According to the latest report released in December 2010 from the Center for National Health Statistics at the US Centers for Disease Control and Prevention, chronic lower respiratory diseases, which include chronic obstructive pulmonary disease (COPD), have replaced stroke as the third leading cause of death in the United States.1,2
COPD is characterized by progressive airflow limitation that is not fully reversible. Almost 13 million people in the United States were diagnosed with COPD in 2006, but the overall prevalence of COPD in the United States has been estimated at 24 million, indicating substantial underdiagnosis.3,4
As such, better recognition and management of COPD and its exacerbations are required to reduce the clinical and economic burden of this chronic, progressing disease. Current therapies focus almost solely on airway obstruction and consist mainly of bronchodilators.
Despite the efficacy of current pharmacotherapies in controlling symptoms, they do not change the natural history of the disease, and many patients remain symptomatic.
At the 2010 annual meeting of the American College of Chest Physicians (Chest 2010), new and emerging therapies for COPD and state-of-the-art management of the disease were highlighted in more than 20 scientific plenary sessions, symposia, panel discussions, oral abstract sessions, and poster sessions.
Potential future therapies also received special emphasis, given the scope, morbidity, and mortality of COPD.
The State of COPD Therapy
As discussed in this publication, new beta-agonists, anticholinergics, and combination therapies are under development to better address the multifactorial nature of COPD and enhance patient adherence to medication regimens.
New therapies for COPD currently in development and presented in this supplement address other aspects of COPD, such as inflammation, mu cociliary dysfunction, and airway scarring and remodeling.
Many of the novel agents being developed are once-daily therapies, an important advance in patient acceptance and adherence.
Delivery Systems Can Affect Treatment Efficacy, Patient Adherence
Several methods of aerosol drug delivery are available, and improvements to their design are improving the efficiency of drug delivery.
Inefficient delivery of drug to the lungs is a problem with current pressurized metered-dose inhalers (MDIs) and dry powder inhalers, and pressurized MDIs have the added drawback of requiring coordination be tween their actuation and breath inhalation for optimal efficacy.
Nebulized therapy is making inroads, because nebulizers require no such coordination between actuation and inhalation and can be used effectively in patients with low peak inspiratory flow rates.
The 2 classes in development that may provide unexpected benefits in COPD are phosphodiesterase (PDE) 4 inhibitors and peroxisome proliferator-activated receptor agonists.
Importance of COPD Exacerbations
Our understanding of COPD exacerbations is evolving, as new data indicate the serious impact of an acute exacerbation on mortality. More than one third of patients with COPD will die within 4 years of a first acute exacerbation. In one study reported here, an acute exacerbation was typically preceded by 10 days of worsening symptoms and worsening pulmonary function.
Preventing exacerbations in COPD is therefore essential for limiting the decline in lung function that can lead to exacerbations. Long-acting bronchodilators and inhaled corticosteroids have been shown to de crease the rate of exacerbations in COPD.
Theoretically, antibiotics would have a positive impact in this regard, because bacterial infection is an important risk factor in COPD exacerbations; preliminary evidence indeed shows that cyclical antibiotics may reduce the risk of exacerbation, as discussed by Dr Hanania.
A new agent—roflumilast, a PDE 4 inhibitor—is in late-phase development in the United States but is already ap proved in Europe; in clinical trials, roflumilast reduced the rate of moderate or severe exacerbations of COPD.
COPD Therapies Must Address an Inflammatory State
Comorbidities are abundant with COPD, and treatments have differential effects on some of the many systemic manifestations of COPD. The inflammation that characterizes COPD may represent a generalized inflammatory state, and this inflammation may initiate or worsen comorbid conditions.
Some of the diseases that often coexist with COPD are cardiovascular disease (ischemic heart disease, heart failure), skeletal muscle weakness and osteoporosis, depression and anxiety disorders, anemia, and obstructive sleep apnea.
Treatment of COPD inflammation may therefore concomitantly treat systemic inflammation and associated comorbidities. For instance, inhaled corticosteroids appear to decrease the risk of heart attack in patients with COPD. Some therapies that may serve to calm the inflammatory state of COPD are broad-spectrum antiinflammatory treatments.
- Centers for Disease Control and Prevention. Strokes drops to fourth leading cause of death in 2008. Press Release. December 9, 2010. www.cdc.gov/media/pressrel/2010/r101209.html. Accessed January 4, 2011.
- Centers for Disease Control and Prevention. National Center for Health Statistics, 1960-2010. www.cdc.gov/nchs/data/about/nchs_50th_brochure.pdf. Accessed January 4, 2011.
- Pleis JR, Lethbridge-Cejku M. Summary health statistics for U.S. adults: National Health Interview Survey, 2005. Vital Health Stat 10. 2006;232:1-153.
- Yawn BP. Differential assessment and management of asthma vs chronic obstructive pulmonary disease. Medscape J Med. 2009;11:20.