Dennis K. Ledford; Richard F. Lockey


Curr Opin Allergy Clin Immunol. 2013;13(1):78-86. 

In This Article

Abstract and Introduction


Purpose of review: This article summarizes the more common comorbidities which, in the opinion of the authors and supported by the medical literature, frequently affect asthma management. Optimal asthma control requires accurate diagnosis, implementation of effective therapy, and evaluation of coexisting conditions. Comorbidities refer to either coexisting conditions or interacting conditions, with the latter having a more significant influence on the management of asthma. This review provides the authors' clinical perspective of the more common comorbidities and relevant literature reviewed primarily from the past 4–5 years.

Recent findings: Optimizing rhinitis and rhinosinusitis management and addressing allergic sensitivity and allergen exposure are achievable measures for the most common asthma comorbidity. Psychological dysfunction and paradoxical vocal cord dysfunction are frequently associated with poor asthma control. The effects of obesity are inconsistent in the literature but obesity likely affects asthma symptoms and possibly its pathogenesis. Treatment of asymptomatic gastroesophageal reflux does not improve asthma.

Summary: Asthma is a common disease and other conditions frequently occur concomitantly in individuals with asthma. Asthma is usually very treatable and comorbidities should be considered and addressed or the asthma diagnosis questioned if treatment effects are not optimal. Evidence-based medicine is lacking as most asthma studies exclude comorbidities; additional studies are needed.


The term comorbidity is frequently misapplied if one accepts the preferred definition, that is, a coexistent disease or condition. In this context, comorbid conditions occur together but do not necessarily influence one another. In contrast, clinicians frequently use the term comorbidity to describe conditions that mutually affect the other, as such interactions complicate diagnosis, management, and assessment more than coincident diseases. Common diseases by coincidence will coexist with asthma due to the high prevalence of asthma, affecting approximately 8% of the adult population in the United States and up to 15% of children. In this article, the authors have taken the liberty of using asthma comorbidity when referring to a condition that influences asthma severity, management, or recognition or when referring to a disease affected by asthma. These relationships include increased severity of one or both diseases, an increased prevalence of one disease as a result of the other, a shared pathogenic process between the two, and misattribution of shared symptoms.

Asthma has a variable time of onset and clinical course. Comorbidities will vary with age and clinical context. Asthma control is based partially upon symptoms that are shared or influenced by many comorbid conditions. Misattribution of symptoms is a frequent influence of comorbidities on asthma assessment. For example, a condition such as gastroesophageal reflux disease (GERD), which is a comorbidity of asthma, may result in symptoms of cough and chest tightness without asthma. If both conditions are present, observed symptoms could result from worsening asthma independent of GERD, asthma could aggravate GERD and increase GERD symptoms, GERD could increase asthma symptoms or both conditions independently may result in similar complaints.