Sensitisation to staphylococcal enterotoxins and asthma severity: a longitudinal study in the EGEA cohort

International audienc

Is immunoglobulin E to Staphylococcus aureus enterotoxins associated with asthma at 20 years?

Background: In adults, subjects sensitized to Staphylococcus aureus enterotoxins (SE) seem to have an increased risk of asthma, whereas this association is less clear in childhood and adolescence. The primary aim of the present analysis was to examine the association between sensitization to SE and asthma at the age of 20years. Methods: The German Multicentre Allergy Study recruited 1314 healthy newborns in 1990. We analyzed data from 61 asthmatics (based on at least two criteria: physician diagnosed asthma ever, wheezing in the last 12months, asthma medication in the last 12months) and 122 healthy study participants at age 20. In serum, specific Immunoglobulin E (IgE) to SE and common aeroallergens were measured. The association between asthma at age 20 and sensitization to SE was estimated by logistic regression models considering allergic, socio-demographic, and lifestyle factors as potential confounders. Results: Fifty-five percent of the included participants were female. At age 20, subjects sensitized to SE were more likely to have asthma than not-sensitized subjects: raw odds ratio (OR) 2.5, 95%-confidence interval (95%CI) [1.3-4.7]; adjusted OR 1.6, 95%CI [0.8-3.4]. Conclusion: Asthmatics at age 20 were more often sensitized to SE compared to controls. Our study may indicate a moderate relationship between SE-sensitization and asthma; however, this association attenuated after adjusting for potential confounders and was no longer statistically significant. Longitudinal investigations with SE-IgE measurements at different time points in larger samples are needed to explore the temporal manner of this relationship

Is immunoglobulin E to Staphylococcus aureus enterotoxins associated with asthma at 20 years of age?

Background: In adults, subjects sensitized to Staphylococcus aureus enterotoxins (SE) seem to have an increased risk of asthma, whereas this association is less clear in childhood and adolescence. The primary aim of the present analysis was to examine the association between sensitization to SE and asthma at the age of 20years. Methods: The German Multicentre Allergy Study recruited 1314 healthy newborns in 1990. We analyzed data from 61 asthmatics (based on at least two criteria: physician diagnosed asthma ever, wheezing in the last 12months, asthma medication in the last 12months) and 122 healthy study participants at age 20. In serum, specific Immunoglobulin E (IgE) to SE and common aeroallergens were measured. The association between asthma at age 20 and sensitization to SE was estimated by logistic regression models considering allergic, socio-demographic, and lifestyle factors as potential confounders. Results: Fifty-five percent of the included participants were female. At age 20, subjects sensitized to SE were more likely to have asthma than not-sensitized subjects: raw odds ratio (OR) 2.5, 95%-confidence interval (95%CI) [1.3-4.7]; adjusted OR 1.6, 95%CI [0.8-3.4]. Conclusion: Asthmatics at age 20 were more often sensitized to SE compared to controls. Our study may indicate a moderate relationship between SE-sensitization and asthma; however, this association attenuated after adjusting for potential confounders and was no longer statistically significant. Longitudinal investigations with SE-IgE measurements at different time points in larger samples are needed to explore the temporal manner of this relationship

Contribution of repeated infections in asthma persistence from preschool to school age:Design and characteristics of the PreDicta cohort

Background: The PreDicta cohort was designed to prospectively evaluate wheeze/asthma persistence in preschoolers in association with viral/microbial exposures and immunological responses. We present the cohort design and demographic/disease characteristics and evaluate unsupervised and predefined phenotypic subgroups at inclusion. Methods: PreDicta is a 2-year prospective study conducted in five European regions, including children 4-6years with a diagnosis of asthma as cases and healthy age-matched controls. At baseline, detailed information on demographics, asthma and allergy-related disease activity, exposures, and lifestyle were recorded. Lung function, airway inflammation, and immune responses were also assessed. Power analysis confirmed that the cohort is adequate to answer the initial hypothesis. Results: A total of 167 asthmatic children (102 males) and 66 healthy controls (30 males) were included. Groups were homogeneous in respect to most baseline characteristics, with the exception of male gender in cases (61%) and exposure to tobacco smoke. Comorbidities and number and duration of infections were significantly higher in asthmatics than controls. 55.7% of asthmatic children had at least one positive skin prick test to aeroallergens (controls: 33.3%, P=.002). Spirometric and exhaled nitric oxide values were within normal limits; only baseline FEV0.5 and FEV1 reversibility values were significantly different between groups. Viral infections were the most common triggers (89.2%) independent of severity, control, or atopy; however, overlapping phenotypes were also common. Severity and control clustered together in an unsupervised analysis, separating moderate from mild disease. Conclusions: The PreDicta cohort presented no differences in non-asthma related measures; however, it is well balanced regarding key phenotypic characteristics representative of preschool asthma

Staphylococcal enterotoxin IgE sensitization in late-onset severe eosinophilic asthma in the elderly

Background: Asthma in the elderly (aged 65years old) is a significant concern with high morbidity, but the pathophysiology remains unclear particularly in late-onset asthma. Recent studies suggest staphylococcal enterotoxin IgE (SE-IgE) sensitization to be a risk factor for asthma in general populations; however, the associations have not been examined in late-onset elderly asthma. Objective: We aimed to examine the associations of SE-IgE sensitization with late-onset asthma in the elderly, using a database of elderly asthma cohort study. Methods: A total of 249 elderly patients with asthma and 98 controls were analysed. At baseline, patients were assessed for demographics, atopy, induced sputum profiles and comorbidities including chronic rhinosinusitis (CRS). Serum total IgE and SE-IgE levels were measured. Asthma severity was assessed on the basis of asthma outcomes during a 12-month follow-up period. Results: At baseline, serum SE-IgE concentrations were significantly higher in patients with asthma than in controls [median 0.16 (interquartile range 0.04-0.53) vs. 0.10 (0.01-0.19), P<0.001]. Elderly asthma patients with high SE-IgE levels had specific characteristics of having more severe asthma, sputum eosinophilia and CRS, compared to those with lower SE-IgE levels. In multivariate logistic regression analyses, the associations between serum SE-IgE concentrations and severe asthma were significant, independently of covariables [SE-IgE-high (0.35kU/L) vs. negative (<0.10kU/L) group: odds ratio 7.47, 95% confidence interval 1.86-30.03, P=0.005]. Multiple correspondence analyses also showed that high serum SE-IgE level had close relationships with severe asthma, CRS and sputum eosinophilia together. Conclusions and Clinical Relevance: This is the first report on the significant associations of SE-IgE sensitization with late-onset asthma in the elderly, particularly severe eosinophilic asthma with CRS comorbidity. Our findings indicate a potential implication of SE in the high morbidity burden of elderly asthma and suggest clues to the pathogenesis of severe late-onset eosinophilic asthma in the elderly