Asthma is a condition characterized by three pathologic processes: airway inflammation, airflow obstruction, and airway hyper-responsiveness. Asthma is often diagnosed once there are signs and symptoms, but asthma can still exist even without obvious manifestations, such as when medical control has been achieved.
On the other hand, an asthma attack, also known medically as asthma in acute exacerbation, is a sudden deterioration in a person with asthma. It is characterized by the acute worsening of asthma signs and symptoms. In other words, someone having an asthma attack complains of more frequent or more severe symptoms, with different measurable parameters of lung function also showing deterioration.
A person with asthma that has been controlled sufficiently experiences no symptoms, despite the fact that the pathology is present.
What is an “acute exacerbation”? According to the official statement of the American Thoracic Society and the European Respiratory Society, a severe exacerbation is described as one that necessitates admission to the hospital or visits to the emergency room (ER), or three days’ use of corticosteroids given systemically. A moderate exacerbation may not need systemic corticosteroids but may necessitate other drugs. It may also show a worsening of one’s signs and symptoms in at least two days—but without the need for any ER consult or hospitalization.
There is a need to conduct more studies that will define asthma attacks based on more reliable criteria. A review of the Steroid Treatment as Regular Therapy in early asthma (START) study showed how severe exacerbations (“asthma attacks”) meant a faster decline in lung function. It is therefore important that exacerbations be identified and diagnosed accurately.