Does having siblings really protect against childhood atopic diseases? A total population and within-family analysis.

The association between having older siblings and decreased risk for atopic symptoms is well-established. This has been interpreted as evidence for the microbiota hypothesis, i.e. that increased early-childhood microbial exposure caused by siblings protects from immune hypersensitivities. However, possible confounders of the association have received little attention. We used register data on Finnish cohorts born in 1995-2004 (N = 559,077) to assess medication purchases for atopic diseases: antihistamines, eczema medication, asthma medication and Epinephrine. We modelled the probability of atopic medication purchases at ages 0-15 by birth order controlling for important observed confounders and all unobserved genetic and environmental characteristics shared by siblings in a within-family fixed effects model. We further studied medication purchases among first-borns according to the age difference with younger siblings to assess whether having younger siblings in early childhood is beneficial. Having older siblings was associated with a lower probability of atopic medication purchases. Compared to first-borns, the probability was 10-20% lower among second-borns, 20-40% lower among third-borns, and 30-70% lower among subsequent children, depending on medication type. Confounding accounted for up to 75% of these differences, particularly for asthma and eczema medication, but significant differences by birth order remained across all medication types. Among first-borns, a smaller age difference with younger siblings was related to a lower likelihood of atopic medication use. Our results, based on designs that account for unobserved confounding, show that exposure to siblings in early childhood, protects from atopic diseases, and thus strongly support the microbiota hypothesis.

Association between dietary antioxidants intake and childhood eczema: results from the NHANES database.

BACKGROUND: High dietary intake of antioxidants reduces the risk of allergic sensitization in children. However, there was no sufficient evidence for the effect of dietary antioxidants intake on childhood eczema. Herein, this study aimed to explore the roles of different dietary antioxidants in childhood eczema. METHODS: Data of 2305 children and adolescents aged < 18 years old were extracted from the National Health and Nutrition Examination Survey database in 2005-2006 in this cross-sectional study. The associations between dietary antioxidants intake and childhood eczema were explored using univariate and multivariate logistic regression analyses, with odds ratios (ORs) and confidence intervals (CIs). Subgroup analyses based on age and gender were also performed. RESULTS: A total of 268 (11.6%) children had eczema. After adjusting for covariates, we found no significant associations between dietary intake of ß-carotene, vitamin C, selenium (Se), and retinol and childhood eczema. However, compared with children and adolescents whose dietary zinc (Zn) intake < 7.47 mg, those who had dietary Zn intake level ≥ 11.83 mg seemed to have lower odds of eczema [OR 0.45, 95% CI 0.28-0.73]. In addition, subgroup analysis showed that especially in children and adolescents aged 1-11 years old, whatever the gender, a higher dietary intake level of Zn may benefit childhood eczema (all P < 0.05). CONCLUSION: We concluded dietary Zn intake was negatively associated with childhood eczema. Further studies are needed to explore the roles of dietary antioxidants intake in childhood eczema.

Timing of introduction to solid food, eczema and wheezing in later childhood: a longitudinal cohort study.

BACKGROUND: The timing of introduction to solid food has been associated with eczema and wheezing in childhood. Our aim was to determine whether differences persist within the recommended 4 to 6 month age range. METHODS: A longitudinal cohort study with repeated measures was conducted among children from birth to 10 years of age who were participating in the TARGet Kids! practice based research network in Toronto, Canada. The primary exposure was the timing of introduction to infant cereal as the first solid food. The primary outcome was eczema and the secondary outcome was wheezing collected by parent report using the validated International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Multinomial generalized estimating equations were used and effect modification by family history of asthma and breastfeeding duration were explored. RESULTS: Of the 7843 children included, the mean (standard deviation) age of introduction to infant cereal was 5.7 (1.9) months. There was evidence for family history of asthma and breastfeeding duration to be effect modifiers in the eczema (P = 0.04) and wheezing (P = 0.05) models. Introduction to infant cereal at 4 vs. 6 months of age was associated with higher odds of eczema (OR 1.62; 95% CI: 1.12, 2.35; P = 0.01) among children without a family history of asthma who were not breastfeeding when solid foods were introduced. Introduction to infant cereal at 4 vs. 6 months of age was associated with a higher odds of wheezing (OR 1.31; 95% CI: 1.13, 1.52; P < .001) among children without a family history of asthma who were breastfeeding when solid foods were introduced. There was little evidence of an association among the remaining strata for either outcome. CONCLUSION: The findings of this study support recommendations to introduce solid food around 6 months of age.

Exploration of associations between occupational exposures and current adult eczema.

OBJECTIVES: There is a scarcity of evidence on occupational exposures that may increase eczema in adults. We aimed to investigate potential associations between occupational exposures and eczema in middle-aged adults. METHODS: A lifetime work history calendar was collected from the Tasmanian Longitudinal Health Study participants when they were at age 53. Their work history was collated with the occupational asthma-specific job exposure matrix to define ever-exposure and cumulative exposure unit-years since no eczema job exposure matrix is available. Eczema was determined using the report of flexural rash that was coming and going for at least 6 months in the last 12 months. Skin prick tests were used to further subgroup eczema and atopic eczema (AE) or non-AE (NAE). Logistic and multinomial regression models were used to investigate the associations. RESULTS: Eczema prevalence was 9.1%. Current occupational exposure to animals (adjusted OR, aOR=3.06 (95% CI 1.43 to 6.58)), storage mites (aOR=2.96 (95% CI 1.38 to 6.34)) and endotoxin (aOR=1.95 (95% CI 1.04 to 3.64)) were associated with increased risk of current eczema. Furthermore, increased odds of NAE were associated with current exposure to animals (aOR=5.60 (95% CI 1.45 to 21.7)) and storage mites (aOR=5.63 (95% CI 1.45 to 21.9)). Current exposures to isocyanates (aOR=5.27 (95% CI 1.17 to 23.7)) and acrylates (aOR=8.41 (95% CI 1.60 to 44.3)) were associated with AE. There was no evidence of associations between cumulative exposures and eczema prevalence. Cumulative exposure to metalworking fluids (aOR=1.10 (95% CI 1.01 to 1.22)) was associated with NAE and acrylates (aOR=1.24 (95% CI 1.04 to 1.46)) with AE. CONCLUSIONS: In this exploratory assessment, multiple occupational exposures were associated with current eczema in middle-aged adults. Raising awareness and limiting these exposures during an individual's productive working life will likely have various health benefits, including reducing eczema prevalence.

Maternal dietary patterns during pregnancy and the risk of infantile eczema during the first year of life: a cohort study in northeast China.

BACKGROUND: There are few studies on the relationship between diet during pregnancy and infantile eczema and the conclusions are inconsistent. The aim of the present study was to explore the impact of dietary patterns during pregnancy on infantile eczema. METHODS: A total of 495 mother-child pairs from a prospective cohort in Shenyang, China was recruited. Information on maternal dietary intake during pregnancy was assessed with a validated self-administered food frequency questionnaire. The data of infantile eczema was assessed using a structured questionnaire. Factor analysis to derive dietary patterns. The relationship between the dietary pattern and infantile eczema was examined by the logistic regression analysis. RESULTS: The cumulative incidence of eczema in 6 months and 12 months in northeast China was 45.7% and 57.8%, respectively. Three dietary patterns were identified. There was a tendency for an expose-response relationship between the maternal high-protein dietary pattern during pregnancy and the risk of infantile eczema within 12 months (P for trend = 0.023): the adjusted odds ratio (95% confidence interval) in the Q1, Q2, Q3, Q4 were 1.00 (reference), 1.63 (0.96-2.76), 1.81 (1.06-3.06), and 1.87 (1.09-3.20), respectively. No association between Western and plant-based patterns during pregnancy and infantile eczema within 12 months was found. Infantile eczema within 6 months was not associated with any of the three dietary patterns. CONCLUSION: The maternal high-protein pattern during pregnancy may be a risk factor for infantile eczema during the first year of life.

Prevalence and risk factors for hand eczema among professional hospital cleaners in Denmark: A cross-sectional questionnaire-based study.

BACKGROUND: Professional cleaners are commonly affected by hand eczema (HE) due to wet work and exposure to cleaning products in the work environment. OBJECTIVE: To investigate (1) the prevalence of HE in a group of professional hospital cleaners, (2) the association of HE with various comorbidities and self-reported signs/symptoms of skin lesions and (3) the association of HE with various occupational and personal risk factors in the same population. METHODS: A cross-sectional questionnaire-based study including all cleaners working in three hospitals in Denmark. The questionnaire was composed of 35 questions. Prevalence is reported using proportions with 95% confidence intervals and compared using difference of proportions and Fisher's exact test. RESULTS: A total of 122 out of 180 cleaners (response rate = 68%) participated in this study. The self-reported lifetime prevalence of HE among the cleaners was 30.3%, while the 1-year prevalence was 18.9%. HE was significantly associated with a history of atopic diseases. There was a significant correlation between having HE, and self-reported redness and itch of the hands in the last 12 months, as well as the use of hydrochloric acid ≥4 days/week during the last 12 months. Logistic regression analysis found HE significantly associated with washing hands ≥20 times during a working day and a history of atopic dermatitis. CONCLUSION: Cleaners are at an elevated risk of developing HE. More focus on education/information regarding the prevention and treatment of HE is necessary for the cleaning profession. Self-reported redness and itching of the hands may be a useful prediction of HE in cleaners.

Outcomes of hematopoietic stem cell gene therapy for Wiskott-Aldrich syndrome.

Wiskott-Aldrich syndrome (WAS) is a rare X-linked disorder characterized by combined immunodeficiency, eczema, microthrombocytopenia, autoimmunity, and lymphoid malignancies. Gene therapy (GT) to modify autologous CD34+ cells is an emerging alternative treatment with advantages over standard allogeneic hematopoietic stem cell transplantation for patients who lack well-matched donors, avoiding graft-versus-host-disease. We report the outcomes of a phase 1/2 clinical trial in which 5 patients with severe WAS underwent GT using a self-inactivating lentiviral vector expressing the human WAS complementary DNA under the control of a 1.6-kB fragment of the autologous promoter after busulfan and fludarabine conditioning. All patients were alive and well with sustained multilineage vector gene marking (median follow-up: 7.6 years). Clinical improvement of eczema, infections, and bleeding diathesis was universal. Immune function was consistently improved despite subphysiologic levels of transgenic WAS protein expression. Improvements in platelet count and cytoskeletal function in myeloid cells were most prominent in patients with high vector copy number in the transduced product. Two patients with a history of autoimmunity had flares of autoimmunity after GT, despite similar percentages of WAS protein-expressing cells and gene marking to those without autoimmunity. Patients with flares of autoimmunity demonstrated poor numerical recovery of T cells and regulatory T cells (Tregs), interleukin-10-producing regulatory B cells (Bregs), and transitional B cells. Thus, recovery of the Breg compartment, along with Tregs appears to be protective against development of autoimmunity after GT. These results indicate that clinical and laboratory manifestations of WAS are improved with GT with an acceptable safety profile. This trial is registered at clinicaltrials.gov as #NCT01410825.

Hand eczema in glove-wearing patients.

BACKGROUND: Allergic contact dermatitis to gloves is mostly induced by rubber accelerators. The European baseline series (EBS) appears insufficient to detect glove allergy. Since 2017, it is recommended to use the European rubber series (ERS) and to test the patients' own gloves. OBJECTIVES: To investigate the clinical profile of glove-wearing patients with hand eczema (HE) and to evaluate their sensitisation profile to glove allergens and the value of testing the patients' own gloves. METHODS: We conducted a French multicentre study of patients evaluated for HE between 2018 and 2020 and tested with the EBS, the ERS and their own gloves in patch tests and semi-open (SO) tests. RESULTS: A total of 279 patients were included; 32.6% of patients had positive tests to their own gloves or to glove allergens. Almost 45% of the sensitisations to glove allergens were detected only by the ERS. Among the patients tested both in patch tests and SO tests with their own gloves with positive results, 28% had positive SO tests only. Polyvinylchloride (PVC) gloves were positive in four patients. CONCLUSION: Our series confirms the need to test the ERS. All the patients' gloves must also be tested including PVC gloves. SO tests with gloves are useful as a complement to patch tests.

Association between Polyunsaturated Fatty Acid Intake and Eczema in Children and Adolescents.

INTRODUCTION: Eczema is a common allergic skin condition among children and adolescents, and polyunsaturated fatty acids (PUFAs) are a kind of fatty acid which were reported to be associated with reduced risk of eczema. Previous studies explored different types of PUFAs with various age groups of children and adolescents, and the influence of confounding factors such as medicine use was not considered. In the present study, we aimed to identify the associations between PUFAs and the risk of eczema in children and adolescents. These findings of our study might help better understand the associations between PUFAs and eczema. METHODS: This cross-sectional study collected the data of 2,560 children and adolescents aged 6-19 years from National Health and Nutrition Examination Surveys (NHANES) between 2005 and 2006. Total PUFA, omega-3 (n-3), including octadecatrienoic acid/18:3, octadecatrienoic acid/18:4, eicosapentaenoic acid/20:5, docosapentaenoic acid/22:5, and docosahexaenoic acid/22:6, omega-6 (n-6), including octadecatrienoic acid/18:2 and eicosatetraenoic acid/20:4, total n-3 intake, total n-6 intake, and n-3/n-6 were main variables in this study. Univariate logistic regression was applied for identifying potential confounders for eczema. Univariate and multivariate logistic regression analysis were conducted to explore the associations between PUFAs and eczema. Subgroup analysis was performed on subjects with different ages, and patients complicated with other allergic diseases, allergy, and medicine use or not. RESULTS: In total, there were 252 (9.8%) subjects who had eczema. After adjusting for confounding factors including age, race, poverty to income ratio (PIR), medicine use, hay fever, sinus infection, body mass index (BMI), serum total immunoglobulin E (IgE) antibody, and IgE, we observed that eicosatetraenoic acid/20:4 (OR = 0.17, 95% CI: 0.04-0.68) and total n-3 (OR = 0.88, 95% CI: 0.77-0.99) were linked with decreased risk of eczema in children and adolescents. Eicosatetraenoic acid/20:4 was correlated with decreased risk of eczema in participants without hay fever (OR = 0.82, 95% CI: 0.70-0.97) and medicine use (OR = 0.80, 95% CI: 0.68-0.94) or with allergy (OR = 0.75, 95% CI: 0.59-0.94). Total n-3 intake was associated with a reduced risk of eczema with the adjusted OR of 0.84, 95% CI: 0.72-0.98) in participants without hay fever. In those without sinus infection, octadecatrienoic acid/18:4 was linked with decreased risk of eczema (OR = 0.83, 95% CI: 0.69-0.99). CONCLUSION: N-3 and eicosatetraenoic acid/20:4 might be associated with the risk of eczema in children and adolescents.

Atopic Dermatitis (Eczema).

This JAMA Patient Page describes atopic dermatitis (eczema) and its symptoms and treatment options.

Maternal affective and stress-related factors during pregnancy affect the occurrence of childhood allergic diseases: A Shanghai MCPC study.

OBJECTIVE: To investigate the association between exposures to maternal affective and stress-related factors during pregnancy and allergies in children from birth to 2 years of age. METHODS: We enrolled a total of 4178 children from the Shanghai Maternal-Child Pairs Cohort and measured maternal stress, anxiety, and depression during pregnancy by applying the Life Events Scale for Pregnant Women, Self-Rating Anxiety Scale, and the Center for Epidemiologic Studies-Depression Scale, respectively. Children's allergies were assessed by community physicians at 2, 6, 12, and 24 months, respectively; these included eczema, atopic dermatitis, food allergy, wheezing, asthma, and atopic rhinitis. We applied a latent class analysis (LCA) to these factors and analyzed the impacts of maternal affective and stress-related factors on childhood allergies by exploiting multivariate logistic regression. RESULTS: Three distinct classes of children were revealed by LCA: healthy (79.8%), transient allergy (15.2%), and persistent allergy (4.9%). High maternal stress in both early and late pregnancy was associated with an increased risk of infant eczema at 2 months (aOR = 1.30, 95% CI = 1.01-1.67; aOR = 1.64, 95% CI = 1.14-2.36). Moreover, high maternal stress in late pregnancy was also associated with food allergy at 6 months, rhinitis at 2 years of age, and persistent allergy (aOR = 3.22, 95% CI = 1.27-8.12; aOR = 1.78, 95% CI = 1.01-3.15; and aOR = 1.93, 95% CI = 1.10-3.40). CONCLUSIONS: The associations of maternal affective and stress-related factors during pregnancy with childhood allergies may vary by type and disease onset. We postulate that maternal stress in late pregnancy may exert a sustained negative effect on early childhood allergic diseases.

Endotoxin concentration and persistent eczema in early childhood.

Although endotoxin concentration in the environment is negatively associated with atopic dermatitis (AD) onset in early childhood, the association between endotoxin concentration in the environment and eczema resolution in children with preexisting eczema is unclear. The aim of this study was to evaluate the association between endotoxin concentration in house dust and eczema persistence in young children. The authors used data from children participating in JECS (Japan Environment and Children's Study). In children who had AD or AD-like lesions at the age of 1 year, the authors investigated the association between the prevalence of eczema at the age of 3 years and endotoxin concentration (categorized by quartiles) in the dust on children's mattresses at the ages of 1.5 and 3 years. This study included 605 children. Eczema was significantly less prevalent among children whose mattresses were in the second and third quartiles of endotoxin concentration when they were 18 months old than among children whose mattresses were in the first quartile (adjusted odds ratio, 0.57 [95% confidence interval, 0.35-0.93] and adjusted odds ratio, 0.49 [95% confidence interval, 0.29-0.83], respectively). Moreover, of the children with eczema at age 3 years, those whose mattresses had endotoxin concentrations in the first quartile had significantly worse sleep disturbance caused by itchy rash (>1 time per week) than did those whose mattresses were in the third and fourth quartiles (20.0% vs 3.3% and 3.7%, both p values < 0.01). The findings indicate that low endotoxin exposure is associated with a higher prevalence of persistent eczema during early childhood.

Parental occupational exposures prior to conception and offspring wheeze and eczema during first year of life.

PURPOSE: Parental exposures prior to conception might influence asthma and allergy risk in offspring. As occupational exposures are established risk factors for asthma and allergies, we investigated if parental occupational exposures prior to conception cause wheeze and eczema in offspring during the first year of life. METHODS: We analysed data of 436 families from an offspring cohort based on a follow-up study of German participants of the International Study of Asthma and Allergies in Childhood (ISAAC). Offspring cohort data was collected between 2009 and 2019. Occupational exposures were based on participants' work histories and measured by a Job-Exposure-Matrix. We used Bayesian logistic regression models for analysis. Inference and confounder selection were based on directed acyclic graphs. RESULTS: In mothers, for both allergic and irritative occupational exposures prior to conception suggestive effects on offspring eczema during the first year of life were found (allergens: odds ratio (OR) 1.22, 95% compatibility interval (CI) 0.92-1.57; irritants: OR 1.36, 95% CI 0.99-1.77), while no relation with wheeze was suggested. CONCLUSIONS: Our results suggest that reduction of asthma-related occupational exposures might not only reduce the burden of disease for occupationally induced or aggravated asthma and allergies in employees but also in their children.

Aetiology of occupational hand eczema in hairdressers: Tackling the complexity of exposure combinations to identify patterns associated with increased risk of hand eczema.

INTRODUCTION: Hairdressers are exposed to wet work and manifold allergens at work, rendering exposure complex and the aetiology of occupational hand eczema (OHE) often multifactorial in this occupational group. OBJECTIVES: To identify exposure patterns associated with increased risk of hand eczema in hairdressers. METHODS: All hairdressers graduating from 2004 to 2007 and 2015 to 2018 received a questionnaire in 2009 and 2020, respectively. Current exposures (with or without regular glove use) and OHE were self-reported, and their association examined. Patterns of exposure were identified by latent class analysis (LCA). RESULTS: A total response of 39.9% (668/1675) was obtained. Six exposure profiles (#1-6) were identified by LCA across 11 tasks performed with or without gloves as well as deep conditioning, that is, 23 task items. Compared to profile #1 with the lowest OHE risk (reference) an increased risk of current OHE were seen in profile #4 [adjusted odds ratio [aOR] 6.5, 95% confidence interval [CI] 1.5-44.8 and #6 (aOR 39.4, 95%CI 6.1-362.8)] in logistic regression analysis. Profile #1 and #6 had performed the same tasks, but in profile #6 regular glove use was performed in 9.1% (1/ 11) of tasks compared to 72.7% (8/11) of tasks in profile #1 (p = 0.002). CONCLUSION: Although occupational exposures in hairdressing are complex, meaningful patterns associated with a wide range of OHE risk can be identified by LCA. The increase of OHE risk seems predominantly to be due to poor compliance with protective gloves. LCA could be applied to further fields of complex (skin) exposures.