BETHESDA, MD—Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death worldwide, yet it remains underdiagnosed and is often inappropriately treated. In aninternational effort to raise awareness of COPD and improve its management, the National Heart, Lung, and Blood Institute and World Health Organization have undertaken the Global Initiative for Chronic Obstructive Lung Disease (GOLD).

GOLD’s first concern was to produce evidence-based COPD guidelines for worldwide use.[1] The guidelines focus on assessment and monitoring, risk-factor reduction, and management of stable disease and acute exacerbations.

“One of our goals is to help practitioners recognize COPD before the disease [becomes] serious,” related Suzanne Hurd, PhD, Scientific Director of GOLD and a member of the expert panel that developed the guidelines. A major barrier to early detection, she told RESPIRATORY REVIEWS, is the misperception that COPD is mainly a disease of the elderly—it can actually begin to develop well before old age.

ASSESSMENT AND MONITORING

To detect COPD early, practitioners should suspect the disease in any patient with chronic cough and sputum production and a history of COPD risk factors such as smoking, regardless of whether dyspnea is present. The diagnosis should be confirmed with spirometry, the guidelines state.

A postbronchodilator spirometric measurement of forced expiratory volume in one second (FEV1) less than 80% predicted and a ratio of FEV1 to forced vital capacity (FEV1/ FVC) below 70% suggest airflow limitation that is not fully reversible. “A decreased ratio is considered an early sign of COPD, even if the FEV1 is normal,” added Stephen I. Rennard, MD, another member of the expert panel and Chief of Pulmonary and Critical Care Medicine at the University of Nebraska in Omaha.

COPD is classified from stage 0 to stage III (Table 1). However, the disease is not static; COPD is likely to worsen over time, even with optimal care. Regular follow-up is therefore necessary to monitor lung function, symptoms, exacerbations, comorbidities, and the need for treatment regimen changes.

 

Table 1 GOLD Classification of COPD
Stage	Characteristics
0: At risk	Normal spirometry Chronic symptoms (cough, sputum production)
I: Mild COPD	FEV1/FVC ‹ 70% FEV1 greater than or equal to 80% predicted With or without chronic symptoms (cough, sputum production)
II: Moderate COPD	FEV1/FVC ‹ 70% FEV1 greater than or equal to 30% to ‹80% predicted IIa: FEV1 greater than or equal to 50% to ‹ 80% predicted IIb: FEV1 greater than or equal to 30% to ‹ 50% predicted With or without chronic symptoms (cough, sputum production, dyspnea)
III: Severe COPD	FEV1/FVC ‹ 70% FEV1 ‹ 30% predicted or FEV1 ‹ 50% predicted plus respiratory failure or clinical signs of right heart failure
GOLD, Global Initiative for Chronic Obstructive Lung Disease; COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in one second; FVC, forced vital capacity; respiratory failure, arterial partial pressure of oxygen ‹ 60 mm Hg with or without arterial partial pressure of carbon dioxide greater than or equal to 50 mm Hg while breathing air at sea level. Source: The GOLD Workshop Panel.[1]

Smoking cessation is the single most effective and cost-efficient intervention for reducing the risk of COPD and stopping its progression, according to the guidelines. “Even a brief, three-minute period of counseling to urge a smoker to quit can be effective, and at the very least this should be done for every smoker at every visit,” they stress.

REDUCING RISK FACTORS

The five-step program developed by the US Public Health Service provides a thorough approach to helping patients stop smoking.[2] The program emphasizes that physicians should assist patients with a quit plan, provide practical counseling, connect patients with sources of social support, offer various forms of pharmacotherapy when counseling alone is not enough, and include face-to-face or telephone follow-up.

Indoor and outdoor air pollution may worsen COPD, although its effect is thought to be small relative to that of smoking. High-risk COPD patients should avoid vigorous exercise outdoors when air-pollution levels are high and make sure they have adequate ventilation indoors when using solid fuels for cooking and heating, the guidelines advise. Patients with severe COPD should monitor public announcements of air quality and stay indoors when air quality is poor.

The risk of respiratory disease from occupational exposures remains unknown, both in developed and developing countries. Primary prevention is the optimal approach to such disease, and it requires reducing or eliminating exposure in the workplace to relevant toxic substances.

MANAGING STABLE DISEASE

For stable COPD, the overall management approach should be a stepwise increase in treatment based on an individualized assessment of disease severity and the response to different therapies. Patient education on smoking cessation, minimizing dyspnea, seeking medical attention, and other topics is also important because it can help improve quality of life.

Because existing medications cannot modify the progressive lung function decline associated with COPD, the goal of drug therapy is to ameliorate symptoms and/or decrease complications. The first-line agents for stable COPD are inhaled bronchodilators, such as ß2-agonists, anticholinergics, and methylxanthines.

These medications can be prescribed regularly or as needed to prevent or reduce symptoms. Combining those with different mechanisms and durations of action may increase bronchodilation without raising the risk of side effects, the guidelines state.

“Inhaled glucocorticoids may be useful in treating stable COPD, but not in all cases,” commented Dr. Rennard, who is also Larson Professor of Medicine at the University of Nebraska Medical Center. Indeed, regular treatment with inhaled glucocorticoids is appropriate only for two groups: symptomatic COPD patients with a documented spirometric response to these medications, and those who have an FEV1 less than 50% predicted and repeated exacerbations requiring antibiotics or oral glucocorticoids.

The guidelines recommend a six-week to three-month trial to identify COPD patients who may benefit from long-term inhaled glucocorticoids. In contradistinction, long-term oral glucocorticoids are not recommended because there is no proof of benefit. Moreover, they may cause steroid myopathy, which contributes to muscle weakness, decreased functional ability, and respiratory failure in patients with advanced COPD.

Exercise improves dyspnea, fatigue, and exercise tolerance; therefore it is a beneficial part of pulmonary rehabilitation for all COPD patients. Long-term oxygen administration (more than 15 hours daily) has been shown to increase survival in those with chronic respiratory failure.

MANAGING ACUTE EXACERBATIONS

According to the guidelines, COPD patients with acute exacerbations should be considered for hospital assessment and admission based on these criteria (which depend on local resources):

• Markedly increased symptom intensity (eg, sudden resting dyspnea).

• Severe underlying COPD.

• Onset of new physical signs, such as cyanosis or peripheral edema.

• Failure of the exacerbation to respond to initial medical management.

• Significant comorbidities.

• New arrhythmias.

• Diagnostic uncertainty.

• Advanced age.

• Insufficient support at home.

Indications for immediate intensive care unit (ICU) admission include confusion, lethargy, or coma, in addition to severe dyspnea that responds inadequately to initial emergency therapy. Acute exacerbations of COPD also require ICU management if the patient has persistent or worsening hypoxemia, severe or worsening hypercapnia, or severe or worsening respiratory acidosis despite supplemental oxygen and noninvasive positive pressure ventilation (NIPPV).

Controlled oxygen therapy is the cornerstone of treatment for acute exacerbations in the hospital. NIPPV is useful, too, because it improves blood gases and pH, reduces the length of hospital stay and mortality, and decreases the need for intubation and mechanical ventilation.

Short-acting inhaled ß2-agonists are the preferred bronchodilators for acute exacerbations. Inhaled anticholinergics, theophylline, and systemic glucocorticoids may also be administered in these cases.

Antibiotics are effective only in patients with worsening dyspnea and cough who also have increased sputum volume and purulence, the guidelines point out. The choice of agent should reflect local patterns of antibiotic sensitivity to Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.

Many aspects of COPD require further research to foster much needed improvement, such as assessment and monitoring techniques, national and worldwide surveillance, and primary prevention. One particularly important research area, however, is the molecular and cellular pathogenic mechanisms of COPD. “A better understanding of these is key and will lead to new therapeutic approaches,” Dr. Hurd said.

—Timothy Begany