Focus on COPD (Issue 3)
Funding for this newsletter series was provided by
Pulmonary Practice Pearls for Primary Care Physicians
9-part eNewsletter series
Vol 1, Issue 3
Primary care physicians routinely see patients with chronic respiratory diseases, such as asthma and chronic obstructive pulmonary disease (COPD). Although treatment guidelines are available, we still need practical information that translates guidelines and other evidence into diagnosing and managing these diseases. Each issue in the Pulmonary Practice Pearls for Primary Care Physicians eNewsletter series will focus on a key topic in the management of COPD or asthma within the context of current national guidelines and clinical practice. Topics will be brought to life through the presentation of hypothetical clinical cases, and an emphasis will be placed on applying key learnings to clinical practice. Practice tools and links to additional information will be featured in each issue.
Series author
Barbara P. Yawn, MD, MSc, FAAFP
Director of Research
Olmsted Medical Center
Rochester, Minnesota

Dr. Yawn disclosed that she serves on advisory boards for Boehringer Ingelheim and Novartis and has received grant support from Novartis, Boehringer Ingelheim, and Merck.

Kristen Quinn, PhD, and Marissa Buttaro, MPH, of Scientific Connexions in Newtown, Pennsylvania, provided medical writing support for this article through funding from AstraZeneca LP.




Diagnosis of Chronic Obstructive Pulmonary Disease: Focus on Spirometry and Clinical History

Approximately 12.1 million adults in the United States have been diagnosed with chronic obstructive pulmonary disease (COPD),1 which is the third leading cause of death in the United States.2 COPD is characterized by progressive airflow limitation that is not fully reversible, with narrowing of the small airways and destruction of the lung parenchyma, caused by an abnormal inflammatory response to tobacco smoke or other noxious particles.3

Significant extrapulmonary effects may contribute to disease severity in some patients.3 Extrapulmonary effects and morbidities associated with COPD are described in detail in the first newsletter in this series. Pharmacologic treatments and pulmonary rehabilitation can improve functional capacity and quality of life of patients with diagnosed COPD3; however, without a diagnosis, these therapies and the opportunity for improvements do not exist.

In Whom Should a Diagnosis of COPD Be Considered?

Patients aged ≥40 years with respiratory symptoms and a history of exposure to risk factors (eg, tobacco smoke) may have COPD.3 Although not diagnostic themselves, the presence of multiple key indicators of COPD may be used to gauge the likelihood of a COPD diagnosis. The United States Preventive Services Task Force and the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines note that spirometry is indicated as a diagnostic test for COPD and other pulmonary diseases for patients with symptoms suggestive of COPD, including chronic cough, increased sputum production, wheezing, and dyspnea.3,4 Information on key indicators identified by other groups is available in the first newsletter in this series. Additional information on screening tools, including questionnaires and pocket spirometers, is available in the second newsletter in this series.

Cases

It’s just one of those days in your office—a busy preholiday morning during the cold and flu season rush. You have 2 patients complaining of shortness of breath scheduled for morning appointments.

Mary is a 60 year old who retired from a bakery 2 months ago because her legs “gave out.” She noted shortness of breath 3 months ago when her son came to visit. He remarked on her inability to walk up to the second floor of her house without stopping to rest. Mary believes her breathlessness may have become worse in the past 2 weeks. She has trouble sleeping at night and says her ankles are still swollen from years of standing on hard floors in the bakery. She has gained 8 pounds since she stopped working; she says she may be eating more, and she does not exercise regularly. She does not have chest pain or leg pain with walking, but her joints have been aching in the morning and at night for several years. Her hypertension remains under acceptable control with dual therapy.

Charles is a 67 year old with a long history of heart disease, with a previous myocardial infarction (MI) 4 years ago and a 40–pack-year smoking history. Charles quit smoking cigarettes after his MI and now smokes a cigar each evening. Today he complains of shortness of breath and some wheezing at night. He can’t walk up his 4 front steps without stopping to catch his breath. He has no cough, fever, or leg pain. He has been taking a beta-blocker since his MI, but he says shortness of breath has not been a real problem until the last month or two. He has done less since his MI, because his wife worries if he does too much. He did not have cardiac rehabilitation after his MI.

Both of these patients have shortness of breath and risk factors for COPD and cardiovascular disease (CVD)—for Mary, long-term exposure to inhalation of flour in the bakery (COPD) and hypertension (CVD), and for Charles, a 40–pack-year smoking history (COPD and CVD). The differential diagnoses should include COPD as well as CVD. Both patients should have diagnostic spirometry as well as evaluation for CVD.

Note: These are hypothetical case descriptions for teaching purposes.


How Is a Diagnosis Made?
To establish a diagnosis of COPD, clinical history should be used in conjunction with spirometry.3 Physicians should obtain a detailed clinical history that assesses patterns of symptom development, exacerbations, and multiple morbidities.3 In addition, family history of nonasthma airflow obstruction may be predictive of COPD.5 See TABLE 1 for a sample checklist for evaluating a patient’s medical history and the FIGURE for an algorithm for diagnosis of chronic respiratory diseases in primary care.6

A diagnosis of COPD should be confirmed using spirometry.3 In 1 study of 382 patients in 12 US family medicine practices, a clinical diagnosis of COPD or asthma made without spirometry was incorrect in up to 30% of cases.7 In a study of patients diagnosed with COPD in primary care in Australia, misdiagnosis of COPD was more likely in patients who were overweight/obese and with self-reported allergic rhinitis/hay fever.8 Airflow limitation that is not fully reversible, defined as a postbronchodilator ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC) 0.70, indicates COPD (BOX).3,9 A ratio of 0.70 may result in underdiagnosis of COPD in patients 45 years old and overdiagnosis in the elderly. Using the lower limit of normal values for FEV1/FVC, which classifies the bottom 5% of the healthy population as having abnormal airflow based on normal distribution, may help minimize potential misclassifications in the younger and oldest populations.3 The severity of COPD is reflected by the degree of airflow abnormality and is based on the postbronchodilator FEV1 percent of predicted value3 (see FIGURE 1 in the first newsletter in this series).

Chest radiograph, computed tomography (CT), and physical examination may help to exclude other diagnoses (TABLE 2), but should not be the primary tests used to confirm a COPD diagnosis.3 In particular, a chest radiograph is valuable in excluding the presence of cardiac failure and lung masses,3 particularly in patients with significant smoking histories. Comorbid conditions and other complications of COPD may be identified during physical examination.10 Current guidelines do not recommend routine CT of the chest, although this technique may help identify the extent and distribution of emphysema.3 High-resolution CT continues to be studied as a diagnostic tool to identify subtypes of COPD, especially emphysema,11,12 but these tests are expensive and warrant further evaluation of their cost-benefit ratio. The GOLD guidelines recommend that white patients who develop COPD at <45 years of age should be screened for alpha-1 antitrypsin deficiency with serologic testing3; however, screening should be considered for all patients diagnosed with COPD. Alpha-1 antitrypsin deficiency test kits may be obtained at no cost through the Alpha-1 Foundation, the Alpha One International Registry, and other organizations.

Cases: Diagnoses

Mary: On physical examination, you find that she has blood pressure of 140/88 mm Hg, a pulse of 84 beats per minute, and 24 respirations per minute after sitting for 5 minutes. She has no signs of an upper respiratory infection or jugular-venous distention. Her chest sounds are quiet with no wheezing, but she breathes through pursed lips after climbing up onto the examination table. There are no masses in her abdomen, and the liver edge is not palpable. Mary does have large varicose veins on her legs and 2+ edema. A chest radiograph shows a cardiac outline within normal limits and no infiltrates, masses, or enlarged nodes. You do find a large translucent area in the right upper lobe of Mary’s lung. Electrocardiogram findings are within normal limits, except for those consistent with right heart strain. You proceed to spirometry: Mary has a postbronchodilator FEV1 of 2.0 L (54% of predicted), an FVC of 2.0 L (76% of predicted), and an FEV1/FVC of 0.67.

You diagnose Mary with moderate COPD (GOLD stage II). Mary’s long work history at a bakery, with chronic exposure to flour, is the likely etiology of her COPD because she has no history of primary or secondhand exposure to tobacco or other smoke.

Charles: Besides evidence of the previous anterior MI, Charles’ electrocardiogram shows no changes from the last one he had 1 year ago. A chest radiograph does not show cardiac enlargement, a flattened diaphragm, or infiltrates; as always, the radiologist comments that “clinical correlation is advised.” You proceed to spirometry and find that Charles has an FEV1 of 1.6 L (45% of predicted), an FVC of 2.5 L (60% of predicted), and an FEV1/FVC of 0.64. His postbronchodilator FEV1/FVC of 0.65 is basically unchanged. Based on his history (which includes 40 pack-years of smoking), physical examination, and spirometry and electrocardiogram findings, you make a diagnosis of severe COPD (GOLD stage III). It is likely that a spirometry assessment done at the time of follow-up from his MI would have diagnosed the coexistence of CVD and COPD several years earlier, allowing for better planning of his therapy.

Note: These are hypothetical case descriptions for teaching purposes.


Caveats in Making a Diagnosis

The differential diagnosis for COPD includes asthma and other respiratory as well as cardiovascular diseases (TABLE 3).3 Congestive heart failure may be distinguished from COPD with physical examination,3 chest radiograph,3 pulmonary function tests,3 and laboratory tests13; however, the diseases may coexist in 10% to 46% of elderly patients with confirmed or suspected COPD.14 COPD shares common symptoms with many airway diseases (eg, dyspnea, cough, limitation of normal activities).6 When considering a diagnosis of COPD, a smoking history of ≥20 pack-years has been shown to be a strong predictor of airway obstruction.15 Smoking also is a significant risk factor for congestive heart failure16 and CVD.17

In particular, differentiating COPD from asthma can be challenging because these diseases have many overlapping features.18 Differentiation may be particularly difficult in the elderly,18 smokers,10 and patients with a long history of asthma.3 Patients with severe treatment-resistant (formerly called “refractory”) asthma can have persistent patterns of airway obstruction (also called “fixed-airway disease”).19,20 These patients usually require the highest step of asthma treatment (eg, step 6 from current US asthma guidelines21). Their treatment may include high-dose inhaled or oral corticosteroids, and they may have an incomplete response to such therapy.20 Their postbronchodilator spirometry may show incomplete reversibility, looking more like COPD obstruction.22 Asthma and COPD coexist in approximately 3 million individuals in the United States according to data from the National Health and Nutrition Examination Survey III,23 and may be particularly prevalent in individuals with asthma who are exposed to cigarette smoke or other noxious agents.3

Although COPD is defined as airflow limitation that is not fully reversible, evidence from clinical studies suggests that patients with COPD can have a significant bronchodilator response.24-27 Bronchodilator reversibility, or responsiveness, (eg, change in FEV1 or FVC ≥12% and ≥200 mL28) is different from reversibility of airway obstruction (ie, change in FEV1/FVC ratio from <0.70 to ≥0.70).29 Bronchodilator reversibility has been shown to vary with time,30 the bronchodilator used for testing,31 and the criteria used to assess reversibility.27 For this reason, bronchodilator reversibility is not recommended as a diagnostic criterion of COPD or for distinguishing asthma from COPD.3

Other Considerations for Use of Spirometry to Diagnose COPD

Quality spirometric measurements are important for objective and reproducible assessment of airflow limitation.3 To that end, information on equipment and patient preparation and spirogram recording, evaluation, and standardization is available through GOLD and the American Thoracic Society (ATS)/European Respiratory Society Task Force.32-34 In addition, the ATS has initiated a free educational program called Pulmonary Function Testing: Collaborating for Accelerated Change, to support spirometry use and quality spirometry measurement in primary care.35,36 Through collaboration of a pulmonologist and a family physician, the program is designed to provide individual mentorship regarding interpretation and inclusion of spirometry results in the care of patients with asthma and COPD. The program is accredited by the American Academy of Family Physicians (AAFP) for 20 hours and has been added to the resources of the AAFP Measuring, Evaluating, and Translating Research into Care (METRIC) program for recertification by the American Board of Family Medicine (see https://www.aafp.org/online/en/home/cme/selfstudy/metric.html for more information).

Issues regarding use of spirometry in a primary care practice include cost and reimbursement. Spirometers now cost only $1000 to $2000, depending on the type purchased.37 Pocket spirometers,38 which are less expensive than standard diagnostic spirometers—many are $100 or less—can provide comparable FEV1 measurements.39 Pocket spirometers, which were reviewed in the second newsletter in this series, should be used for screening only40; diagnosis of COPD should be confirmed with pre- and postbronchodilator spirometry3 conducted according to established guidelines.41 Physicians may expect Medicare reimbursement of approximately $35 for simple spirometry and $61 for pre- and postbronchodilator spirometry, based on 2011 current procedural terminology (CPT) codes and nationwide Medicare payment information42; private insurance companies may reimburse at varying rates,42 usually higher than Medicare rates. Therefore, the cost of the spirometer is recovered quickly. Appropriate reimbursement depends on use of proper current CPT codes (TABLE 4),42 including evaluation and management (E/M) codes43 as well as ICD-9-CM codes that accurately reflect COPD symptoms and support use of spirometry (TABLE 5).44 E/M codes can be submitted using the modifier -25 code when applicable (see https://www.aafp.org/fpm/2004/1000/p21.html for additional information).

Conclusion

When considering a diagnosis of COPD, review of a detailed medical history can provide important information regarding symptoms, exacerbations, and multiple morbidities. Achieving confidence in a diagnosis of COPD versus CVD or asthma may be particularly difficult in primary care because of overlapping symptoms and disease characteristics. Spirometry assessment performed according to established guidelines3 is required to evaluate patients appropriately, identify additional morbidities, and exclude differential diagnoses.

Cases: Wrap-up

Both patients have COPD. Without spirometry, however, each could have been diagnosed inaccurately—Charles with congestive heart failure and Mary with depression or respiratory infection. Therefore, it is important to use spirometry to make a definitive diagnosis of COPD.

Note: These are hypothetical case descriptions for teaching purposes.

References

  1. American Lung Association. Trends in COPD (chronic bronchitis and emphysema): morbidity and mortality. https://www.lungusa.org/finding-cures/our-research/trend-reports/copd-trend-report.pdf. Published February 2010. Accessed March 13, 2011.
  2. Miniño AM, Xu JQ, Kochanek KD; Division of Vital Statistics. Deaths: preliminary data for 2008. Nat Vital Stat Rep. 2010;59(2):1-52.
  3. Global Initiative for Chronic Obstructive Lung Disease. Global Strategy for the Diagnosis, Management, and Prevention of COPD. https://www.goldcopd.org/uploads/users/files/GOLDReport_April112011.pdf. Updated 2010. Accessed May 10, 2011.
  4. US Preventive Services Task Force. Screening for chronic obstructive pulmonary disease using spirometry: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med. 2008;148:529-534.
  5. Silverman EK. Progress in chronic obstructive pulmonary disease genetics. Proc Am Thorac Soc. 2006;3:405-408.
  6. Levy ML, Fletcher M, Price DP, et al. International Primary Care Respiratory Group (IPCRG) guidelines: diagnosis of respiratory diseases in primary care. Prim Care Respir J. 2006;15:20-34.
  7. Yawn BP, Enright PL, Lemanske RF, et al. Spirometry can be done in family physicians’ offices and alters clinical decisions in management of asthma and COPD. Chest. 2007;132:1162-1168.
  8. Walters JA, Walters EH, Nelson M, et al. Factors associated with misdiagnosis of COPD in primary care [published online ahead of print 2011]. Prim Care Respir J.doi:10.4104/pcrj.2011.00039.
  9. West JB. Tests of pulmonary function; how respiratory physiology is applied to measure lung function. In: Respiratory Physiology: The Essentials. 6th ed. Baltimore, MD: Lippincott Williams & Wilkins; 2000: 132.
  10. Price DB, Yawn BP, Jones RCM. Improving the differential diagnosis of chronic obstructive pulmonary disease in primary care. Mayo Clin Proc. 2010;85:1122-1129.
  11. Kurashima K, Takayanagi N, Satao N, et al. High resolution CT and bronchial reversibility test for diagnosing COPD. Respirology. 2005;10:316-322.
  12. Khan AN, Al Ghanem S, Irion KL, et al. Emphysema imaging. Medscape Reference. https://emedicine.medscape.com/article/355688-overview - showall. Updated February 17, 2009. Accessed June 2, 2011.
  13. Barnes PJ. Chronic obstructive pulmonary disease: effects beyond the lungs. PLoS Med. 2010;7:e1000220.
  14. Rutten FH, Cramer M-JM, Lammers J-WJ, et al. Heart failure and chronic obstructive pulmonary disease: an ignored combination? Eur J Heart Fail. 2006;8:706-711.
  15. Ohar JA, Sadeghnejad A, Meyers DA, et al. Do symptoms predict COPD in smokers? Chest. 2010;137:1345-1353.
  16. He J, Ogden LG, Bazzano LA, et al. Risk factors for congestive heart failure in US men and women. Arch Intern Med. 2001;161:996-1002.
  17. Wolf PA, D’Agostino RB, Kannel WB, et al. Cigarette smoking as a risk factor for stroke: the Framingham Study. JAMA. 1988;259:1025-1029.
  18. Diaz-Guzman E, Mannino DM. Airway obstructive diseases in older adults: from detection to treatment. J Allergy Clin Immunol. 2010;126:702-709.
  19. American Thoracic Society. Proceedings of the ATS workshop on refractory asthma: current understanding, recommendations, and unanswered questions. Am J Respir Crit Care Med. 2000;162:2341-2351.
  20. Bousquet J, Mantzouranie E, Cruz AA, et al. Uniform definition of asthma severity, control, and exacerbations: document presented for the World Health Organization Consultation on Severe Asthma.  J Allergy Clin Immunol. 2010;126:926-938.
  21. National Asthma Education and Prevention Program. Expert Panel Report 3: Guidelines for the Diagnosis and Management of Asthma. Rockville, MD. National Heart, Lung, and Blood Institute, US Department of Human Services; 2007. NIH publication 08-4051.
  22. American Thoracic Society. Proceedings of the ATS workshop on refractory asthma. Am J Respir Crit Care Med. 2000;162:2341-2351.
  23. Soriano JB, Davis KJ, Coleman B, et al. The proportional Venn diagram of obstructive lung disease: two approximations from the United States and the United Kingdom. Chest. 2003;124:474-481.
  24. Bleecker ER, Emmett A, Crater G, et al Lung function and symptom improvement with fluticasone propionate/salmeterol and ipratropium bromide/albuterol in COPD: response by beta-agonist reversibility. Pulm Pharmacol Ther. 2008;21:682-688.
  25. Mahler DA, Donohue JF, Barbee RA, et al. Efficacy of salmeterol xinafoate in the treatment of COPD. Chest. 1999;115:957-965.
  26. Tashkin EP, Celli B, Decramer M, et al. Bronchodilator responsiveness in patients with COPD. Eur Respir J. 2008;31:742-750.
  27. Celli BR, Tashkin DP, Rennard SI, et al. Bronchodilator responsiveness and onset of effect with budesonide/formoterol pMDI in COPD. Respir Med.  2011;105:1176-1188.
  28. American Thoracic Society. Lung function testing: selection of reference values and interpretive strategies. Am Rev Respir Dis. 1991;144:1202-1218.
  29. Prentice HA, Mannino DM, Caldwell GG, Bush HM. Significant bronchodilator responsiveness and “reversibility” in a population sample. COPD. 2010;7:323-330.
  30. Anthonisen NR, Wright EC. Bronchodilator response in chronic obstructive pulmonary disease. Am Rev Respir Dis. 1986;133:814-819.
  31. Donohue JF. Therapeutic responses in asthma and COPD: bronchodilators. Chest. 2004;126(suppl):125S-137S.
  32. Global Initiative for Chronic Obstructive Lung Disease. Pocket Guide to COPD Diagnosis, Management, and Prevention: A Guide for Health Care Professionals. https://www.goldcopd.org/uploads/users/files/GOLD_Pocket_2010Mar31.pdf. Updated 2010. Accessed August 3, 2011.
  33. Miller MR, Crapo R, Hankinson J, et al. General considerations for lung function testing. Eur Respir J. 2005;26:153-161.
  34. Miller MR, Hankinson J, Brusasco V, et al. Standardisation of spirometry. Eur Respir J. 2005;26:319-338.
  35. Yawn BP, Enright P, Scanlon P, et al. Support for spirometry use in primary care: an ATS educational program [abstract]. Am J Respir Crit Care Med. 2011;183:A2945.
  36. American Thoracic Society. Pulmonary function testing. https://www.thoracic.org/education/pulmonary-function-testing/index.php. Accessed July 29, 2011.
  37. Stoloff SW. Diagnosis and treatment of patients with chronic obstructive pulmonary disease in the primary care setting: focus on the role of spirometry and bronchodilator reversibility. J Fam Pract. 2011;60(4 suppl):S9-S16.
  38. Yawn B. Screening for chronic obstructive pulmonary disease (COPD) in primary care. In: Pulmonary Practice Pearls for Primary Care Physicians. J Fam Pract. 2011. https://newsletter.qhc.com/JFP/JFP_COPDissue2.htm.
  39. Liistro G, Vanwelde C, Vincken W, et al; for the COPD Advisory Board. Technical and functional assessment of 10 office spirometers: a multicenter comparative study. Chest. 2006;130:657-665.
  40. Rytila P, Helin T, Kinnula V. The use of microspirometry in detecting lowered FEV1 value in current or former cigarette smokers. Prim Care Respir J. 2008;17:232-237.
  41. American Thoracic Society. Standardization of spirometry, 1994 update. Am J Respir Crit Care Med. 1995;152:1107-1136.
  42. American Medical Association. Current Procedural Terminology. 4th ed. https://catalog.ama-assn.org/Catalog/cpt/cpt_search.jsp. Accessed June 21, 2011.
  43. Felger TA, Felger M. Getting paid: understanding when to use modifier -25. Fam Pract Manag. 2004;11:21-22. https://www.aafp.org/fpm/2004/1000/p21.html. Accessed June 16, 2011.
  44. Centers for Disease Control and Prevention. International Classification of Diseases, 9th revision, clinical modification (ICD-9-CM). https://www.cdc.gov/nchs/icd/icd9cm.htm. Accessed June 21, 2011.

Table 1. Sample Checklist for Evaluating Medical History During Potential Diagnosis of COPD3
Topic

Details for Discussion With Patient

Exposure to risk factors

Smoking
Occupational or environmental exposures

Past medical history

Asthma
Allergy
Sinusitis
Nasal polyps
Respiratory infections in childhood
Other respiratory diseases

Family history

COPD
Other chronic respiratory diseases
Pattern of symptom development

Age at onset
Initial symptoms of COPD may include increased breathlessness, more frequent “winter colds,” social restriction
History of exacerbations or previous hospitalizations for respiratory disorder

Periodic worsening of symptoms may not have been defined as an exacerbation of COPD
Presence of multiple morbidities

Heart disease
Malignancies
Osteoporosis
Musculoskeletal disorders (may contribute to restriction of activity)
Impact of disease on a patient’s life

Limitation of activity
Missed work and economic impact
Effect on family routines
Feelings of depression or anxiety
Additional factors

Reducing risk factors (eg, smoking cessation)
Social and family support available to the patient

COPD, chronic obstructive pulmonary disease.

Figure. Algorithm for Diagnosis of Chronic Respiratory Diseases in Primary Care6

COPD, chronic obstructive pulmonary disease.

Table 2. Additional Tests to Consider When Establishing a Diagnosis of Moderate to Very Severe COPD3
Item

Value in Establishing Diagnosis or Monitoring Disease Progression
Lung function and imaging

Bronchodilator reversibility testing

Excludes other diagnoses (eg, asthma)

Cannot predict disease progression

Chest radiograph

Excludes alternative diagnoses (eg, cardiac failure)

Establishes presence of significant multiple morbidities

CT or high-resolution CT

Aids in differential diagnoses
Laboratory tests

Arterial blood gas measurement

Assesses development of respiratory failure in patients with oxygen saturation <92% based on pulse oximetry*

Hematocrit

Assesses anemia and polycythemia (hematocrit >55%), which may develop in the presence of arterial hypoxemia, especially in continuing smokers

Low hematocrit in patients on long-term oxygen treatment indicates poor prognosis

Function and activities
Respiratory muscle function Assesses dyspnea or hypercapnia not explained by lung function testing or when peripheral muscle weakness is suspected
Sleep studies May be indicated when hypoxemia or right heart failure develops in the presence of relatively mild airflow limitation or when symptoms suggest sleep apnea
Exercise testing Measures exercise capacity, primarily in conjunction with pulmonary rehabilitation programs
Genetic factors
Alpha-1 trypsin deficiency screening† Indicates need for family screening or appropriate counseling

COPD, chronic obstructive pulmonary disease; CT, computed tomography; PaCO2, partial pressure of carbon dioxide; PaO2, partial pressure of oxygen.

*Defined as PaO2 <8.0 kPa (60 mm Hg) with or without PaCO2 >6.7 kPa (50 mm Hg) at sea level.
†Valuable for white patients who develop COPD at an early age (<45 years) or who have a strong family history of the disease.

Table 3. Differential Diagnosis of COPD3
Diagnosis

Suggestive Features

COPD

Onset in mid-life
Symptoms slowly progressive
Long history of tobacco smoking
Dyspnea during exercise
Largely irreversible airflow limitation

Asthma

Onset early in life (often childhood)
Symptoms vary from day to day
Symptoms at night/early morning
Allergy, rhinitis, and/or eczema also present
Family history of asthma
Largely reversible airflow limitation

Congestive heart failure

Fine basilar crackles on auscultation
Chest radiograph shows dilated heart, pulmonary edema
Pulmonary function tests indicate volume restriction, not airflow limitation

Bronchiectasis

Large volumes of purulent sputum
Commonly associated with bacterial infection
Coarse crackles/clubbing on auscultation
Chest radiograph/CT scan shows bronchial dilation, bronchial wall thickening

Tuberculosis

Onset—all ages
Chest radiograph shows lung infiltrate
Microbiological confirmation
High local prevalence of tuberculosis

Obliterative bronchiolitis

Onset in younger age, nonsmokers
May have history of rheumatoid arthritis or fume exposure
CT scan on expiration shows hypodense areas

Diffuse panbronchiolitis

Most patients are male and nonsmokers
Almost all have chronic sinusitis
Chest radiograph and HRCT scans show diffuse small centrilobular nodular opacities and hyperinflation

These features tend to be characteristic of the respective diseases but do not occur in every case. For example, a person who has never smoked may develop COPD (especially in the developing world where other risk factors may be more important than cigarette smoking); asthma may develop in adult and even elderly patients.

COPD, chronic obstructive pulmonary disease; CT, computed tomography; HRCT, high-resolution computed tomography.

From the Global Strategy for Diagnosis, Management, and Prevention of COPD, used with permission from the Global Initiative for Chronic Obstructive Lung Disease (GOLD), www.goldcopd.org.


Table 4. Sample CPT Codes for Spirometry Related to Diagnosis of COPD42
Code*

Description

94010

Spirometry, including graphic record, total and timed vital capacity, expiratory flow rate measurement(s), with or without maximal voluntary ventilation

94060

Bronchodilation responsiveness, spirometry as in 94010, pre- and postbronchodilator administration

94375

Respiratory flow volume loop

94620

Pulmonary stress testing; simple (eg, 6-minute walk test, prolonged exercise test for bronchospasm with pre- and postspirometry and oximetry)

94664

Demonstration and/or evaluation of patient utilization of an aerosol generator, nebulizer, metered-dose inhaler, or IPPB device
99211

Office or other outpatient visit for the evaluation and management of an established patient that may not require the presence of a physician. Usually, the presenting problem(s) are minimal. Typically, 5 minutes are spent performing or supervising these services.

COPD, chronic obstructive pulmonary disease; CPT, current procedural terminology; IPPB, intermittent positive-pressure breathing.

*Sample spirometry-related codes; comprehensive CPT code lists42 should be consulted in clinical practice.



Table 5. Sample ICD-9-CM Codes Relevant to COPD44
Code*

Description

305.1

Tobacco use disorder

490

Bronchitis

491

Chronic bronchitis

491.21

COPD with acute exacerbation

492

Emphysema
496

Chronic airway obstruction not elsewhere classified
786.0 Dyspnea
786.05 Shortness of breath
786.07 Wheezing
786.2 Cough

COPD, chronic obstructive pulmonary disease; ICD-9-CM, International Classification of Diseases, ninth revision, Clinical Modification.

*Sample ICD-9-CM codes related to COPD; comprehensive ICD-9-CM code lists44 should be consulted in clinical practice.