Definition of acute asthma exacerbations in adults and children: differentiating asthma exacerbations from poor asthma control

In the Global Inititative for Asthma (GINA) guidelines,1 exacerbations are defined as ‘episodes of rapidly progressive increase in shortness of breath, cough, wheezing, or chest tightness, or some combination of these symptoms. Respiratory distress is common. Exacerbations are characterised by decreases in expiratory airflow that can be quantified by measurement of lung function …’. A similar definition is provided in the US guidelines.2