Prevalence and Patient Characteristics of Ectodermal Dysplasias in Denmark.

Importance: Ectodermal dysplasias constitute a group of rare genetic disorders of the skin and skin appendages with hypodontia, hypotrichosis, and hypohidrosis as cardinal features. There is a lack of population-based research into the epidemiology of ectodermal dysplasias. Objective: To establish a validated population-based cohort of patients with ectodermal dysplasia in Denmark and to assess the disease prevalence and patient characteristics. Design, Setting, and Participants: This nationwide cohort study used individual-level registry data recorded across the Danish universal health care system to identify patients with ectodermal dysplasias from January 1, 1995, to August 25, 2021. A 3-level search of the Danish National Patient Registry and the Danish National Child Odontology Registry was conducted to identify patients with diagnosis codes indicative of ectodermal dysplasias; patients registered in the Danish RAREDIS Database, the Danish Database of Genodermatoses, and local databases were also added. The search results underwent diagnosis validation and review of clinical data using medical records. Of 844 patient records suggestive of ectodermal dysplasias, 791 patients (93.7%) had medical records available for review. Positive predictive values of the diagnosis coding were computed, birth prevalence was estimated, and patient characteristics were identified. Data analysis was performed from May 4 to December 22, 2023. Results: The identified and validated study cohort included 396 patients (median [IQR] age at diagnosis, 13 [4-30] years, 246 females [62.1%]), of whom 319 had confirmed ectodermal dysplasias and 77 were likely cases. The combined positive predictive value (PPV) for ectodermal dysplasia-specific diagnosis codes was 67.0% (95% CI, 62.7%-71.0%). From 1995 to 2011, the estimated minimum birth prevalence per 100 000 live births was 14.5 (95% CI, 12.2-16.7) for all ectodermal dysplasias and 2.8 (95% CI, 1.8-3.8) for X-linked hypohidrotic ectodermal dysplasias. A molecular genetic diagnosis was available for 241 patients (61%), including EDA (n = 100), IKBKG (n = 55), WNT10A (n = 21), TRPS1 (n = 18), EDAR (n = 10), P63 (n = 9), GJB6 (n = 9), PORCN (n = 7), and other rare genetic variants. Conclusions and Relevance: The findings of this nationwide cohort study indicate that the prevalence of ectodermal dysplasias was lower than previously reported. Furthermore, PPVs of the search algorithms emphasized the importance of diagnosis validation. The establishment of a large nationwide cohort of patients with ectodermal dysplasias, including detailed clinical and molecular data, is a unique resource for future research in ectodermal dysplasias.

The Global Hidradenitis Suppurativa Atlas (GHiSA) 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 prevalence rates 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. 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. 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.

Swiss (German) Version of the Actinic Keratosis Quality of Life questionnaire.

BACKGROUND: Actinic keratosis (AK) is a sun-induced skin lesion that may progress to invasive squamous cell carcinoma of the skin. Recently, the Actinic Keratosis Quality of Life questionnaire (AKQoL) was designed for patients with AK in Denmark as a specific quality of life instrument for AK patients. OBJECTIVE: The objective of this study was to adapt the AKQoL for the German language region of Switzerland and to evaluate its psychometric properties (validity, reliability). METHODS: Translation and cultural adaptation of the questionnaire were assessed by using the technique of cognitive interviewing. During the translation process, 34 patients with AK from the Department of Dermatology, University Hospital Zurich, were interviewed in 3 sessions of cognitive interviewing. The translated questionnaire was then distributed together with the Dermatology Life Quality Index (DLQI) to a second group of 113 patients for validation and reliability testing. Within this group, we measured the internal consistency by the Cronbach coefficient α and Spearman correlation coefficient between the AKQoL and the DLQI. RESULTS: The problems encountered during the translation process led to changes in 5 categories as described by Epstein: stylistic changes, change in breadth, change in actual meaning, change in frequency and time frame, change in intensity. We found a Cronbach α of 0.82, an acceptable internal consistency. The Spearman correlation coefficient between total scores of AKQoL and DLQI was 0.57. CONCLUSION: We culturally adapted and validated a Swiss (German) version of the AKQoL questionnaire applicable for the population of a university center in Switzerland to measure and monitor the quality of life in patients with AK.

Disutility in Patients with Hidradenitis Suppurativa: A Cross-sectional Study Using EuroQoL-5D.

Disutility reflects the disability caused by a disease. The EuroQoL-5D (EQ-5D) questionnaire is a measure of health-related overall utility. The questionnaire has only been applied previously to a small number of patients with hidradenitis. In this study a survey of 421 patients with hidradenitis suppurativa was conducted using the EQ-5D questionnaire. Questions regarding pain, malodour and pruritus were included to determine quantitatively whether these factors are associated with low EQ-5D index and visual analogue scale (VAS) scores. The index and VAS scores obtained were compared with reference values for the general population in Denmark. A significantly decreased utility in patients with hidradenitis suppurativa was found for all age group levels, except for 65-74-year-olds. The total index score in the cohort was 0.705 (population mean 0.887) and the VAS was 62.25 (population mean 82.6). Multivariate analysis found significant associations between loss of utility and pain, malodour and pruritus (p < 0.0001). Patients with hidradenitis suppurativa had a significantly decreased EQ-5D compared with the background population. Malodour and pruritus were found to be associated with low index values, and pain and malodour with low VAS. Patient-reported pain and discomfort had the most negative overall effect on mean index scores.

A systematic literature review to compare quality of life in psoriasis with other chronic diseases using EQ-5D-derived utility values.

BACKGROUND: Psoriasis is a chronic, immune-mediated dermatological disease associated with substantial economic, clinical, and humanistic burden. OBJECTIVE: The aim of this study was to understand the disutility of patients with psoriasis vulgaris, using mean baseline EuroQoL five dimensions (EQ-5D) index scores reported in the published literature, and to compare this to patients with other chronic diseases. METHODS: Two systematic literature searches were conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Searches were conducted in ten databases including Embase, MEDLINE, and the Cochrane Central Register of Controlled Trials (CENTRAL). The first search (December 2013) used search terms psoria* AND (EQ5D OR EQ OR EUROQoL). Only publications of original research, which reported baseline EQ-5D scores for mild/moderate/severe psoriasis, were included. The second search (March 2014) used the terms (systematic review) AND (EQ5D OR EQ 5D OR EuroQoL). Titles were screened by two independent reviewers. Four independent reviewers reviewed titles and full-length papers. EQ-5D scores for psoriasis patients were qualitatively compared with scores from patients with other chronic diseases identified through the literature search. RESULTS: Of 133 publications on psoriasis, 12 met the inclusion criteria. The mean EQ-5D index scores for psoriasis (all severities) ranged from 0.52 (standard deviation: 0.39) to 0.9 (standard deviation: 0.1). Of the 48 results from the second search, six met the inclusion criteria. The reported EQ-5D lower limit for other diseases ranged from 0.20 (Type 2 diabetes mellitus) to 0.66 (liver diseases). The highest EQ-5D estimates for other diseases ranged from 0.79 (liver diseases) to 0.93 (cancer patients). Both lower and upper EQ-5D estimates in psoriasis patients were within the range of those reported for other chronic diseases. CONCLUSION: Comparative studies of morbidity are relevant in health care studies and patient advocacy. This systematic review demonstrates that the ranges of disutility among psoriasis patients are within the ranges of other chronic diseases (cardiovascular diseases, diabetes, end-stage renal diseases, liver diseases, cancer, and visual disorders).

Interpretation of the skin cancer quality of life score: a validated quality of life questionnaire for non-melanoma skin cancer.

BACKGROUND: Health-related quality of life (HRQoL) instruments are used increasingly. In order to assign clinical meaning to HRQoL scores, the interpretation of instruments is essential but lagging in dermatology. OBJECTIVE: To establish a clinical interpretation of the Skin Cancer Quality of Life questionnaire (SCQoL), a newly validated HRQoL instrument for patients with non-melanoma skin cancer (NMSC), using an anchor-based method, and to test the responsiveness. METHODS: Receiver-operating characteristic analysis was used to propose clinically meaningful cut-off scores for SCQoL including 101 patients with NMSC. RESULTS: The following bands were established: score 0-3 corresponds to no impairment, 4-6 corresponds to mild impairment, 7-10 to moderate impairment and 11-27 to severe impairment of HRQoL. Testing the responsiveness shows a moderate effect size and significantly lower scores only for the domain emotion and the global item. CONCLUSION: Using proposed clinical cut-off scores for SCQoL may help clinicians in their decision-making, help monitoring clinical improvement and classify patients just as e.g. the Dermatology Life Quality Index can.