10/6/03 Effect of inhaled fluticasone with and without added salmeterol on airway inflammationSummaryA number of studies have shown that asthma symptomatology can be controlled as well by adding inhaled salmeterol (SALM), a long-acting beta agonist, to low dosage inhaled corticosteroid (ICS) therapy as by doubling the does of the ICS. However, concerns have been raised that airway inflammation may not be as well controlled with the low dosage ICS plus SALM as would occur with higher dose ICS as monotherapy. Wallin et al of the Univ. Hospital in Umea, Sweden investigated the patterns of bronchial inflammation during therapy of 56 adult asthmatics (previously not well controlled on low dose ICS alone). These individuals were then subsequently treated with either a) the ICS agent fluticasone propionate (FP), 500 mcg bid (called FP 1000); b) FP 200 mcg bid plus SALM 50 mcg bid (called FP 400+ SALM) or c) FP 200 mcg bid alone (called FP 400). After the 3 month treatment period, there was greater improvement in both the FEV-1 and PEFR in the FP 400+SALM group than in the other 2 groups. Based on findings in bronchial biopsies, bronchoalveolar lavage, or bronchial washings obtained at the end of the treatment period, there was no significant difference in the frequencies of submucosal mast cells or eosinophils in the airways of the FP 400+SALM and the F1 1000 groups. The authors concluded that the addition of SALM to lower dose FP confers clinical benefit without allowing any more inflammation than seen with high dose FP (1000 mcg/day). Reference J Allergy Clin Immunol 2003; 112; 72-8 Editor’s Comments These findings are encouraging in perhaps dispelling the concern that bronchial inflammation may actually increase, leading to increased bronchial reactivity and possible deleterious airway remodeling, when the addition of SALM allows use of lower dose ICS treatment. This combination of low dose ICS plus SALM has real potential advantages over high dose ICS since a number of adverse systemic effects of ICS therapy are ICS dose- dependent (the more that is used, the more that is absorbed systemically from the lungs). However, questions can be raised whether the frequency of mast cells and eosinophils in the airway mucosa are reliable measure of asthma severity. Some studies have shown that clinical severity of asthma appears to correlate with mast cells frequency in the airways. However, the pathogenic role of airway eosinophilia is less clear than was considered several years ago. More information is needed.
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