Relation between inflammation and symptoms in asthma

Abstract

Asthma symptoms are the main reason for healthcare utilization and are a fundamental parameter for the evaluation of asthma control. Currently, asthma is defined as a chronic inflammatory disease. A French expert group studied the association between inflammation and asthma symptoms by carrying out a critical review of the international literature. Uncontrolled asthmatics have an increased number of polynuclear eosinophils in the induced sputum and an increased production of exhaled NO. Control by anti‐inflammatory treatment is accompanied by a reduction in bronchial eosinophilia and exhaled NO. Asthma symptoms are the result of complex mechanisms and many factors modify their perception. Experimental data suggest that there is a relationship between the perception of symptoms and eosinophilic inflammation and that inhaled corticoid therapy improves this perception. Although they are still not applicable in routine practice, follow‐up strategies based on the evaluation of inflammation are thought to be more effective in reducing exacerbations than those usually recommended based on symptoms and sequential analysis of respiratory function. Inhaled corticosteroid therapy is the reference disease‐modifying therapy for persistent asthma. Recent studies demonstrated that adjustment of anti‐inflammatory treatment based on symptoms is an effective strategy to prevent exacerbations and reduce the total number of doses of inhaled corticosteroids.

Association of Asthma Symptoms and Exacerbation with Inflammatory Biomarkers

“…Airway inflammation in asthmatics is usually monitoring with exhaled NO and certain number of studies indicates a relation between FENO and asthma symptoms or symptoms score [9]. In our study, FENO weakly positively correlated with heavy breathing.…”

“…Other studies have evaluated the general effect of a treatment or therapeutic strategy. A few studies have investigated tissue inflammation with bronchial biopsies, and more recently, exhaled breath condensates and their relation to symptoms [9].…”

Serum eosinophilic cationic protein and high sensitive C-reactive protein as alternative parameters for differentiation of severity stages and monitoring control in bronchial asthma patients

“…These cytokines are increased due to asthmatic inflammation [16,17]. Severity of asthma correlates positively with asthmatic inflammation [18].…”

Asthma control, quality of life and successful sputum induction

“…It is well known that ICS decrease airway eosinophilia, which usually leads to better asthma control, while in contrast asthma exacerbation leads to a rise in eosinophil level. Clinical assessment of asthmatics using induced sputum as a method evaluating airway inflammation is thought to be more effective in reducing exacerbations than strategies usually recommended based on symptoms and sequential analysis of respiratory function [13]. The observation that successful sputum induction may be expected in patients with better asthma control and better quality of life may encourage its more frequent use in clinical assessments of such asthmatics to prevent undertreatment with ICS, which therefore may prevent disease exacerbation.…”