Long-term reduction of exacerbation risk should be a priority of asthma management in order to decrease risks to the patient and need for oral corticosteroids (which have important short-term and cumulative long-term adverse effects).[1] Even patients with few or no asthma symptoms (or asthma labeled as ''mild'') can have severe or fatal exacerbations, which may occur with unpredictable triggers (e.g., viral infection, allergen exposure, pollution, stress).[1] Asthma exacerbations are best prevented by long-term treatment with inhaled corticosteroids (ICS) and add-on medical therapy, in conjunction with treatment of modifiable risk factors such as avoidance of known asthma triggers (e.g., allergens and cigarette smoking), and treatment of comorbidities such as obesity and anxiety.[1][28][37] Add-on medical therapy (most commonly with a long-acting bronchodilator) not only improves asthma control but has been shown to reduce asthma exacerbations.[38]
ICS substantially reduce the risk of exacerbations and should be used in all patients with asthma.[1] The Global Initiative for Asthma (GINA) recommends starting ICS-containing drugs in all patients at diagnosis, or as soon as possible after, and advises that the importance of ICS-adherence should be emphasized to all patients.[1] GINA does not recommend short-acting beta-2 agonist-only treatment for asthma, due to the increased risk of severe exacerbations and mortality with this approach.[1] For adults and adolescents, GINA divides its recommendations into five treatment “steps” with preferred and alternative treatment options in each step listed as “Track 1” and “Track 2,” respectively.[1] The “Track 1” treatment approach is recommended where possible, as it is associated with a reduced risk of exacerbations (including severe exacerbations requiring oral corticosteroids), emergency department visits, and hospitalizations (compared with the “Track 2” approach).[1] See Asthma in adults (Management approach).
For adults who have persistent asthma, but who have suboptimal control of their asthma despite daily use of ICS with a long-acting bronchodilator, the addition of a long-acting muscarinic antagonist can be considered.[39] Leukotriene receptor antagonists can help to reduce moderate and severe asthma exacerbations and improve lung function and asthma control compared with the same dose of ICS alone. However, current evidence does not support leukotriene receptor antagonists as an ICS-sparing agent.[37]
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Note that there is the potential risk for neuropsychiatric adverse events (e.g., nightmares, mood and behavior problems, suicidal ideation) with montelukast use: benefits and risks should be carefully considered with the patient before use, and the patient should be closely monitored for these adverse effects during treatment.[1] To reduce the risk of exacerbations in patients with low forced expiratory volume in 1 second (FEV₁, especially <60% predicted) despite optimized inhaler technique and adherence to treatment, GINA advises that a 3-month trial of high-dose ICS treatment can be considered but emphasizes that high-dose ICS should only be used short-term (e.g., 3-6 months) to minimize potential adverse effects.[1] If there is no improvement in FEV₁ with high-dose ICS treatment, alternative lung pathologies should be considered and expert advice sought.[1]
To minimize exacerbation risk, all patients should have regular review by a healthcare professional and be educated in asthma self-management, including self-monitoring of symptoms and/or lung function and use of a written asthma action plan: together, these measures dramatically reduce morbidity, including significant reductions in asthma-related hospitalizations and emergency department or unscheduled clinic visits.[1] The use of a written, personalized asthma action plan should be strongly encouraged to support self-management and increase its effectiveness.[1][40] The asthma action plan helps patients to recognize when their asthma is deteriorating and how to respond appropriately: for example, increasing usual reliever and controller treatment, starting a short course of oral corticosteroids, and determining when to seek medical help.[1]
International guidelines also recommend treating modifiable risk factors and comorbidities (e.g., smoking, obesity, anxiety) and giving advice about nonpharmacologic therapies and strategies when appropriate (e.g., smoking cessation programs, physical activity, weight loss, avoidance of triggers).[1] Weight reduction may improve asthma outcomes in obese patients.[41] Allergen immunotherapy may be useful for reducing exacerbation risk in some patients with allergies.[1] Patients with suspected occupational asthma should be referred for expert advice promptly.[1] GINA recommends that patients with one or more risk factors for exacerbations should have more frequent review than patients at low risk.[1]
Further, international guidelines recommend checking inhaler technique and adherence frequently (e.g., at every visit).[1] Following training, inhaler technique worsens over time (with issues often recurring within 4-6 weeks of initial training); therefore, regular review and correction of technique is important.[1] Patients should be involved when choosing inhalers; using an inhaler that the patient prefers and can use correctly promotes adherence and reduces exacerbation risk.[1] In addition to basing the choice on evidence of effectiveness, potential barriers to correct use (e.g., arthritis, cognitive impairment) and adherence (e.g., cost, complicated regimen) should be considered.[1] Patients with few or infrequent symptoms (e.g., symptoms on ≤2 days/week) are unlikely to adhere to a daily ICS controller: in these patients GINA prefers a treatment approach where ICS is administered whenever the patient uses their reliever (preferably this is achieved using their “Track 1” approach; if using the “Track 2” approach, ICS delivered in combination with the reliever via a single inhaler is preferred but if unavailable, ICS may be administered via a separate inhaler taken straight after the reliever).[1] This ensures the patient receives at least some ICS, and avoids inappropriate short-acting beta-2 agonist-only treatment (the latter may control symptoms but leaves airway inflammation untreated and the patient at increased risk of exacerbations).[1] One 2022 Cochrane review reported that a range of digital interventions may lead to better adherence (particularly in those with poor adherence) and reduced exacerbations (based on low-certainty evidence).[1] Examples of interventions that appear to be effective are electronic monitoring of inhaler use, electronic inhaler reminders, and text messages.[1]
Several cross-sectional studies have shown low serum levels of vitamin D to be linked to impaired lung function, higher exacerbation frequency, and reduced corticosteroid response.[42] In adults with vitamin D deficiency and asthma, vitamin D supplementation may reduce the rate of asthma exacerbations requiring treatment with systemic corticosteroids.[1] More good-quality evidence is required before definitive clinical recommendations can be made regarding supplementation with vitamin D.[1][43][44]
Adults with asthma are at high risk of developing complications after contracting the influenza virus, yet many adults with asthma do not receive an annual influenza vaccination. One systematic review reported no significant safety concerns or increased risk of asthma-related outcomes (including exacerbations or hospitalizations) after live attenuated influenza vaccination in adults younger than 50 years with mild to moderate asthma.[1] Annual vaccination against seasonal influenza and H1N1 is advisable for all people with asthma. GINA advises that people with asthma should also be encouraged to follow their local immunization schedule for pneumococcal, respiratory syncytial virus, pertussis, and COVID-19 vaccinations.[1]