Comorbidities, healthcare resource utilization & treatment pattern among patients with prurigo nodularis, compared to a benchmark in Germany: A real-world evidence claims data study.

BACKGROUND: Prurigo nodularis (PN) is a rare chronic inflammatory skin disease with a high disease burden, but data on clinical and economic burden are still scarce. OBJECTIVE: To describe the real-world epidemiologic, clinical and therapeutic characteristics and related economic burden of patients with PN compared to a benchmark population in Germany. METHODS: This retrospective study was based on an excerpt of German Statutory Health Insurance data of patients with an initial PN diagnosis between 2012 and 2016. PN cohort contained no record of PN in eight quarters before the index quarter and was followed up for eight quarters (unless deceased). Benchmark cohort without PN was calculated using direct standardization and 1:1 matching to PN cohort. RESULTS: Out of 4,536,002 insured patients, 2309 incident patients with PN were identified and matched to the benchmark cohort out of 3,018,382 patients without PN. Patients were mostly between 45 and 80 years when diagnosed with PN. Higher comorbidity rates were reported for PN than benchmark, with a rising disease burden at follow-up. Most patients with PN (91.3%) were diagnosed outpatient and had >50% more outpatient visits than the benchmark cohort. Hospitalization rates were higher in PN (53.9%) versus benchmark (35.1%), yielding twice longer mean hospital stays for PN (12 days) compared to benchmark (6 days) (p < 0.001). The most common initial therapy for patients with PN was topical corticosteroids (47.6%); ≥10% of patients were treated with antidepressants, antihistamines or systemic corticosteroids. Therapy rates were higher for PN compared to benchmark (p < 0.001). Mean initial costs were twofold higher in PN versus benchmark for outpatient, inpatient and drugs. During follow-up, an increase of >70% in mean PN costs compared to benchmark was identified for outpatient, inpatient and concomitant treatments (p < 0.001). CONCLUSION: This study highlights the significantly higher clinical and economic burden incurred by PN compared to benchmark patients in Germany, reflecting the unmet medical need for PN.

Incident Comorbidity, Resource Use, and All-Cause Mortality Associated with Prurigo Nodularis: A United Kingdom Retrospective Database Analysis.

We described comorbidity, resource utilization, and mortality for patients with prurigo nodularis (PN) using data from the Clinical Practice Research Datalink. Patients with incident PN (2008-2018) were selected and matched to controls. Of 2,416 patients with PN, 2,409 (99.7%) were matched to controls. Prevalence of atopic dermatitis (relative risk [RR] = 2.571; 95% confidence interval [CI] = 2.356-2.806), depression (RR = 1.705; 95% CI = 1.566-1.856), anxiety (RR = 1.540; 95% CI = 1.407-1.686), coronary heart disease (RR = 1.575; 95% CI = 1.388-1.787), chronic kidney disease (RR = 1.529; 95% CI = 1.329-1.759), and type 2 diabetes mellitus (RR = 1.836; 95% CI = 1.597-2.111) was significantly higher for patients with PN. Subsequent risk of atopic dermatitis (hazard ratio = 6.58; 95% CI = 5.17- 8.37), depression (hazard ratio = 1.61; 95% CI = 1.30-1.99), and coronary heart disease (hazard ratio = 1.37; 95% CI = 1.09-1.74) were significantly increased. Resource utilization was increased in all settings: incidence rate ratio = 1.48 (95% CI = 1.47-1.49) for primary care, incident rate ratio = 1.80 (95% CI = 1.75-1.85) for inpatients, incident rate ratio = 2.15 (95% CI = 2.13-2.18) for outpatients, and incidence rate ratio = 1.32 (95% CI = 1.27-1.36) for accident and emergency. Respective cost ratios were 1.78 (95% CI = 1.67-1.90), 1.52 (95% CI = 1.20-1.94), 2.34 (95% CI = 2.13-2.58), and 1.55 (95% CI = 1.33-1.80). Total primary and secondary healthcare costs were £2,531 versus £1,333, a cost ratio of 1.62 (95% CI = 1.36-1.94). The adjusted hazard ratio for mortality was 1.37 (95% CI = 1.14-1.66). Patients with PN had significantly increased rates of comorbidity, healthcare resources utilization, and mortality compared with matched controls.

Risk of incident sleep disorders in patients with prurigo nodularis: A population-level analysis using The Health Improvement Network.

Background: Prurigo nodularis (PN) is a chronic inflammatory skin condition characterized by severely itchy and often painful bumps on the arms, legs, and trunk. It is unknown whether patients with PN have increased risk of developing sleep disorders. Objective: To evaluate the association of PN with sleep disorders. Methods: This retrospective, population-level, matched-cohort study was conducted using The Health Improvement Network. The study included 4193 patients with newly diagnosed PN and 4193 age, sex, and race/ethnicity-matched controls. A Cox regression model was used to assess the development of sleep disorders, including insomnia, sleep apnea, and restless legs syndrome, in patients with PN compared with control patients. Results: Compared with controls, PN was associated with insomnia (adjusted hazard ratio [aHR] = 1.77; 95% CI = 1.48-2.12) and overall sleep disorder (aHR = 1.72; 95% CI = 1.46-2.02), but not with sleep apnea (aHR = 1.51; 95% CI = 0.93-2.44) or restless legs syndrome (aHR = 1.54; 95% CI = 0.92-2.57). Limitations: As a retrospective cohort study, our analysis is subject to potential confounders not already included. Conclusions: PN was associated with subsequent development of insomnia. Thus, clinicians should consider insomnia among patients with PN and develop strategies for treatment and prevention.

Validation of the Peak Pruritus Numerical Rating Scale as a Patient-Reported Outcome Measure in Prurigo Nodularis.

INTRODUCTION: Validated patient report tools for quantifying patient experiences of itch in prurigo nodularis (PN) are limited. This study aimed to evaluate the validity of the 11-point peak pruritus numerical rating scale (PP NRS) as a single-item patient-reported outcome (PRO) measure for assessing itch severity in PN. METHODS: Content validity of the PP NRS was evaluated through qualitative interviews with adults with PN. The PP NRS was then psychometrically evaluated using data from a placebo-controlled trial of nemolizumab in adults with PN, during which patients completed the PP NRS daily. Meaningful within-patient change was estimated from the qualitative interviews and by anchor- and distribution-based analyses of trial data. RESULTS: The interview participants (N = 21) all understood the PP NRS and reported itch as their worst symptom overall. The PP NRS showed good test-retest reliability and demonstrated convergent validity and known-groups validity. PP NRS scores improved more in patients classified as "improved" on other clinical outcome measures than in those classified as "worsened/unchanged". Triangulation of the different estimates identified a 2- to 5-point decrease in PP NRS score as a meaningful within-patient change threshold. CONCLUSION: The PP NRS is a content-valid and reliable PRO measure for quantifying itch severity in adults with PN in clinical trials. TRIAL REGISTRATION NUMBER: NCT03181503.

Prurigo nodularis is a skin disease where the skin becomes inflamed and very itchy. Itching and scratching can ruin the lives of people with prurigo nodularis. For doctors to know how well treatments for prurigo nodularis are working, they need to be able measure how bad their patients' itching is. Here we tested whether a tool called the peak pruritus numeric rating scale (PP NRS) can be used to reliably measure itching in patients with prurigo nodularis. The PP NRS asks patients to rate their itch "at the worst moment during the previous 24 h" on a scale from 0 ("no itch") to 10 ("worst itch imaginable"). We interviewed 21 patients with prurigo nodularis. Overall, itch was their worst symptom. They were able to use the PP NRS with few or no problems. To further explore whether the PP NRS can be used by patients with prurigo nodularis, we also obtained data from a clinical study. In this clinical study, patients with prurigo nodularis received a drug that might one day be used to treat their disease. They completed the PP NRS daily during the time they received the drug. When we analyzed the data from the clinical study, we found that the PP NRS has the properties a tool like this needs to be useful. We also concluded that a decrease of 2­5 points on the PP NRS scale would be a meaningful improvement in itching for patients with prurigo nodularis.

Longitudinal Course of Sleep Disturbance and Relationship With Itch in Adult Atopic Dermatitis in Clinical Practice.

Background: Sleep disturbance (SD) is common in atopic dermatitis (AD). We examined the longitudinal course of SD and relationship with itch in AD patients. Methods: A prospective, dermatology practice-based study was performed (N = 1295) where patients were assessed at baseline and follow-up visits. Results: At baseline, 16.9% of the patients had severe SD based on Patient-Reported Outcomes Information System (PROMIS) SD T scores, 19.1% had difficulty falling asleep, 22.9% had difficulty staying asleep, and 34.2% had SD from AD. A total of 31.4% of the patients with difficulty staying asleep at baseline experienced persistent difficulties (for 3 follow-ups or more). Only 17.7% with baseline difficulty falling asleep had persistent disturbance. Despite significant fluctuation in sleep scores, SD generally improved over time. Of the patients facing baseline SD from AD, 31.5% experienced SD at the first visit, and only 12.3% experienced persistent SD at the second follow-up visit. Predictors of increased PROMIS sleep-related impairment T scores over time included baseline PROMIS sleep-related impairment T scores (0.74 [0.68-0.80]), having 3 to 6 nights of itch (2.22 [0.85-3.59]), and severe/very severe AD (4.40 [2.60-6.20]). Conclusions: A significant proportion of adult AD patients, particularly those with moderate-severe AD and frequent itch, had baseline SD. Although sleep scores generally improved over time, many patients experienced a fluctuating or persistent course.

An explanatory sequential mixed-methods design to establish thresholds of within-individual meaningful change on a sleep disturbance numerical rating scale score in atopic dermatitis.

PURPOSE: Establishing a meaningful within-individual change (MWIC) threshold is a key aspect for interpreting scores used as endpoints for evaluating treatment benefit. A new patient-reported outcome (PRO), a sleep disturbance numerical rating scale (SD NRS), was developed in adults and adolescents with moderate-to-severe atopic dermatitis (AD). This research aims to establish a MWIC threshold of the SD NRS score in the context of a drug development program. METHODS: An explanatory sequential mixed-methods design was used to address the research objective. This mixed-methods design used phase IIb data and a stand-alone qualitative study. Quantitative anchor-based and distribution-based approaches supported by qualitative-based approaches were conducted, and results were triangulated to determine preliminary MWIC thresholds of the SD NRS score. RESULTS: Triangulation of results from both quantitative and qualitative approaches suggested that a 2- to 6-point decrease in the SD NRS score change constitutes a preliminary range of MWIC threshold estimates. CONCLUSION: This research determined MWIC threshold estimates for the SD NRS score in both adolescents and adults with moderate-to-severe AD using an explanatory sequential mixed-methods design. This mixed-methods design provides interesting insights for establishing MWIC thresholds of a PRO score in the context of a drug development program.

Association of Adult Atopic Dermatitis Severity With Decreased Physical Activity: A Cross-sectional Study.

Background: Atopic dermatitis (AD) is associated with chronic pruritus, skin pain, sleep deprivation, depression, and anxiety, which may lead to decreased physical activity (PA). Objective: The aim of the study is to elucidate the impact of disease and itch severity on PA in adult AD. Methods: This is a prospective dermatology practice-based study of 955 AD patients (ages 18-97 years). Results: In multivariable logistic regression models controlling for age, sex, race/ethnicity, and asthma history, patient-reported global AD severity (PtGA), Patient-Oriented Eczema Measure, Eczema Area and Severity Index (EASI), and Investigator's Global Assessment (IGA) were associated with itch impairing light PA, moderate PA, and vigorous PA, as well as higher Patient-Reported Outcomes Measurement Information System Itch Questionnaire PA T-scores. Higher objective Scoring AD (O-SCORAD) was associated with itch impairing moderate PA. In bivariable analyses, performing greater than or equal to 30 minutes of light PA greater than or equal to 1 day a week was decreased with higher PtGA, Patient-Oriented Eczema Measure, and EASI; greater than or equal to 30 minutes of moderate PA greater than or equal to 1 day a week was decreased with PtGA, EASI, O-SCORAD, and IGA; and greater than equal to 30 minutes of vigorous PA was decreased with patient-reported AD severity, EASI, O-SCORAD, and IGA. In multivariable logistic regression models, the impact of itch on PA was inversely associated with light PA, moderate PA, and vigorous PA. Conclusion: Adult AD patients with more severe disease have decreased levels of PA secondary to itch.

Longitudinal course and predictors of depressive symptoms in atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) is associated with eczematous lesions, pruritus, pain, and sleep disturbance, which may negatively impact mental health over time. OBJECTIVE: To determine the predictors and longitudinal course of depressive symptoms in adults with AD. METHODS: A prospective, dermatology practice-based study was performed (N = 695). AD signs, symptoms, and severity and patient health questionnaire-9 (PHQ-9) were assessed. RESULTS: At baseline, of the 695 participants, 454 (65.32%) had minimal, 139 (20.00%) had mild, 57 (8.20%) had moderate, 27 (3.88%) had moderately severe, and 8 (2.59%) had severe depression. Most had fluctuating levels of depressive symptoms. Feeling bad, thoughts of self-harm, difficulty concentrating, and slow movement were most persistent. Predictors of persistent depression included older age, non-White race, male sex, public or no insurance, more severe itch, skin pain, facial erythema, nipple eczema, sleep disturbance, and presence of pityriasis alba. LIMITATIONS: Single center study. CONCLUSION: Depressive symptoms are closely related to and fluctuate with AD severity over time. Improved control of AD signs and symptoms, particularly itch, may secondarily improve mental health.

Longitudinal Course of Sleep Disturbance and Relationship With Itch in Adult Atopic Dermatitis in Clinical Practice.

BACKGROUND: Sleep disturbance (SD) is common in atopic dermatitis (AD). We examined the longitudinal course of SD and relationship with itch in AD patients. METHODS: A prospective, dermatology practice-based study was performed (N = 1295) where patients were assessed at baseline and follow-up visits. RESULTS: At baseline, 16.9% of the patients had severe SD based on Patient-Reported Outcomes Information System (PROMIS) SD T scores, 19.1% had difficulty falling asleep, 22.9% had difficulty staying asleep, and 34.2% had SD from AD. A total of 31.4% of the patients with difficulty staying asleep at baseline experienced persistent difficulties (for 3 follow-ups or more). Only 17.7% with baseline difficulty falling asleep had persistent disturbance. Despite significant fluctuation in sleep scores, SD generally improved over time. Of the patients facing baseline SD from AD, 31.5% experienced SD at the first visit, and only 12.3% experienced persistent SD at the second follow-up visit. Predictors of increased PROMIS sleep-related impairment T scores over time included baseline PROMIS sleep-related impairment T scores (0.74 [0.68-0.80]), having 3 to 6 nights of itch (2.22 [0.85-3.59]), and severe/very severe AD (4.40 [2.60-6.20]). CONCLUSIONS: A significant proportion of adult AD patients, particularly those with moderate-severe AD and frequent itch, had baseline SD. Although sleep scores generally improved over time, many patients experienced a fluctuating or persistent course.

Epidemiology of prurigo nodularis in England: a retrospective database analysis.

BACKGROUND: Prurigo nodularis is a debilitating skin condition that is classified as rare by the Genetic and Rare Diseases Information Center (GARD) and the National Organization for Rare Diseases (NORD). There are currently no estimates of the prevalence of prurigo nodularis in England. OBJECTIVES: We aimed to address this data gap by describing the epidemiology of prurigo nodularis in a representative dataset derived from the English National Health Service. METHODS: The study utilized data from the Clinical Practice Research Datalink linked to Hospital Episode Statistics inpatient data. Patients with a diagnosis of prurigo nodularis were selected by clinical code in the primary care or inpatient datasets. Case definition was based on a minimum of two distinct diagnoses to maximize specificity. Point prevalence was calculated for the midpoint of 2018 and incidence rates from 2008 to 2018 were presented. For those classified as incident cases, demographic and clinical characteristics were reported. In sensitivity analyses the case definition was modified to relax the multiple diagnosis criteria and to restrict cases to those diagnosed within a maximum of 4 or 10 years of the midpoint prevalence date. RESULTS: Overall, 11 656 patients within the dataset had at least one prurigo nodularis diagnosis. Following application of the relevant inclusion criteria, 2743 patients formed the point prevalent cohort; the estimated prevalence was 3·27 patients per 10 000 population [95% confidence interval (CI) 3·15-3·40]. In sensitivity analyses the estimated prevalence ranged from 2·24 (95% CI 2·14-2·34) to 6·98 (95% CI 6·80-7·16). Incidence over the study period was 2·88 per 100 000 patient-years. Comorbidity was relatively high in this population, notably for atopic dermatitis (52·2%), depression (41·1%) and anxiety (35·4%). CONCLUSIONS: This study supports the NORD/GARD classification of prurigo nodularis as a rare disease with a prevalence of 3·27 patients per 10 000 population, which equates to 18 471 patients living with the disease in England in 2018. The relatively high prevalence of comorbidity observed for these patients may increase the complexity of management.

A real-world study of the longitudinal course of itch severity and frequency in adults with atopic dermatitis.

Itch is a complex symptom that is both common and burdensome in atopic dermatitis (AD). Yet, little is known about the longitudinal course of itch in AD. A prospective, dermatology practice-based study was performed of adults with AD (n = 463). Patients were assessed at baseline and approximately 6, 12, 18 and 24 months. Itch was assessed using Numeric Rating Scale (NRS) average and worst-itch scores, and frequency of itch in the past week. Repeated-measures regression models were constructed to examine itch over time. Overall, 31.5% and 22.5% had moderate (4-6) or severe (7-10) NRS average-itch scores; 27.4% and 36.4% had moderate (4-6) or severe (7-10) NRS worst-itch scores; 12.7% and 62.0% had itch from eczema 3-4 and ≥ 5 days in the past week; 27.4% and 45.1% reported sometimes and often/almost always having itch, respectively. Among patients with baseline moderate (4-6) or severe (7-10) NRS average-itch scores, 21.2% and 16.3% continued to have moderate or severe scores at ≥ 1 follow-up visits. In repeated-measures regression models, persistent NRS average-itch scores were associated with baseline NRS average-itch [adjusted ß (95% CI): 0.75 (0.68, 0.82)] and food allergy [- 0.45 (- 0.84, - 0.07)]. Persistent NRS worst-itch was associated with baseline worst-itch NRS [0.73 (0.66, 0.80)] and Medicaid insurance [1.06 (0.17, 1.94)]. AD patients had a heterogeneous longitudinal course with fluctuating and complex overlapping patterns of average- and worst-itch intensity, and frequency.

Health-related quality of life and economic burden of prurigo nodularis.

BACKGROUND: Prurigo nodularis (PN) is an understudied, pruritic inflammatory skin disease. Little is known about the effect of PN on quality of life and its associated economic burden. OBJECTIVE: To quantify the impact of PN on quality of life and its economic implications. METHODS: A cohort study of PN patients (n = 36) was conducted using the Health Utilities Index Mark 3 questionnaire. Control data from US adults (n = 4187) were obtained from the 2002-2003 Joint Canada/United States Survey of Health. Quality-adjusted life year loss and economic costs were estimated by comparing the Health Utilities Index Mark 3 scores of the PN patients with those of the controls. RESULTS: The PN patients had lower overall health performance compared to the controls, (mean ± SE, 0.52 ± 0.06 vs 0.86 ± 0.003, respectively, P < .001). In multivariable regression, PN was found to be associated with worse health performance (coefficient -0.34, 95% CI [-0.46 to -0.23]), most prominent in the pain subdomain (coefficient -0.24, 95% CI [-0.35 to -0.13]). This correlated to an average of 6.5 lifetime quality-adjusted life years lost per patient, translating to an individual lifetime economic burden of $323,292 and a societal burden of $38.8 billion. CONCLUSION: These results demonstrate that PN is associated with significant quality-of-life impairment, similar to the level of other chronic systemic conditions. PN is also associated with a substantial individual economic burden, emphasizing the necessity of research on effective treatment options.

Clinical phenotyping of atopic dermatitis using combined itch and lesional severity: A prospective observational study.

BACKGROUND: Patients with atopic dermatitis (AD) have heterogeneous clinical phenotypes, including different combinations of itch and lesional severity. Little is known about the characteristics and course of these subtypes. OBJECTIVE: To determine the characteristics, associations, burden, and course of patients with AD using combined itch and lesional severity. METHODS: A prospective practice-based study was performed using questionnaires and physical examination (n=592). AD subsets were defined using verbal rating scale for average itch combined with either eczema area and severity index, objective-scoring atopic dermatitis (SCORAD), or validated investigator's global assessment as follows: mild-moderate itch and lesions (MI-ML), mild-moderate itch and severe lesions (MI-SL), severe itch and mild-moderate lesions (SI-ML), and severe itch and lesions (SI-SL). RESULTS: At baseline, there were only weak-moderate correlations of numerical rating scales for worst itch or average itch or SCORAD itch with eczema area and severity index, objective-SCORAD, body surface area, and validated investigator's global assessment (Spearman's rho = 0.32-0.62). Most patients had MI-ML (59.4%-62.3%), followed by SI-ML (21.3%-29.1%), SI-SL (6.0%-12.9%), and MI-SL (3.8%-6.4%). Patients with SI-SL, followed by SI-ML and MI-SL, described their AD as being more severe overall and had worse impairment in sleep, mental health, and quality of life. However, those with MI-SL or SI-SL were far more likely to be classified as severe by a physician (multivariable logistic and linear regression, P < .005 for all). Baseline MI-SL, SI-ML, and SI-SL were associated with similar longitudinal courses over time and more AD flares and itch triggers than MI-ML. CONCLUSION: Combined itch and lesional severity seem to describe unique AD phenotypes. Further studies are needed to confirm these findings and understand the optimal treatments for these groups.

Reliability and Longitudinal Course of Itch/Scratch Severity in Adults With Atopic Dermatitis.

BACKGROUND: Itch is a complex and burdensome symptom in atopic dermatitis (AD). Severity of scratching/excoriation (SCORAD-scratch) has been found to be a valid measure of itch in AD. However, little is known about the longitudinal course of scratching/excoriations in AD. METHODS: A prospective, dermatology practice-based study was performed of adults with AD (N = 399). The patients were assessed at baseline and approximately 6, 12, 18, and 24 months. RESULTS: Severity of excoriations correlated best with the Numerical Rating Scale-worst itch (Spearman correlation, ρ = 0.50), followed by a Patient-Reported Outcome Measurement Information System Itch Questionnaire-scratching behavior T score (ρ = 0.48), Numerical Rating Scale-average itch (ρ = 0.41), relative frequency of itch (ρ = 0.36), and frequency of itch from eczema (ρ = 0.29, all P < 0.0001). Scratching severity showed good reliability (intraclass correlation coefficient range = 0.62-0.69). Overall, 30.6% and 5.5% had moderate (2) or severe (3) SCORAD-scratch scores. Among patients with baseline moderate (2) or severe (3) SCORAD-scratch scores, 18.9% and 13.6% continued to have moderate or severe scores at 1 or more follow-up visits. In repeated-measures regression models, persistent SCORAD-scratch scores were associated with baseline severity of excoriations (adjusted ß [95% confidence interval] = 0.51 [0.37 to 0.65]), Medicaid insurance (-0.35 [-0.65 to -0.04]), and Eczema Area and Severity Index scores (0.03 [0.02 to 0.04]). CONCLUSIONS: Adult AD patients had a heterogeneous longitudinal course with fluctuating severity of excoriations.

Validity and reliability of Patient-Reported Outcomes Measurement Information System Global Health scale in adults with atopic dermatitis.

BACKGROUND: Patient-Reported Outcomes Measurement Information System Global Health (PGH) was validated to assess health-related quality of life in several diseases. Little is known about its measurement properties in adult atopic dermatitis. OBJECTIVE: Examine the measurement properties of PGH in adult atopic dermatitis. METHODS: A prospective dermatology practice-based study of 994 atopic dermatitis patients (18-97 years). RESULTS: PGH physical and mental health 4-item and abridged 2-item T scores, as well as mapped EuroQol-5D score, showed strong to very strong correlation with one another and moderate to strong Spearman correlations with Patient-Oriented Scoring Atopic Dermatitis, Patient-Health Questionnaire-9, Patient-Reported Outcomes Measurement Information System sleep disturbance and related impairment, Eczema Area and Severity Index, objective Scoring Atopic Dermatitis; and weak to moderate correlations with Patient Oriented Eczema Measure, numeric rating scale worst itch and average itch, and Scoring Atopic Dermatitis. The Dermatology Life Quality Index (DLQI) had stronger correlations with Patient Oriented Eczema Measure, Patient-Oriented Scoring Atopic Dermatitis, numeric rating scale worst itch and average itch, Eczema Area and Severity Index, and Scoring Atopic Dermatitis, but weaker correlations with Patient-Health Questionnaire-9 and Patient-Reported Outcomes Measurement Information System sleep disturbance and related impairment (convergent/divergent validity). PGH and DLQI scores had similarly poor ability to differentiate between levels of self-reported global atopic dermatitis severity (known-groups validity). No floor or ceiling effects were observed. No PGH or DLQI items had differential item functioning by demographics. PGH and DLQI scores showed fair to good responsiveness. Finally, PGH and DLQI showed similarly good test-retest reliability. LIMITATIONS: Single-center study. CONCLUSION: PGH scores had sufficient validity and reliability to assess health-related quality of life in atopic dermatitis.

Measurement Properties of Patient Health Questionnaire 9 and Patient Health Questionnaire 2 in Adult Patients With Atopic Dermatitis.

BACKGROUND: Few outcome measures were validated for assessing depressive symptoms in AD. Patient Health Questionnaire-9 (PHQ9) and the abridged PHQ2 are established patient-reported outcome measures of depressive symptoms. OBJECTIVE: We sought to examine the measurement properties of PHQ9 and PHQ2 in adult AD. A prospective dermatology-practice based study of 458 AD patients (age 18-97 years) was conducted. RESULTS: PHQ9 strongly correlated with Dermatology Life Quality Index, Patient-Reported Outcomes Measurement Information System (PROMIS) Sleep-Disturbance and Sleep-Related Impairment, and PROMIS Itch Questionnaire Mood and Sleep (PIQ-MS), and moderately correlated with Patient-Oriented Eczema Measure, Numeric Rating Scale (NRS) average-itch, NRS-sleep, Eczema Area and Severity Index, Scoring AD and Rajka-Langeland scores. PHQ2 had significantly weaker correlations than PHQ9 with PROMIS SD, SRI and PIQ-MS, but similar correlations with other outcomes. PHQ9 and PHQ2 had good discriminant validity. Changes from baseline in PHQ9 and PHQ2 were poorly or weakly correlated with changes of the other outcome measures. There was no differential item functioning of PHQ items. PHQ9 showed good reliability (intraclass correlation coefficient range: 0.80-0.87). PHQ2 had slightly lower reliability (0.76-0.82). CONCLUSIONS: PHQ9 and PHQ2 had similar measurement properties, but PHQ2 was more feasible to assess depressive symptoms in AD.

Pathophysiology, diagnosis, and pharmacological treatment of prurigo nodularis.

Introduction: Prurigo nodularis (PN) is a chronic inflammatory skin disease characterized by intensely pruritic, hyperkeratotic nodules distributed on the trunk and extensor surfaces of the extremities. PN has a profoundly negative impact on sleep and quality of life in patients with PN. There are currently no U.S. Food and Drug Administration-approved agents and patients are often recalcitrant to current therapies, highlighting the importance of further research into this severely debilitating condition. Areas covered: A PubMed search was conducted to find available literature on the pathophysiology and clinical management of PN. In this review article, we discuss the current understanding of the pathophysiology, recommended diagnostic approach, and treatment options available for PN. Expert opinion/commentary: PN is an extremely difficult condition to treat, because there is a lack of effective therapies available due to our limited understanding of its pathophysiology. Currently, available treatment options are often multimodal due to the intersection of neuroimmune etiologic factors in the pathogenesis of PN. Fortunately, as our knowledge of PN expands, novel treatments targeting specific molecular biomarkers of PN are emerging, providing hope to this long-suffering patient population.