Efficacy and safety of on-demand versus daily rupatadine in chronic spontaneous urticaria: A randomized trial.

BACKGROUND: Non-sedating H1 -antihistamines (nsAH) are the most commonly used treatment for chronic spontaneous urticaria (CSU). Many patients use them as on-demand (OD) therapy rather than a maintenance treatment. Here, we compared OD versus daily maintenance treatment with the nsAH rupatadine, assessed the efficacy of rupatadine updosing, and investigated potential long-term disease-modifying effects. METHODS: This multicenter, randomized study consisted of 2 weeks of screening, 8 weeks of double-blind treatment, and 6 weeks of treatment-free follow-up (OD allowed). Adult patients were randomized to 10 mg rupatadine OD or 10 mg rupatadine daily. At Week 4, if patients did not have a complete response, they switched from 10 to 20 mg rupatadine daily or underwent sham updosing (patients on 10 mg rupatadine OD). The primary aim was to compare CSU disease activity at the end of follow-up between daily versus OD. Additionally, we assessed the efficacy of rupatadine updosing. Major outcomes were disease activity, CSU-related quality of life (QoL), and disease control. RESULTS: At Week 4, disease activity and QoL significantly improved in daily versus OD-treated patients. Updosing of rupatadine did not improve the mean disease activity, but the number of complete responders increased during updosing from 5% to 22%. At the end of follow-up, the disease activity of patients treated OD versus daily was not significantly different. CONCLUSIONS: Daily rupatadine treatment significantly improved CSU disease activity and QoL during treatment versus OD treatment but not after discontinuation of rupatadine, indicating the benefits of a daily maintenance nsAH schedule.

The 7-day recall period version of the Urticaria Control Test-UCT7.

BACKGROUND: The Urticaria Control Test (UCT) is a well-established, very easy to use and calculate 4-item patient-reported outcome measure to assess chronic urticaria disease control during the previous 4 weeks. Clinical trials and practice may benefit from the use of a UCT version with a shorter recall period, but this does not exist. OBJECTIVES: We sought to develop and validate a UCT version with a 7-day recall period, the UCT7. METHODS: The UCT7 was developed, based on the UCT, and tested, in 152 patients with chronic urticaria (spontaneous: n = 101, inducible: n = 51) for its reliability, validity and screening accuracy, and clinimetric properties, in other words, the cutoff for well-controlled disease and the minimal clinically important difference. RESULTS: The UCT7 showed excellent internal consistency reliability with a Cronbach αvalue of 0.91 and test-retest reliability with an intraclass correlation coefficient of 0.83. Convergent validity was high and strongly correlated with anchors of disease control, wheal and angioedema frequency, and urticaria-related quality of life impairment. The UCT7 showed excellent sensitivity to change; however, changes in angioedema activity and impact did not correlate well with changes in UCT7. Based on receiver-operating characteristic curve analysis, the proportion of correctly classified patients, and patients' assessment of treatment efficacy, we recommend a cutoff value of 12 points for identifying patients with well-controlled disease. The UCT7 minimal clinically important difference for improvement was estimated to be 2 points. CONCLUSIONS: The UCT7 is a validated 7-day recall period version of the UCT. It is ideal for the assessment of disease control at short intervals in patients with chronic urticaria in clinical studies and practice.

Long-term lanadelumab treatment improves health-related quality of life in patients with hereditary angioedema.

BACKGROUND: Hereditary angioedema (HAE) is associated with a substantial disease burden. Lanadelumab reduced the HAE attack rate during 132 weeks of follow-up in the HELP open-label extension (OLE) Study (NCT02741596). OBJECTIVE: To measure the impact of long-term lanadelumab treatment on patient-reported outcomes (PROs). METHODS: Rollover patients (completed the 26-week HELP study [NCT02586805]) and nonrollovers (newly enrolled) received lanadelumab 300 mg every 2 weeks. PROs (Angioedema Quality of Life Questionnaire [AE-QoL], Short Form Health Survey 12-item version 2, Hospital Anxiety and Depression Scale, Work Productivity and Activity Impairment-General Health Questionnaire, and EQ-5D-5L questionnaire) were assessed at baseline (day 0 of HELP OLE) and various time points until the end-of-study visit. The Angioedema Control Test, Treatment Satisfaction Questionnaire for Medication, and Global Impression of Treatment Response were administered starting at week 52. RESULTS: The mean (SD) change in AE-QoL total score from baseline to end-of-study for rollovers (n = 90) was -10.2 (17.9), exhibiting further improvement from HELP in health-related quality of life (HRQoL); 48.9% of rollovers achieved the previously defined 6-point minimal clinically important difference. Nonrollovers (n = 81) reported a change of -19.5 (21.3). Controlled disease (Angioedema Control Test total score ≥10) was reported by 90.2% of rollovers and 95.9% of nonrollovers at the end of the study. Excellent treatment response was reported by 78.7% of patients and 82.4% of investigators. Results from other PROs indicated a slight improvement in anxiety, a high level of satisfaction with treatment, and increased work productivityor activity. CONCLUSION: Clinically meaningful improvement in HRQoL was exhibited with long-term lanadelumab treatment, supporting the benefit of lanadelumab therapy associated with attack prevention. TRIAL REGISTRATION: ClinicalTrials.gov Identifiers: NCT02586805 (HELP Study) and NCT02741596 (HELP open-label extension).

Association of Chronic Urticaria with Psychological Distress: A Multicentre Cross-sectional Study.

Chronic urticaria is a debilitating disease that affects health-related quality of life, but few studies have evaluated its impact on psychological wellbeing. The aim of this study was to evaluate the quality of life of patients with chronic urticaria and determine its impact on their emotional and psychological wellbeing. A cross-sectional multicentre study of a cluster of 264 Lebanese patients visiting dermatology/immunology clinics was conducted between July 2018 and June 2020. The impact of chronic urticaria on quality of life was assessed using the Chronic Urticaria Quality of Life Questionnaire (CU-Q2oL) and Dermatology Life Quality Index (DLQI), as well as its consequences on mood changes using the Patient Health Questionnaire-9 (PHQ-9) and Beirut Distress Score 22 (BDS-22) scores. A multivariable analysis of covariates was performed to determine the effect of the triggering factors of urticaria on both CU-Q2oL and PHQ-9. A moderate negative correlation was found between Urticaria Control Test and quality of life scores as well as PHQ-9 and BDS-22 (p < 0.001). Patients with the lowest Urticaria Control Test score had the highest impairment in quality of life and depression scores. In conclusion, chronic urticaria compromises patients' quality of life and emotional wellbeing. This distress is more pronounced when the disease is more severe.

The validity and reliability of a Thai version of the Angioedema Control Test: Which recall period is preferable?

BACKGROUND: The Angioedema Control Test (AECT) is a questionnaire that monitors disease control in patients with angioedema, with a recall period of 4 weeks (AECT-4wk) or 3 months (AECT-3mo). OBJECTIVE: This study investigated the psychometric properties of a Thai version of the AECT. METHODS: Of 54 patients, 46, 5, 2, and 1 had recurrent angioedema with chronic spontaneous urticaria, hereditary angioedema, idiopathic histaminergic angioedema, and acquired angioedema due to C1 esterase inhibitor deficiency, respectively. The AECT, Angioedema Activity Score (AAS), Dermatology Life Quality Index (DLQI), Angioedema Quality of Life Questionnaire (AE-QoL), and anchors for disease control (numeric rating scale [NRS] and patient global assessment-Likert scale [PatGA-LS]) were used. The patients rated the efficacy of their treatment. RESULTS: Fifty-four and 47 patients completed the AECT-4wk and AECT-3mo, respectively. Both AECT versions showed significant correlations with disease activity (AAS, r = 0.6-0.8), disease control (NRS and PatGA-LS, r = 0.7-0.9), and quality of life impairment (DLQI and AE-QoL, r = 0.6-0.8). Higher correlations were found for the AECT-4wk than for the AECT-3mo. Excellent internal consistency (alpha = 0.98 and 0.97, respectively) and intraclass correlation (0.96 and 0.94, respectively) were found. A cutoff ≥ 10 was confirmed to identify patients with well-controlled disease for both AECT versions (AUCs = 0.89 and 0.97). CONCLUSIONS: The Thai version of the AECT is a valid and reliable tool for clinical practice. Due to the shorter recall period, the AECT-4wk may be more accurate than, and preferable to, the AECT-3mo. A cutoff ≥ 10 should be used to identify patients with well-controlled disease.

CRUSE - What the first 100 days have taught us.

Introduction: Health apps play an increasing role in everyday healthcare, especially for chronic diseases. The Chronic Urticaria Self Evaluation (CRUSE) is a new mobile health app for chronic spontaneous urticaria (CSU) patients, which replaces disease tracking via paper and pen, thus making disease monitoring more convenient, increasing tracking compliance, and improving data quality and access. Methods: CRUSE enables patients to complete patient-reported outcome measures on their smartphone and send the results, along with current medication and pictures, to their treating physician via email. CRUSE captures the urticaria (UAS) and angioedema activity (AAS) scores and the urticaria and angioedema control tests (UCT and AECT). In this work, a descriptive analysis of CRUSE users and reported days was performed. The global network of Urticaria Centers of Reference and Excellence (UCARE) provides the app and its data. Results: CRUSE is now available in Germany, Switzerland, Austria, the UK, Italy, Spain, France, and Turkey. Of 620 newly registered users (from July 1st until November 18th of 2022), 72 % were female, and the mean age was 36.6 years (17 - 78 years). The average daily UAS and AAS value (mean ± standard deviation) were 2.1 ± 1.9 and 7.2 ± 3.3, respectively. Most CRUSE patients had poorly controlled disease, with mean UCT values of 7.0 ± 4.4 and mean AECT values of 8.1 ± 4.5. Conclusion: The first days of patients with CSU using CRUSE confirm the high need for an app that helps to monitor disease activity, impact, and control. The first results indicate low levels of disease control in most CRUSE users, with low UCT and AECT values. Future analyses will assess follow-up documentation data and evaluate the effects of treatment changes on CSU activity, impact, and control.

Development of the Cold Urticaria Activity Score.

BACKGROUND: Cold urticaria (ColdU) is a form of inducible urticaria where cold induces wheals and/or angioedema. The burden of disease is high and linked to trigger thresholds, exposure, and avoidance. There are presently no validated patient-reported outcome measures (PROMs) to assess and monitor disease activity. Our objective was to develop a disease-specific activity score for ColdU that is easy to administer and evaluate. METHODS: A Cold Urticaria Activity Score (ColdUAS) questionnaire was developed, directed by PROM developing guidelines. After the generation of a conceptional framework, the item generation phase included the literature research on ColdU signs and symptoms and on comparable tools for similar diseases and 47 ColdU patient interviews. Subsequently, an impact analysis for content validity was performed. The final selection of items underwent expert review for face validity and cognitive debriefing. RESULTS: The ColdUAS, a self-administered questionnaire for the prospective assessment of disease activity in patients with ColdU, consists of 4 items: 1. the frequency and severity of the signs (wheals and/or angioedema), 2. the frequency and severity of the symptoms (e.g., itch and burn), 3. the exposure to specific triggers, and 4. the avoidance of these triggers. The recall period for each item is the last 24 h. CONCLUSIONS: The ColdUAS is the first disease-specific PROM to assess ColdU disease activity. It may help to better assess patients' disease status in routine clinical practice as well as in clinical trials. Anchor-based approaches are currently used to validate the ColdUAS.

Impact of lanadelumab on health-related quality of life in patients with hereditary angioedema in the HELP study.

BACKGROUND: An objective of the phase 3 HELP Study was to investigate the effect of lanadelumab on health-related quality of life (HRQoL) in patients with hereditary angioedema (HAE). METHODS: Patients with HAE-1/2 received either lanadelumab 150 mg every 4 weeks (q4wks; n = 28), 300 mg q4wks (n = 29), 300 mg every 2 weeks (q2wks; n = 27), or placebo (n = 41) for 26 weeks (days 0-182). The Angioedema Quality of Life Questionnaire (AE-QoL) was administered monthly, consisting of four domain (functioning, fatigue/mood, fears/shame, nutrition) and total scores. The generic EQ-5D-5L questionnaire was administered on days 0, 98, and 182. Comparisons were made between placebo and (a) all lanadelumab-treated patients and (b) individual lanadelumab groups for changes in scores (day 0-182) and proportions achieving the minimal clinically important difference (MCID, -6) in AE-QoL total score. RESULTS: Compared with the placebo group, the lanadelumab total group demonstrated significantly greater improvements in AE-QoL total and domain scores (mean change, -13.0 to -29.3; p < 0.05 for all); the largest improvement was in functioning. A significantly greater proportion of the lanadelumab total group achieved the MCID (70% vs 37%; p = 0.001). The lanadelumab 300 mg q2wks group had the highest proportion (81%; p = 0.001) and was 7.2 times more likely to achieve the MCID than the placebo group. Mean EQ-5D-5L scores at day 0 were high in all groups, indicating low impairment, with no significant changes at day 182. CONCLUSION: Patients with HAE-1/2 experienced significant and clinically meaningful improvements in HRQoL measured by AE-QoL following lanadelumab treatment in the HELP Study.

Sleep disturbance in adult dermatologic patients: A cross-sectional study on prevalence, burden, and associated factors.

BACKGROUND: Sleep disturbance remains insufficiently characterized in many dermatoses. OBJECTIVE: To investigate the prevalence, burden, and factors associated with sleep disturbance in dermatologic patients. METHODS: We recruited 800 patients and recorded pruritus characteristics and sociodemographic and clinical parameters. Validated questionnaires were used to assess sleep disturbance, psychological distress, health-related quality of life, and work productivity. RESULTS: Two thirds of patients met criteria of poor sleep, which was associated with psychological distress, diminished health-related quality of life, and lost work productivity. Patients with average and maximum pruritus on the visual analog scale exceeding 5 and 6.5 points, respectively, were at high risk of suffering pruritus-related sleep disturbance. Overall pruritus intensity and its nocturnal exacerbation contributed independently to sleep disturbance. Psychological distress was of even higher impact on sleep than pruritus and almost a third of the relationship between pruritus intensity and sleep was mediated by psychological distress. CONCLUSION: Sleep disturbance is prevalent in dermatologic patients and constitutes a considerable burden. CLINICAL IMPLICATION: Dermatologic patients with intense pruritus and psychological distress should be examined for sleep disorders. Adequate antipruritic therapy and complementary psychotherapy in affected patients may help them regain restorative sleep.

The characteristics and impact of pruritus in adult dermatology patients: A prospective, cross-sectional study.

BACKGROUND: Pruritus often accompanies chronic skin diseases, exerting considerable burden on many areas of patient functioning; this burden and the features of pruritus remain insufficiently characterized. OBJECTIVE: To investigate characteristics, including localization patterns, and burden of pruritus in patients with chronic dermatoses. METHODS: We recruited 800 patients with active chronic skin diseases. We assessed pruritus intensity, localization, and further characteristics. We used validated questionnaires to assess quality of life, work productivity and activity impairment, anxiety, depression, and sleep quality. RESULTS: Nine out of every 10 patients had experienced pruritus throughout their disease and 73% in the last 7 days. Pruritus often affected the entire body and was not restricted to skin lesions. Patients with moderate to severe pruritus reported significantly more impairment to their sleep quality and work productivity, and they were more depressed and anxious than control individuals and patients with mild or no pruritus. Suicidal ideations were highly prevalent in patients with chronic pruritus (18.5%) and atopic dermatitis (11.8%). CONCLUSIONS: Pruritus prevalence and intensity are very high across all dermatoses studied; intensity is linked to impairment in many areas of daily functioning. Effective treatment strategies are urgently required to treat pruritus and the underlying skin disease.

Patient-reported Outcome Measures for Angioedema: A Literature Review.

Angioedema and hereditary angioedema are characterized by swelling of the subcutaneous and/or submucosal tissue, resulting in localized oedema. The rarity, but also the diverse clinical presentation, of these conditions can be challenging regarding diagnosis, treatment, and management. Patient-reported outcome measures (PROMs) are data received directly from the patient, providing the patient's perspective on various subjects regarding health and well-being. PROMs can be helpful tools to optimize treatment and long-term management of conditions. A major challenge regarding the consistent use of PROMs in clinical settings in Scandinavia is language availability; many of the validated PROMs for hereditary angioedema and angioedema lack translations into the Nordic languages. The litterature search yielded 9 different PROM tools for angioedema and hereditary angioedema. Five were found suitable for use in clinical practice in Europe. Even though several PROMs exist they are not used consistent. Accessible electronic PROMs and careful planning is required to implement PROMs optimally in routine care processes.

Prevalence of chronic urticaria in children and adults across the globe: Systematic review with meta-analysis.

BACKGROUND AND OBJECTIVES: Urticaria is a frequent skin condition, but reliable prevalence estimates from population studies particularly of the chronic form are scarce. The objective of this study was to systematically evaluate and summarize the prevalence of chronic urticaria by evaluating population-based studies worldwide. METHODS: We performed a systematic search in PUBMED and EMBASE for population-based studies of cross-sectional or cohort design and studies based on health insurance/system databases. Risk of bias was assessed using a specific tool for prevalence studies. For meta-analysis, we used a random effects model. RESULTS: Eighteen studies were included in the systematic evaluation and 11 in the meta-analysis including data from over 86 000 000 participants. Risk of bias was mainly moderate, whereas the statistical heterogeneity (I2 ) between the studies was high. Asian studies combined showed a higher point prevalence of chronic urticaria (1.4%, 95%-CI 0.5-2.9) than those from Europe (0.5%, 0.2-1.0) and Northern American (0.1%, 0.1-0.1). Women were slightly more affected than men, whereas in children < 15 years we did not find a sex-specific difference in the prevalence. The four studies that examined time trends indicated an increasing prevalence of chronic urticaria over time. CONCLUSIONS: On a global level, the prevalence of chronic urticaria showed considerable regional differences. There is a need to obtain more sex-specific population-based and standardized international data particularly for children and adolescents, different chronic urticaria subtypes and potential risk and protective factors.

Development of the Angioedema Control Test-A patient-reported outcome measure that assesses disease control in patients with recurrent angioedema.

BACKGROUND: Recurrent angioedema (AE) is an important clinical problem in the context of chronic urticaria (mast cell mediator-induced), ACE-inhibitor intake and hereditary angioedema (both bradykinin-mediated). To help patients obtain control of their recurrent AE is a major treatment goal. However, a tool to assess control of recurrent AE is not yet available. This prompted us to develop such a tool, the Angioedema Control Test (AECT). METHODS: After a conceptional framework was developed for the AECT, a list of potential AECT items was generated by a combined approach of patient interviews, literature review and expert input. Subsequent item reduction was based on impact analysis, inter-item correlation, additional predefined criteria for item performance, and a review of the item selection process for content validity. Finally, an instruction section was generated, and an US-American-English version was developed by a structured translation process. RESULTS: A 4-item AECT with recall periods of 4 weeks and 3 months was developed based on 106 potential items tested in 97 patients with mast cell mediator-induced (n = 49) or bradykinin-mediated recurrent AE (n = 48). Eighty-four items were excluded based on impact analysis. The remaining 22 items could be further reduced by a method-mix of inter-item correlation, additional predefined criteria for item performance and review for content validity. CONCLUSIONS: The AECT is the first tool to assess disease control in recurrent AE patients. Its retrospective approach, its brevity and its simple scoring make the AECT ideally suited for clinical practice and trials. Its validity and reliability need to be determined in future independent studies.

Urticaria: Collegium Internationale Allergologicum (CIA) Update 2020.

This update on chronic urticaria (CU) focuses on the prevalence and pathogenesis of chronic spontaneous urticaria (CSU), the expanding spectrum of patient-reported outcome measures (PROMs) for assessing CU disease activity, impact, and control, as well as future treatment options for CU. This update is needed, as several recently reported findings have led to significant advances in these areas. Some of these key discoveries were first presented at past meetings of the Collegium Internationale Allergologicum (CIA). New evidence shows that the prevalence of CSU is geographically heterogeneous, high in all age groups, and increasing. Several recent reports have helped to better characterize two endotypes of CSU: type I autoimmune (or autoallergic) CSU, driven by IgE to autoallergens, and type IIb autoimmune CSU, which is due to mast cell (MC)-targeted autoantibodies. The aim of treatment in CU is complete disease control with absence of signs and symptoms as well as normalization of quality of life (QoL). This is best monitored by the use of an expanding set of PROMs, to which the Angioedema Control Test, the Cholinergic Urticaria Quality of Life Questionnaire, and the Cholinergic Urticaria Activity Score have recently been added. Current treatment approaches for CU under development include drugs that inhibit the effects of signals that drive MC activation and accumulation, drugs that inhibit intracellular pathways of MC activation and degranulation, and drugs that silence MCs by binding to inhibitory receptors. The understanding, knowledge, and management of CU are rapidly increasing. The aim of this review is to provide physicians who treat CU patients with an update on where we stand and where we will go. Many questions and unmet needs remain to be addressed, such as the development of routine diagnostic tests for type I and type IIb autoimmune CSU, the global dissemination and consistent use of PROMs to assess disease activity, impact, and control, and the development of more effective and well-tolerated long-term treatments for all forms of CU.

Validity, reliability, and interpretability of the Brazilian urticaria control test.

Background: The urticaria control test (UCT) is a patient-reported outcome measure designed to determine the current level of disease control in patients with chronic urticaria (CU). Recently, a Brazilian UCT was developed, but its validity and reliability are unknown. Method: The clinimetric properties of the Brazilian UCT short form (UCTsh) and its long form (UCTlg) were determined in 130 patients with CU. In parallel, the urticaria activity scores (UAS) that covers 7 days (UAS7) and 28 days (UAS28) were used to assess disease activity. Subsequently, the results were analyzed statistically to determine the validity, reliability, and interpretability of the Brazilian UCT versions. Results: A total of 107 female (82%) and 23 male patients with CU completed both versions of the Brazilian UCT. Both of the Brazilian UCT versions showed excellent internal consistency reliability. In addition, the Brazilian UCT results showed strong correlations with UAS7 and UAS28 results, which indicated high levels of convergent validity. The test-retest reliability was examined in a subsample of 27 patients with CU and was found to be excellent. Notably, the results of both Brazilian UCT versions correlated extensively, which suggested that the UCTsh can replace the UCTlg without changing the UCT results. Conclusion: The Brazilian UCT is a valid and reliable tool for assessing disease control. To facilitate the use of the Brazilian UCT in global studies and to put a stronger focus on the specificity, we propose that the same cutoff values for well-controlled disease should be used as identified in the original publication of the UCT, i.e., ≥12 points for the UCTsh.

Flare Size but Not Intensity Reflects Histamine-Induced Itch.

INTRODUCTION: Flare reactions arise due to the release of vasodilators from sensory nerves caused by antidromic transmission of action potentials after the induction of itch. OBJECTIVE: We investigated the link between flare and itch using 3 models of itch. METHODS: Skin provocations with histamine, capsaicin, and cowhage were performed in 31 subjects. Itch was quantified using the visual analog scale. Flare was assessed using laser speckle contrast imaging (LSCI) and digital photography. RESULTS: The duration, intensity, and area under the curve of histamine-induced itch correlated with the area of increased blood flow measured with LSCI (r = 0.545, p = 0.002; r = 0.575, p = 0.001; and r = 0.649, p < 0.001, respectively). Itch and skin blood flow in response to capsaicin or cowhage did not correlate. CONCLUSION: In histamine-induced skin inflammation, itch and increased blood flow are linked. Thus, the area of histamine-induced flare may be used as a surrogate marker for histamine-induced itch.

Navigating the landscape of core outcome set development in dermatology.

The development of core outcome sets (COSs; ie, a minimum set of core outcomes that should be measured and reported in all trials or in clinical practice for a specific condition) in dermatology is increasing in pace. A total of 44 dermatology-related COS projects have been registered in the online Core Outcome Measures in Effectiveness Trials database (http://www.comet-initiative.org/studies/search) and include studies on 26 different skin diseases. With the increasing number of COSs in dermatology, care is needed to ensure the delivery of high-quality COSs that meet quality standards when using state-of-the-art methods. In 2015, the Cochrane Skin-Core Outcome Set Initiative (CS-COUSIN) was established. CS-COUSIN is an international, multidisciplinary working group aiming to improve the development and implementation of COSs in dermatology. CS-COUSIN has developed guidance on how to develop high-quality COSs for skin diseases and supports dermatology-specific COS initiatives. Currently, 17 COS development groups are affiliated with CS-COUSIN and following standardized COS development processes. To ensure successful uptake of COSs in dermatology, researchers, clinicians, systematic reviewers, guideline developers, and other stakeholders should use existing COSs in their work.

Angioedema quality of life questionnaire (AE-QoL) - interpretability and sensitivity to change.

BACKGROUND: The Angioedema Quality of Life (AE-QoL) is the first patient reported outcome measure developed for the assessment of quality of life (QoL) impairment in patients with recurrent angioedema (RAE). This study aimed to evaluate the clinimetric properties of the AE-QoL in Thai patients and to establish categories of QoL impairment assessed by the AE-QoL. METHODS: The validated Thai version of the Dermatology Life Quality Index (DLQI) and Patient Global Assessment of Quality of Life (PGA-QoL) were used to comparatively evaluate the Thai version of AE-QoL. Spearman correlations between the Thai AE-QoL and two other standard measurements (DLQI and PGA-QoL) were investigated to determine convergent validity. The Thai DLQI and PGA-QoL were used to categorize patients according to their QoL. Known-group validity of the Thai AE-QoL was later analyzed. The reliability of the Thai AE-QoL was investigated using Cronbach's alpha and intraclass correlation. Three different approaches including the distribution method, receiver operating characteristic curve analysis, and the anchor based-method were used for the interpretability. RESULTS: A total of 86 patients with RAE with a median age of 38.0 ± 15.1 years (range 18-76) were enrolled. Of those, 76 patients (88%) had RAE with concomitant wheals, and 10 patients (11.6%) had RAE only. The AE-QoL assessed RAE-mediated QoL impairment with high convergent validity and known-groups validity, high internal consistency and test-retest reliability, and good sensitivity to change. Although the AE-QoL did not differentiate between patients with moderate and large effect as measured by PGA-QoL or DLQI in this study, AE-QoL total values of 0-23, 24 to 38, and ≥ 39 could define patients with "no effect", "small effect", and "moderate to large effect" of RAE on their QoL, respectively. CONCLUSIONS: This study supports the validity and reliability of the Thai version of the AE-QoL, which is a very different language from the original version. Categories allow to classify the effect of RAE on patients' QoL as "none", "small", and "moderate to large". Further studies are needed to confirm the applicability of AE-QoL in other Asian populations".