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.

Clinical presentation and genetics of tricho-rhino-phalangeal syndrome (TRPS) type 1: A single-center case series of 15 patients and seven novel TRPS1 variants

Tricho-rhino-phalangeal syndrome (TRPS) is a rare malformation syndrome characterized by distinctive facial, ectodermal, and skeletal features. TRPS is divided into TRPS type I/III caused by pathogenic variants in TRPS1 and TRPS type II caused by contiguous gene deletions also spanning EXT1 and RAD21. Due to its rarity, knowledge of the clinical course of TRPS remains limited. Therefore, we collected and characterized a case series of 15 TRPS type I patients (median age at diagnosis 15 [interquartile range: 10-18] years, 11 females [73%]) seen at Aarhus University Hospital, Denmark, with a median follow-up period of 10 years. We estimated a minimum point prevalence of 0.5 in 100,000 (95% CI: 0.3-0.8 per 100,000) persons. Common craniofacial features included fine and sparse hair with a high anterior hairline, eyebrows with lateral thinning and a thicker medial part, prominent ears, a bulbous nose tip with small nasal alae, a low-hanging, and often wide columella, and a long philtrum with a thin upper vermillion. Specific skeletal features included short stature and deviating and short fingers with cone-shaped epiphyses and shortened metacarpals on radiographs. The most significant morbidity of the cohort was joint complaints, which were reported by all patients, often already before the TRPS diagnosis was established. We identified ten different TRPS1 variants including both frameshift/nonsense, missense, and splice-site variants, including seven variants not previously reported in the literature. In accordance with previous literature, no genotype-phenotype correlation was identified. The clinical trajectories were heterogeneous involving pediatrics, dermatology, orthopedic surgery, clinical genetics, and/or odontology, emphasizing that close multidisciplinary collaboration is essential for early diagnosis of TRPS and to ensure proper and timely patient care and counseling.

Autoimmune blistering disorders and cardiovascular risks: A population-based cohort study

BACKGROUND

Autoimmune blistering disorders (ABDs) might elevate cardiovascular risk, but studies are lacking.

OBJECTIVE

The objective of this study was to examine if ABDs elevate the risk of atherosclerotic cardiovascular disease, heart failure, arrhythmia, venous thromboembolism, and cardiovascular death.

METHODS

A population-based cohort of Danish patients with ABD (≥18 years of age) diagnosed during 1996-2021 (n = 3322) was compared with an age- and sex-matched comparison cohort from the general population (n = 33,195).

RESULTS

Compared with the general population, patients with ABDs had higher 1-year risks of atherosclerotic cardiovascular disease (3.4% vs 1.6%), heart failure (1.9% vs 0.7%), arrhythmia (3.8% vs 1.3%), venous thromboembolism (1.9% vs 0.3%), and cardiovascular death (3.3% vs 0.9%). The elevated risk persisted after 10 years for all outcomes but arrhythmia. The hazard ratios associating ABDs with the outcomes during the entire follow-up were 1.24 (1.09-1.40) for atherosclerotic cardiovascular disease, 1.48 (1.24-1.77) for heart failure, 1.16 (1.02-1.32) for arrhythmia, 1.87 (1.50-2.34) for venous thromboembolism, and 2.01 (1.76-2.29) for cardiovascular death. The elevated cardiovascular risk was observed for both pemphigus and pemphigoid.

LIMITATIONS

Our findings might only generalize to patients with ABDs without prevalent cardiovascular diseases.

CONCLUSION

Patients with ABDs had an elevated cardiovascular risk compared with age- and sex-matched controls.

Prevalence of skin sensitization and dermatitis among epoxy-exposed workers in the wind turbine industry

BACKGROUND

A high prevalence of skin sensitization and dermatitis has been reported among workers exposed to epoxy components.

OBJECTIVES

To estimate the risk of skin sensitization and dermatitis among workers exposed to epoxy components during production of wind turbine blades while using comprehensive safety measures.

METHODS

A cross-sectional study of 180 highly epoxy-exposed production workers and 41 nonexposed office workers was conducted at two wind turbine blade factories in Denmark. Participants underwent a skin examination, were tested with a tailored patch test panel including epoxy-containing products used at the factories, and answered a questionnaire.

RESULTS

Sixteen production workers (8·9%) were sensitized to an epoxy component compared with none of the office workers. Skin sensitization was more frequent within the first year of exposed employment. Strong selection bias by atopic status was indicated. Among nonatopic workers, the prevalence of dermatitis was higher among production workers (16·4%) than among office workers [6·5%, odds ratio (OR) 2·3, 95% confidence interval (CI) 0·6-9·1] and higher among the sensitized workers (43·8%) than the nonsensitized workers (14·6%, OR 4·5, 95% CI 1·6-12·7). Resins based on diglycidyl ether of bisphenol A and F were the most frequent sensitizers. One of the four workers sensitized to epoxy components used at the factories did not react to the epoxy resin of the TRUE test^® panel.

CONCLUSIONS

Despite comprehensive skin protection, sensitization and dermatitis are prevalent among highly epoxy-exposed workers in the wind turbine industry in Denmark. Our findings document the need for intensified preventive efforts and emphasize the importance of tailored patch testing. What is already known about this topic? Epoxy components are well-known sensitizers of the skin. A high prevalence of skin sensitization and dermatitis has been reported among workers exposed to epoxy components. Comprehensive protective equipment is recommended when working with epoxy components. What does this study add? Despite comprehensive skin protection, skin sensitization and dermatitis are prevalent among epoxy-exposed workers. We found that 40% of workers sensitized to epoxy products had dermatitis. Only 75% of the sensitized workers were detected by the epoxy resin of the TRUE test^® , which emphasizes the importance of tailored testing.

Perceived psychological stress and risk of herpes zoster: a nationwide population-based cohort study

BACKGROUND

Psychological stress may reduce cellular immunity, but its role in triggering latent infections, including herpes zoster (HZ), is controversial.

OBJECTIVES

To examine the association between perceived psychological stress and risk of HZ.

METHODS

In a linked registry-based cohort study, we followed 77 310 persons aged 40 years or older who participated in the 2010 Danish National Health Survey from 1 May 2010 until HZ diagnosis, death, emigration or 1 July 2014, whichever occurred first. We computed hazard ratios (HRs) of HZ associated with Cohen's Perceived Stress Scale (PSS) score (range 0-40) using Cox regression with age as the timescale, adjusted for sex, immunosuppressive and selected chronic conditions, immunosuppressive drugs, and sociodemographic, lifestyle and anthropometric factors. The PSS measures chronic stress perceived by an individual in response to various demands of daily life. We modelled the PSS score using quintiles and a restricted cubic spline function.

RESULTS

The unadjusted rate of HZ varied from 5·53 to 7·20 per 1000 person-years from the lowest to the highest PSS score quintile. Compared with the lowest PSS score quintile, the adjusted HR for HZ was 1·00 [95% confidence interval (CI) 0·86-1·16], 1·08 (95% CI 0·92-1·26), 1·05 (95% CI 0·90-1·23) and 1·14 (95% CI 0·97-1·34) for the second to the fifth quintile, respectively. In cubic spline analyses, PSS scores < 20 were not associated with increased HR of HZ, but thereafter the HR increased linearly from 1·10 (95% CI 0·85-1·41) to 2·22 (95% CI 1·32-3·75).

CONCLUSIONS

Our study indicated that high levels of psychological stress are associated with increased risk of HZ.

Associations of Lifestyle and Anthropometric Factors With the Risk of Herpes Zoster: A Nationwide Population-Based Cohort Study

The role of lifestyle in development of herpes zoster remains unclear. We examined whether smoking status, alcohol consumption, body mass index, or physical activity were associated with zoster risk. We followed a population-based cohort of 101,894 respondents to the 2010 Danish National Health Survey (baseline, May 1, 2010) until zoster diagnosis, death, emigration, or July 1, 2014, whichever occurred first. We computed hazard ratios for zoster associated with each exposure, using Cox regression with age as the time scale and adjusting for potential confounders. Compared with never smokers, hazards for zoster were increased in former smokers (1.17, 95% confidence interval (CI): 1.06, 1.30), but not in current smokers (1.00, 95% CI: 0.89, 1.13). Compared with low-risk alcohol consumption, neither intermediate-risk (0.95, 95% CI: 0.84, 1.07) nor high-risk alcohol consumption (0.99, 95% CI: 0.85, 1.15) was associated with zoster. We also found no increased hazard associated with weekly binge drinking versus not (0.93, 95% CI: 0.77, 1.11). Risk of zoster varied little by body mass index (referent = normal weight) and physical activity levels (referent = light level), with hazard ratios between 0.96 and 1.08. We observed no dose-response association between the exposures and zoster. The examined lifestyle and anthropometric factors thus were not risk factors for zoster.

Atopic dermatitis and risk of atrial fibrillation or flutter: A 35-year follow-up study

BACKGROUND

Atopic dermatitis is characterized by chronic inflammation, which is a risk factor for atrial fibrillation.

OBJECTIVE

To examine the association between hospital-diagnosed atopic dermatitis and atrial fibrillation.

METHODS

Using linked population-based Danish registries, we identified persons with an inpatient or outpatient hospital diagnosis of atopic dermatitis during 1977-2013 and a comparison cohort individually matched to the atopic dermatitis cohort. We followed cohorts until death, emigration, atrial fibrillation diagnosis, or end of study (January 1, 2013). We compared 35-year risk of atrial fibrillation and estimated hazard ratios with 95% confidence intervals using Cox regression, adjusting for birth year and sex. We validated 100 atopic dermatitis diagnoses from a dermatologic department through medical record review.

RESULTS

We included 13,126 persons with atopic dermatitis and 124,211 comparators and followed them for a median of 19.3 years. The 35-year risk of atrial fibrillation was 0.81% and 0.67%, respectively. The positive predictive value of atopic dermatitis diagnoses was 99%. The hazard ratio was 1.2 (95% confidence interval 1.0-1.6) and remained increased after adjusting for various atrial fibrillation risk factors.

LIMITATIONS

Analyses were limited to persons with moderate-to-severe atopic dermatitis, and we had no lifestyle data.

CONCLUSION

Patients with hospital-diagnosed atopic dermatitis have a 20% increased long-term risk of atrial fibrillation, but the absolute risk remains low.

Mood Disorders and Risk of Herpes Zoster in 2 Population-Based Case-Control Studies in Denmark and the United Kingdom

We examined the association between mood disorders and risk of herpes zoster in two case-control studies using data from nationwide Danish registries and practices in the UK Clinical Practice Research Datalink. We included incident zoster cases diagnosed in general practice (using systemic antivirals as a proxy in Denmark) or hospital during 1997-2013 in Denmark (n = 190,671) and during 2000-2013 in the United Kingdom (n = 177,361). We risk-set sampled 4 matched population controls per case. Conditional logistic regression analyses adjusting for zoster risk factors showed that the odds ratios for previous mood disorder among cases versus controls were 1.15 (99% confidence interval (CI): 1.12, 1.19; prevalence 7.1% vs. 6.0%) in Denmark and 1.12 (99% CI: 1.11, 1.14; prevalence 31.6% vs. 29.2%) in the United Kingdom. In Denmark, odds ratios were higher for anxiety (1.23; 99% CI: 1.17, 1.30) and severe stress and adjustment disorder (1.24; 99% CI: 1.18, 1.30) than for depression (1.11; 99% CI: 1.07, 1.14). In the United Kingdom, odds ratios for these conditions were similar: 1.12 (99% CI: 1.10, 1.13), 1.12 (99% CI: 1.10, 1.14), and 1.14 (99% CI: 1.10, 1.19) for depression, anxiety, and severe stress and adjustment disorder, respectively. In conclusion, mood disorders were associated with an increased risk of zoster.

Partner Bereavement and Risk of Herpes Zoster: Results from Two Population-Based Case-Control Studies in Denmark and the United Kingdom

Background.

Psychological stress is commonly thought to increase the risk of herpes zoster by causing immunosuppression. However, epidemiological studies on the topic are sparse and inconsistent. We conducted 2 parallel case-control studies of the association between partner bereavement and risk of zoster using electronic healthcare data covering the entire Danish population and general practices in the UK Clinical Practice Research Datalink.

Methods.

We included patients with a zoster diagnosis from the primary care or hospital-based setting in 1997–2013 in Denmark (n = 190671) and 2000–2013 in the United Kingdom (n = 150207). We matched up to 4 controls to each case patient by age, sex, and general practice (United Kingdom only) using risk-set sampling. The date of diagnosis was the index date for case patients and their controls. We computed adjusted odds ratios with 99% confidence intervals for previous bereavement among case patients versus controls using conditional logistic regression with results from the 2 settings pooled using random-effects meta-analysis.

Results.

Overall, the adjusted odds ratios for the association between partner bereavement and zoster were 1.05 (99% confidence interval, 1.03–1.07) in Denmark and 1.01 (.98–1.05) in the United Kingdom. The pooled estimates were 0.72, 0.90, 1.10, 1.08, 1.02, 1.04, and 1.03 for bereavement within 0–7, 8–14, 15–30, 31–90, 91–365, 366–1095, and >1095 days before the index date, respectively.

Conclusions.

We found no consistent evidence of an increased risk of zoster after partner death. Initial fluctuations in estimates may be explained by delayed healthcare contact due to the loss.

Report from the first European Dermato-Epidemiology Network forum

The first European Dermato-Epidemiology Network (EDEN) forum was held on 30-31 March 2017 in Madrid, Spain. Dermatoepidemiology describes the study of causes, prevention, health services research and evaluation of interventions of skin diseases. EDEN aims to promote high-quality research, share expertise and facilitate collaboration. These aims were achieved during the EDEN forum by including a preconference course on skin cancer epidemiology; having excellent world-leading guest speakers on causality, quality of care, pharmacoepidemiology and missing data analysis; and including delegates who presented and discussed innovative research findings. The meeting brought together delegates from 11 different countries. We welcome everyone with an interest in clinical research and epidemiology related to skin disease to attend next year's meeting in March 2018 in Berlin.

Prevaccination epidemiology of herpes zoster in Denmark: Quantification of occurrence and risk factors

BACKGROUND

Herpes zoster (HZ) is a vaccine-preventable disease caused by reactivation of the varicella-zoster virus. Unfortunately, formulation of recommendations on routine immunization is hampered by a lack of data on disease burden, since most countries do not record cases of HZ in the general population. We developed and validated an algorithm to identify HZ based on routinely collected registry data and used it to quantify HZ occurrence and risk factors in Denmark prior to marketing of the HZ vaccine.

METHODS

We included patients aged ≥40years with a first-time systemic Acyclovir, Valacyclovir, or Famciclovir prescription or a hospital-based HZ diagnosis in the Danish nationwide health registries during 1997-2013. In a validation substudy (n=176), we computed the proportion of persons with HZ among patients who redeemed antiviral prescriptions. In a cohort study, we computed age-specific rates of HZ (45,297,258 person-years). In a case-control study, we then computed odds ratios (ORs) for common chronic diseases and immunosuppressive factors among HZ cases (n=189,025) vs. matched population controls (n=945,111).

RESULTS

Medical record review confirmed HZ in 87% (95% confidence interval: 79-93%) of persons ≥40years who dispensed antivirals at doses recommended for HZ. HZ rates increased from 2.15/1000 person-years in 40-year-olds to 9.45/1000 person-years in 95-year-olds. Rates were highest in women. HZ was diagnosed during hospitalization among 3.5%. As expected, persons with severe immunosuppressive conditions had the highest ORs of HZ (between 1.82 and 4.12), but various autoimmune diseases, asthma, chronic kidney disease, and inhaled glucocorticoids were also associated with increased ORs (between 1.06 and 1.64).

CONCLUSION

This algorithm is a valid tool for identifying HZ in routine healthcare data. It shows that HZ is common in Denmark, especially in patients with certain chronic conditions. Prioritized vaccination of such high-risk patients might be an option in countries considering alternatives to universal vaccination.

Hospital-based herpes zoster diagnoses in Denmark: rate, patient characteristics, and all-cause mortality

Background

Herpes zoster (HZ) may result in severe complications requiring hospital treatment, particularly in patients with comorbidity. Nevertheless, data on HZ from nationwide population-based hospital registries are sparse.

Methods

We conducted a cohort study describing first-time hospital-based (inpatient, outpatient, and emergency room) HZ diagnoses in the Danish National Patient Registry, 1994–2012. We computed the diagnosis rate; prevalence of demographic characteristics, comorbidities, and complications; length of hospital stay; and standardized mortality ratios (SMRs) using the Danish population as reference. We classified comorbidity using the Charlson Comorbidity Index (CCI) scoring system and categorized patients in groups of no (score 0), moderate (score 1), severe (score 2), and very severe comorbidity (score ≥3). In addition, we computed the prevalence of certain conditions associated with immune dysregulation (stem cell or bone marrow transplantation, solid organ transplantation, HIV infection, primary immunodeficiency, any cancer, and autoimmune diseases).

Results

The diagnosis rate increased almost exponentially from 6 to 91.9 per 100,000 person-years between age 50 and ≥90 years. The age-standardized rate was stable throughout the study period. The median length of hospital stay was 4 days (interquartile range: 1–8 days) for inpatients with HZ as the main reason for admission. According to the CCI, 44.3 % of patients had no comorbidity, 17.3 % moderate comorbidity, 17.4 % severe comorbidity, and 21.0 % very severe comorbidity. Comorbidities involving immune dysregulation, such as malignant (21 %) and autoimmune diseases (17 %), were particularly prevalent. Thirty percent had neurological, ophthalmic, or other complications. HZ was associated with increased all-cause mortality overall (SMR 1.8, 95 % CI: 1.7–1.8), but not in analyses restricted to patients without comorbidity (SMR 1.0, 95 % CI: 0.9–1.0).

Conclusions

This study provides estimates of the epidemiology of hospital-based (severe) HZ. The diagnosis rate increased substantially with age. Complications and comorbidities were prevalent, likely resulting in increased mortality.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1369-6) contains supplementary material, which is available to authorized users.