Peculiarities of response to basic anti-inflammatory therapy of schoolchildren with alternative inflammatory phenotypes of bronchial asthma

Abstract

Purpose — to evaluate the effectiveness of long-term anti-inflammatory therapy with inhaled glucocorticosteroids in children with alternative inflammatory phenotypes of bronchial asthma (BA) for the development of individualized control treatment.

Materials and methods. A comprehensive survey of 94 school-age children with BA was conducted. According to the results of cytological examination of sputum, 2 clinical observation groups were formed. The first group of patients was formed by 38 patients with non3eosinophilic (neutrophilic) nature of the inflammatory process of the bronchi (mean age — 11.1±2.9 years, the proportion of boys — 52.6±8.1%), and the second group — 56 children with eosinophilic type of airway inflammation (3% or more of eosinophilic granulocytes in sputum), ie eosinophilic asthma phenotype (mean age — 12.2±3.2 (P>0.05) years, the proportion of boys — 67.9±6.2%, P>0.05). According to the main characteristics of the observation group could be compared.

All patients underwent a comprehensive clinical and paraclinical (spirographic) examination. Scoring control of BA symptoms was performed using a questionnaire at the beginning and at the end of the course of anti-inflammatory basic therapy. The questionnaire included the clinical signs of BA reflected in the scores, which were evaluated by patients and their parents, as well as the scale of instrumental studies according to the spirographic examination of patients.

Results. The paper shows that the best effect of long-term courses of basic therapy with inhaled glucocorticosteroids (ICS) was observed in patients with eosinophilic airway inflammation. Thus, the share of patients with a relatively satisfactory level of clinical control of the disease and with close to normal spirographic indicators was in group II: before the course of treatment with inhaled corticosteroids 25.0% and 31.9%, and after treatment — 81.3% (P<0,01) and 69.0% (P<0.01), respectively. Thus, an increase of 69.3% in relative risk (IRR) and 56.3% in absolute risk (IAR) of BA control reflected a pronounced control effect of inhaled corticosteroids in the eosinophilic nature of airway inflammation. The minimum number of patients needed to treat (NNT) in order to obtain at least one positive result was 2. At the same time, in patients with neutrophilic inflammatory process, the proportion of patients with a relatively satisfactory level of clinical and paraclinical (according to spirography) disease control was: before the appointment of ICS — 30.8% and 30.8%, and after treatment — 50% (PFisher's exact test>0.05) and 76.9% (PFisher's exact test<0.01), respectively. This persistence of clinical manifestations of the disease indicated an insufficient level of control of non3eosinophilic BA in the treatment of inhaled corticosteroids and questioned the feasibility of monotherapy with this group of neutrophilic bronchitis. The insufficient effect of anti3inflammatory therapy with inhaled corticosteroids was evidenced by the fact that IRR of satisfactory level of clinical control was 38.4%, IAR — 19.2%, and NNT — 6 patients.

Conclusions. In patients with the eosinophilic phenotype of BA, the use of long courses of inhaled glucocorticosteroids led to an increased chance of achieving disease control, while the chances of improving of the pulmonary function tests were also observed in the neutrophilic phenotype of the disease.

The research was carried out in accordance with the principles of the Helsinki declaration. The study protocol was approved by the Local ethics committee of the participating institution. The informed consent of the patient was obtained for conducting the studies.

No conflict of interest was declared by the authors.