Asthma and COVID-19: Emphasis on Adequate Asthma Control

Abstract

Asthmatics are at an increased risk of developing exacerbations after being infected by respiratory viruses such as influenza virus, parainfluenza virus, and human and severe acute respiratory syndrome coronaviruses (SARS-CoV). Asthma, especially when poorly controlled, is an independent risk factor for developing pneumonia. A subset of asthmatics can have significant defects in their innate, humoral, and cell-mediated immunity arms, which may explain the increased susceptibility to infections. Adequate asthma control is associated with a significant decrease in episodes of exacerbation. Because of their wide availability and potency to promote adequate asthma control, glucocorticoids, especially inhaled ones, are the cornerstone of asthma management. The current COVID-19 pandemic affects millions of people worldwide and possesses mortality several times that of seasonal influenza; therefore, it is necessary to revisit this subject. The pathogenesis of SARS-CoV-2, the virus that causes COVID-19, can potentiate the development of acute asthmatic exacerbation with the potential to worsen the state of chronic airway inflammation. The relationship is evident from several studies that show asthmatics experiencing a more adverse clinical course of SARS-CoV-2 infection than nonasthmatics. Recent studies show that dexamethasone, a potent glucocorticoid, and other inhaled corticosteroids significantly reduce morbidity and mortality among hospitalized COVID-19 patients. Hence, while we are waiting for more studies with higher level of evidence that further narrate the association between COVID-19 and asthma, we advise clinicians to try to achieve adequate disease control in asthmatics as it may reduce incidences and severity of exacerbations especially from SARS-CoV-2 infection.

Association of increased basic salivary proline‐rich protein 1 levels in induced sputum with type 2‐high asthma

“…Asthma is a heterogeneous immunopathological disease, with features of chronic inflammation, airway hyperresponsiveness, mucus over secretion, and airway remodeling. 1 , 2 Estimates of the global prevalence of asthma in different populations range from 1% to 18% and as many as 300 million people have asthma globally with increasing annual cost to the healthcare system. 12 According to GINA, the diagnosis of asthma should be based on the patient's clinical symptoms combined with laboratory evidence of BPT or BDT.…”

“…Asthma, which is characterized by airway hyperresponsiveness, airway eosinophilic inflammation, mucus overproduction, and airway remodeling, is gradually becoming an increasingly common disease. Airway eosinophilic inflammation is a central feature of asthma 1–3 . Asthma is a heterogenous disease with different phenotypes, including type 2‐low and type 2‐high asthma.…”

“…Airway eosinophilic inflammation is a central feature of asthma. 1 , 2 , 3 Asthma is a heterogenous disease with different phenotypes, including type 2‐low and type 2‐high asthma. T‐helper type 2‐driven inflammation defines the major subphenotypes of asthma featuring airway eosinophilic inflammation.…”

Pathobiological bases of asthma-COVID-19 interaction: A theoretical viewpoint

“…[6] Furthermore, asthma is regarded as a risk factor for the development of viral lower respiratory tract infections. [7] Of the respiratory comorbidities associated with COVID-19, it is observed that patients with chronic obstructive pulmonary disease are at a higher risk of having severe COVID-19. [8] As such, in the early phase of the pandemic, a similar relationship was predicted between asthma and COVID-19.…”

PTPRH Alleviates Airway Obstruction and Th2 Inflammation in Asthma as a Protective Factor

“…1,2 Estimates of the global prevalence of asthma in different populations range from 1% to 18%, and as many as 300 million people have asthma globally with increasing annual cost to the health-care system. 3,4 Bronchial epithelium plays an important function in maintaining airway homeostasis, balancing repair, initiating airway inflammation and producing mucus in asthma due to its subtle role in regulating tolerance and specific immune responses. [5][6][7] Protein tyrosine phosphatases (PTP) family is involved in cellular functions in parthenogenesis of cancers including proliferation, differentiation and migration.…”