Amit Garg

Background: The 2015 core domain set (CDS) for vitiligo defines outcomes for clinical trials, comprising three essential and four recommended outcome domains/domain items. Periodic reassessment is required to ensure its continued relevance. Objectives: To evaluate the content validity (relevance, comprehensiveness and comprehensibility) of the 2015 vitiligo CDS to inform a consensus-based update as part of a core outcome set, including core outcomes and core measurement instruments. Methods: A roundtable discussion and three surveys reassessed the 2015 vitiligo CDS regarding relevance (≥ 70% agreement for ‘essential’), comprehensiveness (identification of missing domain items) and comprehensibility (clarity of terminology and descriptions). Results: Fifty-three patients with vitiligo (group 1) and 37 experts (36 dermatologists and 1 researcher; group 2) participated. Two previously essential domains (‘Repigmentation’ and ‘Side effects/harms’) were re-endorsed as essential by both groups. ‘Maintenance of gained repigmentation’ was rated essential by patients only. Among previously recommended domains, ‘Quality of life’ was considered essential by both groups, whereas ‘Cosmetic acceptability of repigmentation’ and ‘Cessation of spreading of vitiligo’ were rated essential by patients only. ‘Tolerability/burden of treatment’ was not considered essential by either group. Frequently suggested missing items (outcomes and contextual factors) included psychological impact, treatment session duration, overall treatment duration, treatment costs, patient education and evaluation of associated auto­immune diseases. Proposed updates included refining domain terminology (e.g. vitiligo-specific/health-related quality of life; replacing ‘harms’ with ‘adverse events’) and addressing feasibility-related timeframes. Conclusions: While the 2015 vitiligo CDS retains content validity for several domains, meaningful updates are warranted. These findings will inform the development of a revised and updated CDS.

Background: Hidradenitis suppurativa (HS)-specific quality of life (QOL) is one of six core domains for HS studies defined by HIdradenitis SuppuraTiva cORe outcomes set International Collaboration (HISTORIC). The 17-item Hidradenitis Suppurativa Quality of Life (HiSQOL©) questionnaire was developed and validated by HISTORIC to measure this domain. A shortened version would be easier for routine clinical use. Objectives: To produce a shortened version of HiSQOL by selecting a subset of the original 17 items. Methods: Item selection for HiSQOL-mini was informed by correlation analyses on two datasets from the Treatment of Hidradenitis Suppurativa Evaluation Study (THESEUS) and the BE HEARD I and II Phase 3 trials. Spearman’s rank correlation coefficients were calculated between each item and the HiSQOL total score after omitting that item. Two consensus workshops were then conducted, with patient research partners (PRPs) leading the discussions, to finalise the items for inclusion. Analyses to assess psychometric performance and derive interpretation thresholds for HiSQOL-mini were conducted using the BE HEARD dataset. Results: In the symptoms sub-domain, pain exhibited the highest correlation with HiSQOL total score and was unanimously selected at the end of Workshop 1. In the psychosocial sub-domain, the ‘down or depressed’ item performed best from THESEUS data, while the ‘concentration’ and ‘embarrassed’ items performed best from BE HEARD data. Related to content validity, PRPs prioritised ‘down or depressed’ in the discussions. ‘Walking’ performed well in both datasets and PRPs further recommended inclusion of a second activities-adaptations item, ‘getting dressed’. HiSQOL-mini demonstrated good validity, reliability and responsiveness, and has scores ranging from 0–16. Minimal important difference was a 3-point reduction and clinically meaningful change was a 5-point reduction. Severity thresholds for HiSQOL-mini score were 0 for ‘none’, 1–2 for ‘mild’, 3–4 for ‘moderate’, 5–6 for ‘severe’ and 7–16 for ‘very severe’. Conclusions: HiSQOL-mini, using the same item format as HiSQOL, contains four items relating to ‘pain’, feeling ‘down or depressed’, ‘walking’ and ‘getting dressed’. HiSQOL-mini is a valid, reliable and responsive questionnaire to measure health-related QOL in patients with HS and should be swift to perform.

Introduction The risk of thromboembolism in patients with hidradenitis suppurativa (HS) has not been established. This study aimed to estimate the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) among adults with HS and demographic subgroups. Methods This retrospective cohort study was conducted between January 1, 2017, and December 31, 2024, using a health insurance claims database (Optum Clinformatics DataMart) in the US. Adults aged ≥ 18 years with an outpatient visit linked to a diagnosis of HS or any other diagnosis (controls) were eligible. Patients with prior diagnosis of either outcome or associated conditions were excluded. The primary outcomes evaluated were new-onset DVT and PE. Results Mean (SD) age was 43 (16) years for eligible patients with HS (n = 44,520) and 54 (19) years for control patients (n = 3,792,627). Incidence of DVT was 3.0 (95% CI 2.5–3.4) and 3.5 (95% CI 3.4–3.5) per 1000 person-years (PY) in patients with HS and controls, respectively. Incidence of PE was 2.4 (95% CI 2.0–2.8) and 2.2 (95% CI 2.2–2.3) per 1000 PY in patients with HS and controls, respectively. In demographics-adjusted analyses, standardized incidence ratios for DVT and PE were 1.42 (95% CI 1.23–1.65) and 1.78 (95% CI 1.50–2.10), respectively. Comorbidity-adjusted hazard ratios for DVT and PE were 1.12 (95% CI 0.97–1.31) and 1.35 (95% CI 1.14–1.60), respectively. Incidence of DVT was higher in patients with HS by a factor of 1.5–2.9 for age subgroups between 45 and 74 years, with absolute incidence rates ranging from 3.5 to 8.8 per 1000 PY. Incidence of PE was higher in patients with HS by a factor of 1.5–3.2 across age subgroups between 45 and 74 years, with absolute incidence rates ranging from 3.0 to 5.4 per 1000 PY. Conclusion Patients with HS have a significantly higher incidence of both DVT and PE relative to demographically similar patients without HS. This information may support counseling on risk mitigation strategies and safety monitoring during treatment and may provide context for observed (versus expected) thrombotic events in clinical trials for HS.

Introduction: Patients with hidradenitis suppurativa (HS) receive limited dermatologic care even though timely care is essential to minimize disease morbidity and progression. This retrospective cohort study examined whether clinical encounter setting and patient demographics were associated with outpatient dermatology follow-up among patients with HS. Methods: Adults (≥18) from two health systems in a large southern US metropolitan area with ≥2 clinical encounters from 9/10/2014 to 10/9/2020 and a diagnosis of HS at ≥ 1 visit were included. Outcomes included any outpatient dermatology visit and encounter setting-specific probabilities of outpatient dermatology as the next encounter. Results: A total of 3,336 participants (77.7% Black, 72.8% female) with 9,724 HS-related encounters were included. Outpatient care was received by 288/1,364 (21.1%) of participants in the public system and 167/1,972 (8.5%) in the private system. Few emergency department, inpatient, and ambulatory surgery encounters were followed by dermatology visits (2.8%, 2.7%, and 3.9%, respectively). The odds of dermatology care were lowest following emergency department encounters (aOR: 0.43, 95% CI: 0.30–0.61), inpatient hospitalization (aOR: 0.41, 0.27–0.63), and ambulatory surgery (aOR: 0.44, 0.21–0.89) compared to primary care. Patients seen most frequently in these settings had the lowest probability of any dermatology encounters during the study period (9.1% [95% CI: 6.4–11.8%], 6.7% [3.9–9.4%], and 9.1% [1.5–16.7%], respectively). In the private system, patients with commercial insurance (aHR: 3.34, 1.78–6.23) and Medicare (aHR: 4.12, 95% CI: 2.00–8.51) were more likely to receive dermatology care than those with Medicaid. Patients who were white (aHR: 0.60, 0.39–0.93) or male (aHR: 0.58, 0.36–0.93) were less likely to receive dermatology care. In the public system, the hazard of receiving outpatient dermatologic care did not differ by demographic characteristics. Conclusions: Few patients with HS had an outpatient dermatology encounter, with particularly low follow-up among patients with Medicaid in the private healthcare system. High-acuity settings were associated with lower odds of outpatient follow-up. Interventions that improve follow-up among patients seen in high-acuity settings such as the emergency department or inpatient units may reduce morbidity, disease progression, and future need for emergency care among patients with severe disease.

Inconsistent outcome selection and measurement remain major barriers to evidence synthesis in dermatology. We introduce the CHORD COUSIN Collaboration (C3) Manual and Checklist, developed through an international collaborative process, which consolidates existing methodological guidance into a structured, practical framework to support the development and implementation of core outcome sets. By improving standardization and providing methodological support, C3 aims to enhance comparability across studies and strengthen dermatological research.

To date, the primary endpoint of hidradenitis suppurativa (HS) clinical trials is typically a focused lesion count, which has been shown to be error prone and which may not comprehensively measure the inflammatory burden. Unlike lesions of other inflammatory skin diseases such as atopic dermatitis, vitiligo and alopecia areata, HS lesions exhibit substantial morphological heterogeneity. Accordingly, the Investigator Global Assessment of Hidradenitis Suppurativa (I-GLASS) instrument was developed.

Repigmentation is an essential outcome in vitiligo assessment, yet it remains broadly defined. While perspectives from vitiligo experts have been explored, gaining insights from patients is crucial for a more comprehensive understanding. Ultimately, this could contribute to the development and refinement of core outcome sets for vitiligo. This study aimed to determine aspects of repigmentation patients consider most important. Two surveys and one focus group were conducted, involving 34 patients/patient caregivers and 20 patient representatives. In the surveys, aspects were deemed important if ≥ 70% of participants rated them as such. The focus group used the nominal group technique to rank the five most important self‐suggested aspects. The survey results indicate reduction of target lesion surface area, maintenance of repigmentation, and cessation of spread as important. The focus group identified additional aspects, including “time to repigment,” “location of lesions,” and “color match”. This study identified key aspects of repigmentation important to vitiligo patients. While survey results in general aligned with the core domain set for vitiligo clinical trials, the focus group highlighted additional factors. Incorporating these patient‐centered priorities into future core outcome sets could enhance the clinical relevance of vitiligo research and ensure outcomes reflect patient perspectives.

Background: Hidradenitis suppurativa (HS) is a chronic, debilitating inflammatory skin condition often accompanied by malodorous drainage. Drainage affects quality of life, contributing to stigma, emotional distress, and physical challenges. Recognising the role of drainage in HS, the HiSTORIC (Hidradenitis SuppuraTiva cORe outcomes set International Collaboration) initiative identified it as a key symptom in clinical trials and developed the The HIdradenitis suppurativa DrainagE (HIDE) Scale. Objectives: This study aimed to explore patients' experiences of drainage to guide person‐centred care approaches. Methods: A qualitative secondary analysis was conducted using data from the parent study on The HIDE Scale ^©️ . The data included 38 interviews with patients aged ≥ 18 years, diagnosed with HS, and experiencing drainage. Reflexive thematic analysis was applied using an inductive and semantic approach, guided by person‐centred theoretical perspectives. Results: Three overarching themes emerged: (1) Drainage is difficult to explain due to its unpredictable and complex nature; (2) Drainage impacts mental well‐being , contributing to feelings of social stigma, frustration, and emotional distress; and (3) Drainage involves significant physical difficulties , including malodour, frequent dressing changes, and daily activity disruption. Patients described drainage by volume, consistency, colour, and location, emphasising its multidimensional impact. Despite these challenges, pain was identified as the most debilitating symptom of HS. Conclusions: This study highlights the physical, psychological, and social impact of drainage in HS, emphasising its complexity and unpredictability. Patients described drainage as a multifaceted experience that profoundly affects their quality of life. To improve care, healthcare providers should integrate an assessment of drainage into clinical practice, utilising standardised tools like The HIDE Scale ^©️ . Addressing physical and psychosocial aspects of drainage through open and empathetic discussions can reduce stigma, foster a sense of support, and enhance patient–clinician relationships. Adopting person‐centred approaches validates patients' experiences and holistic assessment is essential for improving care strategies and the well‐being of individuals living with HS.

Background: Hidradenitis suppurativa (HS) is an inflammatory skin condition that is associated with a prolonged diagnostic delay of approximately 7–10 years. The diagnostic delay can be attributed to various factors, including low awareness of diagnostic criteria among nondermatological healthcare professionals often leading to misdiagnosis. Screening questionnaires have been proposed for the diagnosis of HS. One such questionnaire has been validated and used in the Global Hidradenitis Suppurativa Atlas (GHiSA) Global Prevalence Study (GPS). Objectives: To evaluate and provide a summary of the diagnostic accuracy measures (pooled sensitivity and specificity) of the screening questionnaire employed in the GHiSA GPS. Methods: All studies that adhered to the methodology specified by the GHiSA and provided diagnostic accuracy data were eligible for inclusion. Data on geographical location and diagnostic accuracy parameters (true positive, false positive, true negative and false negative) were extracted from the included studies and entered in duplicate into Microsoft Excel independently by two authors. The quality of the studies was assessed using the quality assessment of diagnostic accuracy studies (QUADAS-2) tool. Results: Data from 25 studies carried out in 23 countries were included in the pooled analysis. The QUADAS-2 assessment revealed a high risk of bias in the domains ‘reference standard’ and ‘patient flow’. For the applicability of the studies, there were concerns about ‘patient selection’. Substantial variations in sensitivity (0.43–1.00) and specificity (0.15–1.00) values were observed globally. A bivariate random effects model showed a pooled sensitivity of 0.88 [95% confidence interval (CI) 0.80–0.94] and a pooled specificity of 0.86 (95% CI 0.78–0.91). The summary receiver operating curve revealed a clustering of studies in the upper left corner, indicating a sensitivity and specificity close to 1. The area under the curve was 0.93, suggesting excellent accuracy. Conclusions: Despite substantial variations in diagnostic estimates around the world, the pooled analysis indicated that the accuracy of the GHiSA screening questionnaire was excellent. The screening questionnaire may prove useful for triage, ensuring that only individuals fitting the criteria for HS see specialized dermatological care.