Chronic obstructive lung disease (COPD) is the third leading cause of death in the United States1 and a major cause of mortality and morbidity around the world. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) released a new “2017 Report”2 with modified recommendations for the diagnosis, management, and prevention of COPD. The report contains several changes that are relevant to the primary care provider that will be outlined below.
Redefining COPD
GOLD’s definition of COPD was changed in its 2017 Report: “COPD is a common, preventable, and treatable disease that is characterized by persistent respiratory symptoms and airflow limitations that are due to airway and/or alveolar abnormalities usually caused by significant exposure to noxious particles or gases.” The report emphasizes that “COPD may be punctuated by periods of acute worsening of respiratory symptoms, called exacerbations.” Note that the terms “emphysema” and “chronic bronchitis” have been removed in favor of a more comprehensive description of the pathophysiology of COPD. Importantly, the report states that cough and sputum production for at least 3 months in each of 2 consecutive years, previously accepted as diagnostic criteria, are present in only a minority of patients. It is noted that chronic respiratory symptoms may exist without spirometric changes and many patients (usually smokers) have structural evidence of COPD without airflow limitation.
Changes to COPD initial assessment
The primary criterion for diagnosis is unchanged: post-bronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) less than 0.70. Spirometry remains important to confirm the diagnosis in those with classic symptoms of dyspnea, chronic cough, and/or sputum production with a history of exposure to noxious particles or gases.
The GOLD assessment system previously incorporated spirometry and included an “ABCD” system such that patients in group A are least severe. Spirometry has been progressively deemphasized in favor of symptom-based classification and the 2017 Report, for the first time, dissociates spirometric findings from severity classification.
The new system uses symptom severity and exacerbation risk to classify COPD. Two specific standardized COPD symptom measurement tools, The Modified British Medical Research Council (mMRC) questionnaire and COPD Assessment Test (CAT), are reported by GOLD as the most widely used. Low symptom severity is considered an mMRC less than or equal to 1 or CAT less than or equal to 9, high symptom severity is considered an mMRC greater than or equal to 2 or CAT greater than or equal to 10. Low risk of exacerbation is defined as no more than one exacerbation not resulting in hospital admission in the last 12 months; high risk of exacerbation is defined as at least two exacerbations or any exacerbations resulting in hospital admission in the last 12 months. Symptom severity and exacerbation risk is divided into four quadrants:
• GOLD group A: Low symptom severity, low exacerbation risk.
• GOLD group B: High symptom severity, low exacerbation risk.
• GOLD group C: Low symptom severity, high exacerbation risk.
• GOLD group D: High symptom severity, high exacerbation risk.
Changes to prevention and management of stable COPD
Smoking cessation remains important in the prevention of COPD. The 2017 Report reflects the U.S. Preventive Services Task Force’s guidelines for smoking cessation: Offer nicotine replacement, cessation counseling, and pharmacotherapy (varenicline, bupropion or nortriptyline). There is insufficient evidence to support the use of e-cigarettes. Influenza and pneumococcal vaccinations are recommended. Pulmonary rehabilitation remains important.
The 2017 Report includes an expanded discussion of COPD medications. The role of short-acting bronchodilators (SABD) in COPD remains prominent. Changes include a stronger recommendation to use combination short-acting beta-agonists and short-acting muscarinic antagonists (SABA/SAMA) as these seem to be superior to SABD monotherapy in improving symptoms and FEV1.
There were several changes to the pharmacologic treatment algorithm. For the first time, GOLD proposes escalation strategies. Preference is given to LABA/LAMA (long-acting beta-agonist/long-acting muscarinic antagonists) combinations over LABA/ICS (long-acting beta-agonist/inhaled corticosteroid) combinations as a mainstay of treatment. The rationale for this change is that LABA/LAMAs give greater bronchodilation compared with LABA/ICS, and one study showed a decreased rate of exacerbations compared to LABA/ICS in patients with a history of exacerbations. In addition, patients with COPD who receive ICS appear to have a higher risk of developing pneumonia. GOLD recommendations are:
• Group A: Start with single bronchodilator (short- or long-acting), escalate to alternative class of bronchodilator if necessary.
• Group B: Start with LABA or LAMA, escalate to LABA/LAMA if symptoms persist.
• Group C: Start with LAMA, escalate to LABA/LAMA (preferred) or LABA/ICS if exacerbations continue.
• Group D: Start with LABA/LAMA (preferred) or LAMA monotherapy, escalate to LABA/LAMA/ICS (preferred) or try LABA/ICS before escalating to LAMA/LABA/ICS if symptoms persist or exacerbations continue; roflumilast and/or a macrolide may be considered if further exacerbations occur with LABA/LAMA/ICS.
Bottom line
1. GOLD classification of COPD severity is now based on clinical criteria alone: symptom assessment and risk for exacerbation.
2. SABA/SAMA combination therapy seems to be superior to either SABA or SAMA alone.
3. Patients in group A (milder symptoms, low exacerbation risk) may be initiated on either short- or long-acting bronchodilator therapy.
4. Patients in group B (milder symptoms, increased exacerbation risk) should be initiated on LAMA monotherapy.
5. LABA/LAMA combination therapy seems to be superior to LABA/ICS combination therapy and should be used when long-acting bronchodilator monotherapy fails to control symptoms or reduce exacerbations.
References
1. CDC MMWR 11/23/12
2. Global Strategy for the Diagnosis, Management and Prevention of COPD, Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017 at http://goldcopd.org (accessed 3/10/2017)
Dr. Skolnik is associate director of the family medicine residency program at Abington (Pa.) Memorial Hospital. Dr. Lent is chief resident in the program.
