CASE: Mr Dooby, a 52 year old male, presents to your office with a chronic cough and shortness of breath with normal activities, worsening over the last 12 months. By history, he has been a pack per day smoker since he was 18 years of age.
Does this patient have chronic obstructive pulmonary disease?
Chronic obstructive pulmonary disease (COPD) is a chronic respiratory disease characterized by chronic cough, shortness of breath with exertion or at rest. It is the 3rd leading cause of death in the United States affecting 4-9% of the population with up to 90% of COPD cases related to smoking. Diminished breath sounds, peak flow rates of under 350-l/min and a 30 pack year smoking history are 98% positively predictive. Diagnosis can be confirmed by spirometry with bronchodilators with an FEV1/FVC ratio of under 0.7 with increasing degrees of irreversibility (by bronchodilator). The GOLD classification is based on this latter index with the FEV1 % of predicted
> 80 mild
50-79 moderate
30-49 severe
< 30 very severe
The primary differential is with asthma which is characterized by reversibility and variability of airflow obstruction. Other conditions to consider include congestive heart failure, lung cancer, pulmonary arterial hypertension, interstitial lung disease and upper airway/ vocal cord dysfunctions.
The foundations of management include smoking cessation through tobacco cessation programs and pharmacotherapy with nicotine replacement, varnenicline, or buproprion. Also includes regular use of inhaled bronchodilators starting with short acting beta agonists or anticholinergics for mild COPD with addition of long acting beta agonist (LABA) or long acting anticholingerics. With progression of disease severity, additional of an inhaled corticosteroid in combination with a LABA is indicated. Roflumilast (Daliresp) which is a phosphodiesterase-4 inhibitor should also be considered in severe or very severe COPD.
The role of oxygen has evolved with recommendations now to provide supplemental oxygen to patients with COPD who have severe resting hypoxia (O2 sat 88% or less). The key is to ensure that patients use oxygen for at least 15 hours per day to achieve target O2 saturations of 88-92%. Pulmonary rehab is also important for severe-very severe COPD patients. Mucolytics and anti-tussives are NOT recommended and provide little benefit.
As the disease progresses, consider providing or referring for palliative care. Use of the BODE Index allows you to determine the risk of dying in your COPD patients. BODE includes four variables: FEV1, six minute walk distance, MRC dyspnea score, and BMI. Scores indicate four year survival rates with 0-2 = 80% survival up to 7-10 18% survival.