Inhaled corticosteroids and growth of airway function in asthmatic children

Abstract

Airway inflammation and remodelling play an important role in the pathophysiology of asthma. Remodelling may affect childhood lung function, and this process may be reversed by anti-inflammatory treatment. The current study assessed longitudinally whether asthma affects growth of airway function relative to airspaces, and if so whether this is redressed by inhaled corticosteroids (ICS).Every 4 months for up to 3 yrs, lung function was assessed in 54 asthmatic children (initial age 7-16 yrs), who inhaled 0.2 mg salbutamol t.i.d. and 0.2 mg budesonide t.i.d.Measurements were carried out before and after maximal bronchodilation. Airway growth was assessed from the change of forced expiratory volume in one second and of maximal expiratory flows (at 60% and 40% of total lung capacity (TLC) remaining in the lung) relative to TLC, as measures of more central, intermediate and more peripheral airways. Growth patterns were compared with the longitudinal findings in 376 healthy children.Airway patency after maximal bronchodilation in patients on BAzPL remained reduced compared to healthy subjects, whereas in patients on BAzICS a marked improvement was observed to subnormal. No differences between patients and controls could be demonstrated for growth patterns of central and intermediate airway function. Compliance with BAzICS was 75% of the prescribed dose, resulting in significant, sustained improvement of symptoms and postbronchodilator calibre of central and intermediate airways to subnormal within 2 months, but postbronchodilator small airway patency remained reduced, though improved compared to patients on BAzPL.Anti-inflammatory treatment of asthmatic children is associated with normal functional development of central and intermediate airways. The persistently reduced postbronchodilator patency of peripheral airways may reflect remodelling, or insufficient anti-inflammatory treatment.

Long-term asthma treatment guided by airway hyperresponsiveness in children: a randomised controlled trial

“…The present authors speculate that this may be related to initial asthma severity. MERKUS et al [28] examined the effect of ICS on the progression of FEV1 in children aged .3 yrs, and showed preservation of lung function compared with placebo. In children receiving placebo, pre-and postbronchodilator values ran largely in parallel, whereas a ceiling effect towards a submaximal level was seen with ICS.…”

Monitoring asthma in childhood

“…Asthma is clearly associated with reduced lung function, as well as a more rapid decline in lung function compared to healthy individuals, although impairments in lung function appear more modest among children than adults [8][9][10][11]. But even in children and adolescents with mild-to-moderate asthma with adequate anti-inflammatory treatment, lung function following maximal bronchodilation is still somewhat reduced compared to healthy children, suggesting that airway remodelling affects lung function even in well-controlled paediatric asthma [27]. In a few birth cohorts, reduced lung function has been found to precede asthma in some, but not all children with asthma [28][29][30].…”

Standing on shoulders

“…Obviously, ''classical'' and anatomical studies have been regularly used to confirm anatomical and pathological concepts, using lung function data to assess growth of lungs and airways in healthy children [3,4], children with asthma [5] or preterm infants [6]. However, the study by CHANG et al…”

“…Obviously, ''classical'' and anatomical studies have been regularly used to confirm anatomical and pathological concepts, using lung function data to assess growth of lungs and airways in healthy children [3,4], children with asthma [5] or preterm infants [6]. However, the study by CHANG et al [1] is far more advanced because it introduces new applications of novel infant lung function techniques and incorporates these with classic physiological concepts [2], while combining them with advanced subtyping of progenitor cells.…”