The Genomics and Metagenomics of Asthma Severity (GEMAS) Study: Rationale and Design

Abstract

Asthma exacerbations are a major contributor to the global disease burden, but no significant predictive biomarkers are known. The Genomics and Metagenomics of Asthma Severity (GEMAS) study aims to assess the role of genomics and the microbiome in severe asthma exacerbations. Here, we present the design of GEMAS and the characteristics of patients recruited from March 2018 to March 2020. Different biological samples and demographic and clinical variables were collected from asthma patients recruited by allergy and pulmonary medicine units in several hospitals from Spain. Cases and controls were defined by the presence/absence of severe asthma exacerbations in the past year (oral corticosteroid use, emergency room visits, and/or asthma-related hospitalizations). A total of 137 cases and 120 controls were recruited. After stratifying by recruitment location (i.e., Canary Islands and Basque Country), cases and controls did not differ for most demographic and clinical variables (p > 0.05). However, cases showed a higher proportion of characteristics inherent to asthma exacerbations (impaired lung function, severe disease, uncontrolled asthma, gastroesophageal reflux, and use of asthma medications) compared to controls (p < 0.05). Similar results were found after stratification by recruitment unit. Thereby, asthma patients enrolled in GEMAS are balanced for potential confounders and have clinical characteristics that support the phenotype definition. GEMAS will improve the knowledge of potential biomarkers of asthma exacerbations.

Human genetics influences microbiome composition involved in asthma exacerbations despite inhaled corticosteroid treatment

“…A total of 257 saliva, 232 pharyngeal, and 229 nasal samples from European individuals with asthma from the Genomics and Metagenomics of Asthma Severity (GEMAS) study were analyzed in the discovery phase. 9 Their main demographic and clinical characteristics are summarized in Table I . Briefly, subjects had a median age of 39.0 years (interquartile range, 18.0-59.0 years) and 61.5% were female.…”

The upper-airway microbiome as a biomarker of asthma exacerbations despite inhaled corticosteroid treatment

“…A full description of the study design, eligibility criteria, and characteristics of enrolled subjects is reported elsewhere. 13 Briefly, European patients aged between 8 and 85 years with a diagnosis of asthma based on the Global Initiative for Asthma (GINA) 2020 guidelines 3 were recruited in several allergy and respiratory medicine hospital units in Spain. GEMAS was approved by the ethics committees of participant centers (approval nos.…”

Severe Asthma and Biological Therapies: Now and the Future

“…Within the Genomics and Metagenomics of Asthma Severity (GEMAS) project [ 189 ], which included 250 asthmatic patients treated with ICS, our group studied the association between the salivary, pharyngeal, and nasal microbiome with asthma exacerbations, wherein it was observed that, in nasal and saliva samples, those who had presented moderate or severe exacerbations (use of OCS and/or hospital admission) had less bacterial diversity than those who did not present exacerbations [ 190 ]. Exacerbations accounted for 8% to 9% of the interindividual variation in the salivary and nasal microbiomes, respectively.…”