Dennis K. Ledford; Richard F. Lockey


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

In This Article

Chronic Obstructive Lung Disease

Chronic obstructive lung disease (COPD) is characterized by airflow obstruction that is not fully reversible. Sixty percent of participants in COPD trials exhibit 15% improvement in forced expiratory volume in one second with aggressive bronchodilator therapy but not improvement to normal. This condition is associated with cigarette smoking, but up to 15–20% of affected individuals do not have a significant history of cigarette smoking. Only a minority of cigarette smokers develop COPD indicating that host factors, in addition to irritants from the cigarette smoke, are essential for disease development. Approximately 24 million people in the United States were estimated to have COPD in 2008, and probably less than 50% of those affected are diagnosed at any given time. In the United States alone, 672 000 hospitalizations for COPD occurred in 2006 and 124 477 deaths in 2007. COPD was the third leading cause of death in the United States, and worldwide COPD is the fourth or fifth most common cause of death.

Relationship to Asthma

The symptoms of COPD and asthma are very similar: cough, mucous production, and shortness of breath. Although wheezing is associated with asthma, individuals with COPD frequently wheeze and all asthma patients do not wheeze. This diagnostic challenge is further compounded by a subset of asthmatic patients who develop irreversible airflow obstruction, resembling COPD.

Diagnostic or Therapeutic Considerations

Onset of symptoms prior to the age of 30 years, a personal or family history of atopic disease, upper airway disease, and mucosal and/or peripheral blood eosinophilia support a diagnosis of asthma. Cigarette smoking increases the likelihood of COPD. Having both conditions is not unusual. Treatment of both obstructive airway conditions is similar, although the focus for COPD is regular bronchodilator therapy with inhaled corticosteroids added for more severe disease. This contrasts with the recommendation to utilize anti-inflammatory therapy early in the asthmatic disease process and to avoid regular use of bronchodilator therapy. Inhaled anticholinergic therapy is approved in COPD but not asthma, although anticholinergic therapy is effective in asthma.[2528]

In summary, COPD and asthma share clinical features confounding the diagnosis of the two conditions. Although COPD and asthma are viewed by some as totally separate conditions, others consider these disorders as part of a continuum of airflow obstruction. Treatment approaches are similar with the exceptions noted.