High Prevalence of Chronic Obstructive Pulmonary Disease Among Veterans in the Urban Midwest

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1 MILITARY MEDICINE, 176, 5:552, 2011 High Prevalence of Chronic Obstructive Pulmonary Disease Among Veterans in the Urban Midwest Daniel E. Murphy, MD * ; Zeshan Chaudhry * ; Khalid F. Almoosa, MD, MS ; Ralph J. Panos, MD * ABSTRACT Although chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality within the Veterans Health care Administration, its prevalence and recognition are not known. We measured airflow limitation and diagnosed COPD at the Cincinnati Veteran s Administration Medical Center. Participants were 326 outpatients who performed spirometry and completed questionnaires. Health care-provider-diagnosis and self-diagnosis of COPD were compared with COPD defined by forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) < 0.7 (fixed ratio) and (FEV1/FVC)/lower limit of normal (LLN) < 1.0. COPD prevalence was 43% (95% confidence interval: 36.9, 48.1) by fixed ratio and 33% (95% confidence interval: 27.2, 36.8) by LLN. Eighteen percent of the patients had health care-provider-recorded and 23% had self-reported diagnoses of COPD. Positive predictive values for the diagnosis of COPD were 79% and 64% for healthcare providers versus 68% and 62% for patients; negative predictive values were 64% and 74% for healthcare providers versus 64% and 76% for patients (fixed ratio and LLN, respectively). COPD prevalence is higher among Cincinnati veterans than among general U.S. population. COPD is under-recognized by both health care providers and veterans. INTRODUCTION Chronic obstructive pulmonary disease (COPD) was the fourth leading cause of mortality in the United States in It is predicted to become the second leading cause of death in the United States by and the fourth leading cause of death worldwide by COPD is common in the general U.S. population and among veterans cared for by the Veterans Health care Administration (VHA). The Third National Health and Nutrition Examination Survey (NHANES III) estimated that the prevalence of COPD was 6.8 to 8.5% within the general U.S. population. 3 COPD prevalence was estimated to be greater in current (12.5%) and former (9.4%) smokers than in never smokers (5.8%). 3 Among veterans hospitalized in the VHA in 2005, COPD was the fourth most common discharge diagnosis; approximately one-third of medical admissions and one-sixth of all inpatients had a diagnosis of COPD. 7 In a utilization review study from October 1996 to March 2001, 19% of men and 17% of women in the VHA were diagnosed with COPD. 7 The presence of COPD is often underestimated by health care providers because patients with few or no respiratory symptoms are frequently not assessed by pulmonary function testing Damarla and colleagues demonstrated that patients admitted to hospital for COPD are much less likely to get confirmatory spirometry (35%) than an echocardiogram (78%) to diagnose congestive heart failure. 11 Multiple international and domestic epidemiologic studies demonstrate underdiagnosis of COPD in 52 to 91% of individuals with airflow limitation. 3,12 14 Although smoking is the major cause of COPD, other factors including age, gender, and occupational exposures contribute to its development. 1 In 2002, Hnizdo et al 15 showed that, among various occupations, the prevalence of COPD was highest (13.4%) in armed forces personnel. The prevalence of smoking is approximately 5% higher in military personnel than in civilians, 16,17 and veterans are more likely to have ever smoked (74%) than non-veterans (48%). 18 The prevalence of occupational exposures that predispose to the development of COPD and occur after military service is unknown. Although COPD is a very common diagnosis among patients in the VHA and the prevalence of smoking is high among active duty military personnel and veterans, the prevalence of COPD within the U.S. veteran population has not been measured using spirometry. We hypothesized that the prevalence of COPD among veterans served by the Cincinnati Veteran s Administration Medical Center (VAMC) is greater than that in the general U.S. population and that COPD is underrecognized by veterans and their health care providers. * Pulmonary, Critical Care, and Sleep Division, Cincinnati Veterans Affairs Medical Center, 3200 Vine Street, Cincinnati, OH Pulmonary, Critical Care, and Sleep Division, University of Cincinnati School of Medicine, Room 6111 ML 0564, 231 Albert Sabin Way, Cincinnati, OH Division of Pulmonary, Critical Care, and Sleep Medicine, University of Texas Health Science Center, Suite 600, 6410 Fannin Street, Houston, TX This data was presented at the American College of Physicians meeting in Washington, DC, and the American Thoracic Society Meeting in Toronto in May MATERIALS AND METHODS Subjects were recruited from the outpatient waiting area of the Cincinnati VAMC in random, chronologic order and represented a sampling of patients from the primary care, mental health, and medical and surgical specialty clinics ( Fig. 1 ). Patients with acute respiratory complaints were not recruited. Each participant completed a questionnaire about smoking habits, occupational exposures, and respiratory diagnoses and symptoms 19,20 (Appendix A). Any subject who stated 552 MILITARY MEDICINE, Vol. 176, May 2011

2 that they had COPD, emphysema, or chronic bronchitis was termed self-diagnosis. A patient with COPD, emphysema, or chronic bronchitis in their electronic medical record (EMR) problem list was termed health care-provider diagnosis. Spirometry was performed using a Spiroxcard and Office Medic 4.23 software (QRS Diagnostic, Plymouth, MN) with a Compaq laptop computer (Compaq Presario 3000, Hewlett Packard, Plano, Texas) according to the American Thoracic Society guidelines. 21 Spirometry was performed without pretreatment with bronchodilators. Maximal and consistent data were produced using no more than 8 attempts and the best effort was selected for analysis. All spirometry tracings were reviewed and participants with unacceptable or irreproducible efforts were excluded. COPD was defined by 2 thresholds: 1) forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) ratio < 0.7 (fixed ratio), 1 and 2) (FEV1/FVC)/ lower limit of normal (LLN) ratio < 1.0. LLN was calculated based on NHANES III. 3 The estimated prevalence of COPD at the Cincinnati VAMC is 8.7% on the basis of the recorded diagnosis of COPD in the EMR and is similar to the U.S. population prevalence of 6.8 to 8.5%. 3,22 We performed sample size calculations using a COPD prevalence ranging from 8.7 to 15%, confidence levels of 95 and 99% and, assuming a population of 15,000 individuals, determined a sample size of approximately 1, Interim analysis showed that the measured COPD prevalence was significantly greater than that predicted. Based upon our sample size of 347 patients and a measured prevalence of 43.3%, the 95% confidence interval (CI) is Maintaining a measured prevalence of 43%, the 95% CI would be 5.61 for a sample size of 500 and 3.9 for a sample size of 1,000. Based on a minimal reduction in 95% CI and a measured prevalence approximately 5-fold greater than both the NHANES III and our pre-study estimates, the study was stopped after enrolling 347 patients. Data were entered into an Excel spreadsheet (Microsoft, Redmond, WA) and graphs generated using PSI-Plot (Poly Software International Pearl River, NY). Data are presented as mean ± SEM. Statistical analysis was performed using χ 2 tests. 24 Significance was set at p <0.05. The protocol was approved by the Cincinnati VAMC Research and Development Committee and the University of Cincinnati Institutional Review Board. Informed consent and Health Information Portability and Accountability Authorization were obtained from all participants before enrollment. FIGURE 1. participants. Study flow diagram showing inclusion and exclusion of RESULTS Three hundred and forty-seven subjects enrolled in the study ( Fig. 1 ). Clinical characteristics of the study population are presented in Table I. The majority of patients were ever cigarette smokers (83%) who had smoked for 41 ± 2 pack-. Ninety-one patients (30% of the ever smokers) also reported smoking other forms of tobacco either in addition to or instead TABLE I. Clinical Characteristics of the Study Population n (%total) FEV1/FVC < 0.70 FEV1/FVC > 0.70 p Value (FEV1/FVC)/ (LLN) < 1.0 (FEV1/FVC)/ (LLN) > 1.0 p Value n Age () Mean ± SEM (Range) 60 ± 0.8 (27 87) > (51%) 80 (43%) (45%) 104 (47%) 0.66 < (49%) 105 (57%) (55%) 115 (53%) 0.66 Male 312 (96%) 138 (97%) 174 (95%) (76%) 208 (95%) 0.35 Ethnicity Caucasian 250 (77%) 105 (74%) 145 (79%) (69%) 176 (80%) 0.02 African American 72 (22%) 36 (25%) 36 (20%) (31%) 39 (18%) Other 4 (1%) 0 4 (2%) (2%) 0.16 Ever Smoker 270 (83%) 132 (93%) 138 (75%) (94%) 169 (77%) Current Smoker 123 (38%) 60 (42%) 63 (34%) (47%) 73 (33%) 0.02 <50 pk/yrs 183 (56%) 79 (56%) 104 (57%) (55%) 124 (56%) 0.8 >50 pk/yrs 85 (36%) 52 (37%) 33 (18%) (38%) 44 (20%) Never Smoker 56 (17%) 9 (6%) 47 (26%) (6%) 50 (23%) Pk/yrs, pack ; ever smoker participant smoked >100 cigarettes in his or her lifetime. MILITARY MEDICINE, Vol. 176, May

3 of cigarettes. Eighty-six percent of participants reported ever smoking any type of tobacco product. Occupational histories are presented in Table II. Nearly three quarters of the participants had worked in occupations associated with an increased risk of COPD. The most common jobs were in the construction, chemical, and lumber industries. One quarter of the participants had smoked and had 3 or more occupational exposures. Only 5% had neither smoked nor worked in an occupation predisposing them to COPD. The distributions of FEV1, FVC, FEV1/FVC, and (FEV1/ FVC)/LLN are presented in Figure 2. The FEV1 was 2.54 ± L, the FVC was 3.64 ± 0.05 L, and FEV1/FVC was 0.69 ± 0.01 for all participants. The prevalence of COPD was 43.3% (141/326) (95% CI: 36.9, 48.1) using FEV1/FVC < 0.7 (fixed ratio) and 32.8% (107/326) (95% CI: 27.2, 36.8) using (FEV1/FVC)/LLN < 1.0 (LLN) as the threshold for the diagnosis of obstruction. The relationship between COPD defined by fixed ratio and by LLN is presented in Figure 3. Approximately one quarter (24%) of the patients with COPD defined by fixed ratio were excluded by the LLN criteria. No patients with an FEV1/FVC > 0.7 had an (FEV1/FVC)/LLN < 1.0. Of the 325 participants with acceptable spirometry and accessible records, 58 (18%) had a health care-provider diagnosis of COPD and 74 (23%) had a self-diagnosis of COPD (Table III ). Health care-provider diagnosis was sensitive in 46 of the 141 subjects (33%) with COPD based on fixed ratio and in 37 of 106 (35%) using LLN thresholds to define obstruction. The sensitivity of the patients self-diagnoses of COPD was similar to the sensitivity of the health careproviders diagnoses, 35% for fixed ratio and 43% for LLN. Both the health care-provider diagnoses of COPD and the patient self-diagnoses of COPD had relatively low sensitivity and specificity for the presence of COPD defined by either threshold ( Table III ). Of the 322 patients who completed the survey (17%), 55 self-reported a history or current diagnosis of asthma. However, 69% of these subjects also had a self-diagnosis of COPD. In addition, 50 of 55 participants (91%) with a selfdiagnosis of asthma were ever smokers and 46% were older than 40 at the time of asthma diagnosis. Finally, 29 of the 55 subjects (53%) had airflow limitation by fixed ratio and 28 (51%) had airflow limitation by LLN, respectively. Thus, we could not reliably distinguish airflow limitation solely because of asthma from COPD or a mixed process and, therefore, classified all subjects with obstruction as COPD. DISCUSSION Our study demonstrates a higher prevalence of COPD among Veterans at the Cincinnati VAMC than in the general U.S. population.3 The prevalence varied from 33% to 43% depending upon whether the LLN or a fixed FEV1/FVC ratio was used to define airflow limitation. Most participants were male, ever smokers, and had worked in occupations associated with the development of COPD. Despite this elevated prevalence of airflow limitation, COPD was under-recognized by both health care providers and veterans. The prevalence of COPD in these Cincinnati veterans, 33 to 43%, was greater than has been reported in many other populations. 3,25 27 A study of the prevalence of COPD among residents of southeastern Kentucky over the age of 40 using the BOLD (Burden of Obstructive Lung Disease) survey protocol demonstrated that 19.7% had GOLD stage 1 COPD or higher. 27 This study utilized post-bronchodilator spirometry, whereas our study used pre-bronchodilator spirometry that may overestimate GOLD defined COPD The southeastern Kentucky study showed a higher prevalence of COPD in subpopulations that were older and ever smokers. 27 TABLE II. Self-Reported Occupations in the Study Population Occupation n (%) COPD FEV1/ FVC < 0.7 COPD FEV1/ FVC > 0.7 p Value COPD (FEV1/FVC)/ LLN < 1.0 COPD (FEV1/FVC)/ LLN > 1.0 p Value n Agriculture 65 (20%) 22 (16%) 43 (24%) (13%) 51 (24%) 0.03 Forestry/Fishing 22 (6.8%) 12 (9%) 10 (5%) (9%) 12 (6%) 0.19 Mining 14 (4.4%) 6 (4%) 8 (4%) (0%) 14 (6%) Construction 146(45%) 66 (47%) 80 (44%) (47%) 96 (44%) 0.64 Textile 28 (8.7%) 13 (9%) 15 (8%) (8%) 19 (9%) 0.93 Chemical 131(41%) 63 (45%) 68 (37%) (42%) 87 (40%) 0.83 Rubber 62 (19%) 28 (20%) 34 (19%) (20%) 41 (19%) 0.86 Lumber 111 (34%) 53 (38%) 58 (32%) (39%) 70 (32%) 0.27 No Noted Occupation 84 (26%) 33 (24%) 51 (28%) (25%) 57 (26%) Occupations 143 (44%) 64 (46%) 79 (43%) (47%) 93 (43%) 0.49 >2 Occupations 95 (30%) 42 (30%) 53 (29%) (27%) 66 (31%) 0.55 No Occupations + Ever Smoker 69 (21%) 30 (22%) 39 (21%) (24%) 44 (20%) Occupations + Ever Smoker 118 (37%) 60 (43%) 58 (32%) (44%) 71 (33%) >2 Exposures + Ever Smoker 79 (25%) 40 (29%) 39 (21%) (26%) 51 (24%) 0.58 No Occupations + Never Smoker 15 (5%) 3 (2%) 12 (7%) (2%) 13 (6%) Occupations + Never Smoker 25 (8%) 4 (3%) 21 (11%) (3%) 22 (10%) 0.02 >2 Exposures + Never Smoker 16 (5%) 2 (1%) 14 (8%) (0.9%) 15 (7%) MILITARY MEDICINE, Vol. 176, May 2011

4 FIGURE 2. Spirometry results for the 326 participants who performed technically adequate studies. (A) The distribution of FEV1; (B) The distribution of FVC; (C) The distribution of FEV1/FVC. Fixed ratio COPD was defined as FEV1/FVC < 0.7; (D) The distribution of (FEV1/FVC)/LLN. LLN COPD was defined as (FEV1/FVC)/LLN < 1.0. FIGURE 3. Relationship between COPD defined by fixed ratio, FEV1/ FVC < 0.7, and LLN, (FEV1/FVC)/LLN < 1.0. Approximately one quarter (24%) of the patients with COPD defined by fixed ratio were excluded by the LLN threshold. Our study was located in a more urban region with a higher smoking rate (83% compared with 59%) and our population was composed mainly of older men. These factors and the occupational exposures may account for the higher measured prevalence of COPD. Further, the prevalence measured in our study is at least 5-fold higher than that determined in the general American civilian population, 6.8 to 8.5% 3,31 during NHANES III, which also used pre-bronchodilator spirometry. Smoking is the single greatest risk factor for the development of COPD and is estimated to cause up to 80 to 90% of COPD. 1,2 Over 80% of our study participants were ever smokers and 38% were actively smoking at the time of the study. Studies from northern Sweden suggest that up to half of elderly smokers may develop COPD defined by fixed ratio. 32 Other risk factors for the development of COPD include occupational exposures to chemicals, dusts, and fumes. 15 Working in the armed forces is associated with a 2-fold increased risk of COPD, and all participants in this study had served in the U.S. MILITARY MEDICINE, Vol. 176, May

5 TABLE III. Sensitivity and Specificity of Patient Self-diagnosis and Caregiver Diagnosis of COPD Spirometry FEV1/ FVC < 0.7 Patient Self-diagnosis + Patient Self-diagnosis Total Sensitivity Specificity Positive Predictive Value Negative Predictive Value COPD COPD Total Health care-provider Health care-provider Diagnosis Diagnosis + COPD COPD Total Spirometry (FEV1/ Patient Self-diagnosis + Patient Self-diagnosis FVC)/LLN < 1.0 COPD COPD Total Health care-provider Health care-provider diagnosis diagnosis + COPD COPD Total military. 15 In addition, nearly every participant had worked in an industry associated with the development of obstructive lung disease. Nearly all the participants in this study were male; and men, especially those who are older and actively smoking, have a higher prevalence of COPD. 33 A study of 104 general practices in the Netherlands revealed that the prevalence of patient self-reported obstructive lung disease, either asthma or COPD (9.7%), was nearly twice as high as that recorded in health care-providers records (5.2%). 34 Similarly, in our study, the self-reported diagnosis of COPD occurred more frequently than the health care-provider diagnosis documented in the EMR. Methvin et al 27 showed that, although COPD was very common in southeastern Kentucky, it was often under-diagnosed. A unique feature of our study was the ability to correlate measured airflow limitation with patient and health care-provider recognition of COPD ( Table III ). Previous studies have only been able to use selfreported diagnoses to assess earlier diagnosis of COPD. 3,19,25,26 Our study shows that up to one-third of self-diagnosed patients and health care-provider diagnosed patients do not have airway obstruction based on spirometry. Nearly twothirds of patients with airflow obstruction do not have a selfreported diagnosis or health care-provider diagnosis of COPD. Earlier studies based on NHANES III demonstrated similar levels of under-diagnosis (63.3 to 71.1%). 3,31 These results suggest that the level of under-recognized COPD in veterans is similar to that within the general U.S. population despite the higher prevalence within this group. Different definitions of COPD may have profound effects on the prevalence of obstructive lung disease within a population.35,36 Use of (FEV1/FVC)/LLN<1.0 as the threshold for COPD reduced the prevalence of COPD in our cohort by approximately one quarter, from 43 to 33%. Other studies have shown similar results and that this effect is more pronounced in elderly patients The mean age in our study was 60, and Swanney et al 37 showed that the median age at which the LLN decreased below 0.7 was 48 in men. The clinical significance of these differences is unclear, however. Individuals who are diagnosed with COPD by fixed ratio and not by LLN have an increased use of respiratory-related health care resources compared to a normal population Although the GOLD guidelines advocate the use of postbronchodilator spirometry and a fixed ratio, FEV1/FVC<0.7, for the diagnosis of COPD, the most recent American Thoracic Society/European Respiratory Society strategies for the interpretation of pulmonary function studies recommend the use of the LLN, the lower confidence level or fifth percentile, as the threshold for the definition of airflow limitation. 43,44 In this study, we used pre-bronchodilator spirometry and both fixed ratio and LLN thresholds for the diagnosis of COPD. Prebronchodilator spirometry with a fixed ratio may over-diagnose COPD by up to one-third There are, however, few studies utilizing post-bronchodilator FEV1/FVC LLN thresholds for the diagnosis of airflow limitation. In a study to develop reference values for post-bronchodilator lung function, Johannessen et al 43 showed that the post-bronchodilator FEV1/FVC LLN exceeded 0.7 for both genders at all ages. Another study found that the FEV1/FVC is less than the LLN more often when using post-bronchodilator reference values than when prebronchodilator reference values are used. 28 Irrespective of the threshold used to define COPD, the prevalence of COPD measured in this Midwest, urban veteran population appears to be increased and related to the gender, age, smoking history, and occupational exposures of the participants. Our study has several potential limitations. There may have been an enrollment bias as only half of the veterans who were approached in the waiting area agreed to participate. Those who enrolled may have had an increased awareness or 556 MILITARY MEDICINE, Vol. 176, May 2011

6 concern for respiratory symptoms or higher smoking rates. Patients in the waiting area may represent a sicker group than the entire veteran population served by the Cincinnati VAMC. The health care-provider-diagnosis of COPD was based on the patient s problem list and not on progress notes or medications and, therefore, may have underestimated health careproviders rate of recognition if they did not enter COPD into the problem list. Inclusion within the problem list does provide a documented objective diagnosis and, since it is used for coding and billing purposes, was felt to be the most impartial measure for health care-provider recognition of COPD. Also, our survey of occupational exposures was based upon patient self-reporting and did not address specific exposure(s) or duration of those exposures. Thus, we are only able to associate self-reported occupations, but cannot quantify occupational exposures. We attempted to distinguish airflow limitation as a result of COPD from asthma by questionnaire and found considerable overlap in patient and health care-provider diagnoses of asthma and COPD. Further, half the patients reporting a diagnosis of asthma were smokers diagnosed after age 40. It is possible that a small minority of patients may have had airflow limitation solely as a result of asthma, but we were not able to identify these individuals reliably and, therefore, classified all participants with airflow limitation as COPD. Finally, other causes of airflow limitation may have also been included. CONCLUSIONS This study shows that veterans in Cincinnati have increased prevalence and risk factors for the development of COPD. Most of the veterans were male ever smokers and over onethird were currently smoking. They were older and most had worked in occupations that could contribute to the development of airflow obstruction. The prevalence of COPD varied from 33 to 43% depending upon the threshold of airflow limitation used. COPD was under-recognized by both health careproviders and participants. The high prevalence of risk factors for the development of COPD and the high measured prevalence of COPD among Cincinnati veterans suggest that further studies of COPD prevalence in veterans regionally and nationally and its impact on health care in the VHA are warranted. ACKNOWLEDGMENTS The authors thank Dr. Francis McCormack for help with preparation of the manuscript and the staff in the Cincinnati Veterans Emergency Room and Pharmacy for sharing their space to allow the study to be performed. Authors have obtained written permission from all persons named in the acknowledgment. This study was supported in part by an investigator-initiated grant (<$15,000) from Boerhringer-Ingelheim, who did not participate in study development, conduct, data analysis, or manuscript preparation. APPENDIX Prevalence of Chronic Obstructive Lung Disease at the Cincinnati VAMC Thank you for agreeing to participate in this study to measure the prevalence of chronic obstructive lung disease at the Cincinnati VAMC. Please complete this questionnaire and answer every question to the best of your ability. If you have any questions, please ask one of the investigators. Name Date of Birth Age Social Security Number Height Weight Have you smoked at least 100 cigarettes during your entire life? If yes, For how many have you smoked? On average, how many packs of cigarettes have you smoked per day? packs per day Are you currently smoking? Have you ever smoked any other tobacco products? If yes, For cigars, for how many have you smoked cigars? On average, how many cigars have you smoked per day? Cigars per day If you have smoked any other tobacco products, please describe and state the number per day and for how long? Have you ever worked in any of these occupations? Check all that apply. Agriculture production Agricultural services, forestry, and fishing Mining Construction Textile mill products Chemicals, petroleum, and coal products Rubber, plastics, and leather products Lumber and wood products, including furniture Cough Do you usually cough at all on getting up or first thing in the morning? Do you usually cough at all during the rest of the day or night? MILITARY MEDICINE, Vol. 176, May

7 Do you usually have a cough like this on most days for 3 consecutive months or more during the year? For how many have you had this cough? Do you wake with cough during the night? Phlegm Do you usually bring up phlegm from your chest? Do you usually bring up phlegm like this as much as twice a day for 4 or more days out of the week? Do you usually bring up phlegm at all on getting up, or first thing in the morning? Do you usually bring up phlegm at all during the rest of the day or night? Do you bring up phlegm like this on at least half of the days for 3 consecutive months or more during the year? For how many have you been troubled with phlegm? Does your chest ever sound wheezy or whistling: When you have a cold? Occasionally apart from colds? Most days or nights? For how many has this been present? Have you ever had an attack of wheezing that made you feel short of breath? How old were you when you had your first such attack? Have you had 2 or more attacks of wheezing? Have you ever required medicine or treatment for such attacks? Breathlessness If disabled from walking by any condition other than heart disease (such as arthritis or stroke), please describe: Are you troubled by shortness of breath when hurrying on the level or walking up a slight hill? Do you have to walk slower than people of your own age on the level because of breathlessness? Do you every have to stop for breath when walking at your own pace on the level? Do you every have to stop for breath after walking about 100 yards on the level? Do you every have to stop for breath after walking after a few minutes on the level? Are you breathless on bathing or dressing or undressing? Are you too breathless to leave the house? Is your breathing worse in the morning than it is in the evening? Do you wake with shortness of breath during the night? Have you ever had hay fever? Do you have hay fever now? Have you ever had eczema? Do you have eczema now? Do you have an allergy to anything besides medications? 558 MILITARY MEDICINE, Vol. 176, May 2011

8 Has a doctor ever told you that you had chronic bronchitis? Do you still have it? At what age did it start? Has a doctor ever told you that you had emphysema? Do you still have it? At what age was emphysema diagnosed? old Has a doctor ever told you that you had chronic obstructive pulmonary disease COPD? Do you still have chronic obstructive pulmonary disease COPD? At what age was chronic obstructive pulmonary disease COPD diagnosed? old Has a doctor ever told you that you had asthma? Do you still have asthma? At what age was asthma diagnosed? old If you no longer have asthma, at what age did it stop? old REFERENCES A1. Murtagh E, Heaney L, Gingles J, et al : The prevalence of obstructive lung disease in a general population sample: the NICECOPD Study. Eur J Epidem 2005 ; 20: A2. Third National Health and Nutrition Examination Survey. nchs/nhanes/nhanes_questionnaires.htm. REFERENCES 1. 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