Cost-Effectiveness of Dupilumab and Oral Janus Kinase Inhibitors for the Treatment of Moderate-to-Severe Atopic Dermatitis in Singapore.

BACKGROUND: Atopic dermatitis (AD) affects both adults and children, impacting their quality of life and productivity; however, traditional systemic treatments such as cyclosporine have limitations. Emerging novel systemic interventions, including monoclonal antibodies and Janus kinase (JAK) inhibitors, have been shown to improve patient outcomes. OBJECTIVE: This study evaluates the cost-effectiveness of novel systemic interventions for moderate-to-severe AD in adults compared with the best supportive care (BSC) in Singapore. METHODS: The economic evaluation used a hybrid model consisting of a decision tree and Markov model. Treatment responses at 16 weeks were based on a network meta-analysis that was developed specifically for this study. Long-term response, discontinuation rates, episodes of flares and treatment-emergent adverse events were obtained from key dupilumab, abrocitinib, baricitinib and upadacitinib trials. The study had a 5-year time horizon and considered the healthcare payer's perspective. Sensitivity and scenario analyses were performed as well. RESULTS: Baricitinib 4 mg and 2 mg have the lowest incremental cost-effectiveness ratios, at Singapore dollars (S$) 60,730/quality-adjusted life-year (QALY) and S$66,842/QALY, respectively. Upadacitinib 30 mg offers the highest incremental QALY gain, while baricitinib 2 mg offers the least. The cost of the intervention drugs accounted for the highest proportion of the overall expenses (68-93%) for those in the maintenance state. Other influential factors within the model included (1) the incremental utility derived from intervention response; (2) the probability of achieving Eczema Area and Severity Index 75 (EASI-75) with BSC; and (3) the relative risk of achieving EASI-75 with the interventions. In a scenario where the cost of all drugs is matched to the lowest-priced drug, the top three cost-effectiveness interventions are dupilumab, upadacitinib 30 mg and abrocitinib 200 mg, respectively. CONCLUSION: The interventions are found to be cost-effective at their existing prices when compared with BSC. Ideally, a composite score of treatment success and quality-of-life scores ought to be included, but such data were unavailable. Future research should consider conditional discontinuation data and long-term outcomes when such data become accessible.

Bridging the Gap: Comparing Patient-Clinician Views on Treatment Goals and Communication in the Management of Atopic Dermatitis Within the Asia-Pacific Region.

INTRODUCTION: It remains unclear how patients with atopic dermatitis (AD) and clinicians perceive the level of patient-clinician communication and if there could be potential lapses. This cross-sectional study aims to compare perspectives between patients with AD and dermatologists regarding communication and treatment expectations in Asia. METHODS: Moderate-to-severe patients with AD and practicing dermatologists were recruited from eight Asia-Pacific territories, including Mainland China, Hong Kong, India, Japan, Singapore, South Korea, Taiwan, and Thailand. Patients and dermatologists completed separate surveys designed to elicit their expectations regarding AD management, and their perceived level of patient-clinician communication. Patients were also asked about their treatment satisfaction and whether they prefer additional treatment beyond what was prescribed. Demographic information and responses were analyzed using descriptive statistics. The study was reviewed by the institutional review board in each territory, and all participants provided informed consent. RESULTS: A total of 1103 patients and 271 dermatologists completed the surveys. Both patients and dermatologists were largely aligned in their top treatment goals in AD management. However, greater proportions of patients prioritized the prevention of exacerbation (78.0% versus 47.2%), minimization of treatment adverse effects (46.4% versus 9.1%), and improvement in mental health (16.0% versus 4.9%), compared with dermatologists. Although patient-clinician communication was observed to be generally good, 10.9% of patients reported dissatisfaction with communication in AD management. The majority of patients were either "very satisfied" or "satisfied" with their latest acute AD treatment, but 65.5% of patients still desired additional treatment. CONCLUSIONS: This multinational study has provided insights on the perspectives of Asian patients and dermatologists in treatment goals, AD management, and communication. In general, both patients and dermatologists were aligned in treatment goals and there was satisfactory patient-clinician communication in most aspects. However, potential areas of improvement have been identified to further enhance patient-centered care.

Standardized Protocols for Clinical and Histopathological Characterization of Hidradenitis Suppurativa Tissue Specimens.

Methods for describing and reporting the clinical and histologic characteristics of cutaneous tissue samples from patients with hidradenitis suppurativa (HS) are not currently standardized, limiting clinicians' and scientists' ability to uniformly record, report, and communicate about the characteristics of tissue used in translational experiments. A recently published consensus statement outlined morphological definitions of typical HS lesions, but no consensus has been reached regarding clinical characterization and examination of HS tissue samples. In this study, we aimed to establish a protocol for reporting histopathologic and clinical characteristics of HS tissue specimens. This study was conducted from May 2023 to August 2023. Experts in clinical care, dermatopathology, and translational research were recruited, and a modified Delphi technique was used to develop a protocol for histologic reporting and clinical characterization of submitted tissue specimens from patients with HS. A total of 27 experts participated (14 dermatologists, 3 fellowship-trained dermatopathologists, 3 plastic surgeons, 3 general surgeons, and 4 research scientists) in creating and reviewing protocols for the clinical and histopathological examination of HS tissue specimens. The protocols were formatted as a synoptic report and will help to consistently classify specimens in biobanks on the basis of histologic features and more accurately report and select samples used in translational research projects.

Nail changes in pemphigus: a systematic review and meta-analysis.

Pemphigus is a group of autoimmune mucocutaneous bullous disorders characterized by acantholysis resulting from autoantibodies targeting epithelial cell surface antigens. Studies reflect the presence of nail manifestations in some patients and suggest a potential correlation with clinical severity. This study examines the overall prevalence and characterizes the diverse manifestations of nail changes in pemphigus. We searched Cochrane, MEDLINE, EMBASE, and LILACS from 1990 to June 26, 2023 for studies reporting different nail changes in pemphigus patients. Data were collected and pooled to obtain proportions of the prevalence of nail changes in patients with pemphigus and subgroup analysis for pemphigus foliaceous and pemphigus vulgaris. The risk of bias was assessed with the Joanna Briggs Institute Checklist. Of 321 studies screened, 14 studies with 1,208 patients were included. Paronychia (n = 185) and Beau's lines (n = 104) were the most common nail changes identified. The pooled prevalence of nail disease in pemphigus patients was 0.389 (number of studies; [95% CI]: n = 9; [0.160-0.680], with high heterogeneity between studies (I2 = 95.0%, P < 0.001). Subgroup analysis revealed the highest prevalence in pemphigus foliaceous at 0.342 (n = 3; [0.109-0.688]) and pemphigus vulgaris at 0.396 (n = 5; [0.114-0.769]). Nail changes exhibited varied temporal relationships with disease onset and flares, preceding, concurrent, or following these events. Correlation with disease severity was noted, although discrepancies between studies were reported. Nail changes in pemphigus, particularly pemphigus vulgaris and pemphigus foliaceous, may be underrecognized. Observations regarding temporal associations and potential correlations with disease severity highlight the diagnostic and prognostic implications of nail changes in pemphigus. The limitations of this study include study heterogeneity and possible bias. Further research to establish the correlation of the presence and severity of nail changes on the overall disease course would be helpful.

Response to adalimumab in Caucasian and Asian patients with hidradenitis suppurativa: A retrospective cohort study of an Australian cohort stratified by patient-reported ethnicity.

BACKGROUND/OBJECTIVES: Caucasian and Asian patients with hidradenitis suppurativa demonstrate significant differences with regard to age, gender and body mass index. Demographic characteristics are known to influence the efficacy and drug survival of hidradenitis suppurativa therapeutics including biologic therapies. What remains unknown is the impact of ethnicity upon the efficacy of therapeutics once demographic and disease characteristics have been taken into account. This is an important question given the expansion of biologic therapies for HS into the global patient community. METHODS: We assessed 170 patients from a single HS specialist centre in Australia stratified by patient-identified ethnicity including those identifying as either Caucasian or Asian. RESULTS: Asian patients demonstrated lower BMI, higher rates of smoking and greater odds of Hurley stage 3 disease with tunnels than Caucasian patients in line with the reported literature. There was no significant difference between percentage of individuals achieving HiSCR50 or IHS4-55 at Week 16. Significant differences were seen in median time to secondary loss of response, and Kaplan-Meier curve analysis showed a significant difference between curves when stratified by patient-reported ethnicity. Cox regression analysis demonstrated after accounting for age, gender, BMI, smoking and Hurley stage, the significance of ethnicity in influencing time to secondary loss of response disappears. CONCLUSIONS: Caucasian or Asian ethnicity does not influence response to adalimumab treatment on patients with hidradenitis suppurativa.

Development and validation of the Dermatology Social Comparison (DSC) Scale.

BACKGROUND: Social comparison, the process of evaluating one's characteristics in relation to others, influences individuals' self-perception and behavior. However, instruments are scarce for assessing social comparison in the medical setting. OBJECTIVES: Our aim was to develop and validate a new scale for assessing social comparison. MATERIALS AND METHODS: Seven statements were developed, encompassing the perceived normality of having rashes, the tendency to compare their situation with others, and the emotional response when seeing someone better or worse off than themselves. The instrument was piloted in 15 patients for readability and face validity, then prospectively validated using modern psychometric methods in 1,053 adult patients with eczema or psoriasis from three tertiary dermatological centers in Singapore. RESULTS: Of 1,053 adult patients, 802 (76.2%) had eczema, and 251 (23.8%) had psoriasis. Exploratory factor analysis (using a 70% sample split) showed a single factor model comprising three questions (Eigenvalue: 1.4). Confirmatory factor analysis with the remaining 30% of the sample confirmed an excellent model fit. Cronbach's alpha was 0.7, and inter-item correlations ranged from 0.42 to 0.46. In the Rasch analysis, item fit statistics and item characteristic curves showed appropriate discrimination between response options, although reliability was suboptimal with a person separation reliability of 0.63. CONCLUSIONS: Comprising 3 questions, the newly derived social comparison scale showed acceptable psychometrics as a measure of social comparison for clinical and research purposes in dermatology. Its brief nature likely results from its brevity and applicability to conditions beyond eczema and psoriasis, which warrants further investigation.

The Global Hidradenitis Suppurativa Atlas Methodology: Combining Global Proportions in a Pooled Analysis.

INTRODUCTION: Data concerning the global burden of hidradenitis suppurativa (HS) are limited. Reported prevalence estimates vary between 0.0003% and 4.1%, and data from various geographical regions are still to be collected. Previously reported prevalences have been limited by the methodological approach and source of data. This has resulted in great heterogeneity as prevalence data from physician-diagnosed cases poorly match those of self-reported apparent HS disease. METHODS: The Global Hidradenitis Suppurativa Atlas (GHiSA) introduces an innovative approach to determine the global prevalence of HS. This approach involves using a previously validated questionnaire to screen apparently healthy adults accompanying a patient to a non-dermatological outpatient clinic visit in a hospital or a private/family medicine clinic. The screening questionnaire (i.e., the index test) is combined with a subsequent physician-based in-person validation (i.e., the reference standard) of the participants who screen positive. Approximately ten percent of the screen-negative participants are also clinically assessed to verify the diagnostic precision of the test. The local prevalence (pi) will be estimated from each country that submits the number of patients who are HS positive according to the index test and clinical examination (n), and the corresponding total number of observations (N). CONCLUSION: The GHiSA Global Prevalence studies are currently running simultaneously in 58 countries across six continents (Africa, Europe, Australia, North America, South America, and Asia). The goal of the combined global proportion is the generation of a single summary (i.e., proportional meta-analysis), which will be done after a logit transformation and synthesized using a random-effects model. The novel standardization of the Global Prevalence Studies conducted through GHiSA enables direct international comparisons, which were previously not possible due to substantial heterogeneity in past HS prevalence studies.

S2k guidelines on diagnosis and treatment of linear IgA dermatosis initiated by the European Academy of Dermatology and Venereology.

INTRODUCTION: Linear IgA dermatosis (LAD) is a rare subepidermal autoimmune bullous disease (AIBD) defined by predominant or exclusive immune deposits of immunoglobulin A at the basement membrane zone of skin or mucous membranes. This disorder is a rare, clinically and immunologically heterogeneous disease occurring both in children and in adults. The aim of this project is to present the main clinical features of LAD, to propose a diagnostic algorithm and provide management guidelines based primarily on experts' opinion because of the lack of large methodologically sound clinical studies. METHODS: These guidelines were initiated by the European Academy of Dermatology and Venereology (EADV) Task Force Autoimmune Bullous Diseases (AIBD). To achieve a broad consensus for these S2k consensus-based guidelines, a total of 29 experts from different countries, both European and non-European, including dermatologists, paediatric dermatologists and paediatricians were invited. All members of the guidelines committee agreed to develop consensus-based (S2k) guidelines. Prior to a first virtual consensus meeting, each of the invited authors elaborated a section of the present guidelines focusing on a selected topic, based on the relevant literature. All drafts were circulated among members of the writing group, and recommendations were discussed and voted during two hybrid consensus meetings. RESULTS: The guidelines summarizes evidence-based and expert opinion-based recommendations (S2 level) on the diagnosis and treatment of LAD. CONCLUSION: These guidelines will support dermatologists to improve their knowledge on the diagnosis and management of LAD.

Global consensus process to establish a core dataset for hidradenitis suppurativa registries.

BACKGROUND: Several registries for hidradenitis suppurativa (HS) already exist in Europe and the USA. There is currently no global consensus on a core dataset (CDS) for these registries. Creating a global HS registry is challenging, owing to logistical and regulatory constraints, which could limit opportunities for global collaboration as a result of differences in the dataset collected. The solution is to encourage all HS registries to collect the same CDS of information, allowing registries to collaborate. OBJECTIVES: To establish a core set of items to be collected by all HS registries globally. The core set will cover demographic details, comorbidities, clinical examination findings, patient-reported outcome measures and treatments. METHODS: Beginning in September 2022, 20 participants - including both clinicians with expertise in HS and patient advocates - from eight countries across three continents participated in a Delphi process consisting of four rounds of voting, with all participants completing each round. A list of potential items for inclusion in the core set was generated from the relevant published literature, including systematic reviews of comorbidities in HS, clinical and examination findings, and epidemiology. For disease severity and progression items, the Hidradenitis SuppuraTiva Core outcome set International Collaboration (HiSTORIC) core set and other relevant instruments were considered for inclusion. This resulted in 47 initial items. Participants were invited to suggest additional items to include during the first round. Anonymous feedback was provided to inform each subsequent round of voting to encourage consensus. RESULTS: The eDelphi process established a CDS of 48 items recommended for inclusion in all HS registries globally. CONCLUSIONS: The routine adoption of this CDS in current and future HS registries should allow registries in different parts of the world to collaborate, enabling research requiring large numbers of participants.

Infectious Disease Screening Prior to Systemic Immunomodulatory Therapy in Hidradenitis Suppurativa: Consensus Guidelines from the Asia-Pacific Hidradenitis Suppurativa Foundation.

BACKGROUND: Current infectious disease screening recommendations for hidradenitis suppurativa (HS) are adopted from recommendations in chronic plaque psoriasis. No HS-specific guidelines for infectious disease screening prior to immunomodulatory therapy have been developed. OBJECTIVES: To establish an expert Delphi consensus of recommendations regarding infectious disease screening prior to systemic immunomodulatory therapy in HS. METHODS: Participants were identified via recent publications in the field and were sent a questionnaire regarding infectious diseases encountered in the setting of HS, and opinions regarding infectious disease screening prior to various systemic immunomodulatory therapies. All questions were informed by a systematic literature review regarding infections exacerbated or precipitated by immunomodulatory therapy. Questionnaire responses were followed by round-table discussion with a core group of 8 experts followed by a final round of questionnaires resulting in achievement of consensus. RESULTS: 44 expert HS physicians from 12 countries on 5 continents participated in the development of the expert consensus recommendations. Consensus recommendations include screening for hepatitis B, hepatitis C and tuberculosis in all individuals with HS prior to therapy. All immunomodulatory therapies (biologic and systemic immunosuppressant therapy) should be preceded by infectious disease screening including patient and location specific considerations for endemic local diseases and high-risk activities and occupations. Clinical assessment has a significant role in determining the need for laboratory screening in the setting of many uncommon or tropical diseases such as leprosy, leishmaniasis and strongyloidiasis. CONCLUSIONS: The presented consensus recommendations are the first specifically developed for pre-treatment infectious disease screening in Hidradenitis Suppurativa.

Teledermatology in an emergency department: benefits and gaps.

BACKGROUND: Teledermatology has provided new avenues through which dermatologists can provide healthcare. Teledermatology was introduced to the Emergency Department (ED) to enable immediate dermatological consult. We aimed to assess the impact of teledermatology on the management of dermatological conditions by emergency medicine physicians and subsequent health resource utilization. METHODS: We conducted a retrospective review of teledermatology referrals from the ED of our tertiary hospital in Singapore from June 2015 to December 2019. The dermatological conditions, the triaging and treatment recommendations were analyzed. Follow-up plans were recorded. RESULTS: Between June 2015 and December 2019, 147 patients were referred from the ED via teledermatology; 11 (7.5%) were admitted, and 136 (92.5%) were recommended to be discharged with a dermatological diagnosis and management plan. If required, a follow-up appointment in the dermatology specialist clinic was arranged. Of the 136 patients who were discharged, 129 (94.9%) patients were provided with outpatient appointment in the dermatology clinic, out of which 110 patients returned for follow-up. 90 (81.8%) patients retained the initial teledermatology diagnoses and 20 (18.2%) patients had their teledermatology diagnoses revised after in-person review. CONCLUSIONS: Teledermatology allows for more efficient triaging of patients with dermatological conditions. Reliability between teledermatology and clinic-based examination is good. Patients may be managed mainly in the outpatient setting with appropriate specialty-directed treatment, return advice, and appropriately-triaged follow-up outpatient appointment.

Dermatologists' Perceptions of the Use of Teledermatology in Managing Hidradenitis Suppurativa: Survey Study.

BACKGROUND: The field of teledermatology has expanded tremendously and has been used for conditions including hidradenitis suppurativa (HS). However, due to the sensitive location of lesions, HS may be considered less suitable for teledermatology. OBJECTIVE: We sought to assess dermatologists' experiences and perceptions toward using teledermatology for HS relative to atopic dermatitis (AD) as a comparison. METHODS: A survey was disseminated electronically to practicing dermatologists in the Asia-Pacific region between February and June 2022. Differences in attitudes and perceptions between HS and AD were compared using random-effects ordered logistic regression, controlling for demographics. RESULTS: A total of 100 responses were obtained comprising of 76 (81.7%) dermatologists and 17 (18.3%) dermatology trainees; 62.6% (62/98) of physicians were uncomfortable with using teledermatology for HS. Multivariable regression confirmed increased perceived challenges with managing HS using teledermatology compared to AD. These challenges include the need for photography of hard-to-reach or sensitive areas (odds ratio [OR] 4.71, 95% CI 2.44-9.07; P<.001), difficulties in accurate assessment of severity (OR 2.66, 95%CI 1.48-4.79; P=.001), and inability to palpate lesions (OR 2.27, 95% CI 1.23-4.18; P=.009). CONCLUSIONS: This study confirms the relative reluctance of dermatologists to use teledermatology for HS and complements existing data showing mixed levels of willingness from patients. The use of teledermatology for HS may need to be optimized to overcome these challenges, including increasing security features, selection of patients with milder or limited diseases, and selecting patients with an established and strong doctor-patient relationship.

Understanding Discordant Perceptions of Disease Severity Between Physicians and Patients With Eczema and Psoriasis Using Structural Equation Modeling.

Importance: Patients and physicians often have differing opinions on the patient's disease severity. This phenomenon, termed discordant severity grading (DSG), hinders the patient-physician relationship and is a source of frustration. Objective: To test and validate a model explaining the cognitive, behavioral, and disease factors associated with DSG. Design, Setting, and Participants: A qualitative study was first performed to derive a theoretical model. In this subsequent prospective cross-sectional quantitative study, the qualitatively derived theoretical model was validated using structural equation modeling (SEM). Recruitment was conducted between October 2021 and September 2022. This was a multicenter study in 3 Singapore outpatient tertiary dermatological centers. Dermatology patients and their attending physicians were recruited by convenience sampling. Patients were aged 18 to 99 years with psoriasis or eczema of at least 3 months' duration and recruited only once. The data were analyzed between October 2022 to May 2023. Main Outcomes and Measures: The outcome was the difference between global disease severity (0-10 numerical rating scale with a higher score indicating greater severity) as independently scored by the patient and the dermatologist. Positive discordance was defined as patient-graded severity more than 2 points higher (graded more severely) than physicians, and negative discordance if more than 2 points lower than physicians. Confirmatory factor analysis followed by SEM was used to assess the associations between preidentified patient, physician, and disease factors with the difference in severity grading. Results: Of the 1053 patients (mean [SD] age, 43.5 [17.5] years), a total of 579 (55.0%) patients were male, 802 (76.2%) had eczema, and 251 (23.8%) had psoriasis. Of 44 physicians recruited, 20 (45.5%) were male, 24 (54.5%) were aged between 31 and 40 years, 20 were senior residents or fellows, and 14 were consultants or attending physicians. The median (IQR) number of patients recruited per physician was 5 (2-18) patients. Of 1053 patient-physician pairs, 487 pairs (46.3%) demonstrated discordance (positive, 447 [42.4%]; negative, 40 [3.8%]). Agreement between patient and physician rating was poor (intraclass correlation, 0.27). The SEM analyses showed that positive discordance was associated with higher symptom expression (standardized coefficient B = 0.12; P = .02) and greater quality-of-life impairment (B = 0.31; P < .001), but not patient or physician demographics. A higher quality-of-life impairment was in turn associated with lower resilience and stability (B = -0.23; P < .001), increased negative social comparisons (B = 0.45; P < .001), lower self-efficacy (B = -0.11; P = .02), increased disease cyclicity (B = 0.47; P < .001), and greater expectation of chronicity (B = 0.18; P < .001). The model was well-fitted (Tucker-Lewis: 0.94; Root Mean Square Error of Approximation: 0.034). Conclusions and Relevance: This cross-sectional study identified various modifiable contributory factors to DSG, increased understanding of the phenomenon, and set a framework for targeted interventions to bridge this discordance.

Hashimoto Thyroiditis beyond Cytology: A Correlation between Cytological, Hormonal, Serological, and Radiological Findings.

Introduction: Hashimoto thyroiditis is the most common cause of chronic inflammation of the thyroid gland. Ultrasound is the modality for detection, while fine needle aspiration is the gold standard method for diagnosis. Serologic markers, such as antithyroidal peroxidase antibody (TPO) and antithyroglobulin antibody (TG), are usually elevated. Aim: The main objective is to appraise the incidence of neoplasms on a background of Hashimoto thyroiditis. Our second objective is to recognize the different sonographic appearances of Hashimoto thyroiditis, to focus on its nodular and focal patterns, and to measure the sensitivity of the ACR TIRAD system (2017) when interpreted on patients with Hashimoto thyroiditis. Methods: A single-center retrospective cross-sectional study. We studied 137 cases diagnosed cytologically as Hashimoto thyroiditis from January 2013-December 2019. The data collected were analyzed using SPSS (26th edition), and ultrasounds were reviewed by a single board-certified radiologist. The ACR thyroid imaging and Data System 2017 (ACR TI-RADs 2017) and the Bethesda System for reporting thyroid cytology 2017 (BSRTC 2017) were used for reporting ultrasound and cytology, respectively. Results: The mean age was 44.66 years and the female : male was 9 : 1. Serologically, anti-Tg was high in 22 cases (38%), while anti-TPO was positive in all of the 60 cases studied. Histologically, 11 cases were diagnosed with papillary thyroid carcinoma (8%) and a single case with follicular adenoma (0.7%). Ultrasonographically, 50% of the cases showed diffuse pattern, in which 13% of them showed micronodules. 32.2% were macronodular, and 17.7% were a focal nodular pattern. 45 nodules were interpreted with the ACR TIRAD system (2017), in which 22.2% were TR2, 26.6% were TR3, 17.7% were TR4, and 33.3% were TR5. Conclusion: Hashimoto thyroiditis is a risk factor for developing thyroid neoplasms, which necessitate a proper assessment of the cytological material studied and a correlation with the clinical and radiological features. Recognizing the different types of Hashimoto thyroiditis and its variable appearances is significantly important in performing and interpreting thyroid ultrasound imaging. Microcalcification is the most sensitive parameter to discriminate between PTC and nodular type of Hashimoto thyroiditis. The TIRAD system (2017) is a useful tool for risk stratification; however, it might create unnecessary FNA studies in the setting of Hashimoto thyroiditis because of its variable appearances on ultrasound. A modified TIRAD system for patients with Hashimoto thyroiditis is important to alleviate this confusion. Finally, anti-TPO is a sensitive marker for detecting Hashimoto thyroiditis, which could be used for future referencing of newly diagnosed cases.

Knowledge, attitudes, and perceptions of hidradenitis suppurativa among young adults in Singapore.

Background: The prevalence of hidradenitis suppurativa (HS) is 0.00033% to 4.10% globally. Few epidemiological studies derive from Asia, with social stigmatization postulated to result in under-diagnosis. Objective: This study aimed to assess the self-reported prevalence of HS, and the knowledge, attitudes, and perceptions towards HS among Singaporean young-adults. Methods: A cross-sectional study (n = 158) was conducted by anonymous online questionnaire. The association between demographic factors and risk of potentially undiagnosed HS was evaluated using multivariable logistic regression. Differences between attitude-perception scores by demographic factors and knowledge of HS were tested using two-sample t-tests. Results: The prevalence of diagnosed and potentially undiagnosed HS was 0.63% and 8.9%, respectively. Non-Chinese had significantly higher social attitude-perception scores than Chinese (P = .029). Females had significantly higher social (P = .048) as well as economic and work (P = .037) attitude-perception scores than males. Those with knowledge of HS had significantly higher attitude-perception scores for interpersonal (P = .031) and social (P = .0052) subsections. Limitations: Small sample size, low frequency of HS cases, and self-reported prevalence may not generalize to the broader population in Singapore. Conclusion: Our results suggest a potential underdiagnosis of HS. Non-Chinese stigmatize HS less than Chinese, and females less than males. Individuals with knowledge of HS might be more open to interpersonal and social interactions with HS sufferers.