Proposed ABCD-3P-PQRST characterization system for asthma phenotypes, genotypes, and endotypes

AsthmaticsymptomsParoxysmal (< 1 month)
Persistent (1–6 months)
Permanent (> 6 months)
Precipitating factorsExertion (during, after), allergens, odors, drugs, tobacco smoke
Qualitative descriptionCough, wheezing, chest tightness, dyspnea
Reversibility to bronchodilatorAbsolute change, percent change
SeverityMild intermittent, mild, moderate, severe, or very severe persistent
TypeOnset (adulthood or childhood), race and ethnicity, gender (male or female, prepubertal, adult, postmenopausal)
BiomarkersPredominant cellsEffector cells: eosinophils, neutrophils, mast cells, mixed cellularity, paucicellular
Lymphocytes: T-helper 1 (Th1), Th2, Th17, regulatory T lymphocyes, natural killer cells
Predominant cytokines, immunoglobulins, moleculesInterleukin (IL) 4, IL-5, IL-9, IL-13, IL-33, periostin; interferon gamma, IL-15, IL-17, IL-18, IL-21, IL-22; immunoglobulin E or G; nitric oxide
Predisposing genotypeSpecific gene polymorphisms, mutations
Conditions associatedPrenatal risk factorsMaternal smoking, diet, nutrition, antibiotic use, stress
Postnatal risk factorsEarly-life wheezing, breastfeeding, early tobacco smoke exposure, viral infections, vitamin D deficiency, contact with animals, occupational exposures
Pathogenically linked conditionsAtopy, allergic rhinitis, chronic rhinosinusitis, nasal polyposis, obstructive sleep apnea, gastroesophageal reflux disease, obesity, bronchiectases
Drugs usedAnticholinergics (short-acting and long-acting), beta-2 adrenergic agonists (short-acting and long-acting), corticosteroids (inhaled, oral), leukotriene pathway-modifying agents (eg, leukotriene receptor agonists, lipooxygenase inhibitors), phosphodiesterase inhibitors (eg, theophylline, rofl umilast), cromolyn, nedocromil, mast cell stabilizers, anti–IL-5 agents (eg, mepolizumab, benralizumab, reslizumab), anti–IL-13 agents (eg, lebrikizumab, tralokinumab), anti-IgE (eg, omalizumab), anti-tumor necrosis factor alpha (golimumab)
  • a 3P model for disease persistence should be characterized clinically, functionally, and biologically (eg, including exhaled gas concentration of nitric oxide).