Special Considerations in Asthma Management
COVID-19 Well-controlled asthma, without significant comorbidities, not requiring high-dose ICS or regular oral corticosteroids, and not having frequent acute exacerbations requiring extra bursts of systemic corticosteroids, is not associated with a higher risk of infection with the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus or its complications. Individuals with sev
COVID-19
Well-controlled asthma, without significant comorbidities, not requiring high-dose ICS or regular oral corticosteroids, and not having frequent acute exacerbations requiring extra bursts of systemic corticosteroids, is not associated with a higher risk of infection with the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus or its complications. Individuals with severe asthma or uncontrolled asthma have a greater risk of dying from COVID-19 infection and therefore asthma should be managed appropriately with inhaled corticosteroids. Those receiving biologic therapies should continue treatment. Asthma treatment must not be stopped as asthma exacerbations will worsen COVID-19 disease risks.
People with asthma should continue to respect COVID rules of social distancing, mask wearing and obtain COVID vaccination.
Guidance on the use of nebulisers and lung function testing are available on the SATS website (www.pulmonology.co.za).
Asthma in pregnancy
Asthma control is important and should ideally be optimised prior to conception and maintained throughout pregnancy and during the puerperium. Use of treatment over time has confirmed the safety of most commonly recommended asthma drugs and that the risks of poor asthma control during pregnancy outweigh any potential risk of the usual reliever and controller therapies.[1,47] These include beclomethasone dipropionate, budesonide, SABAs, LABAs, ipratropium bromide, theophylline and oral corticosteroids. They should not be stopped during pregnancy as poor asthma control poses a greater risk to mother and child than any unlikely adverse effect of these treatments. In general, asthma control remains the same in one-third of pregnant asthma patients, worsens in one-third and improves in one-third, and may vary during each of the three trimesters and with subsequent pregnancies. This warrants regular asthma assessment during pregnancy. Optimal asthma control is associated with the best pregnancy outcomes. Of the newer biologic therapies, some safety data exist for omalizumab in pregnancy.[38]
Vocal cord dysfunction
Vocal cord dysfunction may mimic asthma and or worsen asthma symptoms. Patients may have typical asthma symptoms without significant airflow limitation when tested. Visual inspection of the cords may reveal paradoxical movement of the cords. Explanation and counselling are important and symptoms may respond to intensive speech therapy.
Occupational asthma
Industrialisation is paradoxically associated with increased asthma prevalence owing to the increased production of, and exposure to, respirable irritants and allergens. Exposure to these agents may cause or aggravate asthma and must be considered in adult-onset asthma, difficult-to-control or severe asthma. In principle, the diagnosis of occupational asthma requires the diagnosis of asthma and demonstration of a clear association with workplace exposure to a known or potential airway irritant or allergen and asthma symptoms. If occupational asthma is suspected, the patient should be referred to a pulmonologist or a centre of expertise for investigation. Early removal from exposure can significantly mitigate the development of chronic asthma. Occupational asthma related to a proven causative agent is a scheduled occupational disease under the Occupational Diseases in Mines and Works Amendments Acts of 1994 and 2002 and subject to compensation under the Compensation for Occupational Injuries and Diseases Amendments Acts of 1994 and No. 61 of 1997.
Exercise-induced bronchoconstriction
Exercise is important for overall health and wellbeing but may trigger symptoms of asthma. However, exercising on days with high pollution or pollen counts should where possible be avoided. Pre-exercise use of a short- or long-acting beta agonist and sufficient warm-up reduces the risk of exercise-induced asthma (Evidence A).[8] If an individual is using ICS-formoterol as their reliever, this can be considered for use pre-exercise rather than a SABA (Evidence B).[48] Advising an athlete to avoid triggers such as training on very hot or cold days and avoiding allergen exposure may reduce the risk of bronchospasm. Clinicians must be cognisant of rules and regulations regarding therapeutic use exemptions and, if asthma symptoms remain uncontrolled, the patient should be referred to a specialist for evaluation.
Irritant-induced asthma
Irritant-induced asthma (previously known as reactive airways dysfunction syndrome (RADS) if asthma occurs following a single high-level exposure to an irritant)
RADS is a condition that occurs after exposure to a high concentration of an airway irritant, usually in a confined space and owing to an industrial accident in a non-atopic, non-asthmatic person and presents with acute respiratory distress owing to injury to the airways. It may be fatal or result in severe airway obstruction warranting emergency treatment. It often leads to chronic asthma. Irritant-induced asthma may also occur owing to persistent low-dose exposure to airborne irritants over months to years.[49]
Rhinosinusitis
It is estimated that 80% of asthmatics have concomitant rhinosinusitis, and about 50% of patients with rhinosinusitis have asthma. Anatomically, the upper and lower respiratory tracts are embryonically linked and subject to similar inflammatory processes, and secretions from a postnasal drip enter the lower respiratory tract, causing inflammation. Uncontrolled rhinosinusitis can lead to poor asthma control and vice versa. It is recommended that sinus disease is assessed and treated appropriately, particularly if asthma is not well-controlled or severe.
Gastro-oesophageal reflux disease (GORD)
GORD is a common cause of heartburn and dry cough and may contribute to poor asthma control. In patients with GORD, treatment with a proton pump inhibitor is recommended (Evidence A). GORD may worsen vocal cord dysfunction which may mimic asthma. Empiric treatment of GORD without symptoms in uncontrolled asthma patients is not recommended as it is has not been shown to improve the asthma control.[1]
Asthma-COPD overlap (ACO)
Asthma and COPD may exist in the same patient. It may be difficult to differentiate asthma from COPD in some patients, as the symptoms and clinical features of both asthma and COPD overlap. These patients may be considered to have ACO. No formal definition or treatment algorithm exists for patients with coexistent asthma and COPD. The default therapy should be with ICSs, given their importance in asthma management,[7] and additional LABA and/or LAMA are also needed in most cases.
Difficult-to-treat v. severe asthma
In clinical practice, many patients may be on medication that would place them in the GINA step 5 category – traditionally part of the ‘severe asthma’ definition. Many patients may not be truly severe but rather difficult-to-treat, and attention to factors influencing asthma control as listed below may result in a reduction in medication requirements.
These subgroups of asthmatics should be evaluated at a specialist centre. It is estimated that between 5 and 10% of asthmatics are truly severe, and the differentiation from difficult-to-treat is important prior to escalating to expensive (biologic) and harmful (long-term oral corticosteroid) therapies. For those with potentially severe asthma characterised by ‘ongoing/uncontrolled symptoms despite optimised high-dose ICS-LABA combination therapy or requiring high-dose ICS-LABA to prevent it being uncontrolled’,[1] a specific workup should be conducted to confirm the need for high-dose corticosteroids or biologic therapy.
The American Thoracic Society/European Respiratory Society (ATS/ERS) and GINA guidelines on severe asthma provide detailed guidance.[50,51] Once the diagnosis of asthma is confirmed, work-up would include evaluation of:
- adherence and inhaler technique
- uncontrolled rhinosinusitis/(adults), nasal polyps
- psychological factors, e.g. personality trait, symptom perception, anxiety, depression
- smoking/smoking-related disease
- vocal cord dysfunction
- obesity and obstructive sleep apnoea
- hyperventilation syndrome
- hormonal influences, e.g. premenstrual, menarche, menopause, thyroid disorders
- medications, e.g. aspirin, non-steroidal anti-inflammatory drugs (NSAIDs), β-adrenergic blockers, angiotensin-converting enzyme inhibitors.
Guidelines for the management of asthma in adults and adolescents, South African Thoracic Society, 2021