Asthma
Definitions
Atopy: predisposition to generate IgE vs environmental antigens.
Mechanisms of asthma:
- type 2 = allergic / eosinophilic. Generally assocaited with elevated FeNO and Blood Eosinophilia
- non type-2 = neutrophilic and other. Less responsive to inhaled corticosteroid. More often later onset, associated with obesity, and preferential effects women.
Diagnosis
Symptoms
- varying in intensity
- nocturnal (but never early at night)
- exposure provoked
- wheeze/cough/tightness
##Assessment
severity: determines initial treatment controlled (assess with a std questionnaire)
- impairment (symptoms are well/not well/very poorly controlled). peak flow not helpful
- risk (number of exacerbations)
##Management Have asthma action plan:
If well controlled for 3 weeks (months? per NHLBI), step down therapy.
Mild asthma (either intermittent or persistent) - can use symbicort (budesonide / formoterol - because the formoterol is fast onset)
- the idea is to avoid a lot of ICS use.
Singulair = black box warnings (neuropsychiatric)
When severe, look for other things (e.g. IgE, Eos elevated for IL-5 and IL-4 respectively).
Reliever
Both GINA 2020 and NHLBI update recommend budesonide-formoterol over albuterol in a variety of circumstances. Why?
-SABA use masks insufficient ICS. Increasing ICS can avert exacerbations, SABAs can't. -poor adherence to ICS with intermittent symptoms when separate -safety concerns from SABA overuse
https://erj.ersjournals.com/content/53/4/1802223
