients, in order to improve their quality of life.

Can we use psychoactive drugs to treat pruritus?

Pruritus is a frequent complaint both in dermatology and general medicine. This burdensome symptom has a complex and multifactorial pathogenesis, with the key involvement of central nervous system in its development. Psychoactive drugs (psychopharmaceuticals) encompass several therapeutic groups utilized mainly in psychiatry. However, these drugs are occasionally used in dermatological practice and may contribute to alleviation of pruritus in a variety of cutaneous and extracutaneous disorders. This review article summarizes the role of H1-antihistamines, antidepressants, antipsychotics and antiepileptics in managing pruritus.

Prospective, double-blind, randomized clinical trial comparing an ERAS pathway with ketorolac and pregabalin versus standard of care plus placebo during live donor nephrectomy for kidney transplant

Opioid exposure is a concern after live donation for kidney transplant. We theorized that an enhanced recovery after surgery pathway (ERAS) using pregabalin preoperatively to desensitize nerves followed by the nonsteroidal anti-inflammatory drug ketorolac, during and after surgery, can control pain, thus requiring less perioperative narcotics. The aim of this study was to determine if the use of a nonopioid analgesic ERAS protocol for donor nephrectomies could decrease the use of narcotics without an increase in complications compared with standard of care (SOC). This is a single-center, prospective, double-blind, randomized clinical trial involving a total of 62 patients undergoing nephrectomy for live donor kidney transplant. Length of hospital stay (LOS) was significantly reduced by 10% in the ERAS group versus the SOC-plus-placebo group. Morphine dose equivalents were significantly reduced by 40% in the study group versus the SOC-plus-placebo group. The use of this nonopioid analgesic ERAS pathway for donor nephrectomies decreased the use of narcotics without an increase in complications compared with SOC. There was significantly reduced LOS and less narcotic use in the study group versus the SOC-plus-placebo group. (ClinicalTrials.gov registration number: NCT03669081).

Treatments of uremic pruritus: A systematic review

Till now many treatments attempted to relieve uremic pruritus (UP) though none of them are definite treatment. In this study, we gathered all studies conducted on UP treatment since 2000-2016. We conducted a systematic review by searching the electronic databases (PubMed, Scopus, and Google scholar). Patients were with chronic kidney disease who complained of UP. Clinical trials and pilot studies in English and Persian which were done on patients with ESRD who complained of itching between 2000 till 2016 were gathered. A total of 166 articles were collected. After excluding articles 41 articles were remaining. Then UP treatments classified into two main groups: Medical (chemical and herbal medicine) and non-medical. Most studies measured UP by VAS scoring system in which patients described the severity. This scoring system is individual dependent. There are lots of studies on UP treatment though there are lots of controversies in studies. Finding a definite cure for this unpleasant symptom can improve patients' quality of life. Conducting further studies for each treatment on larger population is essential to improve quality of life among the end stage renal disease patients.

Gabapentin and Pregabalin Use and Association with Adverse Outcomes among Hemodialysis Patients

Background Gabapentin and pregabalin are used to manage neuropathic pain, pruritus, and restless legs syndrome in patients on hemodialysis. These patients may be especially predisposed to complications related to these agents, which are renally cleared, but data regarding the risk thereof are lacking.Methods From the US Renal Data System, we identified 140,899 Medicare-covered adults receiving hemodialysis with Part D coverage in 2011. Using Cox regression models in which we adjusted for demographics, comorbidities, duration of exposure, number of medications, and use of potentially confounding concomitant medications, we investigated the association between gabapentin and pregabalin, modeled as separate time-varying exposures, and time to first emergency room visit or hospitalization for altered mental status, fall, and fracture. We evaluated risk according to daily dose categories: gabapentin (>0-100, >100-200, >200-300, and >300 mg) and pregabalin (>0-100 and >100 mg).Results In 2011, 19% and 4% of patients received gabapentin and pregabalin, respectively. Sixty-eight percent of gabapentin or pregabalin users had a diagnosis of neuropathic pain, pruritus, or restless legs syndrome. Gabapentin was associated with 50%, 55%, and 38% higher hazards of altered mental status, fall, and fracture, respectively, in the highest dose category, but even lower dosing was associated with a higher hazard of altered mental status (31%-41%) and fall (26%-30%). Pregabalin was associated with up to 51% and 68% higher hazards of altered mental status and fall, respectively.Conclusions Gabapentin and pregabalin should be used judiciously in patients on hemodialysis, and research to identify the most optimal dosing is warranted.

Effect of extended hours dialysis on sleep quality in a randomized trial

AIM

Poor sleep quality is common in haemodialysis patients and associated with worse outcomes. In this pre-specified analysis, we examined the impact of extended hours haemodialysis on sleep quality.

METHODS

The ACTIVE Dialysis trial randomized 200 participants to extended (≥24 h/week) or standard (target 12-15 h) hours haemodialysis over 12 months. Sleep quality was measured in the Kidney Disease Quality of Life Short Form 1.3 (KDQOL-SF) by overall sleep quality score (0-10, 10 = 'very good') and the sleep subscale (0-100, 100 = 'best possible sleep') every 3 months via blinded telephone interview. The average intervention effect was calculated by mixed linear regression adjusted by time point and baseline score. Factors predicting sleep quality were assessed by multivariate regression analysis.

RESULTS

Overall sleep quality score and sleep subscale at baseline were similar in both groups (5.9 [95%CI 5.4-6.4] vs. 6.3 [5.9-6.8]; 65.0 [60.9-69.1] vs. 63.2 [59.1-67.3]; extended and standard hours, respectively). Extended hours haemodialysis led to a non-significant improvement in overall sleep quality score (average intervention effect 0.44 (-0.01 to 0.89), P = 0.053) and sleep subscale (average intervention effect 3.58 (-0.02 to 7.18), P = 0.051). Poor sleep quality was associated with being female and with current smoking. Sleep quality was positively associated with EuroQol-5D (EQ5D) and the SF-36 Physical Component and Mental Component Summary Scores but not with hospitalizations.

CONCLUSION

Sleep quality was not significantly improved by extended hours dialysis in this study. Sleep quality is positively correlated with quality of life in haemodialysis patients and is poorer in women and current smokers.

The vicious cycle of itch and anxiety

Chronic itch is associated with increased stress, anxiety, and other mood disorders. In turn, stress and anxiety exacerbate itch, leading to a vicious cycle that affects patient behavior (scratching) and worsens disease prognosis and quality of life. This cycle persists across chronic itch conditions of different etiologies and even to some extent in healthy individuals, suggesting that the final common pathway for itch processing (the central nervous system) plays a major role in the relationship between itch and anxiety. Pharmacological and nonpharmacological treatments that reduce anxiety have shown promising anti-itch effects. Further research is needed to establish specific central mechanisms of the itch-anxiety cycle and provide new targets for treatment.

International Comparisons of Prevalence, Awareness, and Treatment of Pruritus in People on Hemodialysis

BACKGROUND AND OBJECTIVES

Uremic pruritus in patients on hemodialysis is associated with depression, lower quality of life, and mortality. We studied the prevalence, awareness, and treatment of pruritus to assess how well this important condition is currently managed internationally.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Data from 35,452 patients on hemodialysis in up to 17 countries from the Dialysis Outcomes and Practice Patterns Study were analyzed to describe pruritus prevalence from 1996 to 2015. Data from 6256 patients and 268 medical directors in 17 countries in 2012-2015 were analyzed to describe predictors, effects, medical directors' awareness, and treatment of pruritus.

RESULTS

Patients very much or extremely bothered by itching declined from 28% in 1996 to 18% in 2015. In 2012-2015, among patients nearly always or always bothered by itching, pruritus had a major effect on work and social life; 18% used no treatment for pruritus, and 17% did not report itching to health care staff. In total, 69% of medical directors underestimated the prevalence of pruritus in their unit. Managing high serum phosphorus and low Kt/V was ranked as the most important intervention, but no relationship was found between these factors and pruritus; 57% of medical directors used oral antihistamines for first-line chronic treatment of pruritus. Gabapentin was used by 45% as first-, second-, or third-line treatment. Nalfurafine was only used in Japan.

CONCLUSIONS

The prevalence of pruritus in people on hemodialysis is decreasing but remains underestimated. Large numbers of patients on hemodialysis with severe pruritus do not receive treatment. There is wide variation in the use of unlicensed medications for the treatment of pruritus. These data provide a benchmark for initiatives to improve the management of uremic pruritus.

MULTIMEDIA

This article contains multimedia at https://vimeo.com/49458473This article contains multimedia at vimeo.com/49455976.

Treatment of Uremic Pruritus: A Systematic Review

BACKGROUND

Uremic pruritus is a common and burdensome symptom afflicting patients with advanced chronic kidney disease (CKD) and has been declared a priority for CKD research by patients. The optimal treatments for uremic pruritus are not well defined.

STUDY DESIGN

Systematic review.

SETTING & POPULATION

Adult patients with advanced CKD (stage ≥ 3) or receiving any form of dialysis.

SELECTION CRITERIA FOR STUDIES

PubMed, CINAHL, Embase, International Pharmaceutical Abstracts, Scopus, Cochrane Library, and ClinicalTrials.gov from their inception to March 6, 2017, were systematically searched for randomized controlled trials (RCTs) of uremic pruritus treatments in patients with advanced CKD (stage ≥ 3) or receiving any form of dialysis. 2 reviewers extracted data independently. Risk of bias was assessed using the Cochrane Collaboration risk-of-bias tool.

INTERVENTION

Any intervention for the treatment of uremic pruritus was included.

OUTCOMES

A quantitative change in pruritus intensity on a visual analogue, verbal rating, or numerical rating scale.

RESULTS

44 RCTs examining 39 different treatments were included in the review. These treatments included gabapentin, pregabalin, mast cell stabilizers, phototherapy, hemodialysis modifications, and multiple other systemic and topical treatments. The largest body of evidence was found for the effectiveness of gabapentin. Due to the limited number of trials for the other treatments included, we are unable to comment on their efficacy. Risk of bias in most studies was high.

LIMITATIONS

Heterogeneity in design, treatments, and outcome measures rendered comparisons difficult and precluded meta-analysis.

CONCLUSIONS

Despite the acknowledged importance of uremic pruritus to patients, with the exception of gabapentin, the current evidence for treatments is weak. Large, simple, rigorous, multiarm RCTs of promising therapies are urgently needed.

Inflammatory and Noninflammatory Itch: Implications in Pathophysiology-Directed Treatments

Itch is the main chief complaint in patients visiting dermatologic clinics and has the ability to deeply impair life quality. Itch results from activation of cutaneous nerve endings by noxious stimuli such as inflammatory mediators, neurotransmitters and neuropeptides, causing itch signal transduction from peripheral skin, through the spinal cord and thalamus, to the brain cortex. Primarily noninflammatory diseases, such as uremic pruritus, cause itch through certain pruritogens in the skin. In inflammatory skin diseases, atopic dermatitis (AD) is the prototypic disease causing intensive itch by aberrant skin inflammation and epidermal barrier disruption. Recent understanding of disease susceptibility, severity markers, and mechanisms have helped to develop targeted therapy for itch in AD, including monoclonal antibodies against IL-4, IL-13, thymic stromal lymphopoietin (TSLP), IgE and IL-31. Promising effects have been observed in some of them. In this review, we summarized targeted therapies for inflammatory itch in AD and for managing abnormal itch transductions in other common itching skin diseases.

Adjunctive Management of Itch in Atopic Dermatitis

Itch, or pruritus, is a hallmark feature of atopic dermatitis (AD). The impact of AD-related pruritus can range from mildly distressing or distracting to completely disabling. Traditionally, management of itch in AD patients has focused on restoring the altered skin barrier with topical emollients and/or reducing inflammation. A growing emphasis has been placed on directly targeting the neural transmission pathways that mediate itch signaling. Off-label use of neuromodulatory agents has helped reduce this aggravating symptom in atopic patients. This article reviews the current literature on the use of neuromodulatory agents and nonpharmacologic alternative therapies used to treat AD-related pruritus.

Development of a multidimensional assessment tool for uraemic pruritus: Uraemic Pruritus in Dialysis Patients (UP-Dial)

BACKGROUND

Dialysis patients with uraemic pruritus (UP) have significantly impaired quality of life. To assess the therapeutic effect of UP treatments, a well-validated comprehensive and multidimensional instrument needed to be established.

OBJECTIVES

To develop and validate a multidimensional scale assessing UP in patients on dialysis: the Uraemic Pruritus in Dialysis Patients (UP-Dial).

METHODS

The development and validation of the UP-Dial instrument were conducted in four phases: (i) item generation, (ii) development of a pilot questionnaire, (iii) refinement of the questionnaire with patient recruitment and (iv) psychometric validation. Participants completed the UP-Dial, the visual analogue scale (VAS) of UP, the Dermatology Life Quality Index (DLQI), the Kidney Disease Quality of Life-36 (KDQOL-36), the Pittsburgh Sleep Quality Index (PSQI) and the Beck Depression Inventory (BDI) between 15 May 2012 and 30 November 2015.

RESULTS

The 27-item pilot UP-Dial was generated, with 168 participants completing the pilot scale. After factor analysis was performed, the final 14-item UP-Dial encompassed three domains: signs and symptoms, psychosocial, and sleep. Face and content validity were satisfied through the item generation process and expert review. Psychometric analysis demonstrated that the UP-Dial had good convergent and discriminant validity. The UP-Dial was significantly correlated [Spearman rank coefficient, 95% confidence interval (CI)] with the VAS-UP (0·76, 0·69-0·83), DLQI (0·78, 0·71-0·85), KDQOL-36 (-0·86, -0·91 to -0·81), PSQI (0·85, 0·80-0·89) and BDI (0·70, 0·61-0·79). The UP-Dial revealed excellent internal consistency (Cronbach's α 0·90, 95% CI 0·87-0·92) and reproducibility (intraclass correlation 0·95, 95% CI 0·90-0·98).

CONCLUSIONS

The UP-Dial is valid and reliable for assessing UP among patients on dialysis. Future research should focus on the cross-cultural adaptation and translation of the scale to other languages.

[Pruritus in systemic diseases : Common and rare etiologies]

Chronic pruritus is a symptom of various internal disorders. In contrast to dermatological diseases, pruritus does not present with primary skin alterations in these patients. However, intense scratching may cause secondary skin changes such as abrasion, excoriation, prurigo nodularis, or in rare cases even scaring. The most common internal medicine causes for chronic pruritus are chronic kidney disease, hepatobiliary and hematological disorders as well as adverse drug reactions. Pruritus is less commonly seen in patients with endocrine or metabolic diseases, malabsorption syndromes, infectious diseases and solid tumors. The pathogenesis of pruritus in these disorders remains largely elusive, albeit preliminary insights have been gained for uremic and cholestatic pruritus. Antipruritic treatment is therefore symptomatic in most cases and may represent a clinical challenge. The calcium channel blockers gabapentin and pregabalin have the best proven efficacy in chronic kidney disease-associated pruritus. In Japan nalfurafine, a κ-opioid receptor agonist, has been licensed for this indication. UVB light may also attenuate uremic symptoms. In patients suffering from hepatobiliary disorders the sequestrant cholestyramine and the enzyme inducer rifampicin are effective. Furthermore, μ‑opioid receptor antagonists and sertraline may be used to ameliorate cholestatic pruritus. So far, no randomized controlled trials have been performed for chronic itch in other internal medicine disorders. Antipruritic treatment is mainly based on effective therapy of the underlying disease.