Background: The six minutes walk test has been increasingly utilized to assess the effectiveness of different clinical and surgical treatment options in pulmonary diseases. However lack of standardization for their performance may influence measurements and jeopardize assessment of the functional capacity of patients with cardiopulmonary disease. Objective: To determine the possible effects of learning on the distance covered during the six minute walk test for bearers of chronic obstructive pulmonary disease. Method: A retrospective analysis of 35 medical records of COPD patients referred to the Pulmonary Rehabilitation Program of the University Hospital of Brasília was carried out. On alternate days these patients had performed two six minutes walk tests, spirometry and arterial blood gas analysis. Clinical and functional diagnosis was based upon the history of exposure to risk factors, mucus production, dyspnea and spirometric dysfunction after use of bronchodilators. The Student test was used for the comparison of results that were different. Results: The distances covered in the second six-minute walk test (515 ± 82 meters) were greater than those covered in the first six-minute walk test (480 ± 85 metros), with statistically significant differences (p<0.05). However measurements of the muscular effort and perception of dyspnea (Borg scale), peripheral blood oxygen saturation (SpO2), respiratory and heart rates did not disclose any statistically significant differences between the two tests (p<0.05). Conclusion: The present study suggests that in order to standardize the six minutes walk test, the procedure should be performed at least twice to better assess the functional capacity of patients, bearers of chronic obstructive pulmonary disease.

Keywords: Walking. Effectiveness. Lung diseases, obstrutive.

Introduction: Spirometry and analysis of blood gases data have been extensively used to assess ventilatory limitation and prognosis of COPD patients. However, functional physical tests, such as the six-minute walk test (6wt) have been used for the dynamic assessment of COPD patients. Objective: To determine correlations between respiratory function test data and the six-minute walk test in COPD patients. Patients and methods: 45 patients were submitted to clinical history survey and complete physical examination performed by the medical staff of the Pneumology Department of the Brasilia University Hospital, followed by spirometry, analysis of arterial blood gases, maximal respiratory pressures data, and the six-minute walk test. Results: Concerning the spirometric, analysis of blood gases and maximal respiratory pressures data, statistically significant positive correlations (p < 0.05) between FEV1, PaO2, SpO2, MEP and the six-minute walk test were obtained. Conclusions: For the studied group, the six minute walk test has significant correlation with FEV1, PaO2, SpO2 and MEP, and can be used as an alternative functional assessment of COPD patients.

Objective: To evaluate the applicability of the incremental (shuttle) walk test in patients with chronic obstructive pulmonary disease and compare the performance of those patients on the shuttle walk test to that of the same patients on the encouraged 6-minute walk test. Methods: A cross-sectional study was conducted, in which 24 patients with chronic obstructive pulmonary disease were selected. In random order, patients were, after an initial practice period, submitted to a shuttle walk test and an encouraged 6-minute walk test. Results: The patients obtained a higher heart rate (expressed as a percentage of that predicted based on gender and age) on the encouraged 6-minute walk test (84.1 ± 11.4%) than on the shuttle walk test (76.4 ± 9.7%) (p = 0.003). The post-test sensation of dyspnea (Borg scale) was also higher on the encouraged 6-minute walk test. On average, the patients walked 307.0 ± 89.3 meters on the shuttle walk test and 515.5 ± 102.3 meters on the encouraged 6-minute walk test (p < 0.001). There was a good correlation between the two tests in terms of the distance walked (r = 0.80, p < 0.001). Conclusion: The shuttle walk test is simple and easy to implement in patients with chronic obstructive pulmonary disease. The encouraged 6-minute walk test produced higher post-test heart rate and greater post-test sensation of dyspnea than did the shuttle walk test.

Keywords: Pulmonary disease, chronic obstructive/rehabilitation; Exercise test; Motor activity; Reproducibility of results;

Objective: To assess the effect of psychotherapy on levels of anxiety and depression, as well as on quality of life and exercise capacity in patients with chronic obstructive pulmonary disease enrolled in a pulmonary rehabilitation program. Methods: A randomized, controlled, blind clinical trial was conducted involving 49 chronic obstructive pulmonary disease patients. Patients were randomized into three groups: those submitted to the complete pulmonary rehabilitation program, which included psychotherapy and an exercise regimen (group 1); those submitted to the program minus physical exercise (group 2); and those submitted to the program minus psychotherapy (group 3). The three groups underwent a 12-week treatment program. All patients were evaluated at baseline and at completion of the pulmonary rehabilitation program through four instruments: The Beck Anxiety Inventory, Beck Depression Inventory and St. George's Respiratory Questionnaire were applied. The distance walked-weight product was also calculated. Results: Statistically significant absolute improvements in exercise capacity were found for groups 1 and 2, although not for group 3 (p = 0.007, p = 0.008 and p = 0.06, respectively). In groups 1 and 2, levels of anxiety and depressions were also significantly reduced (group 1: p = 0.0000 and p < 0.0003; group 2: p = 0.0001 and p = 0.0014), and quality of life was significantly improved (p = 0.0007 and p = 0.002, respectively). Anxiety levels were also reduced in group 3 (p = 0.03), although levels of depression were not, and quality of life was unaffected. Conclusion: Psychotherapy sessions provided as part of a pulmonary rehabilitation program assist patients with chronic obstructive pulmonary disease in coping with disease-related limitations by reducing behavioral symptoms, especially depression, thereby influencing exercise capacity and health-related quality of life.

Keywords: Pulmonary disease, chronic obstructive/rehabilitation; Pullmonary diseases, chronic obstructive/psychology; Anxiety; Depression; Quality of Life; Exercise therapy

Pulmonary thromboembolism and exacerbation of chronic obstructive pulmonary disease are common conditions. Chronic obstructive pulmonary disease is a clinical risk factor for pulmonary thromboembolism. The presentation of acute pulmonary thromboembolism and acute exacerbation of chronic obstructive pulmonary disease often mimic each other so closely that they cannot be distinguished clinically. The structural abnormalities of the lungs in chronic obstructive pulmonary disease make also difficult to interpret the results of noninvasive tests like ventilation-perfusion lung scans. Therefore, diagnosing acute pulmonary thromboembolism in patients with underlying chronic obstructive pulmonary disease is a challenging task. In order to update knowledge of the subject and offer suggestions regarding conduct, we evaluated various studies addressing this theme, including case reports and case series. In addition, we reviewed diagnostic approaches to acute pulmonary thromboembolism, and we reflect upon that topic. The clinical probability of pulmonary thromboembolism concomitant to chronic obstructive pulmonary disease is typically intermediate, as is positivity on the ventilation-perfusion lung scan. Diagnostic algorithms should take that into consideration.

Keywords: Pulmonary disease, chronic obstructive/complications; Pulmonary embolism/diagnosis; Pulmonary embolism/epidemiology; Ventilation-perfusion ratio

Introduction: The term quality of life has gained increasing importance in the scientific context. This study describes the adaptation of a disease-specific questionnaire developed by Paul Jones et al. in 1991, the St. George's Respiratory Questionnaire (SGRQ), to the Brazilian language and culture. This questionnaire evaluates the quality of life in patients with chronic obstructive pulmonary disease (COPD) and contains three domains (symptoms, activity, and impacts) divided in 76 items. The questionnaire is self-administrated, but it may be read to illiterate persons. Goal: To verify if the St. George's Respiratory Questionnaire is a valid tool to measure quality of life in patients with chronic obstructive pulmonary disease in Brazil. Methods: In order to validate the questionnaire in Brazil, it was initially translated into Portuguese and afterwards a back-translation into English, that was compared to the original version. A final Portuguese version was then written. This final version was, then, answered by 30 clinically stable COPD patients, according to the spirometry and oximetry values. Patients answered the questionnaire twice, within a 15 day interval. The length of time the patients took to answer the questionnaire and their doubts were noted. Wilcoxon test was used for the calculation of r probability between every single question between the two days; interclass correlation ratio was calculated to test the trustworthiness and reliability of the questionnaire. Results: Among the 30 participant patients, 10 were female and 20 were male. Mean age was 65.9 years. Most of the patients were found to be in stage 2 (56.7 %) of COPD, according to the American Thoracic Society classification. The interclass correlation ratio for the total score of the questionnaire was a = 0.79 and Wilcoxon p = 0.2110 (not statistically significant). The mean answering time for the two days of interview was, respectively, 11 minutes and 50 seconds and 10 minutes and 31 seconds. As concerns the doubts about the questions, the patients reported difficulties in answering Sections 4 and 5, each one of these questions written in a negative form. Conclusion: It can be concluded that the Brazilian version of the St. George's Respiratory Questionnaire is a valid and reliable tool to measure quality of life in patients with COPD in Brazil.

Keywords: obstructive lung diseases, questionnaire, quality of life, reproducibility of results, evolution studies

Objectives: To determine whether, in stable patients with chronic obstructive pulmonary disease, administration of theophylline in combination with short-acting or long-acting inhaled β2-agonists is more efficacious than is a placebo or each of these drugs used in isolation. Methods: A systematic review and meta-analysis were carried out. All randomized and double-blind clinical trials found in the literature were selected. Results: A total of eight studies were included. In comparing the effect of theophylline combined with β2-agonists to that of a placebo, we found a statistically significant improvement in mean FEV1 (0.27 L; 95%CI: 0.11 to 0.43) and mean dyspnea (-0.78; 95%CI: -1.26 to -0.29). None of the meta-analyses performed detected any difference between the results obtained using theophylline combined with β2-agonists and those obtained using β2-agonists alone. When the administration of theophylline combined with β2-agonists was compared to that of theophylline alone, there was a statistically significant improvement in mean dyspnea (-0.19; 95%CI: -0.34 to 0.04). Conclusion: In patients with stable chronic obstructive pulmonary disease, theophylline combined with β2 agonists is more efficacious than is a placebo in terms of improving FEV1 and dyspnea. In addition, theophylline combined with β2 agonists is more efficacious than is theophylline in improving dyspnea. Furthermore, administration of theophylline combined with β2 agonists is no more efficacious, for any of the variables studied, than is the use of β2-agonists in isolation.

Keywords: Lung diseases, Obstructive; Bronchodilator agents; Xanthines; Pulmonary disease, Chronic obstructive.

Objective: To describe and analyze clinical symptoms and spirometric alterations of patients with chronic obstructive pulmonary disease (COPD) and history of exposure to wood and tobacco smoke. Methods: We retrospectively evaluated data related to 170 patients distributed into 3 groups: 34 exposed only to wood smoke, 59 patients exposed only to tobacco smoke and 77 patients exposed to both. Results: The groups did not differ significantly in terms of age (p = 0.225) or degree of exposure, considering each type of exposure in isolation or in combination (p = 0.164 and p = 0.220, respectively). Females predominated in the group exposed to wood smoke. There were no differences among the groups regarding respiratory symptoms (p > 0.05), and moderate dyspnea predominated in the three groups (p = 0.141). The group exposed to wood smoke presented higher percentages of forced expiratory volume in one second/forced vital capacity ratio and of forced expiratory volume in one second (p < 0.05). Positive results on bronchodilator testing occurred more frequently in the group exposed to tobacco smoke. The percentage of severe and extremely severe obstruction was significantly higher in the group exposed to tobacco smoke (44.1%) than in that exposed to wood smoke (11.8%; p = 0.006). Conclusions: Respiratory symptoms and pulmonary function alterations consistent with COPD were observed in the groups of patients exposed to wood smoke. However, those alterations were not as significant as the alterations observed in the groups exposed to tobacco smoke. This study emphasizes the importance of prospective studies in evaluating the risk of wood-smoke-related COPD in Brazil, as well as the need for preventive measures in this area.

Keywords: Pulmonary disease, chronic obstructive; Smoking; Air pollution, indoor; Smoke.

Background: Pulmonary Rehabilitation (PR) improves the quality of life of chronic obstructive pulmonary disease (COPD) patients. However, the influence of PR on the sleep pattern of these patients is unknown. Objective: To evaluate the influence of PR on the sleep patterns of patients with COPD. Method: A total of 27 patients (22 men/5 women) were submitted to polysomnographic, gasometric and anthropometric studies before and after six weeks of PR and were evaluated using the Epworth Sleepiness Scale. The results were analyzed using paired Student's t-test, ANOVA and Newman-Keuls multiple comparison test. Results: Mean age was 63.3 5.3 years, mean FEV1 was 54.8 25.4% of predicted, mean FEV1/FVC was 49.9 12.0% of predicted, mean resting PaO2 was 69.7 7.3 mmHg, and mean resting SaO2 was 93.7 2.1%. Polysomnography revealed sleep patterns to be fragmented, with frequent waking and reduced slow-wave sleep, as well as oxygen desaturation. The most significant drops in oxygen saturation occurred during rapid eye movement sleep. No significant differences were observed between pre- and post-PR values for the other variables studied (p > 0.05).Conclusion: In the group of patients studied, PR did not alter sleep patterns.

Keywords: Sleep. Pulmonary Disease. Chronic Obstructive. Lung Diseases, rehabilitation.

Background: There is currently no consensus regarding which factors influence the quality of life of patients suffering from chronic obstructive pulmonary disease (COPD). However, identifying such factors could orient approaches to improving the quality of the lives of these patients. Objective: To evaluate factors that can interfere with quality of life in COPD patients selected for pulmonary rehabilitation. Methods: Twenty-one patients with moderate to severe COPD were evaluated. Maximal inspiratory pressure (MIP), 6-minute walk test (6MWT), body mass index (BMI), pulmonary function, blood gases, grip strength (measured with a dynamometer), quadriceps strength and St. George's Respiratory Questionnaire (SGRQ) scores were assessed. Results: Statistically significant negative correlations with quality of life were found for the following factors: "impact" scores of: forced expiratory volume in one second (FEV1) (r = -0.68; p = 0.004), FEV1 to forced vital capacity ratio (FEV1/FVC) (r = -0.61; p = 0.014), peak expiratory flow (PEF) (r = -0.53 (p = 0.015), 6MWT (r = -0.63; p = 0.001) and BMI (r = -0.64; p = 0.002); "activity" scores for: MIP (r = -0.57; p = 0.007), baseline arterial oxygen saturation by pulse oximetry (SpO2) (r = -0.52; p = 0.018) and 6MWT (r = -0.58; p = 0.007); "symptom" score for: BMI (r = -0.60; p = 0.005); and "total" scores for: FEV1 (r = -0.64; p = 0.01), PEF (r = -0.47; p = 0.033) and BMI (r = -0.57; p = 0.009). Multiple linear regression revealed the primary factors influencing quality of life to be: BMI, which presented a significant influence on "symptom", "impact" and "total" scores (p = 0.002, p = 0.009 and p = 0.024, respectively); and 6MWT, which had a significant influence on "activity" and "impact" scores (p = 0.048 and p = 0.010, respectively). Conclusions: The BMI and 6MWT were shown to have an influence on quality of life in the COPD patients studied. Therefore, therapeutic approaches to improving the quality of life of COPD patients should take these indices into consideration.

Keywords: Lung diseases, obstructive/rehabilitation. Quality of life

Objective: Making the differential diagnosis between asthma and chronic obstructive pulmonary disease (COPD) based on the response to inhaled bronchodilators by means of spirometry is controversial.The objective of this study was to identify the most useful spirometric variables in order to distinguish between asthma and COPD. Methods: Retrospective study conducted from April of 2004 to January of 2006, comparing the spirometric parameters of 103 nonsmoking patients with asthma to those of 108 patients with COPD who were smokers for more than 10 pack-years. All of the patients included in the study were older than 40 and presented stable disease at the time of the test. Results: Initial forced expiratory volume in one second (FEV1) was the same in the two groups (pre-bronchodilator FEV1 = 51%). However, patients with COPD were older (66 ± 9 years vs. 59 ± 11 years, p < 0.001) and more frequently male (73% vs. 27%, p < 0,001).After the use of the bronchodilator, the median absolute difference in FEV1 was 0.25 L (range, −0.09 to 1.13 L) in patients with asthma and 0.09 L (range, −0.1 to 0.73 L) in those with COPD (p < 0.001).The highest sensitivity (55%), specificity (91%) and likelihood ratio (6.1) for asthma diagnosis was obtained when the percentage increase in postbronchodilator FEV1 in relation to the predicted FEV1 (Δ%predFEV1) was equal to or greater than 10%.Isolated significant increases in forced vital capacity were more common in patients with COPD. Conclusions: In patients over the age of 40 and presenting obstructive lung disease, a Δ%predFEV1 ≥ 10% is the best spirometric parameter to distinguish asthma from COPD.

Keywords: Spirometry; Respiratory function tests; Lung diseases, obstructive.

Introduction: A great emphasis has been placed on health-related quality of life of COPD patients and specific questionnaires have been developed in order to measure it. Interventions directed to improve symptoms and decrease morbi-mortality may be evaluated by such questionnaires. Objective: This study describes the language and cultural adaptation of a new (and short) disease-specific health status questionnaire developed for chronic obstructive pulmonary diseases: the Airways Questionnaire 20 (AQ20). This questionnaire has only 20 simple items, and is one of the shortest ones ever described in the literature. Methods: In order to validate this questionnaire in Brazil, an initial translation from English to Portuguese has been made. The cultural adaptation was taken into consideration and then a back translation to English was undertaken, in order to obtain a final Portuguese version. Correlations were made with FEV1, SpO2, BMI and another disease specific health status questionnaire, the Saint George Respiratory Questionnaire (SGRQ), previously validated in Brazil. To test the reproducibility of AQ20, the interclass correlation ratio was done. Results: The interclass correlation ratio for the total score was a = 0.90 (intraobserver variability) and a = 0.93 (interobserver variability). The correlation with total SGRQ score was 0.76, with p < 0.001. Conclusion: It can be concluded that the Brazilian Portuguese version of AQ20 is reproducible, with good correlation with SGRQ total score, which makes it a valid questionnaire to measure health status in obstructive patients in Brazil.

Objective: To determine the nocturnal oximetry pattern in chronic obstructive pulmonary disease patients having no sleep apnea and presenting mild daytime hypoxemia, to identify probable daytime parameters capable of predicting nocturnal desaturation, and to evaluate the influence of nocturnal desaturation on the sleep pattern of these patients. Methods: Twenty-five patients were divided into two groups: those with nocturnal desaturation and those without. Results: Comparing the first group (52%) with the second, we found the following: age, 63 + 5 years versus 63 + 6 years; forced expiratory volume in the first second = 53 + 31% versus 56 + 19% predicted; ratio of forced expiratory volume in the first second to forced vital capacity, 49 + 14% versus 52 + 10%; arterial oxygen tension, 68 + 8 mmHg versus 72 + 68 mmHg; and arterial oxygen saturation, 93 + 2% versus 94 + 1%. Patients in the nocturnal desaturation group presented lower daytime arterial oxygen saturation and nocturnal arterial oxygen saturation by pulse oximetry. There was no difference between the two groups in terms of the sleep patterns observed. The ratio of forced expiratory volume in the first second to forced vital capacity was found to correlate with forced vital capacity, daytime arterial oxygen tension and daytime arterial oxygen saturation. In addition, arterial oxygen saturation by pulse oximetry during exercise was found to correlate with nocturnal arterial oxygen saturation by pulse oximetry. However, only daytime arterial oxygen saturation was predictive of nocturnal desaturation. Conclusion: The only variable capable of predicting nocturnal desaturation was daytime arterial oxygen saturation. Nocturnal desaturation did not influence the sleep patterns of patients with chronic obstructive pulmonary disease accompanied by mild daytime hypoxemia.

Keywords: Sleep, REM; Pulmonary disease, chronic obstructive; Anoxemia; Spirometry; Wakefulness

Objective: To evaluate whether a six-minute walk distance (6MWD) of < 80% of the predicted value can predict the occurrence of acute exacerbations of COPD in patients in Brazil over a 2-year period. Methods: This was a retrospective cross-sectional study involving 50 COPD patients in Brazil. At enrollment, anthropometric data were collected and patients were assessed for pulmonary function (by spirometry) and functional exercise capacity (by the 6MWD). The patients were subsequently divided into two groups: 6MWD ≤ 80% of predicted and 6MWD > 80% of predicted. The occurrence of acute exacerbations of COPD over 2 years was identified by analyzing medical records and contacting patients by telephone. Results: In the sample as a whole, there was moderate-to-severe airflow obstruction (mean FEV1 = 41 ± 12% of predicted) and the mean 6MWD was 469 ± 60 m (86 ± 10% of predicted). Over the 2-year follow-up period, 25 patients (50%) experienced acute exacerbations of COPD. The Kaplan-Meier method showed that the patients in whom the 6MWD was ≤ 80% of predicted were more likely to have exacerbations than were those in whom the 6MWD was > 80% of predicted (p = 0.01), whereas the Cox regression model showed that the former were 2.6 times as likely to have an exacerbation over a 2-year period as were the latter (p = 0.02). Conclusions: In Brazil, the 6MWD can predict acute exacerbations of COPD over a 2-year period. The risk of experiencing an acute exacerbation of COPD within 2 years is more than twice as high in patients in whom the 6MWD is ≤ 80% of predicted.

Keywords: Pulmonary disease, chronic obstructive; Risk groups; Exercise.

Depression is the most prevalent psychiatric disorder among hospitalized patients. Chronic obstructive pulmonary disease (COPD) is the most common pulmonary disease, responsible for a high incidence of hospitalization. The purpose of this study is to determine the prevalence of major depression in patients hospitalized due to COPD and correlate such depression with PaCO2, PaO2, respiratory infection, degree of functional airflow obstruction, and steroid therapy. Depression was diagnosed according to DSM IV criteria for major depressive disorders, and assessed by the Beck Depression Inventory. The interview, spirometry, and arterial blood gas analysis were performed between the third and the tenth day of hospitalization. The authors made a prospective study of 51 patients, 34 male and 17 female, with a mean age of 61 ± 11 years. Respiratory infection was the most frequent cause of hospital admission. Major depression was present in 26.9% (n = 11) of the patients, and proportionally higher in females (8 vs 3, p = 0.003). PaCO2 was higher in depressive patients than in non-depressive ones (60.1 ± 18.0 vs 45.8 ± 10.0 mmHg, p = 0.004). Other variables did not display significant differences. The authors conclude that major depression is highly prevalent among patients with COPD, specially in hypercapnic individuals and women.

Keywords: Chronic obstructive pulmonary disease. Steroid. Hypercapnia. Hypoxemia. Depression.

Objective: To compare the efficacy, safety, and tolerability of azithromycin and amoxicillin in the treatment of patients with infectious exacerbation of chronic obstructive pulmonary disease. Methods: This study was conducted at six medical centers across Brazil and included 109 patients from 33 to 82 years of age. Of those, 102 were randomized to receive either azithromycin (500 mg/day for three days, n = 49) or amoxicillin (500 mg every eight hours for ten days, n = 53). The patients were evaluated at the study outset, on day ten, and at one month. Based on the clinical evaluation of the signs and symptoms present on day ten and at one month, the outcomes were classified as cure, improvement, or treatment failure. The microbiological evaluation was made through the culture of sputum samples that were considered appropriate samples only after leukocyte counts and Gram staining. Secondary efficacy evaluations were made in order to analyze symptoms (cough, dyspnea, and expectoration) and pulmonary function. Results: There were no differences between the groups treated with azithromycin or amoxicillin in terms of the percentages of cases in which the outcomes were classified as cure or improvement: 85% vs. 78% (p = 0.368) on day ten; and 83% vs. 78% (p = 0.571) at one month. Similarly, there were no significant differences between the two groups in the secondary efficacy variables or the incidence of adverse effects. Conclusion: Azithromycin and amoxicillin present similar efficacy and tolerability in the treatment of acute exacerbation of chronic obstructive pulmonary disease.

Keywords: Amoxicillin/therapeutic use; Azithromycin/therapeutic use; Bronchitis, chronic/drug therapy;

Objective: To quantify elastic fibers (EFs) and smooth muscle (SM) cells, as well as CD4+ and CD8+ T lymphocytes, in stable chronic obstructive pulmonary disease (COPD). Methods: Surgical specimens were obtained from 15 COPD patients, 18 smokers without airflow limitation, and 14 nonsmokers. Histological and immunohistochemical methods were employed in order to quantify EFs, SM cells, CD4+ T cells, and CD8+ T cells. Results: There was no significant difference in EF numbers among the three groups (p > 0.05). The number of EFs per unit area of lung tissue (mm2) and the percentage of EFs in the lung tissue were similar among the three groups. The numbers of SM cells were found to be higher in the COPD patients than in the smokers (p = 0.003) or in the nonsmokers (p = 0.009). There was a tendency toward an increase in CD8+ T-cell counts in the COPD patients. In specimens collected from the COPD patients, CD4+ T-cell counts were lower than in those collected from the smokers (p = 0.015) or from the nonsmokers (p = 0.003). There was a weak correlation between CD4+ T-cell count and the ratio of forced expiratory volume in one second to forced vital capacity (r2 = 0.003). Conclusions: The EF counts were similar among the three groups. Hypertrophy/hyperplasia of airway wall SM cells was found in the COPD patients and in the smokers, indicating that airway remodeling occurs in smokers. The CD4/CD8 ratio was lower in the COPD patients.

Keywords: Pulmonary disease, chronic obstructive; CD4 Lymphocyte Count; Elastic tissue; Muscle, smooth.