COPD Update

Chronic obstructive pulmonary disease (COPD) is a common, preventable and treatable disorder that is characterized by airflow limitation that is not fully reversible. In 2004, 11.4 million U.S. adults were estimated to have COPD.(1) However, close to 24 million U.S. adults have evidence of impaired lung function, indicating an under diagnosis of COPD.(2) COPD is currently the forth leading cause of death in the US and is projected to become the third leading cause of death by 2020. More than 120,000 Americans die of COPD annually3 and over half (51%) of the deaths are among women.(3) COPD annual costs exceed $37 billion and account for 15 million physician office visits, 1.4 million ER visits and 675,878 hospitalizations annually.(4) Important medical considerations for COPD include prevention, early recognition, accurate diagnoses, management with proven treatments and use of a stepwise approach to evaluate and manage exacerbations and disease progression.

Screening should target patients with symptoms and / or findings suggestive of COPD:

Dyspnea (often on exertion, with stairs or inclines), cough or wheeze
Exposure to risk factors including current or previous history of smoking, exposure to occupational dusts, chemicals or indoor air pollution (burning of wood or biomass fuel in confined spaces) and genetic risk for deficiency of Alpha 1 antitrypsin evaluated through blood testing.

For persons at risk for COPD, accurate diagnosis is critical and targets evaluation with spirometry or pulmonary function testing. This simple outpatient test provides accurate information regarding diagnosis and severity. Some physiciansÕ offices use spirometry screening which measures airflow. Alternatively, patients can be referred to pulmonary function laboratory for testing. Full pulmonary function testing measures a range of robust diagnostic indices including flow rates, lung volumes, diffusion capacity and post bronchodilator response.

Reducing risk factors is key to preventing and limiting worsening of COPD. Smoking is the primary cause of COPD and disease-related mortality. Smoking cessation can substantially reduce the risk for development of COPD, rate of progression and mortality. National guidelines for smoking cessation are available at http://www.surgeongeneral.gov/tobacco/.

The Global initiative for COPD or GOLD guidelines5 target increasing awareness, improving management and reducing consequences of COPD. The guidelines goals for management of COPD include:
* Relief of symptoms
* Prevention of disease progression
* Improvement of health status and exercise tolerance
* Prevention and treatment of complications and exacerbations
* Reduction of mortality

An exacerbation is defined as an acute change in baseline symptoms (dyspnea, cough, and /or sputum) that may warrant a change in medication. The GOLD guidelines include treatment recommendations based on the stage of severity of COPD by spirometry findings. Spirometry evaluation includes forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and a ratio of FEV1/FCV. A FEV1/FVC ratio of less than 0.7 if used to define airflow limitation.

Stages of COPD and treatment recommendations include:
Stage of COPD
FEV1% predicted
Recommendations
Mild
>80%
Smoking cessation, avoidance of risk factors and short acting bronchodilator when needed
Moderate
50-80%
Regular treatment with one or more long acting bronchodilator and Pulmonary Rehabilitation
Severe
30-50%
Inhaled corticosteroids for frequent exacerbations
Very severe
< 30%
Long term oxygen for chronic respiratory failure and consider surgical treatment.

A comprehensive treatment plan for managing patients with COPD involves the use of pharmacological as well as nonpharmacologic interventions. Bronchodilator therapy is a basis for symptomatic treatment. Pulmonary Rehabilitation uses monitored, supervised exercise, disease self management education and support to improve function, symptom control, quality of life and reduce use of health care resources. Patients with hypoxemia normally require long-term oxygen therapy and should be evaluated for portable systems to promote independence. Surgical interventions, including lung transplantation and lung volume reduction surgery may be considered for some in more advanced stages of COPD. Influenza vaccine and pneumococcal polysaccharide vaccine are recommended for persons with COPD that are 65 years or over and all those with FEV1 < 40% predicted.

Clinicians play a critical role in disease recognition and management. Optimal management of COPD is through collaboration of the clinician, multidisciplinary team and patient based on international evidence-based guidelines.

References

1 National Center for Health Statistics. Raw Data from the National Health Interview Survey, U.S., 2003. (Analysis by the ALA Using SPSS and SUDAAN software).
2. Mannino DM, Homa DM, Akinbami L, et al. COPDisease Surveillance - U.S., 1997-2000. MMWR. Vol. 51 (SS06); 1-16.
3. Centers for Disease Control and Prevention, National Center for Health Statistics. Report of Final Mortality Statistics, 2002.
4 National Center for Health Statistics. National Ambulatory Medical Care Survey, National Hospital Ambulatory Medical Care Survey and the National Hospital Discharge Survey, 2002
5 http://www.goldcopd.com/