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Revisiting Mild Asthma

Current Knowledge and Future Needs
Published:September 17, 2021DOI:https://doi.org/10.1016/j.chest.2021.09.004
      Asthma is a common chronic airways disease with significant impact on patients, caregivers, and the health care system. Although most research and novel interventions mainly have focused on patients with uncontrolled severe asthma, most patients with asthma have mild disease. Epidemiologic studies suggest that many patients with mild asthma report frequent exacerbations of the disease and uncontrolled symptoms. However, despite its impact, mild asthma does not have either a uniformly agreed on definition for or a consensus on its clinical and pathophysiologic progression. More recently, the approach to treatment of patients with mild asthma has undergone significant changes primarily based on emerging evidence that airway inflammation in this population is important. This led to clinical research studies that explored the efficacy of as-needed inhaled corticosteroids along with the rescue medications that traditionally have been the mainstay of treatment. Despite some advancement in the field in recent years, many controversies and unmet needs remain. In this review, we examine the current understanding of the pathophysiologic features and management of mild asthma. In addition, we outline unmet needs for future research. We conclude that mild asthma contributes significantly to the morbidity and mortality of asthma and should be the focus of future research.

      Key Words

      Abbreviations:

      Feno (fraction of exhaled nitric oxide), GINA (Global Initiative for Asthma), ICS (inhaled corticosteroids), LABA (long-acting β2-agonist), LTRA (leukotriene receptor antagonist), NAEPP (National Asthma Education and Prevention Program), SABA (short-acting β2-agonist), SYGMA (Symbicort Given as Needed in Mild Asthma)
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