Treating stable COPD
By Samy El-Halawani, DO
The purpose of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines is to provide a non-biased review of the current evidence for the assessment, diagnosis, and treatment of patients with chronic obstructive pulmonary disease (COPD). They also highlight short-term and long-term treatment objectives: relieving and reducing the impact of symptoms, and reducing the risk of adverse health events that may affect the patient in the future. Finally, they are designed to guide symptom assessment and health status measurement. GOLD defines COPD as “a common, preventable, and treatable disease that is characterized by persistent respiratory symptoms and airflow limitation that is due to airway and/or alveolar abnormalities usually caused by significant exposure to noxious particles or gases.”
An ABCD grading system (see Figure 1) was originally introduced by GOLD in 2011. In earlier published versions of the guidelines, the grading system was based on the severity of airflow obstruction (FEV1 measured by spirometry). FEV1, however, does not predict breathlessness, functional limitation, or the impact of COPD on the patient’s quality of life as effectively as the patient-reported symptoms and prior history of COPD exacerbations. Therefore, the 2011 ABCD grading system took into account symptom severity and exacerbations per year in addition to the severity of airflow limitation.
The GOLD COPD severity grading system continues to evolve, and a revised version was released in 2017. Modifications were made because the ABCD assessment tool performed no better than the spirometric grades for multiple important COPD outcomes, including mortality. Additionally, the most severe group (group D) could be defined by lung function and/ or patient history, which led to confusion. The updated 2017 version now suggests using an assessment of the spirometric grades in parallel with a combined assessment of an individual’s symptoms and exacerbation history to guide therapy (see Figure 2).
GOLD recommends either the modified British Medical Research Council (mMRC) questionnaire (scaled 0–4) or the COPD Assessment Test (CAT) (scaled 0–40) for symptom assessment. The GOLD authors then chose questionnaire scoring cut-offs to separate patients with higher symptom burden from those with lower burden. Finally, two or more mild or moderate exacerbations or a COPD exacerbation-related hospitalization in the preceding year were used to indicate patients who were high risk for recurrent exacerbations.
The importance of spirometry
Despite the separation of spirometric grades from the ABCD severity groups, the importance of spirometry in the diagnosis and management of COPD cannot be understated. The GOLD criteria (FEV1/FVC < 0.7) performs well for the diagnosis of COPD in Americans 65 years or older who have respiratory symptoms and risk factors for COPD (i.e., current or previous smokers). In older, healthy, non-smokers, however, it can lead to overdiagnosis (Hardie et al., European Respiratory Journal, 2002).
Spirometry should be performed on anyone with risk factors and symptoms of COPD. COPD is markedly underdiagnosed, with recent estimates of between 25 and 50 percent of patients with clinically important disease being undetected or misdiagnosed (GOLD Report, 2017). In the primary care setting, the wrong diagnosis can be common. Some patients who have a clinical diagnosis of COPD are found to have normal lung function (approximately 25 percent of smokers get COPD [Løoke, Thorax, 2006]), while many patients with COPD are undiagnosed. As previously stated, a post-bronchodilator FEV1/FVC < 0.7 is necessary for the diagnosis of COPD based on the GOLD group’s definition, however the specific criteria may differ based on the source that is consulted. It is also important to recognize that the airflow obstruction in COPD is fixed and not completely reversible with bronchodilators, leading to the recommendation that the post-bronchodilator FEV1/FVC value is used.
Pharmacologic therapy for COPD is prescribed to reduce the severity and frequency of exacerbations, relieve symptoms of breathlessness, improve exercise tolerance, and improve health status. There are no data that inhaled therapy reduces decline in lung function (smoking cessation does) or decreases mortality. A number of classes of medications are commonly used to treat COPD. Based on the ABCD grading system, an algorithm for the pharmacologic treatment of COPD can be devised that includes initial treatment and escalation therapy.
Inhaled corticosteroids have no effect on mortality or decline in lung function. They can improve airway reactivity and respiratory symptoms, as well as decrease the use of health care services for respiratory problems (Lung Health Study Research Group, 2000). These benefits should be weighed against the increased risk of serious pneumonia. Corticosteroid monotherapy should be avoided in COPD, and its use should be in combination with bronchodilators. The purpose of bronchodilators is to improve symptoms, FEV1 (lung function), and reduce exacerbations. Like inhaled corticosteroids, they do not reduce mortality. Long-acting beta agonists (LABAs) and long-acting muscarinic antagonists (LAMAs) are preferred over the use of short-acting beta agonists (SABAs). SABA use on a regularly scheduled basis is generally not recommended. The use of LABAs alone continues to raise concern in practice, yet the mortality issues seen with LABA monotherapy in asthma are not present in COPD. Patients with frequent exacerbations can be given a trial of daily azithromycin or Roflumilast.
A 68-year-old male with a 50 pk/yr smoking history presents with one year of worsening dyspnea on exertion and a troublesome morning cough. He can walk approximately 1.5 blocks before he has to stop to catch his breath. He has never been admitted to the hospital for respiratory issues and has never had prednisone as an outpatient. The COPD assessment test is administered, and he scores 26. This patient would be labeled GOLD grade 2, Group B (see Figures 1 and 2). First-line therapy in this case could include a LAMA or LABA in addition to non-pharmacologic therapy.
Initial non-pharmacologic treatment
Non-pharmacologic therapy should be combined with pharmacologic therapy in all patients with COPD. Smoking cessation remains critical and, as previously mentioned, can reduce the rate of decline in lung function. Vaccinations can reduce infections and exacerbations. An annual influenza vaccine should be given to all patients. The PPSV23 is advised for patients with COPD under the age of 65 with comorbid conditions. Both the PCV13 and PPSV23 are recommended for patients 65 years of age and older. Participation in pulmonary rehabilitation programs improves dyspnea, health status, exercise tolerance, and, in patients who have had a recent exacerbation, hospitalizations can be reduced. Long-term oxygen therapy (> 15 hrs/day) can reduce mortality in selected patients with COPD.
The newly updated GOLD guidelines recommend using patient symptoms (mMRC or CAT) and frequency of exacerbations to guide therapy. Although spirometry remains vital in establishing the diagnosis of COPD (FEV1/FVC < 0.7), FEV1 values are no longer included in the ABCD grading system. Beta2-agonists, antimuscarinic drugs, and inhaled corticosteroids in combination with long-acting bronchodilators are the classes of medications commonly used to treat COPD. The 2017 Global Strategy for the Diagnosis, Management, and Prevention of COPD is available at www.goldcopd.org.
Samy El-Halawani, DO, is with Allina Health United Lung and Sleep Clinic. He is board-certified in critical care, osteopathy, pulmonary and internal medicine, and sees patients in St. Paul and at the Apple Valley Medical Center.