High-resolution computed tomography findings in elderly patients with asthma

Based on the hypothesis that airway remodelling is related to the duration of asthma, HRCT scanning should show greater abnormalities in the early-onset than the late-onset asthmatics. It was, therefore, intended to assess the presence and the frequency of airway and parenchymal abnormalities with high-resolution computed tomography (HRCT) in elderly asthmatic patients, and to determine whether these abnormalities are related to the duration of asthma.

Sixty-eight clinically stable asthmatic patients aged > or =60 yr were included in this prospective study. The patients were separated into two groups according to the duration of symptoms as late-onset asthma (n=31) with disease duration of <5 yr, and early-onset asthma (n=37) with disease duration of > or =5 yr. All patients were lifelong non-smoker and had been using inhaled beta agonists and inhaled steroids. HRCT-scanning and histamine inhalation test were performed on all patients.

In comparison with late-onset asthmatic patients, those with early-onset asthma had significantly higher frequency of emphysema (21.6% versus 0.0%, p=0.006), bronchial dilatation (13.9% versus 0.0%, p=0.03) and bronchial wall thickness (41.7% versus 12.9%, p=0.01). Multiple logistic regression analysis identified that early-onset of disease was an independent risk factor for the presence of irreversible HRCT-scan abnormalities in elderly asthmatics [odds ratio (OR): 9.4 (2.7-32.7), p=0.00001].

Present data suggest that HRCT abnormalities in early-onset elderly asthmatics reflect parenchymal and airway changes that become irreversible throughout the long course of the disease.