According to the NAEPP, asthma management should focus on anti-inflammatory therapy. Treatment should strive to prevent symptoms, maintain near-normal pulmonary function tests, maintain normal activity levels, decrease asthma exacerbations, and provide a simple therapeutic regimen with minimal side effects. Treatment regimens are based upon asthma severity, which is classified using pretreatment clinical features, including number of days per month with symptoms, number of nights per month with symptoms, PEFR or FEV1, and PEFR variability. Classifications are mild intermittent, mild persistent, moderate persistent, or severe persistent (Table 4).
|Table 4. Clinical Features and Pharmacotherapy of Asthma|
|Days with symptoms||< or = 2/week||3–6/week||Daily||Continual|
|Nights with symptoms||< or = 2/month||3–4/month||greater or = 5/month||Frequent|
|PEFR or FEV1*||> or = 80%||> or = 80%||60%–80%||< or = 60%|
|Quick relief||Short-acting inhaled beta2 agonist as needed|
|Long-term control||None||Low-dose inhaled corticosteroids OR Cromolyn or Nedocromil OR Sustained-release theophylline OR Antileukotriene agent||Medium-dose inhaled corticosteroid OR Low-medium dose inhaled corticosteroid and long-acting bronchodilator
If needed: Medium-high dose inhaled corticosteroid and long-acting bronchodilator
|High-dose inhaled corticosteroid and long-acting bronchodilator and long-term systemic corticosteroids#|
|*Expressed as a percent of predicted
Long-acting inhaled beta-agonist, sustained release theophylline, or beta-agonist tablets
#Attempt to reduce systemic steroid dose and maintain on high-dose inhaled corticosteroids
Guidelines for managing asthma focus on two areas—rescue therapy and long-term control. All patients should be prescribed a short-acting inhaled beta-agonist for as-needed rescue. Mild intermittent asthma does not require long-term control medication. As lung function worsens, anti-inflammatory therapy should be added. The most effective long-term control medications are the inhaled corticosteroids. Mast-cell stabilizing agents, antileukotriene agents, long-acting beta-agonists, anticholinergics, and theophylline may also be useful. NAEPP guidelines for pharmacotherapy (Table 4) feature a “step up, step down” concept, in which therapy is started at a level higher than the disease severity in order to gain rapid control. Depending on the patient’s progress, care may then be stepped up or down.
Short-acting inhaled beta-agonists are the mainstay of rescue therapy. Several agents having different receptor selectivity and duration of activity are available. All patients should be prescribed a short-acting inhaled beta-agonist. Therapy should be administered as 2-4 puffs up to 4 times per day, as needed.
Patients should track the frequency of rescue medication use to report to their physician. Studies from the late 1970s and early 1980s showed an association between frequent beta-agonist use and mortality from asthma. It is possible that regular beta-agonist use may lead to beta-receptor down regulation, leading to decreased airway responsiveness to inhaled beta-agonist. However, a more likely explanation is that increased beta-agonist use serves as a marker for disease progression, not as a cause of increased mortality.
Adverse effects of inhaled beta-agonists are related to sympathomimetic actions on the heart and central nervous system, including tachycardia, palpitations, agitation, and tremors. Hypokalemia may also occur due to intracellular shifts in patients receiving high-dose inhaled beta-agonists.