D1.161 - Clinical-epidemiological profile of pediatric difficult-to-control asthma in a tertiary referral center in Brazil

Pediatric Difficult-to-Control Asthma (DCA) imposes significant clinical challenges, yet data on this population in high-complexity Brazilian centers are scarce. This study aimed to analyze the clinical-epidemiological profile, phenotypes, control levels, and therapeutic approach of pediatric patients with DCA in a tertiary hospital.

This is an observational, descriptive, and retrospective study that included patients treated at a specialized outpatient clinic between June 2022 and May 2025. Demographic data, type 2 inflammatory biomarkers, asthma control scores (ACT/C-ACT), and lung function (FEV1) were collected. Spearman correlation and Mann-Whitney tests were used for statistical analysis.

The sample included 73 patients. The mean age was 10.4 years, with a predominance of males (65.8%) and severe asthma (68.5%). A marked predominance of the T2-high profile was observed, distributed among mixed allergic-eosinophilic (71%), purely eosinophilic (12%), and allergic (10%) phenotypes. Allergic rhinitis was the most frequent comorbidity, affecting 96% of patients. A positive correlation was found between the number of sensitizations in skin prick tests and serum IgE levels (rho = 0.494; p<0.001), with no statistical association between clinical severity and biomarkers. There was a dissociation between perceived control (ACT) and objective lung function (FEV1) (rho = 0.239; p=0.221). Biologics were used in 15.1% of patients.

The evaluated pediatric population is characterized mainly by severe asthma, male sex, and strong expression of the T2-high phenotype, where polysensitization correlates with IgE magnitude. The discrepancy between reported symptoms and lung function suggests poor disease perception, reiterating the need for multimodal monitoring with biomarkers and spirometry to optimize management.