The Sleep Disturbance Numerical Rating Scale: Content Validity, Psychometric Validation, and Meaningful Within-Patient Change in Prurigo Nodularis

Content Validity and Psychometric Validation of an Adapted Version of the Subject Sleep Diary in Prurigo Nodularis

INTRODUCTION

Patients with prurigo nodularis (PN) often experience sleep disturbance. A psychometric evaluation was conducted to assess the suitability of a PN-adapted multi-item subject sleep diary (SSD) for measuring PN-related sleep disturbance.

METHODS

Content validity of the SSD was evaluated through qualitative interviews with adults with PN (N = 21). Psychometric properties of SSD parameters (sleep onset latency [SOL], wakefulness after sleep onset [WASO], total awake time [TWT], total sleep time [TST], sleep efficiency [SE], PN-related WASO [WASO-PN], number of WASO-PN, and sleep quality/refresh [SQR]) were evaluated using data from adults with moderate-to-severe PN in the phase 3 OLYMPIA trials (NCT04501666 [N = 286], NCT04501679 [N = 274]). The relationship between SSD parameters and the single-item Sleep Disturbance Numerical Rating Scale (SD-NRS) was examined using equipercentile linking.

RESULTS

Most interview participants who responded to cognitive debriefing questions understood the SSD as intended (≥ 80% for each item), confirming content validity. All SSD parameters showed good test-retest reliability. At week 16, all SSD parameters but TST showed moderate-to-strong correlations, in the expected direction, with the SD-NRS, Peak Pruritus NRS (PP-NRS), Average Pruritus (AP) NRS, Dermatology Life Quality Index (DLQI), PN-related pain frequency and intensity, Prurigo Activity and Severity Score (PAS), and/or Investigator's Global Assessment (IGA). Known-groups validity was adequate for all SSD parameters based on the Patient Global Impression of Severity-Sleep Disturbance (PGIS-SD), Patient Global Assessment of Disease (PGAD), PP-NRS, DLQI, and/or IGA. All parameters but TST were responsive to improvements on the PGIS-SD, Patient Global Impression of Change-Sleep Disturbance, PGAD, PP-NRS, AP NRS, PN-related pain intensity, DLQI, and/or IGA. Cross-sectional values or value changes of the SD-NRS were moderately to strongly correlated with SSD parameters, and equipercentile linking analyses revealed non-linear relationships between the measures.

CONCLUSIONS

The findings suggest that the SSD is a fit-for-purpose measure that can be used to assess sleep disturbance in moderate-to-severe PN.

CLINICAL TRIAL REGISTRATION

NCT04501666, NCT04501679.

Association of sleep disturbance and itch intensity with quality-of-life impairment and disease severity in prurigo nodularis

In this study, we explored the relationship between itch intensity, sleep disturbance and quality-of-life (QoL) impairment in patients with prurigo nodularis (PN). Using validated assessment tools, we found significant correlations between self-reported itch severity, objective disease measures, and their impact on sleep and QoL. These findings highlight the profound burden of PN on patients’ daily lives and the importance of addressing both itch and sleep disturbances in managing this condition.

Which Interventions Are Effective in Treating Sleep Disturbances After THA or TKA? A Systematic Review

BACKGROUND

Poor sleep quality is a common complaint after total joint arthroplasty (TJA), and it is associated with reports of higher pain and worse functional outcomes. Several interventions have been investigated with the intent to reduce the incidence of postoperative sleep disturbance with varying effectiveness. An aggregate of the best available evidence, along with an evaluation of the quality of those studies, is needed to provide valuable perspective to physicians and to direct future research.

QUESTIONS/PURPOSES

In this systematic review, we asked: (1) What is the reported efficacy of the most commonly studied medications and nonpharmacologic approaches, and (2) what are their side effects and reported complications?

METHODS

This systematic review was conducted in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A search using a combination of controlled vocabulary and keywords was performed utilizing Medline (Ovid), Embase (Ovid), Cochrane Central, and Web of Science databases from database inception to 2023, with the last search occurring October 24, 2023, to identify studies that evaluated a sleep intervention on the effect of patient-reported sleep quality after THA or TKA. Inclusion criteria were clinical trials, comparative studies, and observational studies on adult patients who underwent primary TKA or THA for osteoarthritis and who completed validated sleep questionnaires to assess sleep quality postoperatively. We excluded studies on patients younger than 18 years, patients with sleep apnea, TKA or THA because of trauma or conditions other than osteoarthritis, revision TJA, studies in languages other than English, and studies from nonindexed journals or preprint servers. Two investigators independently screened 1535 studies for inclusion and exclusion criteria and extracted data from the included studies. Ultimately, 14 studies were included in this systematic review, including 12 randomized controlled trials and 2 prospective comparative studies. A total of 2469 participants were included, with a mean ± SD age of 65 ± 7 years and 38% men in control groups and 65 ± 7 years and 39% men in intervention groups. Sleep quality questionnaires utilized included the Pittsburgh Sleep Quality Index, Self-Rating Scale of Sleep, 100-mm VAS - Sleep, Sleep Disturbance Numeric Rating Scale, Likert scales, and one institutionally designed questionnaire. Quality analysis was performed utilizing the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Randomized Controlled Trials, where higher scores of 13 indicated a more reliable study, and the Newcastle-Ottawa Quality Assessment Scale for Cohort Studies, where higher scores of 9 indicated a more reliable study and scores < 5 represented a high risk of bias. Two of the randomized controlled trials scored a 12 of 13, and the remaining 10 met every criteria of the JBI checklist. Both comparative studies scored 5 of 9 possible points of the Newcastle-Ottawa Scale.

RESULTS

Melatonin and selective cyclooxygenase-2 inhibitor rofecoxib were found to provide a clinically important benefit to sleep quality within the first postoperative week after TJA. However, rofecoxib was withdrawn from the market globally in 2004 over concerns about increased risk of cardiovascular events. Another cyclooxygenase-2 inhibitor, celecoxib, remains available. No other intervention demonstrated a clinical benefit. Side effects of melatonin include dizziness, headache, paresthesia, and nausea, and it is contraindicated in patients with liver failure, autoimmune conditions, or who are receiving warfarin. Long-term adverse effects of rofecoxib include hypertension, edema, and congestive heart failure, and it is contraindicated in patients with renal insufficiency or who are receiving warfarin. Melatonin is considered safe in older patients, but more caution should be taken with rofecoxib.

CONCLUSION

Owing to limited evidence in support of most of the interventions we studied, none of these interventions can be recommended for routine use after TJA. Melatonin and rofecoxib may provide a benefit to sleep quality in some patients, but physicians need to understand the adverse effects and contraindications before recommending these interventions. Additionally, rofecoxib is no longer commercially available. Future investigation is warranted to evaluate the effectiveness of interventions with minimal side effect profiles for providers to be able to make an informed decision about interventions for sleep improvement after TJA.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Impact of Difelikefalin on the Health-Related Quality of Life of Haemodialysis Patients with Moderate-To-Severe Chronic Kidney Disease-Associated Pruritus: A Single-Arm Intervention Trial

OBJECTIVE

Chronic kidney disease-associated pruritus (CKD-aP) can have a substantial negative impact on health-related quality of life (HRQoL), including an increased risk of depression, anxiety and sleep disturbance. This trial aimed to assess the impact of intravenous difelikefalin on HRQoL in haemodialysis patients with moderate-to-severe CKD-aP.

METHODS

Post hoc analysis of an open-label, multicentre, single-arm intervention trial assessed pruritus severity and HRQoL at baseline and at 12 weeks of difelikefalin treatment using Worst Itching Intensity Numerical Rating Scale (WI-NRS), Sleep Quality Numeric Rating Scale (SQ-NRS), 5-D itch scale, Skindex-10 scale, EQ-5D-5L with Pruritus Bolt-On (EQ-PSO).

RESULTS

A total of 222 patients received ≥ 1 dose of difelikefalin, and 197 patients completed 12 weeks of difelikefalin treatment. Clinically meaningful changes from baseline to 12 weeks were observed in all disease-specific measures: 73.7% of patients achieved a ≥ 3-point reduction in the weekly mean of 24 h WI-NRS scores and 66% of patients experienced ≥ 3-point improvements in SQ-NRS scores. Improvements were also observed in all Skindex-10 scale and 5-D itch scale domain scores. The percentage of patients reporting no problems in all EQ-PSO domains increased from 1.4 to 24.7% (p < 0.001), respectively. Patients' generic HRQoL EQ-5D-5L mean utility and EQ-5D visual analogue scale scores increased from baseline to 12 weeks: mean changes 0.04 (p = 0.001) and 2.8 (p = 0.046), respectively.

CONCLUSIONS

Patients undergoing haemodialysis with moderate-to-severe CKD-aP receiving difelikefalin reported experiencing clinically meaningful improvements in both their pruritus symptoms and itch-related QoL.

CLINICALTRIALS

gov registration number, NCT03998163; first submitted, 7 May 2019.