Table 5. Investigations for asthma.

Risk factors for poor asthma outcome
Assess risk factors at diagnosis and periodically (1 – 2 years) Measure FEV1 at the start of treatment and periodically
Independent risk factors	Having one or more of these risk factors increases the risk of exacerbations, even if symptoms are well-controlled: Uncontrolled asthma symptoms ICS not prescribed, poor ICS adherence, incorrect inhaler technique High short-acting β2-agonists (SABA) use Low FEV1, especially if <60% predicted Major psychological or socioeconomic problems Exposures: smoking; allergen exposure, if sensitised Co-morbidities: obesity, rhinosinusitis, confirmed food allergy Sputum or blood eosinophilia, elevated fractional exhaled nitric oxide in allergic adults Pregnancy Ever being intubated or in intensive care for asthma Having ≥1 severe exacerbations in the last 12 months
Risk factors for fixed airflow limitation	Lack of ICS treatment Exposure to tobacco smoke Noxious chemical or occupational exposures Low FEV1 Chronic mucus hypersecretion Sputum or blood eosinophilia
Risk factors for medication side effect	Systemic: frequent oral corticosteroids (OCS); long-term, high-dose ICS; taking P450 inhibitors, e.g. itraconazole, ketoconazole, etc. Local: high-dose or potent ICS, poor inhaler technique