Airway inflammation in patients with symptoms suggesting asthma but with normal lung function

Abstract

The hypothesis that eosinophilic airway inflammation is present in many patients presenting with respiratory symptoms suggestive of asthma but with normal lung function was tested. Thirty-six consecutive patients presenting with these features were studied. Twenty-five asthmatics and 43 healthy volunteers served as control groups. Signs of eosinophilic inflammation in blood and induced sputum were studied. Patients with respiratory symptoms were single-blindly treated with inhaled beclomethasone dipropionate (BDP), 800 microg daily, or placebo for 3 months, and re-examined at 3 months and 1 yr. Patients with respiratory symptoms had higher numbers of blood and sputum eosinophils than healthy persons (p<0.0001), but the degree of eosinophilic inflammation was less pronounced than in asthmatics (p<0.01). Three-month's treatment with BDP significantly reduced total symptom score (p<0.001), cough score (p<0.0001), and the number of blood eosinophils (p<0.01). For cough alone, the improvement was significant compared with placebo (p<0.05). The patients were followed-up for 1 yr, and 17 (55%) still had symptoms but retained normal lung function. Four (13%) patients had developed asthma and another 10 (32%) had become free of symptoms. Using lung function measurements and induced sputum analyses, a group of patients with symptoms suggestive of asthma and signs of eosinophilic airway inflammation but without enough airflow variability to be diagnosed as asthmatics were detected. They seemed to respond favourably to inhaled beclomethasone dipropionate treatment.

Treatment with inhaled steroids in patients with symptoms suggestive of asthma but with normal lung function

“…This demonstrates that treatment with an inhaled corticosteroid benefited the patients, even if they did not show a reversible airway obstruction at baseline or a marked PEF variability during the run-in period (mild hidden obstruction). The efficacy appears to be comparable to that shown in a 3-month study with beclomethasone dipropionate in a similar but smaller study population [13].…”

“…In a small pilot-type study, treatment with inhaled beclomethasone dipropionate for 3 months significantly reduced symptoms in patients in whom asthma was suspected, but lung function measurements did not confirm the diagnosis [13]. The present study evaluated whether these previous results could be repeated in a larger setting when patients were recruited on a multicentre basis.…”

“…Often, these patients have recurrent cough as their main symptom. An eosinophilic airway inflammation is a common finding [5,[13][14][15], although most patients are left without a confirmed diagnosis and the delay in diagnosing asthma may be considerable [16]. A small survey in Finland showed a mean delay from the initial symptoms suggestive of asthma to a physician-made diagnosis of 19 months in children and 64 months in adults [11,16].…”

Clinical outcome of eosinophilic airway inflammation in chronic airway diseases including nonasthmatic eosinophilic bronchitis

“…Our study showed that NAEB patients did experience acute exacerbations during the follow-up period. As mentioned previously, NAEB patients could have respiratory symptoms other than cough, such as chest tightness with wheezing, shortness of breath, and sputum production [8][9][10] . Treatment with systemic corticosteroids is occasionally required to relieve these symptoms 11 .…”

“…Previous longitudinal studies on NAEB have focused on the prognosis concerning relapse and the development of chronic airflow obstruction [5][6][7] . However, NAEB patients could have respiratory symptoms other than cough, such as chest tightness with wheezing, shortness of breath, and sputum production [8][9][10] , and treatment with systemic corticosteroids is occasionally required to relieve these symptoms 11 . No studies have yet investigated the incidence and predictors of acute exacerbations, defined as worsened respiratory symptoms requiring systemic treatment, in this condition.…”