Practice recommendations
- Perform spirometric testing on any patient who complains of difficulty breathing and has a history of smoking or risk factors for chronic obstructive pulmonary disease (COPD) (American College of Physicians grade: Strong recommendation, moderate-quality evidence)
- Use inhaled bronchodilators and oral glucocorticosteroids for COPD exacerbations (Global Initiative for Chronic Obstructive Lung Disease [GOLD] Evidence A)
- Use antibiotics for COPD exacerbations (GOLD Evidence B)
- Use long-acting beta-agonists, long-acting anticholinergics, or inhaled steroids for chronic, stable COPD (American College of Physicians grade: Strong recommendation, high-quality evidence)
- Smoking cessation is the most effective way to decrease the risk of COPD progression (GOLD Evidence A)
GOLD Evidence categories
- Randomized controlled trials (RCTs); rich body of data
- RCTs; limited body of data
- Nonrandomized trials; observational studies
- Panel consensus judgment
A new patient comes into your office and tells you he experiences labored breathing on exertion, smokes a pack of cigarettes a day, and has a smoker’s cough.
- Would you perform spirometry to gauge airway obstruction?
- How do you think your decision would compare with those of your colleagues?
In this article, we put your answer into context by revealing just how underutilized spirometry is.
We also use a progressive case example to illustrate evidence-based recommendations and management tips for chronic obstructive pulmonary disease (COPD) and address often overlooked gaps in care.
Many of the recommendations in this article come from the Global Initiative for Chronic Obstructive Lung Disease (GOLD), published in the American Journal of Respiratory and Critical Care Medicine1 and updated online at www.goldcopd.org. (This initiative, begun in 1998, provides specific, evidence-based guidelines on the prevention, assessment, and management of COPD patients.) We also refer to newly published American College of Physicians (ACP) evidence-based guidelines for managing chronic, stable COPD.2,3
CASE: Shortness of breath, smoker’s cough
Mr. Jones, a 57-year-old patient in our practice, says that for the past 3 months he has increasingly experienced shortness of breath when walking up a flight of stairs. He has smoked cigarettes for many years and also acknowledges having a smoker’s cough. He brings up clear phlegm on most days.
Dyspnea is the most common symptom reported by patients with COPD. In a study of 2678 patients, the first and most troublesome symptom noted was dyspnea (71%), followed by cough (19%).4 Patients typically say their dyspnea has worsened over time. It tends to occur daily, particularly with exercise. Cough may be intermittent and nonproductive.
Consider the diagnosis whenever a patient with dyspnea has a risk factor for COPD, such as smoking (~80% of cases); extended second-hand smoke exposure; contact with occupational dust, home cooking and heating fuels, or other potentially toxic chemicals; or has a history of recurrent lung infections.5 With patients in their 30s or 40s exhibiting signs and symptoms suggestive of COPD, consider a work-up for alpha-1 antitrypsin deficiency. (See “Does your patient have alpha-1 antitrypsin deficiency?”.)
Physical examination has limited usefulness. It exhibits poor sensitivity for detecting mild-to-moderate COPD, unless wheezing is present. Wheezing in smokers (more than 40 pack-years) has a positive likelihood ratio of 8.3 for obstructive airway disease.6
Physical diagnosis is easier with more severe disease, especially if patients show classic signs of COPD, such as pursed-lip breathing, decreased breath sounds, and prolonged expiratory wheezes.
Spirometry is key, and underused. Demonstrating airflow obstruction on spirometry is essential to a COPD diagnosis. An FEV1/FVC ratio <0.70 or FEV1 <80% in patients who have received a test-bronchodilator confirms airflow obstruction.
Amazingly, a COPD diagnosis is assigned to less than half of the estimated 24 million patients with airflow obstruction in United States,7 despite the fact that COPD is the 4th leading cause of death, and the 12th leading cause of morbidity.1 Most of those who are identified have advanced disease.8 This dramatic underdiagnosis is attributable to the underuse of office spirometry as a diagnostic tool.9
A Canadian study revealed that only 21% of physicians ordered spirometry when managing a middle-aged smoker with cough.10,11 Another study showed that only 22% of North American physicians would order spirometry for a smoker with cough.10,12 Only a third of patients had undergone spirometry within 2 years of a new diagnosis of COPD. The lowest frequency of testing was among elderly patients, especially among those older than 75 years.10 (Caveat: as patients age, FEV1 naturally declines, making it easy to overdiagnose airflow obstruction in elderly patients.8,13)
The above data regarding underuse of spirometry apply to symptomatic patients. A recent US Preventive Services Task Force analysis found that screening asymptomatic smokers does not improve health outcomes; the number needed to test with spirometry would be in the “hundreds” to defer a single exacerbation.9 (ACP grade: strong recommendation, moderate-quality evidence.)