Dx/Mgmt Chronic COPD

Posted on Jun 28, 2011 in Articles | 1 comment

Improving Patient Outcomes: A Guidelines-based Approach to the Diagnosis and Management of Chronic Obstructive Pulmonary Disease

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Learning Objectives

After participating in this educational activity, participants should be better able to

• Implement evidence-based recommendations for the accurate diagnosis and appropriate management of patients with chronic obstructive pulmonary disease based on established clinical guidelines
• Develop treatment plans that incorporate individual patient’s needs, preferences, and lifestyle to optimize patient adherence

 

Introduction

Chronic obstructive pulmonary disease (COPD) is a debilitating disease that affects millions of Americans and may go unrecognized and underdiagnosed.[1-3] Overall, approximately 10% of people 40 years and older have moderately severe airflow obstruction measured by spirometry.[4] In 2007, about 12 million Americans were diagnosed with COPD, but an additional 12 million may have had COPD that was undiagnosed.[5] COPD also remains a leading cause of death in the United States following heart disease, cancer, and stroke.[5] A recent study reported that 44% of patients (N=615) were not treated according to the Global Initiative for Chronic Obstructive Lung Disease’s Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease (GOLD guidelines) criteria.[6] This activity will provide practicing clinicians with an understanding of how to accurately diagnose COPD and categorize its severity, an overview of currently available guideline-recommended pharmacologic and nonpharmacologic treatment options for COPD, and management strategies that address recommended adherence to inhaled medications.

COPD Characteristics and Risk Factors

COPD is a progressive syndrome of expiratory airflow limitation caused by chronic inflammation of the airways and destruction of lung parenchyma.[7] The two major forms of COPD, as described in the GOLD guidelines, are chronic bronchitis and emphysema. The airflow limitation of COPD is usually progressive and not fully reversible.[7] The GOLD guidelines state that the pathophysiology of COPD involves an abnormal inflammatory response of the lungs to noxious particles or gases.[7] Damage to the central and peripheral airways and the lung parenchyma result in physiologic abnormalities, specifically airway obstruction which can lead to clinical symptoms and exacerbations.

Risk factors for COPD include prolonged exposure to tobacco smoke (>20 pack-years) and being older than 40. When discussing tobacco use with a patient, it is important to note that many smokers underreport their smoking history.[8] Ninety percent of all long-term smokers started smoking at or before the age of 20; therefore, it is likely that patients have been smoking longer than they have indicated. In general, onset of COPD is during midlife in patients with a strong smoking history and exertional dyspnea. Patients typically have slowly progressing symptoms and airflow obstruction becomes irreversible over time. Respiratory symptoms including productive cough, wheezing, and dyspnea are common in COPD. A recent study found that productive cough, wheeze, or dyspnea was present in 92% of subjects who smoked and had obstruction, but these symptoms alone are not indicative of a diagnosis of COPD.[2]

Diagnosing COPD

First and foremost is the need to carefully interview a patient suspected of having COPD. As a part of the patient’s history, it is important for the clinician to learn more about the patient’s smoking habit and duration, exposure to environmental/occupational hazards, and past history of atopy/sinusitis/respiratory disease. Understanding the type and pattern of the patient’s recent symptom development and history of any exacerbations, or COPD-related hospitalizations, is an essential component of the history. Comorbid disorders are common in COPD. Having the patient describe how recent symptoms impact his or her quality of life (QOL) is an important basis for planning therapeutic interventions. Exploring the family history for COPD or other respiratory diseases may provide clues as to unusual causes of COPD.[7]

Assessing Breathlessness

A diagnosis of COPD should be suspected in patients presenting with chronic cough, sputum production, or exertional dyspnea, especially if there is a significant smoking history.[9] An important component of this part of a patient’s history is reviewing complaints of breathlessness on exertion. The Modified Medical Research Council (MMRC) Dyspnea Scale is a simple, validated tool that can be used to assess the severity of the complaint of breathlessness or dyspnea (Table 1).[10] Since symptoms alone are not adequate to confirm a diagnosis of COPD in all patients, there is a need for objective tests, such as spirometry, to confirm the diagnosis.

Confirming a Diagnosis of COPD With Spirometry

It is important to understand that symptoms can lead the healthcare provider to suspect the diagnosis of COPD, but objective testing is required to confirm the presence of airflow obstruction. The definition of COPD requires that airway obstruction be confirmed in those suspected of having the disease.[7] Spirometry is the test most commonly used to evaluate patients for airflow limitation. The American College of Chest Physicians recommends that symptomatic patients undergo spirometry.[11] Although the diagnosis of COPD should be strongly considered in current smokers older than 40 with a 20 pack-year smoking history and respiratory symptoms of cough and breathlessness on exertion, this clinical scenario is not sufficient to establish an accurate diagnosis of COPD.[2] In these patients, it is strongly recommended that spirometry be performed to confirm a diagnosis of COPD.

Spirometry is a useful test to measure the forced expiratory volume in one second (FEV1; percentage of predicted value), forced vital capacity (FVC; percentage of predicted value), and the FEV1/FVC ratio. In patients with suspected COPD, spirometry should be performed before (pre-) and after (post-) administration of an inhaled short-acting bronchodilator. A post-bronchodilator FEV1/FVC ratio of <70% is consistent with airway obstruction.[7] The severity of airway obstruction is quantified based on post-bronchodilator FEV1 values (Table 2).

Stage I or mild COPD is characterized by an FEV1 of  ≥80% of predicted and an FEV1/FVC ratio that is <70%, indicative of airflow obstruction. In Stage II or moderate COPD, FEV1 is <80% and ≥50% of predicted. Stage III or severe COPD is characterized by an FEV1 <50% and  ≥30% of predicted. Individuals with an FEV1 <30% of predicted or FEV1 <50% of predicted with chronic respiratory failure are classified as Stage IV or very severe COPD. The use of spirometry for appropriate classification of disease stage is important, as it guides therapy as well as prognosis.

If spirometry is not available, peak flow measures can sometimes be used to support the presence of airflow obstruction; however, if objective measures of airflow limitation are not available, it is imperative to take an accurate smoking history and assessment of respiratory symptoms. Especially helpful is determining how a patient’s activities may have changed over recent months. Does the patient get short of breath climbing stairs or walking? Has the patient been forced to limit his activities because of concerns about becoming short of breath? What is the patient unable to do now, in terms of daily activities of life, which he was able to do in the recent past? This information, as well as additional details such as coughing and sputum production, will provide the clinician with the knowledge to make a clinical assessment toward an accurate diagnosis of COPD.

Differential Diagnosis and Other Tests

Considerations for a differential diagnosis should be given to conditions such as asthma, pneumonia, bronchiectasis, congestive heart failure, diffuse panbronchiolitis, obliterative bronchiolitis, pulmonary hypertension, or tuberculosis if a clear diagnosis of COPD cannot be made.[7] Asthma is the disease that is most often confused with COPD, but asthma typically has an onset in childhood and is also associated with a history of other atopic diseases, such as eczema and allergic rhinitis. Asthma symptoms are more variable both throughout the day and over weeks and months. COPD tends to be a chronic, progressive disease first presenting in middle-age or older patients. Also, patients with asthma generally have airway obstruction that is mostly reversible by treatment with a bronchodilator. A chest radiograph or computed tomography (CT) scan is not routinely recommended for establishing a diagnosis of COPD, but can aid in the exclusion of other conditions if suspected.[7] Alpha-1 antitrypsin screening may be considered if the patient has suspected COPD with onset before age 45 and a strong family history.[7] An alpha-1 antitrypsin concentration that is 15% to 20% normal is highly indicative of a genetic deficiency. Arterial blood gas measurement in stable patients with FEV1 less than 50% still breathing air is important to monitor for respiratory failure or right heart failure, but not necessarily recommended to confirm a diagnosis.[7]

Guideline-based Management of COPD

There are four components of COPD management: 1) assessment and monitoring of disease, 2) reduction of risk factors, 3) management of stable COPD, which includes education and nonpharmacologic and pharmacologic therapies, and 4) management of exacerbations. The GOLD guidelines outline COPD management strategies that were updated in 2010 and are described here.[7] For the purposes of this activity, focus is given on the care of patients with stable COPD. Strategies to manage acute episodes, or exacerbations, can be found in the GOLD guidelines.

Once severity is assessed, the next step in caring for a patient with COPD is to address risk factors. Encouraging smoking cessation is imperative to preventing further decline in lung function. One model to address this issue is the 5 A’s (Table 3).[12] In this model, patients are asked about their tobacco use, advised to quit, assessed for their willingness to quit, assisted in their attempt to quit, and provided follow-up to monitor their progress toward quitting. Further assistance in the effort to quit at follow-up visits may be necessary until the patient is prepared and willing to take action.

Pharmacotherapy for COPD

As a first course of action, consideration for appropriate vaccines should be made for patients with COPD. It has been shown that influenza vaccines reduce serious illness and death by about 50% in patients with COPD. Either killed or live inactivated virus is recommended seasonally.[7] Pneumococcal polysaccharide vaccine is recommended in adults ages 19 through 64 who smoke cigarettes and in all patients 65 years or older.[7,13] Pneumococcal polysaccharide vaccine has been shown to reduce community acquired pneumonia in patients younger than 65 years with FEV1 <40% predicted.[7]

In Figure 1, the recommended approach to treatment based on COPD severity is shown from the GOLD guidelines.[7]

Bronchodilators are central to the symptomatic management of COPD on an as-needed or regular basis to prevent or reduce symptoms and exacerbations (Table 4).[7] The principal bronchodilator treatments are β2-agonists, anticholinergics, and methylxanthines used singly or in combination.[7]

Short-acting bronchodilators as needed are the recommended treatment for patients with mild or Stage I COPD, whereas scheduled long-acting bronchodilators are recommended for those with moderate or Stage II disease and higher.[7] Theophylline is an effective bronchodilator for COPD and has been shown to reduce COPD exacerbations but inhaled bronchodilators are preferred due to faster onset of action and lower incidence of side effects. Side effects are typically caffeine-like in nature and can include headache, nausea, diarrhea, trouble sleeping, temporary changes in behavior, restlessness, and temporary increased urination.[14] For patients with Stage II COPD and higher, regular treatment with the long-acting anticholinergic tiotropium or long-acting β2-agonists (LABAs) is more effective and convenient than treatment with short-acting bronchodilators (albuterol and/or ipratropium).[7] Side effects for ipratropium include cough, dizziness, dry mouth, dry nose or nose irritation, flu-like symptoms, headache, nausea, nervousness, pain, upper respiratory tract infection, runny nose, sinus infection, and sore throat.[15] Side effects for tiotropium include upper respiratory tract infection, dry mouth, sinusitis, pharyngitis, nonspecific chest pain, urinary tract infection, dyspepsia, and rhinitis.[16] Side effects with any β2-agonist may include angina, arrhythmias, dizziness, fatigue, headache, hypertension or hypotension, nervousness, tremor, dry mouth, muscle cramps, palpitations, nausea, malaise, insomnia, hypokalemia, hyperglycemia, tachycardia, and metabolic acidosis (product package inserts for approved β2-agonists). In general, LABAs such as formoterol and salmeterol have 12-hour durations of action and can be administered as either nebulized or dry powder formulations.

For patients with severe or Stage III disease and higher, combination therapy with bronchodilators with different mechanisms of action or the addition of corticosteroids if patients are experiencing repeated exacerbations may be appropriate. Reported side effects of oral or inhaled corticosteroids include difficulty sleeping, feeling of a whirling motion, increased appetite, increased sweating, indigestion, mood changes, nervousness, nosebleed, back problems, bronchitis, cough, diarrhea, difficulty speaking, dry mouth, fever, flu, headache, hoarseness, muscle pain, nausea, oral yeast infection, sinus inflammation, sore throat, stomach pain or discomfort, runny or stuffy nose, throat irritation, upper respiratory tract infection.[17-19] The combined use of LABAs and anticholinergics has complementary benefits and the use of one or more long-acting agents may be important for the maintenance therapy of COPD. The availability of longer acting and more potent bronchodilators, as well as newer combinations, has offered additional options for the treatment of COPD.[20] For example, in an active-controlled, double-blind, 12-week multicenter trial of 255 patients with COPD, the addition of inhaled formoterol to tiotropium significantly improved FEV1 versus tiotropium alone.[21] Additionally, significantly greater reductions in symptom scores (P<.05) and daytime albuterol use (P<.04) were observed for the combination versus tiotropium alone.[21] Similarly, the addition of arformoterol to tiotropium provides increased benefit over either therapy alone.[22] Importantly, a comparable observation was made for the nebulized version of formoterol when added to tiotropium maintenance therapy for patients with moderate to severe COPD. The results of two double-blind studies demonstrated that FEV1 over three hours was significantly higher with combination therapy of nebulized formoterol plus tiotropium versus tiotropium alone.[23] Albuterol use also declined with combination therapy (2.6 to 1.5 puffs/day) compared with little change in the tiotropium only group (P<.0001). More patients receiving tiotropium alone experienced COPD exacerbations (7.9% vs 3.4%). As these studies demonstrate, the use of combination therapy may yield more favorable long-term benefits.

For very severe COPD or Stage IV disease, long-term oxygen use may be necessary if chronic respiratory failure is present and surgery may be considered.[7] The addition of regular treatment with an inhaled corticosteroid (ICS) to bronchodilator therapy may be appropriate for symptomatic COPD patients with an FEV1 <50% predicted (severe and very severe COPD) and repeated exacerbations.[7] The Towards a Revolution in COPD Health (TORCH) study showed that combination therapy with fluticasone/salmeterol reduced exacerbations and improved other outcomes; however, it did not demonstrate a survival benefit.[24] A post hoc analysis of this study demonstrated that combination therapy reduced moderate-to-severe exacerbations and improved health status and FEV1 across all GOLD stages of COPD. Additionally, treatment with an ICS/LABA combination may be associated with reduced mortality compared with placebo in patients with GOLD Stage II COPD.[25]

Nonpharmacologic Therapy for COPD

Common problems that can affect patients with Stage II COPD or higher include exercise deconditioning, social isolation, depression, muscle wasting, and weight loss. Pulmonary rehabilitation has been shown to improve exercise capacity and arm function, patient QOL, and survival, and reduces hospitalizations as well as anxiety and depression.[7] Although there is no formal recommendation for pulmonary rehabilitation for any given patient type; exercise training, nutrition counseling, and education appear to benefit COPD patients of all stages and should be routinely implemented in the overall management plan to improve patient QOL. Oxygen therapy is one of the principal treatments for patients with Stage IV, or very severe, COPD and can be administered as long-term therapy, during exercise, or for acute relief.[7] Long-term oxygen is initiated in patients with waking PaO2 (partial pressure of oxygen in arterial blood) at or below 7.3 kPa (kilopascal) (55 mm Hg) or SaO2 (oxygen saturation) at or below 88% with or without hypercapnia.[7] Long-term oxygen therapy may also be given to patients with waking PaO2 between 7.3 and 8.0 kPa or SaO2 of 88% if there is evidence of pulmonary hypertension, peripheral edema suggesting congestive heart failure, or polycythemia.[7] The oxygen delivered will be on an individual case-by-case basis. Additional measures may be necessary including surgery or ventilation support as the disease progresses.

Ongoing Monitoring

There are several strategies to ensure that patients receive adequate follow-up during their treatment. The following items are recommended by the GOLD guidelines for frequent monitoring[7]:

1. Exposure to risk factors (eg, smoking cessation progress, environmental exposures, and occupational dust or fumes)
2. Disease progression and development of complications (eg, pulmonary function, exercise testing, sleep quality, and signs of respiratory failure)
3. Pharmacotherapy and concomitant medications (eg, device technique, symptom control, side effects, and drug-drug interactions)
4. Acute episodes of COPD (exacerbation history)
5. Comorbidities (eg, cardiovascular disease, depression, and osteoporosis)

Frequency of visits will increase in patients with COPD and ongoing assessment can ensure that management goals are achieved. Comorbidities are common in COPD from the disease itself or the aging process and should be monitored regularly. Focus should be given to the prompt treatment of comorbidities to maintain QOL in patients with COPD.

Case Study: Alice, 53-year-old Female Patient With COPD

History

Alice is 53 years old and has been smoking one pack of cigarettes a day since the age of 18 (35 pack-years). Smoking for her has been a way to maintain a low weight. She has no history of allergies or other atopic conditions. None of her immediate family members have been diagnosed with COPD or had diagnoses for other obstructive respiratory diseases. Her parents were nonsmokers. She describes reduced mobility and tenderness in her right hand that has persisted following a car accident three years ago. She takes either ibuprofen or naproxen as needed for inflammation and pain. She has recently been getting short of breath while walking, climbing stairs, or performing other activities during the day and has become generally more nervous about her health.

Physical Exam

The following are the details of her physical examination which reveal wheezing and diminution of breath sounds and other clinical attributes that are within normal limits. Her weight and BMI are noted for reference at the next follow-up since they are approaching the low end of the normal curve.

• Height: 5’4”
• Weight: 120 lb
• Body mass index: 21
• Blood pressure: 145/82
• Heart rate: 80
• Respiratory rate: 22
• Heart: Regular rhythm and rate. No murmurs or gallops
• Lungs: Some wheezing on expiration and slight diminution in breath sounds
• HEENT: Normal
• Neck: No jugular venous distention

Alice’s MMRC dyspnea scale score is two which indicates that she has moderate exertional breathlessness compared with age-matched normals. Alpha-1 antitrypsin testing is not recommended for Alice based on her age and the absence of a family history for alpha-1 antitrypsin deficiency or respiratory diseases, including COPD. Her oxygen saturation is 97%.

Spirometry

Alice’s lung function tests are shown in Table 5. One source for predicted values of most spirometric parameters can be found at the Johns Hopkins Pulmonary Function Laboratory. Alice has a post-bronchodilator FEV1 of 1.37 liters, which is 65% of what is predicted for her age and height. Her post-bronchodilator FVC is 1.97 liters which is 75% of what is predicted for her age and height. This yields a post-bronchodilator FEV1/FVC ratio <0.70. A comparison of a normal versus typical patient with mild-to-moderate COPD is shown in Figure 2.[7] Alice’s spirometric results suggest that she has irreversible airway obstruction with moderate severity or Stage II COPD.

Diagnosis and Treatment

Alice is diagnosed with Stage II COPD. She is encouraged to begin a smoking cessation program and is provided educational information on available strategies. Pulmonary rehabilitation is recommended and will include an initial exercise test and then a consultation to develop both a nutrition and regular exercise plan.

She is administered both an influenza and pneumococcal vaccine in the office. Based on the GOLD guidelines, her clinician prescribed a SABA for the immediate relief of her symptoms when they occur. After determining that Alice’s hand dysfunction may interfere with the accurate and reliable administration of her medicine, the clinician prescribes a LABA by nebulizer to be given twice daily.

Planned Follow-up

A follow-up visit is scheduled for 30 days to reassess symptom frequency and control, to determine whether her smoking cessation plan worked, and to determine whether her management plan has had an impact on her daily activities and QOL. Adjustments to her plan will be made if necessary at that time.

Considerations for Patient Education and Medication Adherence

Patient education is also an integral part of a comprehensive COPD management plan (Table 6); it is important to reducing modifiable risk factors in any patient with a diagnosis of COPD.[7] Recommendations are to educate patients on COPD in general, provide training on their medication delivery devices, inform them about recognizing the frequency of their symptoms and preventing exacerbations, give strategies that minimize shortness of breath including exercise and pulmonary rehabilitation, and give information on disease and medication complications.

Inhaled medications can be delivered by several different devices including metered-dose inhalers (MDIs), dry powdered inhalers (DPIs), and nebulizers. It is estimated that between 28% and 68% of patients do not use MDIs or DPIs correctly.[26] For example, the use of an MDI may include up to nine steps. However, patients with COPD are diverse and represent a population with distinct characteristics such as lung function, comorbidities, cognitive functions, hand strength (ie, arthritis), and lifestyle.[26] Any one characteristic can impact a patient’s ability to properly use a specific device and therefore affect compliance with therapy, treatment outcomes, and QOL. The result of a patient’s inability to use a particular device can lead to medication nonadherence and worsening of symptoms leading to an increased frequency of exacerbations. It is important for a clinician to choose an inhaled therapy that is concordant with a patient’s medical needs, preferences, and lifestyle. Nebulized solutions of LABAs should be considered as readily as DPIs and MDIs, particularly for patients with COPD who are unable to use hand-held devices easily, or correctly. The number of steps required to administer treatment by nebulization are far fewer than either an MDI or DPI and, importantly, do not require the patient to synchronize an actuation, only that the patient breath normally (ie, tidal breathing). Studies have shown that both patients and their caregivers are highly satisfied with the nebulized therapy to treat their COPD.[27]

Summary

Improvement in the recognition, diagnosis, and management of COPD remains a major focus in healthcare today. The goals of COPD management can be summarized as the need to reduce symptoms, improve QOL, increase exercise tolerance, decrease exacerbations, prevent disease progression, and decrease mortality. A comprehensive management plan that incorporates strategies to address these facets of care may have a positive impact on patient outcomes. Continued efforts are necessary to keep up with the increasing prevalence of patients with COPD and provide treatment that is consistent with available clinical guidelines and individual patient needs.

Sean M. Gregory, PhD
Published on June 28, 2011

 

References

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