Asthma Severity Classification
This patient has mild persistent asthma according to NAEPP guidelines. 1, 2
Clinical Reasoning
The classification is determined by evaluating both impairment and risk domains, with the final severity assigned to the most severe category in which any feature occurs. 1, 2
Impairment Domain Analysis
Daytime symptoms: Coughing and wheezing twice weekly places her in the mild persistent category (>2 days/week but not daily). 3, 1
Nighttime awakenings: Three times per month falls into the mild persistent range (3-4 times/month). 3, 1
Activity limitation: She reports no limitation of activities, which is consistent with well-controlled or mild disease. 1
Lung function: FEV₁ of 82% predicted is >80%, which meets criteria for either intermittent or mild persistent asthma. 3, 1, 2
SABA use: She uses albuterol approximately twice weekly (matching her symptom frequency), which exceeds the ≤2 days/week threshold for intermittent asthma. 1
Risk Domain Analysis
Exacerbation history: No documented history of oral corticosteroid courses or hospitalizations. 1, 2
Final Classification Logic
The most severe impairment feature determines the classification. 1, 2 While her FEV₁ (82%) could fit intermittent asthma, her symptom frequency (twice weekly) and nighttime awakenings (3 times/month) both exceed intermittent criteria and place her squarely in mild persistent asthma. 3, 1
Key Distinguishing Features
Intermittent asthma requires: ≤2 days/week symptoms, ≤2 nighttime awakenings/month, ≤2 days/week SABA use, FEV₁ >80%, and 0-1 exacerbations/year. 3, 1
Mild persistent asthma requires: >2 days/week but not daily symptoms, 3-4 nighttime awakenings/month, >2 days/week SABA use, FEV₁ >80%, with normal FEV₁/FVC ratio. 3, 1
This patient exceeds intermittent criteria in two domains (symptom frequency and nighttime awakenings), making mild persistent the appropriate classification. 1, 2
Common Pitfalls
Do not be misled by the relatively preserved FEV₁ of 82%. 1, 2 Lung function >80% can occur in both intermittent and mild persistent asthma—the distinction depends on symptom frequency and nighttime awakenings. 3, 1
Do not underestimate severity based on lack of activity limitation. 3 Patients often accept ongoing symptoms as "normal" and may not report functional impairment even when disease control is suboptimal. 3
Remember that severity classification is based on pre-treatment status. 3, 1 Since this patient has never been formally diagnosed or treated (only borrowed albuterol), this represents her baseline untreated severity. 1
Treatment Implications
Mild persistent asthma requires daily controller therapy. 1 The preferred regimen is low-dose inhaled corticosteroid (approximately 100-250 µg fluticasone-equivalent daily) plus as-needed SABA. 1
Alternative options include: leukotriene receptor antagonist, cromolyn, nedocromil, or theophylline, though these are less effective than inhaled corticosteroids. 1
Patients with ≥2 exacerbations requiring oral corticosteroids in the past year should be treated as having persistent asthma regardless of other features. 3, 1, 2 This patient has no such history, but this principle is critical for future monitoring. 1, 2