Distribution of inflammatory phenotypes among patients with asthma in Jilin Province, China: a cross-sectional study

Abstract

Background The inflammatory phenotypes of asthma predict the treatment response and prognosis. The phenotype distributions differ depending on the geographical region. This study aimed to assess the distribution of different inflammatory phenotypes among asthma patients in Jilin Province, China. Methods A total of 255 patients with asthma were recruited from Jilin Province, China for this cross-sectional study. Each patient underwent sputum induction following clinical assessment and peripheral blood collection. Inflammatory phenotypes were classified according to the inflammatory cell counts in the sputum. Results Paucigranulocytic asthma (PGA) was the most common inflammatory phenotype (52.2%), followed by eosinophilic asthma (EA, 38.3%), mixed granulocytic asthma (MGA, 5.2%), and neutrophilic asthma (NA, 4.3%). NA was more common among patients over 45 years old and those who were treated with higher doses of inhaled corticosteroids (ICS), but was less common following antibiotics treatment (p < 0.05). The proportion of patients with EA decreased as the ICS treatment dose and time increased (p = 0.038). Patients with uncontrolled asthma had higher numbers of sputum eosinophils and neutrophils (p < 0.05). Patients with severe asthma had a higher percentage of sputum neutrophils (p < 0.05). A greater proportion of patients with NA had severe asthma (60%) compared to those with EA (18.2%) (p = 0.016). Conclusions The most common asthma inflammatory cell phenotype in Jilin Province, China is PGA, followed by EA, MGA, and NA. The low prevalence of NA in Jilin Province compared to other countries and also other regions in China might be due to excessive antibiotic use and irregular ICS treatment in this region.

Analysis of Patients with Asthma and Mixed Granulocytic Inflammatory Pattern in Sputum

“…ICS treatment significantly affects blood and sputum eosinophils [20]; however, in spite of most of our patients being treated with ICS, more than 59% of the subjects still had an eosinophilic inflammation (eosinophilic + mixed granulocytic patterns). As a consequence, in our study, the frequency of paucigranulocytic subjects was lower than in other studies [21][22][23]. Furthermore, since more than 74% of subjects with a paucigranulocytic pattern were ICS treated and they more frequently had early onset asthma, it is plausible that they are the ones in whom treatment has been efficacious at least from the inflammatory point of view.…”

Inter-relationships among neutrophilic inflammation, air trapping and future exacerbation in COPD: an analysis of ECOPD study

“…We divided the sputum neutrophil proportions by its median (86.2%) into high and low levels before our analysis. Notably, sputum neutrophil cut-offs are higher than the cut-offs (86.2% vs 61.0%) in previous studies 29 30. The 61.0% cut-off of sputum neutrophil proportion was derived from the asthma population but not the COPD population in previous studies.…”

“…Notably, sputum neutrophil cut-offs are higher than the cut-offs (86.2% vs 61.0%) in previous studies. 29 30 The 61.0% cut-off of sputum neutrophil proportion was derived from the asthma population but not the COPD population in previous studies. Neutrophils are prominent in COPD, but less prominent in asthma.…”

Screening for cytological changes associated with inhaled polluted materials in Khartoum industrial area

“…Sputum cytology results concerning inflammatory cells might be applied as a diagnostic tool to test lung function (Shi et al, 2021). In the current study, the total number of WBCs was relatively elevated in most individuals with cytological changes.…”