Multidimensional pruritus assessment in hemodialysis patients

Chronic kidney disease-associated pruritus: what is known and its application in children

Chronic kidney disease-associated pruritus (CKD-aP) or uremic pruritus (UP) is a frequent symptom in patients with kidney failure receiving kidney replacement therapy. Severe chronic kidney disease-associated pruritus correlates with poor outcome in patients on dialysis. It is multifactorial in etiology and has a significant impact on quality of life. There is, however, limited data for children. This review summarizes current epidemiology, clinical characteristics, pruritus scoring systems, and available therapeutic options for pruritus in patients with chronic kidney disease and those receiving dialysis. Optimal care requires proper awareness of the severity of symptoms, the impact on quality of life, and the possible long-term outcomes. Optimizing dialysis prescription and correcting electrolyte abnormalities are important treatment targets. A wide range of therapeutic options is also available although none are well-studied in children. An earlier recognition of this debilitating symptom in children and treatment is imperative. A higher resolution version of the Graphical abstract is available as Supplementary information.

The Burden of Pruritus Associated With CKD: A Mixed Methods Analysis Among Patients Undergoing Dialysis

Rationale & Objective

Despite its prevalence and distress to patients, chronic kidney disease-associated pruritus (CKD-aP) is poorly characterized, which may contribute to the condition's underdiagnosis and inadequate management. This study aimed to understand the symptom experience of patients with CKD-aP and the extent to which pruritus impacts their lives.

Study Design

Mixed methods study including one-on-one qualitative interviews and completion of the Skindex-10 Questionnaire (measuring itch-related quality of life).

Setting & Participants

A total of 23 patients undergoing hemodialysis and reporting pruritus at 4 dialysis centers in the United States.

Analytical Approach

Interviews followed a semistructured guide that included targeted and follow-up questions to elicit discussion of patients' symptoms of pruritus, including frequency and variability, impact on activities of daily living, and emotional and social functioning. Interviews were digitally audio-recorded. A coding dictionary was developed from transcripts to analyze themes and concepts.

Results

Participants described their itch with various terms, including "numbness," "pain," and "tingling" on their skin. Itch affected multiple areas but especially the back, usually occurred daily, and was often worse at night. For some, itching was a constant experience. Patients relieved their itch through scratching and various off-label treatments; some reported skin damage from excessive scratching and most indicated treatments provided limited relief. Pruritus considerably disrupted physical function, including sleep, daily activities, social functioning and relationships, and emotional and psychological wellbeing. All participants reported being bothered by their itching during the past week on the Skindex-10 Questionnaire.

Limitations

All participants were from the United States, so the findings may not be generalizable to other countries.

Conclusions

Although symptom experience varies considerably, CKD-aP causes severe distress for many patients undergoing hemodialysis and can profoundly impair their quality of life. The results of this study show the impact of itch from patients' perspectives and highlight the need for greater awareness and better management of this condition.

Plain-Language Summary

Patients with chronic kidney disease often experience itching, or pruritus, but its importance to patients is regularly overlooked. This study used one-on-one interviews to investigate patients' experiences of chronic kidney disease-associated pruritus and how it impacts their lives. We found that participants experienced itch on various body areas and used different words to describe their itch (eg, "numbness" and "pain"). Some reported skin damage from excessive scratching, and many used off-label treatments and other interventions (eg, rubbing alcohol and multiple showers daily), which provided limited relief. For many, itching was experienced daily and severely disrupted sleep, daily activities, interactions with others, and mental wellbeing. These findings reveal chronic kidney disease-associated pruritus severely impacts patients and highlights the need for improved management of this condition.

The effectiveness of sertraline in alleviating uremic pruritus in hemodialysis patients: a randomized clinical trial

INTRODUCTION

Uremic pruritus (UP) is a common and distressing symptom in end stage renal disease (ESRD) patients. Many approaches have been tested to improve UP without a clear success. We aimed to assess the effect of sertraline on UP in hemodialysis (HD) patients.

METHODS

This research is a double-blinded, placebo-controlled, multicentric randomized clinical trial which included sixty patients maintained on regular HD. Patients were allocated to receive sertraline 50 mg twice daily or placebo for 8 weeks. The Visual analogue scale (VAS) and the 5-D itch scale were used to assess pruritus before and after the course of treatment.

RESULTS

At study end in sertraline group, there was a significant decrease from baseline findings in the VAS score (p < 0.001), and the 5-D itch scale (p < 0.001). On the other hand, in placebo group the VAS score showed a slight non-significant decrease (p = 0.469), and the 5-D scale (p = 0.584) increased from baseline measurements. The percentage of patients with severe and very severe pruritus decreased significantly in the sertraline group in both scores [(VAS score: p = 0.004), (5-D itch score: p = 0.002)] with no significant change in the placebo group [(VAS score: p = 0.739), (5-D itch scale: p = 0.763)]. There was a significant positive relation between the VAS and 5-D itch scores and serum urea with p value of 0.002 and 0.001 respectively, and serum ferritin with p value of < 0.001 with both.

CONCLUSIONS

Patients treated with sertraline had a significant improvement in pruritus as compared with those who received placebo suggesting a potential role for sertraline to treat uremic pruritus in HD patients. Larger randomized clinical trials are needed to confirm these findings.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05341843. First registration date: 22/04/2022.

Mental health and its influencing factors of maintenance hemodialysis patients: a semi-structured interview study

BACKGROUND

Maintenance hemodialysis (MHD) is a commonly used renal replacement therapy for end-stage renal disease patients. MHD patients have undergone multiple physiological stressors, which may cause physical problems and affect their mental health; however, few qualitative studies have been done on the mental health of MHD patients. Such qualitative research becomes the basis for further quantitative research and is critical to validating its results. Therefore, the current qualitative study used a semi-structured interview format, and aimed to explore the mental health and its influencing factors of MHD patients who are not receiving intervention treatment to determine how best to ameliorate their mental health.

METHODS

Based on the application of Grounded Theory, semi-structured face-to-face interviews were conducted with 35 MHD patients, following consolidated criteria for reporting qualitative studies (COREQ) guidelines. Two indicators (emotional state and well-being) were used to assess MHD patients' mental health. All interviews were recorded, after which two researchers independently performed data analyses using NVivo.

RESULTS

Acceptance of disease, complications, stress and coping styles, and social support were found to be the influencing factors of MHD patients' mental health. High acceptance of disease, healthy coping styles, and high social support were positively correlated with mental health. In contrast, low acceptance of disease, multiple complications, increased stress, and unhealthy coping styles were negatively correlated with mental health.

CONCLUSION

One's acceptance of the disease played a more significant role than other factors in affecting MHD patients' mental health.

Clinical Efficacy and Safety of Sodium Thiosulfate in the Treatment of Uremic Pruritus: A Meta-Analysis of Randomized Controlled Trials

Uremic pruritus is a distressful complication of chronic kidney disease and results in impaired quality of life and higher mortality rates. Intravenous sodium thiosulfate has been reported to alleviate pruritus in hemodialysis patients. We performed a systematic review and meta-analysis to estimate the efficacy of intravenous sodium thiosulfate in patients with uremic pruritus. A systematic search of electronic databases up to June 2021 was conducted for randomized controlled trials that evaluated the clinical effects of sodium thiosulfate in the management of patients with uremic pruritus. Two reviewers selected eligible articles and evaluated the risk of bias; the results of pruritus assessment and uremic pruritus-related laboratory parameters in selected studies were analyzed. There are four trials published between 2018 and 2021, which include 222 participants. The sodium thiosulfate group displayed significant decrease in the pruritus score (standardized mean difference = -3.52, 95% confidence interval = -5.63 to -1.41, p = 0.001), without a significant increase in the adverse effects (risk ratio = 2.44, 95% confidence interval = 0.37 to 15.99, p = 0.35) compared to the control group. Administration of sodium thiosulfate is found to be a safe and efficacious complementary therapy in improving uremic pruritus in patients with chronic kidney disease.

Effects of Uremic Clearance Granules in Uremic Pruritus: A Meta-Analysis

Uremic pruritus is common among patients with advanced or end-stage renal disease, with an incidence of >40% among patients on dialysis. Uremic clearance granules (UCGs) are effective in managing uremic pruritus and delay the progression of chronic kidney disease. We conducted a systematic review and a meta-analysis to evaluate the efficacy of UCG in patients with uremic pruritus. Several electronic databases were searched systematically from their inceptions until 19 July 2021. Randomized control trials evaluating the efficacy of UCG in patients with uremic pruritus were selected. Eleven trials including 894 participants were published between 2011 and 2021. Patients administered UCGs had a significantly decreased visual analog scale score (mean difference [MD], -2.02; 95% confidence interval [CI], -2.17 to -1.88), serum levels of hsCRP (MD, -2.07 mg/dL; 95% CI, -2.89 to -1.25; p < 0.00001), TNF-α (MD, -15.23 mg/L; 95% CI, -20.00 to -10.47; p < 0.00001]), β2-MG (MD, -10.18 mg/L; 95% CI, -15.43 to -4.93; p < 0.00001), and IL-6 (MD, -6.13 mg/L; 95% CI, -7.42 to -4.84; p < 0.00001). In addition, UCGs significantly reduced serum levels of creatinine, BUN, PTH, iPTH, phosphorus, and the overall effectiveness rate. UCGs could be an attractive complementary therapy for patients with uremic pruritus.

Association between Financial Hardship and Symptom Burden in Patients Receiving Maintenance Dialysis: A Systematic Review

BACKGROUND

Many patients on maintenance dialysis experience financial hardship. Existing studies are mainly cost analyses that quantify financial hardship in monetary terms, but an evaluation of its impact is also warranted. This review aims to explore the definition of financial hardship and its relationship with symptom burden among patients on dialysis.

METHODS

A literature search was conducted in November 2020, using six electronic databases. Studies published in English that examined the associations between financial hardship and symptom burden were selected. Two reviewers independently extracted data and appraised the studies by using the JBI Critical Appraisal Checklists.

RESULTS

Fifty cross-sectional and seven longitudinal studies were identified. Studies used income level, employment status, healthcare funding, and financial status to evaluate financial hardship. While relationships between decreased income, unemployment, and overall symptom burden were identified, evidence suggested that several symptoms, including depression, fatigue, pain, and sexual dysfunction, were more likely to be associated with changes in financial status.

CONCLUSION

Our findings suggest that poor financial status may have a negative effect on physical and psychological well-being. However, a clear definition of financial hardship is warranted. Improving this assessment among patients on dialysis may prompt early interventions and minimize the negative impact of financial hardship.

Chronic Kidney Disease-Associated Pruritus

Pruritus is a distressing condition associated with end-stage renal disease (ESRD), advanced chronic kidney disease (CKD), as well as maintenance dialysis and adversely affects the quality of life (QOL) of these patients. It has been reported to range from 20% to as high as 90%. The mechanism of CKD-associated pruritus (CKD-aP) has not been clearly identified, and many theories have been proposed to explain it. Many risk factors have been found to be associated with CKD-aP. The pruritus in CKD presents with diverse clinical features, and there are no set features to diagnose it.The patients with CKD-aP are mainly treated by nephrologists, primary care doctors, and dermatologists. Many treatments have been tried but nothing has been effective. The search of literature included peer-reviewed articles, including clinical trials and scientific reviews. Literature was identified through March 2021, and references of respective articles and only articles published in the English language were included.

A basophil-neuronal axis promotes itch

Itch is an evolutionarily conserved sensation that facilitates expulsion of pathogens and noxious stimuli from the skin. However, in organ failure, cancer, and chronic inflammatory disorders such as atopic dermatitis (AD), itch becomes chronic, intractable, and debilitating. In addition to chronic itch, patients often experience intense acute itch exacerbations. Recent discoveries have unearthed the neuroimmune circuitry of itch, leading to the development of anti-itch treatments. However, mechanisms underlying acute itch exacerbations remain overlooked. Herein, we identify that a large proportion of patients with AD harbor allergen-specific immunoglobulin E (IgE) and exhibit a propensity for acute itch flares. In mice, while allergen-provoked acute itch is mediated by the mast cell-histamine axis in steady state, AD-associated inflammation renders this pathway dispensable. Instead, a previously unrecognized basophil-leukotriene (LT) axis emerges as critical for acute itch flares. By probing fundamental itch mechanisms, our study highlights a basophil-neuronal circuit that may underlie a variety of neuroimmune processes.

Reliability and validity of the Persian version of 5-D itching scale among patients with chronic kidney disease

BACKGROUND

Hemodialysis is considered a major therapeutic method for patients with chronic kidney disease. Pruritus is a common complaint of hemodialysis patients. The 5-D pruritus scale is amongst the most common tools to evaluate several dimensions of itch. Psychometric properties of the 5-D scale have not been evaluated in Persian speaking population with hemodialysis; hence, the objective of this study was to assess reliability and validity of the Persian version of the scale.

METHODS

Ninety hemodialysis patients (men: 50, women: 40, mean age: 54.4 years) participated in this cross-sectional study. The final Persian version of 5-D scale was given to the participants. Tests Compared: One-third of the participants completed the scale twice within 3-7 days apart to evaluate test- retest reliability. Other psychometric properties including internal consistency, absolute reliability, convergent, discriminative and construct validity, floor/ceiling effects were also evaluated.

RESULTS

The Persian 5-D scale has strong test-retest reliability (ICC= 0.98) and internal consistency (Cronbach's alpha= 0.99). Standard error of measurement and minimal detectable change were 0.33 and 0.91, respectively. Regarding convergent validity, the scale had moderate correlation with numeric rating scale (r =0.67) and quality of life questionnaire related to itch (r = 0.59). Exploratory factor analysis revealed two factors within the scale. No floor or ceiling effect was found for the scale.

CONCLUSION

The Persian version of 5-D the itching scale is a brief instrument with acceptable reliability and validity. Therefore, the scale could be used by experts, nurses, and other health service providers to evaluate pruritus among Persian speaking hemodialysis patients.

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.

Factors associated with the severity of pruritus in patients with terminal chronic kidney disease undergoing hemodialysis in Lima, Peru

The objective of the study is to analyze the factors associated with the severity of pruritus in patients with terminal chronic kidney disease undergoing hemodialysis. The methodology used is based on a cross-sectional study in patients receiving hemodialysis at the Centro Nacional de Salud Renal. Severe pruritus was defined as a score on the visual analogue scale greater than or equal to 7, and the strength of association with the possible risk factors was assessed by calculating prevalence ratios. Regarding the results, 264 patients were included, 59.9% were male, with a mean time on hemodialysis of 10.26 ± 7.14 years. 75% experienced pruritus, of this group, 1 in 3 presented severe pruritus. Hyperphosphatemia and the use of antihistamines were associated with a higher prevalence of severe pruritus (RP 1.71, 95% CI 1.09-267 and RP 2.39, 95% CI 1.51-3.75, respectively). The positive serology for Hepatitis C Virus was described as a protective factor for presenting severe pruritus (RP 0.55, 95% CI 0.33-0.89). In conclusion, severe uremic pruritus is a frequent problem in patients with chronic terminal kidney disease who have hyperphosphatemia and treatment with antihistamines independently of the time they have been on 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.