Atopic dermatitis and the metabolic syndrome: a cross‐sectional study of 116 816 patients

Genetic association of lipid and lipid-lowering drug target genes with atopic dermatitis: a drug target Mendelian randomization study

Observational studies suggest dyslipidemia as an atopic dermatitis (AD) risk factor and posit that lipid-lowering drugs may influence AD risk, but the causal link remains elusive. Mendelian randomization was applied to elucidate the causal role of serum lipids in AD and assess the therapeutic potential of lipid-lowering drug targets. Genetic variants related to serum lipid traits and lipid-lowering drug targets were sourced from the Global Lipid Genetics Consortium GWAS data. Comprehensive AD data were collated from the UK Biobank, FinnGen, and Biobank Japan. Colocalization, Summary-data-based Mendelian Randomization (SMR), and mediation analyses were utilized to validate the results and pinpoint potential mediators. Among assessed targets, only Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) was significantly linked to a reduced AD risk, corroborated across three separate AD cohorts. No association between serum lipid concentrations or other lipid-lowering drug targets and diminished AD risk was observed. Mediation analysis revealed that beta nerve growth factor (b-NGF) might mediate approximately 12.8% of PCSK9's influence on AD susceptibility. Our findings refute dyslipidemia's role in AD pathogenesis. Among explored lipid-lowering drug targets, PCSK9 stands out as a promising therapeutic agent for AD.

Interplay between diabetes mellitus and atopic dermatitis

Inflammatory dermatoses such as atopic dermatitis (AD) have long been linked to the pathogenesis of diabetes mellitus. Indeed, numerous studies show an increased risk of diabetes mellitus in individuals with AD although lower prevalence of diabetes mellitus is also observed in few studies. Though the underlying mechanisms accounting for the reciprocal influence between these two conditions are still unclear, the complex interplay between diabetes mellitus and AD is attributable, in part, to genetic and environmental factors, cytokines, epidermal dysfunction, as well as drugs used for the treatment of AD. Proper management of one condition can mitigate the other condition. In this review, we summarize the evidence of the interaction between diabetes mellitus and AD, and discuss the possible underlying mechanisms by which these two conditions influence each other.

Epidemiology and Risk Factors of Eosinophilic Esophagitis in Japan: A Population-Based Study

BACKGROUND & AIMS

Eosinophilic esophagitis (EoE) has been increasingly diagnosed globally. However, there have been few general population-based studies in Asia. The aim of this study was to investigate EoE epidemiology in the Japanese general population.

METHODS

We analyzed an employer-based health insurance claim database from January 2005 to September 2022. EoE cases were identified on the basis of the International Statistical Classification of Diseases and Health-related Problems, 10th Revision code, K20.0. We calculated the incidence and prevalence of EoE using Poisson regression and binomial distribution, respectively. Using 10 matched controls for each EoE case, a nested case-control study was performed to identify potential risk factors for EoE.

RESULTS

Of 15,200,895 individuals, 1010 EoE cases were identified. The incidence and prevalence of EoE were 2.82 (95% confidence interval [CI], 2.44-3.26) per 100,000 person-years and 10.68 (95% CI, 10.01-11.37) per 100,000 people in 2022, nearly 3 and 8 times as high as those in 2017, respectively. Smoking was associated with decreased risk of EoE (odds ratio [OR], 0.45, 0.36-0.56, P < .001), whereas alcohol consumption (OR, 1.51, 1.21-1.88, P < .001) was associated with increased risk of EoE along with several allergic conditions and psychiatric disorders. EoE was not related to either body mass index or lifestyle-related diseases such as hypertension, diabetes mellitus, hyperuricemia, and dyslipidemia.

CONCLUSIONS

The incidence and prevalence of EoE in Japan have steadily increased over the past 2 decades. Nevertheless, EoE remains less common in Japan compared with the United States and Western Europe. Factors contributing to the epidemiology of EoE on a global basis may improve our understanding of the contribution of genetic and environmental risk factors.

Abrocitinib-associated adverse events: a real-world pharmacovigilance study using the FAERS database

BACKGROUND

Atopic dermatitis (AD) is a common chronic inflammatory skin disease. Janus kinase (JAK) modulates cytokines involved in AD pathophysiology, and JAK inhibitors have emerged as effective pharmacotherapeutic remedies for AD. Abrocitinib, an oral selective inhibitor of JAK1, is indicated for the management of moderate-to-severe AD. The current study evaluated the adverse events (AEs) associated with abrocitinib in a real-world setting.

METHODS

To quantify the signals of abrocitinib-associated AEs, we used the US Food and Drug Administration Adverse Event Reporting System (FAERS) for this pharmacovigilance study with two established pharmacovigilance methods.

RESULTS

A total of 1071 AEs of abrocitinib were investigated as the primary suspected from the FAERS to detect and characterize relevant safety signals. The analysis revealed 85 signals for abrocitinib. The most common AE for abrocitinib was drug ineffective. The signal strength of eczema herpeticum was 515.87 (277.80-957.98) and 510.59 (5148.65) and exhibited the highest strength for abrocitinib. Rare AEs such as aggravated condition, pruritus, and hypersensitivity were not listed on the label, and attention to these AEs is required.

CONCLUSION

The analysis of the AE signals may provide support for clinical monitoring and risk identification of abrocitinib.

Increased prevalence of metabolic syndrome and non-alcoholic fatty liver disease in children with atopic dermatitis: A case-control study from northern India

BACKGROUND/OBJECTIVES

Atopic dermatitis (AD) is a chronic inflammatory skin disorder that affects children worldwide, with potential associations to metabolic syndrome (MetS) and non-alcoholic fatty liver disease (NAFLD). Limited research exists on the interplay between AD, MetS, and NAFLD in the pediatric population. This study aimed to investigate the prevalence and potential relationships among AD, MetS, and NAFLD in children.

METHODS

A case-control study design was employed, recruiting 50 children with AD (median age: 9.5 years) and 50 age- and sex-matched healthy controls (median age: 11.5 years, p = .051). Data on demographic characteristics, clinical features, disease severity, treatment history, anthropometric measurements, and laboratory evaluations were collected. MetS and NAFLD were diagnosed based on established criteria.

RESULTS

The prevalence of MetS was significantly higher in children with AD compared with controls (24% vs. 2%, p = .002). Significant differences for systolic blood pressure (p < .001), diastolic blood pressure (p = .012), and waist circumference (p = .040) were observed between AD patients and controls. Children with AD had higher triglyceride levels (p = .005). NAFLD was exclusively seen in moderate to severe AD cases (6% vs. 0%, p = .242). AD severity showed associations with increased body mass index (p = .020).

CONCLUSION

This study highlights the increased prevalence of MetS and the potential association with NAFLD in children with AD. The findings suggest that AD may contribute to the development of metabolic abnormalities at an early age. Further research is needed to elucidate the underlying mechanisms and explore preventive strategies for these interconnected conditions.

Comparison of metabolic and neurological comorbidities in Asian patients with psoriasis and atopic dermatitis

Although various comorbidities have been noted to be associated with atopic dermatitis (AD) and psoriasis, few studies have compared comorbidities between the two diseases, and little is known about whether these comorbidities vary by the subtypes of psoriasis. In this study of 1:1 age- and sex-matched pair analysis between patients diagnosed with either psoriasis or AD at Asan Medical Center between 1991 and 2020, comorbidities, as determined by the International Classification of Diseases-10 codes, and likelihood ratios of metabolic and neurologic comorbidities in psoriasis compared with AD were studied using a logistic regression model. Among a total of 14,128 patients, the psoriasis group had higher odds of obesity (odds ratio [95% confidence interval]: 1.49 [1.34-1.66]), hypertension (1.14 [1.03-1.26]), diabetes mellitus (1.46 [1.29-1.66]), chronic kidney disease (1.59 [1.22-2.08]), and Parkinson's disease (2.1 [1.15-3.83]) than the AD group. Subgroup analysis revealed that patients with plaque psoriasis had higher odds of obesity (1.18 [1.05-1.33]), hypertension (1.18 [1.06-1.32]), diabetes mellitus (1.53 [1.34-1.75]), chronic kidney disease (1.66 [1.26-2.17]), and Parkinson's disease (2.12 [1.16-3.88]) compared with AD. Meanwhile, guttate psoriasis was associated with higher odds of dementia (3.63 [1.06-12.40]) and patients with generalized pustular psoriasis showed higher odds of diabetes mellitus (5.42 [1.56-18.83]) compared with AD. In conclusion, Asian patients with all types of psoriasis should be closely monitored for the development of metabolic and neurologic diseases, especially men and those aged ≥ 40 years.

Childhood atopic dermatitis is associated with cardiovascular risk factors in young adulthood-A population-based cohort study

BACKGROUND

Studies have indicated that atopic dermatitis (AD) is associated with an increased risk of cardiovascular disease (CVD). However, data are conflicting. Furthermore, the longitudinal effect of childhood AD on cardiovascular risk factors in young adulthood is less investigated.

OBJECTIVES

To assess associations between AD in childhood and CVD risk factors in young adulthood.

METHODS

The study encompasses longitudinal data from a population-based birth cohort. Participants with data up to age 24 years were included (n = 2270). The primary outcomes were body mass index (BMI), waist circumference (WC), body fat per cent (BF%) and blood pressure (BP) at 24 years. The secondary outcome was blood lipids. Severe AD was defined as AD in combination with sleep disturbance due to itching.

RESULTS

In total, 18.6% (n = 420) had AD at 24 years. Males with AD had higher BMI (βAdj. 0.81, 95% CI 0.15-1.47), BF% (βAdj. 1.19, 95% CI 0.09-2.29), systolic BP (βAdj. 1.92, 95% CI 0.02-3.82), total cholesterol (βAdj. 0.14, 95% CI 0.00-0.28) and LDL cholesterol (βAdj. 0.15, 95% CI 0.02-0.27) compared with males without AD. No associations were seen in females. Current AD with prepubertal onset was associated with increased BMI in both males (βAdj. 0.89, 95% CI 0.11-1.67) and females (βAdj. 0.72, 95% CI 0.11-1.33). At 24 years, 23.1% (n = 97) of all with AD, had severe disease, which was significantly associated with overweight in both sexes, with BMI (βAdj. 1.83, 95% CI 0.72-2.94), WC (βAdj. 4.03, 95% CI 1.54-6.52) and BF% (βAdj. 2.49, 95% CI 0.60-4.39) in females and with BF% (βAdj. 2.96, 95% CI 0.23-5.69) in males, compared with peers with mild to moderate AD.

CONCLUSION

AD in males appears to be associated with CVD risk factors in young adulthood. The duration and severity of AD seem to be of importance in both sexes.

Lipid Alterations and Metabolism Disturbances in Selected Inflammatory Skin Diseases

Lipidomics is a term used to define the field that analyzes the structure, functions, and interactions of lipids. Inflammatory dermatoses and lipid disturbances are interrelated, especially due to chronic inflammatory conditions. This review discusses lipidomics in selected inflammatory skin diseases: psoriasis, lichen planus, and atopic dermatitis, as well as the less commonly mentioned hidradenitis suppurativa, rosacea, and acne vulgaris. Lipid homeostasis disorders are common; they are especially well-documented in psoriasis, lichen planus, and atopic dermatitis. Future studies are required for better insight into this issue, particularly on the skin lipidome. Understanding lipidomics, in particular skin diseases, increases our knowledge about their pathogenesis, and may become useful in adjusting tailored management for each patient as well establishing prognosis. Noteworthily, it seems advisable to alert doctors to the need to analyze lipid parameters and the complications of abnormal lipid metabolism in dermatological patients, which could decrease their comorbidities and improve the life quality and health condition of dermatological patients.

Skin Dialogues in Atopic Dermatitis

Atopic dermatitis (AD) is a chronic skin disorder associated with significant quality-of-life impairment and increased risk for allergic and non-allergic comorbidities. The aim of this review is to elucidate the connection between AD and most common comorbidities, as this requires a holistic and multidisciplinary approach. Advances in understanding these associations could lead to the development of highly effective and targeted treatments.

Hormonal Effects on Asthma, Rhinitis, and Eczema

Hormones significantly influence the pathogenesis of asthma, rhinitis, and eczema. This review aims to summarize relevant clinical considerations for practicing allergists and immunologists. The first section reviews the effects of sex hormones: estrogen, progesterone, and testosterone. The second concerns insulin production in the context of type 1 and type 2 diabetes. The third concludes with a discussion of thyroid and adrenal pathology in relationship to asthma, rhinitis, and eczema.

Atopic dermatitis: pathomechanisms and lessons learned from novel systemic therapeutic options

Atopic dermatitis (AD) is a chronic, heterogenous, inflammatory skin disorder associated with a high skin-related health burden, typically starting in childhood and often persisting into adulthood. AD is characterized by a wide range of clinical phenotypes, reflecting multiple underlying pathophysiological mechanisms and interactions between genetics, immune system dysregulation, and environmental factors. In this review, we describe the diverse cellular and molecular mechanisms involved in AD, including the critical role of T cell-driven inflammation, primarily via T helper (Th) 2- and Th17-derived cytokines, many of which are mediated by the Janus kinase (JAK) signaling pathway. These local inflammatory processes interact with sensory neuronal pathways, contributing to the clinical manifestations of AD, including itch, pain, and sleep disturbance. The recent elucidation of the molecular pathways involved in AD has allowed treatment strategies to evolve from broad-acting systemic immunosuppressive therapies to more targeted agents, including JAK inhibitors and cytokine-specific biologic agents. Evidence from the clinical development of these targeted therapies has reinforced and expanded our understanding of the pathophysiological mechanisms underlying AD and holds promise for individualized treatment strategies tailored to specific AD subtypes.

Does weight loss lead to improvement of dermatological conditions: What is the evidence?

Obese and overweight individuals may have a wide gamut of cutaneous features and can have more severe manifestations of multiple dermatological conditions. There have been multiple expert opinions on the favorable effects of weight reduction in improving skin conditions. Over the past decade, there have been few studies evaluating the response of exercise and other modes of weight loss on various dermatoses such as psoriasis, acne, hidradenitis suppurativa, acanthosis nigricans. In this review, we have attempted to provide a summary of the benefits of reduction of body weight on various skin aliments.

Moderate-to-severe atopic dermatitis and lifestyle factors in the Dutch general population

Background

Studies on the association between severity of atopic dermatitis (AD) and lifestyle factors in adults have not been conducted in the Netherlands to date.

Aim

To explore the association between moderate to severe AD and lifestyle factors in adults in the Dutch general population.

Methods

We conducted this cross‐sectional study within the Lifelines Cohort Study by sending a digital AD questionnaire to 135 950 adults in 2020. We extracted data on lifestyle factors from baseline, collected between 2006 and 2013. We analysed the association between lifestyle factors and presence of AD of any severity and of moderate to severe AD, using binary logistic regression and linear regression models.

Results

We enrolled 56 896 participants (mean age 55.8 years, 39.7% males). The lifetime prevalence of self‐reported physician‐diagnosed AD was 9.1%, and the point prevalence of any AD and of moderate to severe AD was 3.3% and 2.3%, respectively. We found that moderate to severe AD was associated with smoking habit of > 15 pack‐years, alcohol consumption of > 2 drinks per day, chronic stress, Class I obesity, and both shorter and longer sleep duration. Moreover, we found dose–response associations with increases in smoking pack‐years and level of chronic stress. We observed no associations with abdominal obesity, physical activity, diet quality or a vegetarian/vegan diet.

Conclusion

We found associations between moderate to severe AD and some modifiable lifestyle factors. Our findings indicate that more screening and counselling for lifestyle factors, particularly smoking, alcohol use, stress, obesity and sleep disturbances, appears warranted in patients with moderate to severe AD. Further longitudinal studies are required to better characterize the direction of these associations and to develop strategies for prevention.

Association Between Atopic Dermatitis, Asthma, and Serum Lipids: A UK Biobank Based Observational Study and Mendelian Randomization Analysis

Background

Both atopic diseases and dysregulation of serum lipids (SLs) add to significant health burden, but evidences about their association are inconsistent.

Objective

This work is to evaluate the association between asthma/atopic dermatitis (AD) and SLs and investigate the potential causal relationship.

Methods

A large-scale cross-sectional study based on the UK Biobank (UKB) and then examined the casual relationships between SLs with asthma/AD based on a Mendelian randomization (MR) analysis.

Results

A total of 502,505 participants were included in analysis. After full adjustment, AD was associated with lower TG (β = −0.006; 95%CI, −0.010 to −0.002; P = 0.006), lower LDL (β = −0.004; 95%CI, −0.006 to −0.002, P < 0.001), and lower TC (β = −0.004; 95%CI, −0.005 to −0.002; P < 0.001) but insignificantly correlated to HDL (P = 0.794). Asthma was also inversely correlated to TG (β = −0.005; 95%CI, = −0.007 to −0.003; < 0.001), LDL (β = −0.003; 95%CI, −0.004 to −0.002; P < 0.001), and TC (β = −0.002; 95%CI, −0.003 to −0.002; P < 0.001), but was positively correlated to HDL (β = 0.004; 95%CI, 0.003 to 0.005; P < 0.001), respectively. In subsequent MR analysis, both allergic diseases and asthma showed a protective effect on TC. Allergic diseases, asthma, and AD all showed a negative effect on LDL.

Conclusion

Collectively, we identify a protective causal effect of allergic diseases on serum lipids, as well as a potentially positive association of HDL with asthma. Owing to the largest sample size and the application of IVs in causal inference, this study will provide a robust evidence for the management of asthma and AD and the prevention of dyslipidemia.

Atopic Dermatitis: The Fate of the Fat

Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease in which dry and itchy skin may develop into skin lesions. AD has a strong genetic component, as children from parents with AD have a two-fold increased chance of developing the disease. Genetic risk loci and epigenetic modifications reported in AD mainly locate to genes involved in the immune response and epidermal barrier function. However, AD pathogenesis cannot be fully explained by (epi)genetic factors since environmental triggers such as stress, pollution, microbiota, climate, and allergens also play a crucial role. Alterations of the epidermal barrier in AD, observed at all stages of the disease and which precede the development of overt skin inflammation, manifest as: dry skin; epidermal ultrastructural abnormalities, notably anomalies of the lamellar body cargo system; and abnormal epidermal lipid composition, including shorter fatty acid moieties in several lipid classes, such as ceramides and free fatty acids. Thus, a compelling question is whether AD is primarily a lipid disorder evolving into a chronic inflammatory disease due to genetic susceptibility loci in immunogenic genes. In this review, we focus on lipid abnormalities observed in the epidermis and blood of AD patients and evaluate their primary role in eliciting an inflammatory response.

Metabolic and inflammatory biomarkers in children with atopic dermatitis (AD): a case-control study

Background

Atopic dermatitis is characterized by impaired skin barrier and altered cutaneous innate immunity. The estimated prevalence among Egyptian children was 10–12%. Several studies suggest that it may be associated with systemic comorbidities other than the spectrum of atopy, such as metabolic syndrome and other inflammatory conditions. The aim of this study is to compare the profile of systemic conditions of diabetes, dyslipidemia, and multiple inflammatory markers in children with and without diagnosed atopic dermatitis.

Methods

One hundred atopic dermatitis patients and 101 normal controls were collected from outpatient clinic based on their clinical condition, both had measurement of body mass index, blood sugar, serum insulin, lipid profile, C reactive protein, and gamma-glutamyl transferase.

Results

Children diagnosed with atopic dermatitis had significantly higher levels of body mass index (34.7 ± 5.7 vs 26.1 ± 4.9), fasting glucose (143.2 ± 30.3 vs 100.8 ± 16.0), serum insulin (11.3 ± 4.4 vs. 4.6 ± 3.0), serum triglycerides (194.1 ± 38.1 vs 156.2 ± 31.6), total cholesterol (198.4 ± 27.7 vs 163.7 ± 27.7), alkaline phosphatase (229.4 ± 89.8 vs. 189.4 ± 46.8), and gamma-glutamyl transferase (54.7 ± 19.9 vs 34.3 ± 9.5), C-reactive protein level was approximately four times higher (19.9 ± 13.2 vs 5.1 ± 3.4) and the immunoglobulin E level was approximately 10 times higher (2050.3 ± 843.8 vs 252.7 ± 103.1) than in controls

Conclusion

We found a positive relationship of atopic dermatitis with both diabetes and hyperlipidemia among children, and positive dose-response relationship of several non-traditional biomarkers of C-reactive protein, gamma-glutamyl transferase, and alkaline phosphatase with the presence and severity of atopic dermatitis.

Advances in Atopic Dermatitis in 2019-2020: Endotypes from skin barrier, ethnicity, properties of antigen, cytokine profiles, microbiome, and engagement of immune cells

Key research advances in atopic dermatitis (AD) suggest the complexity of its endotypes. A comprehensive serum biomarker panel revealed at least four types of AD. Some represent classic TH2-dominant AD with filaggrin mutations commonly reported in Europeans, a simultaneously activated multipolar axes of cytokines often reported in Asians, and an intrinsic type characterized by TH2-inferiority. Innate lymphoid cells, including NK cells, NKT cells, and fibroblasts, play a role in AD development and heterogeneity. Here, we discuss the endotypes of AD from the perspective of antigen types (hapten vs. protein antigens), barrier function, and a novel set of immune cells. Endotypic stratification of AD may lead to the development of customized therapeutic strategies in the future.

Cardiovascular comorbidities of atopic dermatitis: using National Health Insurance data in Korea

Background

It is well known that atopic dermatitis (AD) is associated with other allergic diseases. Recentely, links to diseases other than allergic disease have also been actively studied. Among them, the results of studies regarding AD comorbidities, especially cardiovascular disease (CVD), have varied from country to country.

Objective

To analyze whether the risk of CVD is different between AD patients and healthy controls using Korean National Health Insurance Data.

Methods

We obtained data from 2005 to 2016 from the Korean National Health Insurance Research Database. Patients with one AD code and two AD-related tests codes were selected as AD patients, and age-and sex-matched controls to the AD patients were selected from among those without AD (1:5). Each group was investigated for accompanying metabolic syndrome (which contains hypertension, type 2 diabetes, and hyperlipidemia) and CVD (angina, myocardial infarction, peripheral vascular disease, and stroke) using ICD 10 codes.

Results

The incidence of metabolic diseases and CVD were significantly different between the AD and control groups. Using multivariable Cox regression, differences were adjusted for sex, age, and other CVD and metabolic diseases. As a result, not only metabolic disease, but also the CVD risk of AD patients was significantly higher than that of the control group. Patients with AD had as significantly higher risk of hyperlipidemia (hazard ratio [HR] = 33.02, p < 0.001), hypertension (HR = 4.86, p < 0.001), and type 2 diabetes (HR = 2.96, p < 0.001). AD patients also had a higher risk of stroke (HR = 10.61, p < 0.001), myocardial infarction (HR = 9.43, p < 0.001), angina (HR = 5.99, p < 0.001), and peripheral vascular disease (HR = 2.46, p < 0.001). Besides hyperlipidemia, there was no difference in risk according to AD severity.

Conclusion

Patients with AD have a greater risk of CVD than those without AD.

Association between Atopic Dermatitis and Hypertension: A Systematic Review and Meta-Analysis

BACKGROUND

Previous studies found conflicting results about the association of atopic dermatitis (AD) with hypertension.

OBJECTIVES

Determine whether AD and AD severity are associated with hypertension.

METHODS

A systematic review was performed of published studies in MEDLINE, EMBASE, Scopus, Web of Science, and GREAT databases. At least 2 reviewers conducted title/abstract, full-text review, and data extraction. Quality of evidence was assessed using the Newcastle-Ottawa Scale.

RESULTS

Fifty-one studies met inclusion criteria; 19 had sufficient data for meta-analysis. AD was associated with higher odds of hypertension compared to healthy controls (increased in 9 of 16 studies; pooled prevalence: 16.4% vs 13.8%; random-effects regression, pooled unadjusted odds ratio [OR][95% confidence interval <CI95>]: 1.16 [1.04-1.30]), but lower odds of hypertension compared to psoriasis (decreased in 5 of 8 studies; 15.4% vs 24.8%; 0.53 [0.37-0.76]). In particular, moderate-severe AD were associated with hypertension compared to healthy controls (increased in 4 of 6 studies; 24.9% vs 14.7%; 2.33 [1.10-4.94]). Hypertension was commonly reported as an adverse-event secondary to AD treatments, particularly systemic cyclosporine A. Limitations include lack of longitudinal studies or individual-level data and potential confounding.

CONCLUSIONS

AD, particularly moderate-to-severe disease, was associated with increased hypertension compared to healthy controls, but lower odds than psoriasis.

Atopic Dermatitis and Infertility: A Nationwide Retrospective Cohort Study

BACKGROUND

Given that common pathophysiological factors play a role in atopic dermatitis (AD) and infertility, we assumed that the 2 conditions might demonstrate an epidemiological association. Large-scale epidemiological data on this topic are lacking.

OBJECTIVES

The aim of this work was to evaluate the potential association between AD and infertility in a broad community-based population.

METHODS

A nationwide retrospective cohort study was conducted, analyzing the association between AD and infertility. We compared AD patients diagnosed by a dermatologist between 2002 and 2018 and a matched control group. The study population was subdivided according to age into adults (age ≥18 years) and children (age <18 years), and was further subdivided according to AD severity, classified as either mild or moderate-to-severe according to AD-related drug use and healthcare services utilization.

RESULTS

The study included 127,150 patients with AD and 127,071 comparison enrollees. AD was associated with a higher prevalence of infertility than that of the control group (1.4 and 1.1%, respectively). The prevalence of infertility, per 1,000 patient-years, was increased in patients with AD compared to that of the control group (2.17 and 1.7, respectively). Multivariate analysis for infertility demonstrated that AD was a key risk factor for infertility in both males and females with mild AD and moderate-to-severe AD.

CONCLUSION

A significant association between AD and infertility was observed. This association suggests that infertility may be an additional manifestation of AD. Further studies are warranted to evaluate the impact of AD management in the setting of infertility and vice versa.

Atopic dermatitis and dementia risk: A nationwide longitudinal study

BACKGROUND

Retrospective studies have suggested that patients with dementia have higher prevalence of atopic dermatitis (AD) than those without dementia. However, the temporal association of AD with subsequent dementia remains unknown.

OBJECTIVE

To assess the temporal association of AD with subsequent dementia.

METHODS

We included data of patients with AD aged 45 years and older (n = 1059) and 1:10 age, sex, residence, income, and dementia-related comorbidity-matched controls (n = 10,590) from the Taiwan National Health Insurance Research Database and reviewed their subsequent dementia development from the enrollment date to the end of 2013.

RESULTS

After adjustments for dementia-related comorbidities, patients with AD were found to be more likely to develop any dementia (hazard ratio [HR], 2.02; 95% confidence interval [CI], 1.24-3.29), particularly Alzheimer's disease (HR, 3.74; 95% CI, 1.17-11.97), during the follow-up period than those in the control group. Moderate-to-severe AD was associated with a high subsequent dementia risk (HR, 4.64; 95% CI, 2.58-8.33). Sensitivity analyses with the exclusion of the first 3 (HR, 2.20; 95% CI, 1.28-3.80) or 5 (HR, 2.05; 95% CI, 1.08-3.89) years of observation revealed consistent findings.

CONCLUSION

AD may be an independent risk factor for new-onset dementia. Clinicians may monitor the trajectory of neurocognitive function among elderly patients with AD. Additional studies elucidating the pathomechanisms between AD and subsequent dementia are warranted.

Involvement of RAGE and Oxidative Stress in Inflammatory and Infectious Skin Diseases

The surface receptor for advanced glycosylation end-products (RAGE) and its soluble (sRAGE) and endogenous secretory (EN-RAGE) forms belong to the superfamily of toll-like receptors and play important roles in inflammation and autoimmunity, directly or through binding with advanced glycosylation end-products (AGE) and advanced oxidation protein products (AOPP). We reviewed the literature on the role of RAGE in skin diseases. Research in this field is still rather limited (28 articles) but suggests the involvement of RAGE and RAGE-related pathways in chronic inflammatory diseases (lupus, psoriasis, atopic dermatitis, and lichen planus), infectious diseases (leprosy, Staphylococcus aureus-induced skin lesions), alterations of the repairing processes in diabetic skin, systemic sclerosis, and ulcers. These data prompt further research in this field, which not only will be useful to better understand the pathogenetic mechanisms of diseases, but is also likely to have intriguing clinical implications. Indeed, when their role in the complex and multifactorial inflammatory balance will be adequately defined, RAGE and related molecules could be used as markers of disease severity and/or response to treatment. Moreover, future promising therapeutic perspectives could be topical administration of some of these molecules (e.g., sRAGE) to modulate local inflammatory response and/or the development of anti-RAGE antibodies for systemic treatment.

Acne Keloidalis Nuchae and the Metabolic Syndrome: A Population-Based Study

BACKGROUND

The association between acne keloidalis nuchae (AKN) and the metabolic syndrome (MS) has been reported anecdotally. However, it is yet to be investigated in the setting of controlled studies, leaving this topic inconclusive in the current literature.

OBJECTIVE

The aim was to estimate the association between AKN and the MS and its components, utilizing one of the largest cohorts of patients with AKN.

METHODS

A retrospective, population-based, cross-sectional study was performed between 2005 and 2018. We utilized the database of Clalit Health Services, the largest public healthcare provider organization in Israel. The current study encompassed data collected from general community clinics, primary care, and referral centers, as well as from ambulatory and hospital care.

RESULTS

A total of 2677 patients with AKN and 13,190 controls were included. The prevalence of the MS was greater in patients with AKN than in control subjects (16.1% vs. 6.6%, respectively; odds ratio [OR] 2.72; 95% confidence interval [CI] 2.40-3.08; P < 0.001). Obesity demonstrated the strongest association with AKN (OR 3.00; 95% CI 2.75-3.28), followed by type 2 diabetes mellitus (OR 2.47; 95% CI 2.20-2.77), hypertension (OR 1.82; 95% CI 1.63-2.05), and dyslipidemia (OR 1.60; 95% CI 1.46-1.75). Estimates were not altered significantly after controlling for putative confounding factors.

CONCLUSIONS

A strong association was observed between AKN and the MS on the one hand, and with every one of its four components on the other. Physicians treating patients with AKN should be aware of this possible comorbidity. Patients with AKN should be carefully assessed for comorbid metabolic disorders.

Investigating causal relationships between Body Mass Index and risk of atopic dermatitis: a Mendelian randomization analysis

Population studies suggest that atopic dermatitis (AD) is associated with an increased risk of obesity, however a causal relationship between these two conditions remains to be established. We therefore use Mendelian randomization (MR) to evaluate whether obesity and AD are causally interlinked. We used summary statistics extracted from genome wide association studies of Body Mass Index (BMI) and AD. MR analysis was performed in both directions to establish the direction of causality between BMI and AD. We find that genetically determined increase in adiposity is associated with increased risk of AD (odds ratio of AD 1.08 [95% CI 1.01 to 1.14; p = 0.015] per unit increase in BMI). Conversely, genetically determined increased risk of AD is not associated with a higher BMI (change in BMI attributable to AD based on genetic information: 0.00; 95% CI − 0.02 to 0.02; p = 0.862). There was no evidence for confounding of these genetic analyses by horizontal pleiotropy. Our results indicate that the association of AD with obesity is likely to reflect a causal role for adiposity in the development of AD. Our findings enhance understanding of the etiology of AD, and the basis for experimental studies to evaluate the mechanistic pathways by which adiposity promotes AD.

Risk of metabolic syndrome in patients with lichen planus: A systematic review and meta-analysis

Background

Studies have investigated whether patients with lichen planus are at a high risk of metabolic syndrome; however, currently, no conclusive data are available in this regard.

Objective

This meta-analysis was performed to analyze the published literature investigating the association between metabolic syndrome and lichen planus.

Method

Two reviewers independently searched 4 databases (PubMed, Embase, the Cochrane Library and Web of Science) for observational studies assessing the prevalence of metabolic syndrome in patients with lichen planus. Review Manager 5.3 software was used to statistically analyze the data.

Results

200 relevant articles were searched. After a further reading, 12 studies with 1422 participants (715 with LP and 707 controls) fulfilled the eligibility criteria. Overall, the pooled odds ratio based on random effects analysis was 2.81 (95% confidence interval: 1.79–4.41, P<0.00001). This meta-analysis shows that compared with the general population, patients with lichen planus are more likely to develop metabolic syndrome. Subgroup analysis of prevalence of metabolic syndrome showed higher odds ratio in studies using International Diabetes Federation diagnostic criteria (odds ratio 4.65) and the Harmonized criteria (odds ratio 26.62) than studies using National Cholesterol Education Program Adult Treatment Panel III criteria (odds ratio 1.75), and thus might be more appropriate for diagnosing metabolic syndrome.

Conclusions

This meta-analysis shows that compared with the general population, patients with lichen planus are more likely to develop metabolic syndrome. Therefore, early diagnosis and prompt initiation of first-line therapy for metabolic disorders are important in patients with lichen planus.

Comorbidités de la dermatite atopique

Atopic dermatitis is associated with an increased risk of asthma (10 to 30% according to age), allergic rhinitis and conjunctivitis and food allergy. Other comorbidiies are globally lest frequent than in psoriasis. There is no increased risk of solid cancer. Smoking is a major confounding factor that has to be taken into account. Obesity and metabolic syndrome are more frequent and there is a moderately increased cardiovascular risk in severe forms of atopic dermatitis. There is a clear-cut increased risk of vitiligo and alopecia areata and a lower risk of other auto-immune diseases, including type I diabetes in children. There is a higher risk of cutaneous but not extra-cutaneous bacterial and viral infections, and increased frequency of contact dermatitis and urticaria. Severe atopic dermatitis is associated with psychiatric comorbidities, like attention disorders/hyperactivity, depression and suicidal ideas. © 2019 Elsevier Masson SAS. All rights reserved.

Prevalence and Comorbidity of Atopic Dermatitis in Children: A Large-Scale Population Study Based on Real-World Data

This study aimed at exploring atopic dermatitis (AD) prevalence in children and exhaustively analyzing their comorbidity. We conducted a descriptive analysis of their socio-demographic and comorbidity characteristics in the EpiChron Cohort (Aragón, Spain). Adjusted odds ratios (OR) were calculated for each comorbidity using logistic regression models. In total, 33,591 children had a diagnosis of AD, resulting in an overall prevalence of 15.5%. AD prevalence was higher in girls compared to boys, in 3–9-year-olds compared to children of other ages, and in Spanish children compared to those of other nationalities. Multimorbidity was present in 43% of children, with the most frequent chronic comorbidities being asthma (13.1%), psychosocial disorders (7.9%), and visual impairment (7.8%). Many diseases were, regardless of their prevalence, statistically associated with AD. The strongest associations (odds ratio (OR) (95% confidence interval (CI))) were found in asthma (2.10 (2.02–2.17)), allergic rhinitis (2.00 (1.91–2.10)), and irritable bowel syndrome (1.90 (1.56–2.31)). A better understanding of the array of comorbidities associated with AD in children might help improve their clinical management. Future longitudinal studies are encouraged to shed light on the potential underlying pathophysiological mechanisms involved in the identified associations.

Is Gout Associated with Pyoderma Gangrenosum? A Population-Based Case-Control Study

The coexistence of pyoderma gangrenosum (PG) and gout has been reported in individual patients; however, the association between these conditions has not been investigated. We aimed to assess the association between PG and gout and to examine whether the presence of gout predisposes to the development of PG. A population-based case-control study was conducted comparing PG patients (n = 302) with age-, sex-, and ethnicity-matched control subjects (n = 1497) with respect to the presence of preceding gout. Logistic regression models were utilized for univariate and multivariate analyses. The prevalence of preceding gout was greater in patients with PG than in control subjects (3.7% vs. 0.7%, respectively; p < 0.001). Gout was associated with a more than fivefold increase in the risk of PG (OR, 5.15; 95% CI, 2.21-11.98). After adjusting for confounding factors, gout emerged as a significant independent predictor of PG (adjusted OR, 4.08; 95% CI, 1.69-9.80). Gout preceded the diagnosis of PG by a median latency of 4.6 years. Patients with gout-associated PG were older, predominantly male, and had a higher prevalence of metabolic syndrome than other patients with PG. In conclusion, gout increases the risk of developing PG by more than fivefold. Physicians managing patients with gout and PG should be aware of this emerging association.

Atopic Dermatitis and Comorbidity

Atopic dermatitis is the most common chronic inflammatory skin disease. It is often the first indicator of allergic diseases, and a certain percentage of patients are affected by allergic rhinitis and/or asthma as a consequence. The study aimed to investigate the link between atopic dermatitis and comorbidity in family medicine. In the specialist family medicine practice Osijek, a retrospective study was conducted in the period from January 1, 2016 to July 1, 2017 on the percentage of patients with atopic dermatitis in the total number of patients, and their comorbid diseases. The data source was the E-chart. The results showed that 195 (10.53%) out of 2056 patients had atopic dermatitis, 80 (41%) patients had atopic dermatitis and allergic rhinitis, 34 (17.4%) asthma, 132 (67.7%) infections, 59 (30.3%) gastrointestinal disturbances, and 68 (34.3%) had mental disorders. Patients up to 18 years old were more likely to have infections, and adult patients were exposed to chronic stress. The most commonly used drug was loratadine (60.5%), while mometasone was the most commonly administered topical drug (40%). The result of this research showed the steps of the ˝atopic march˝. Atopic dermatitis is followed by changes in the skin and its progression to other organ systems in most of the patients.

Targeting T Cell Metabolism in Inflammatory Skin Disease

A properly functioning T cell compartment is crucial to protect the host from infections, tumors, and environmental substances. In recent years, it has become increasingly clear that the processes underlying proper T cell activation, proliferation, and differentiation require well-tuned and dynamic changes in T cell metabolism. Thus, proper metabolic reprogramming in T cells is crucial to ensure proper immunity in the context of infection and anti-tumor immunity. Conversely, aberrant regulation of T cell metabolism can impair T cell function and thereby contribute to T cell-mediated disease. In this review, the relevance of recent insights into T cell metabolism for prototypical T cell-mediated skin diseases will be discussed and their therapeutic potential will be outlined. First, the major modules of T cell metabolism are summarized. Then, the importance of T cell metabolism for T cell-mediated skin diseases such as psoriasis and allergic contact dermatitis is discussed, based on the current state of our understanding thereof. Finally, novel therapeutic opportunities for inflammatory skin disease that might emerge from investigations in T cell metabolism are outlined.