Psychometric properties of the Itch Numeric Rating Scale in patients with moderate-to-severe plaque psoriasis.

BACKGROUND: Itching is a profoundly distressing symptom for many patients with psoriasis, but it has not been rigorously studied using validated tools for this condition. OBJECTIVES: This study investigated the psychometric properties of the Itch Numeric Rating Scale (Itch NRS), a single-item patient-reported outcome (PRO) measuring the worst itching severity due to psoriasis in the past 24 h. METHODS: Using disease-specific clinician-rated and PRO data from one phase II and three phase III randomized clinical studies of subjects with moderate-to-severe plaque psoriasis, the Itch NRS was evaluated for test-retest reliability, construct validity and responsiveness. A responder definition was explored using anchor- and distribution-based methods. RESULTS: Test-retest reliability analyses supported the reproducibility of the measure (intraclass correlation coefficient range 0·71-0·74). To support the construct validity of the Itch NRS, large cross-sectional correlations with the Dermatology Life Quality Index (DLQI) Symptoms and Feelings domain (r ≥ 0·60 at baseline and r ≥ 0·80 at week 12) supported a priori hypotheses, while large correlations (r ≥ 0·71) between changes in Itch NRS scores and changes in DLQI Symptoms and Feelings domain scores from baseline to week 12 established responsiveness. A 4-point change was optimal for demonstrating a level of clinically meaningful improvement in itch severity after 12 weeks of treatment, which corresponds with marked clinical improvements in plaque psoriasis. CONCLUSIONS: The Itch NRS demonstrated sufficient reliability, validity and responsiveness, and appropriate interpretation standards for evaluating change over time in itch severity among patients with moderate-to-severe plaque psoriasis when validated using clinical trial data for this condition.

Limitations of current treatments for systemic lupus erythematosus: a patient and physician survey.

An independent cross-sectional survey assessed systemic lupus erythematosus (SLE) disease and treatment burden. Variables included medication classes prescribed, disease activity, flare occurrences, treatment satisfaction, and validated measures of health-related quality of life (HRQoL), fatigue and work productivity. Of 886 eligible patients (mean age 41.3 years, 89% female), 515 completed the survey. One-third reported moderate-to-severe disease activity, and 31% had flared in the last 12 months. Higher severity of disease activity (moderate-to-severe) was associated with ≥ 2 medication classes prescribed and treatment regimens that included corticosteroids (CS) (both p<0.0001). Patients receiving CS reported lower EQ-5D scores (p=0.0019) and higher fatigue levels (p<0.001), and both patients (p=0.0019) and physicians (p=0.0001) were less likely to report satisfaction with treatment regimens including CS. Among responders eligible for work (n=456), severity of disease activity (moderate-to-severe vs. mild) was associated with unemployment (52.9% vs. 40.8%; p=0.0189), greater impairment in work productivity (36% vs. 21%; p=0.0003) and participation in daily activities (41% vs. 21%; p<0.0001). This survey confirms that SLE and current treatment options substantially impair patients' health status and work productivity. Physician- and patient-reported satisfaction with current treatment regimens, despite poorly controlled disease activity, indicate they are resigned to the limitations of available SLE treatment regimens.