What is the recommended stepwise approach for diagnosing, classifying control, and managing asthma in primary care, including trigger avoidance, vaccination, inhaler technique, pharmacologic therapy, and acute exacerbation treatment?

Asthma Management in Primary Care

Asthma management in primary care follows a stepwise approach based on initial severity classification and ongoing control assessment, with inhaled corticosteroids as the cornerstone of persistent asthma treatment and regular monitoring to step up or step down therapy as needed. 1

Initial Diagnosis and Severity Classification

Diagnostic Criteria

• Establish diagnosis through variable symptoms and objective lung function testing demonstrating ≥20% variability in peak expiratory flow (PEF), either during symptomatic periods in patients with normal baseline PEF, or improvement after bronchodilator or treatment in those with reduced PEF 2
• Measure FEV₁ and FEV₁/FVC ratio at diagnosis using spirometry 1

Severity Classification (Before Treatment Initiation)

Classify severity based on both impairment and risk domains for patients ≥12 years 1:

Intermittent Asthma:

• Symptoms ≤2 days/week 1
• Nighttime awakenings ≤2 times/month 1
• SABA use ≤2 days/week 1
• No interference with normal activity 1
• FEV₁ >80% predicted, normal FEV₁/FVC 1
• 0-1 exacerbations/year requiring oral corticosteroids 1

Mild Persistent:

• Symptoms >2 days/week but not daily 1
• Nighttime awakenings 3-4 times/month 1
• SABA use >2 days/week but not daily 1
• Minor limitation of activity 1
• FEV₁ >80% predicted, normal FEV₁/FVC 1

Moderate Persistent:

• Daily symptoms 1
• Nighttime awakenings >1 time/week but not nightly 1
• Daily SABA use 1
• Some limitation of activity 1
• FEV₁ 60-80% predicted, FEV₁/FVC reduced >5% 1

Severe Persistent:

• Symptoms throughout the day 1
• Nighttime awakenings often 7 times/week 1
• SABA use several times per day 1
• Extremely limited activity 1
• FEV₁ <60% predicted, FEV₁/FVC reduced >5% 1

Critical caveat: Patients with ≥2 exacerbations requiring oral corticosteroids in the past year should be considered to have persistent asthma regardless of other features 1

Assessing Asthma Control (For Ongoing Management)

Control Classification for Patients ≥12 Years

Use the most severe impairment or risk category to determine overall control 1:

Well Controlled:

• Symptoms ≤2 days/week 1
• Nighttime awakenings ≤2 times/month 1
• SABA use ≤2 days/week 1
• No interference with normal activity 1
• FEV₁ or PEF >80% predicted/personal best 1
• 0-1 exacerbations/year requiring oral corticosteroids 1
• Validated questionnaire scores: ACT ≥20, ATAQ = 0, ACQ ≤0.75 1

Not Well Controlled:

• Symptoms >2 days/week 1
• Nighttime awakenings 1-3 times/week 1
• SABA use >2 days/week 1
• Some limitation of activity 1
• FEV₁ or PEF 60-80% predicted/personal best 1
• ≥2 exacerbations/year 1
• ACT 16-19, ATAQ 1-2, ACQ ≥1.5 1

Very Poorly Controlled:

• Symptoms throughout the day 1
• Nighttime awakenings ≥4 times/week 1
• SABA use several times per day 1
• Extremely limited activity 1
• FEV₁ or PEF <60% predicted/personal best 1
• ACT ≤15, ATAQ 3-4 1

Validated Self-Assessment Tools

• Use the Asthma Control Test (ACT), Asthma Control Questionnaire (ACQ), or Asthma Therapy Assessment Questionnaire (ATAQ) at each visit for rapid assessment 1
• These tools assess current impairment but not the risk domain 1

Environmental Control and Trigger Avoidance

Essential Interventions

• Identify and avoid relevant allergens including house dust mite, domestic pets, and pollens 1
• Document smoking status at every visit and advise all patients who smoke to stop 1
• Advise patients to avoid passive smoking 1
• Consider nicotine replacement therapy to assist with smoking cessation 1
• Avoid nonsteroidal anti-inflammatory drugs in aspirin-sensitive asthma 1
• Avoid β-blockers entirely, even β₁-selective agents, as they can induce bronchospasm 1
• Treat comorbid gastroesophageal reflux disease when present 1

Vaccination Recommendations

• Administer influenza vaccination annually to all asthma patients due to their increased risk of influenza-associated complications 1
• Note that influenza vaccination should not be expected to reduce asthma exacerbation frequency or severity 1

Inhaler Technique and Device Selection

Device Selection Algorithm

• Start with a metered-dose inhaler (MDI) for all patients 1
• If patient cannot use MDI properly, add a large volume spacer device 1
• Spacers enhance drug distribution and effectiveness for everyone using MDI 1
• If MDI plus spacer is too bulky for daytime portability, switch to the least expensive powder inhaler or automatic aerosol device the patient can use correctly 1

Critical Practice Point

• Verify proper inhaler technique at every visit before considering treatment escalation 1
• Poor technique is a common cause of apparent treatment failure 1

Stepwise Pharmacologic Therapy

Treatment Initiation Based on Severity

Initiate therapy at the step corresponding to disease severity 1:

Intermittent Asthma:

• SABA as needed only 1

Mild Persistent:

• Low-dose inhaled corticosteroid (ICS) 1
• Alternative: leukotriene receptor antagonist 1

Moderate Persistent:

• Low-dose ICS plus long-acting β₂-agonist (LABA) 1
• Alternative: medium-dose ICS alone 1

Severe Persistent:

• Medium-to-high-dose ICS plus LABA 1
• Consider adding leukotriene receptor antagonist or theophylline 1

Adjusting Therapy Based on Control

For Well-Controlled Asthma:

• Maintain current step with follow-up every 1-6 months 1
• Consider stepping down after ≥3 months of good control to identify minimum medication necessary 1

For Not Well-Controlled Asthma:

• First verify adherence, inhaler technique, environmental control, and comorbid conditions before stepping up 1
• Step up one step and reevaluate in 2-6 weeks 1
• If using alternative therapy, discontinue and switch to preferred treatment before stepping up 1

For Very Poorly Controlled Asthma:

• Consider short course of oral corticosteroids 1
• Step up 1-2 steps 1
• Reevaluate in 2 weeks 1

Key Medication Principles

Inhaled Corticosteroids:

• ICS are the most consistently effective anti-inflammatory therapy for persistent asthma at all steps 1
• Most effective for controlling symptoms and preventing exacerbations 1

Long-Acting β₂-Agonists:

• Never use LABA as monotherapy—always combine with ICS 1
• Daily LABA dose should not exceed 100 mcg salmeterol or 24 mcg formoterol 1
• Instruct patients never to stop ICS while taking LABA 1
• LABA should not be used for acute symptoms or exacerbations 1

Oral Bronchodilators:

• Consider as second-line to inhaled bronchodilators 1
• Oral agents act more slowly and are less suitable for acute symptom relief 1

Acute Exacerbation Management

Treatment Protocol

• Administer oral corticosteroids (prednisolone 30-40 mg daily) until lung function returns to previous best 1
• Seven days of treatment is often sufficient, but may continue up to 21 days 1
• Oral corticosteroids are equally effective as intravenous administration 1
• Short courses (≤2 weeks) do not require tapering—can stop from full dose 1
• Deliver SABA via nebulizer or large volume spacer depending on severity 1

Indications for Rescue Corticosteroids

• Day-by-day worsening symptoms 1
• PEF <60% of patient's best 1
• Sleep disturbance until midday 1
• Diminishing response to inhaled bronchodilators 1
• Emergency use of nebulized or injected bronchodilators 1

Monitoring and Follow-Up

Regular Assessment Schedule

• Assess control at every visit using impairment and risk domains 1
• Recall symptoms over previous 2-4 weeks 1
• Measure FEV₁ or PEF at each visit 1
• For longer assessment periods, use global questions like "Is your asthma better or worse since last visit?" 1

When to Refer to Specialist

Refer for consultation or comanagement when 1:

• Difficulty achieving or maintaining control 1
• Patient required ≥2 bursts of oral corticosteroids in 1 year 1
• Exacerbation requiring hospitalization 1
• Step 4 care or higher required (Step 3 or higher for children 0-4 years) 1
• Considering immunotherapy or omalizumab 1
• Additional testing indicated 1

Common Pitfalls to Avoid

• Do not increase therapy without first checking adherence, inhaler technique, environmental triggers, and comorbidities 1
• Do not accept ongoing symptoms or frequent SABA use as "normal" for asthma patients 1
• Do not use LABA without concurrent ICS 1
• Do not assume influenza vaccination will reduce exacerbation frequency 1
• Recognize that patients with intermittent asthma can still experience severe exacerbations 1