ERS 2022: Diagnostic Work-Up of Asthma: More Than Spirometry
Asthma is defined by a pattern of respiratory symptoms and variable expiratory flow limitation. Lung volume measurements like residual volume (RV) and total lung capacity (TLC) have been demonstrated as potential additional measures in evaluating asthma besides spirometry. The combined assessment of spirometry and body plethysmography in population-based cohorts is significantly less. Lung volume changes were analyzed in clinically diagnosed asthmatics who participated in the LEAD study, a single-centre, observational, longitudinal, population-based study of 11423 Austrians aged 6-82 years.
The study demonstrated that:
- Asthmatics had a lower FEV1/FVC ratio than the general population.
- TLC did not differ between asthmatics and the general population.
- The RV/TLC ratio was higher in asthmatics and the age groups 20-60 years and >60 years, but not in young asthmatics <20 years.
- RV/TLC% was especially high in asthmatics over the age of 60 years.
- Asthmatics had higher specific airway resistance, which was present in all age groups.
- A correlation between airway resistance and RV/TLC% was also found in both pre and post-BD asthmatics.
The study concluded that lung volumes are a reliable addition to spirometry. In addition, asthmatics over 20 may experience a progressive increase in RV/TLC and airway resistance, which may be related to airway remodelling.
European Respiratory Society (ERS) International Congress 2022, 3rd-6th Sept. 2022, Barcelona
