Pulmonary Function in Adults with Severe Eosinophilic Asthma Using Biologicals:A Case-Control Study.

Abstract

The era of biologics has revolutionized the treatment of severe eosinophilic asthma (SEA). Although biologics appear to control SEA, pulmonary function is still poorly assessed with effective techniques. This study aimed to compare pulmonary function between adults living with severe asthma (alwSEA) with and without the use of biologics through a comprehensive approach to measuring pulmonary function, including assessments of pulmonary mechanics, static lung volumes, and small airways.

Methodology: This is a cross-sectional study in which 15 alwSEA using biologics (biological group-BG) and 17 alwSEA using conventional therapy (control group-CG) were evaluated. These individuals underwent spirometry, body plethysmography, and respiratory oscillometry. In addition, they underwent the Asthma Control Test and the Asthma Quality of Life Questionnaire.

Results: The sample was predominantly female, with 14 women (93.3%) in the BG and 16 (94.1%) in the CG. The groups differed significantly in age, with the BG being younger than the CG [52 (47-61) vs. 60 (54-66) years, p=0.045]. The BG presented significantly higher values ​​of forced expiratory volume in the first second [1.77 (1.45-1.91) vs. 1.27 (1.18-1.47) L, p=0.005]. The CG presented a higher residual volume to total lung capacity ratio [141 (128-157) vs. 108 (89-117) % predicted, p<0.001]. Respiratory system resistance at 20 Hz was higher in the CG [170 (137-216.5) vs. 131.5 (110.8-179.2) % predicted, p=0.038].

Conclusions: In alwSEA, biologics appear to improve not only volumes and flows, but also air trapping. Furthermore, biologics appear to act on central airway resistance.