Abstract
Background: Recent epidemiologic evidence suggests that asthma is prevalent in the elderly population. Majority of elderly asthma develops in later life, and thus is considered patho-physiologically distinct from young adult asthma.
Objective: To investigate whether elderly asthmatics may have different phenotypic or pathophysiologic features from young adult asthmatics
Methods: Young adult (18-45 years) and elderly (≥65 years) non-smoking, treatment-naive asthmatics were compared cross-sectionally. Asthma was defined if they had typical symptoms and methacholine PC20 ≤ 8 mg /mL. They completed baseline spirometry, induced sputum analyses, inhalant allergen skin prick tests, and anthropometric measurements. As indices of small airway involvements, a FEF25-75% and FEF25-75/FVC were used.
Results: A total of 103 young adult (mean age: 29.9 year) and 120 elderly (mean age: 71.1 year) asthmatics were included. Two age groups had similar degrees of airway hyperresponsiveness (methacholine PC20; 2.7 ± 2.2 mg/mL in the elderly vs. 2.7 ± 2.5 mg/mL in young adults). They also did not differ in gender distribution, FVC%, or FEV1%. However, the elderly asthmatics had higher body mass index (24.9 kg/m2 vs. 23.3 kg/m2, P<0.05), and lower atopy prevalence (40.0% vs. 95.5%, P<0.001), and slightly lower sputum eosinophils (7.1% vs. 10.3%, P<0.1) than young adult asthmatics. In addition, the elderly had significantly reduced FEF25-75% (43.1% vs. 61.6%) and FEF25-75/FVC (0.52 vs. 0.72) than the younger subjects at baseline (all P<0.001).
Conclusions: Elderly asthmatics had different phenotypic and pathophysiologic features from young adult asthmatics, suggesting their distinct pathogenic mechanisms and therapeutic considerations.
- © 2012 ERS