Objective: To identify the role of bronchodilators in the maximal breath-hold time in patients with obstructive lung disease (OLD). Methods: We conducted a case-control study including patients with OLD and a control group. Spirometric tests were performed prior to and after the use of a bronchodilator, as were breath-hold tests, using an electronic microprocessor and a pneumotachograph as a flow transducer. Respiratory flow curves were displayed in real time on a portable computer. The maximal breath-hold times at end-inspiratory volume and at end-expiratory volume (BHTmaxVEI and BHTmaxVEE, respectively) were determined from the acquired signal. Results: A total of 35 patients with OLD and 16 controls were included. Prior to the use of a bronchodilator, the BHTmaxVEI was significantly lower in the OLD group than in the control group (22.27 ± 11.81 s vs. 31.45 ± 15.73 s; p = 0.025), although there was no significant difference between the two groups in terms of the post-bronchodilator values (24.94 ± 12.89 s vs. 31.67 ± 17.53 s). In contrast, BHTmaxVEE values were significantly lower in the OLD group than in the control group, in the pre- and post-bronchodilator tests (16.88 ± 6.58 s vs. 22.09 ± 7.95 s; p = 0.017; and 21.22 ± 9.37 s vs. 28.53 ± 12.46 s; p = 0.024, respectively). Conclusions: Our results provide additional evidence of the clinical usefulness of the breath-hold test in the assessment of pulmonary function and add to the existing knowledge regarding the role of the bronchodilator in this test.

Keywords: Respiratory function tests; Pulmonary disease, chronic obstructive; Bronchodilator agents; Apnea.

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

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.

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.

Background: Patients with chronic obstructive pulmonary disease usually present intolerance to physical exertion due to ventilatory limitation. L-carnitine has been used to enhance aerobic capacity in patients with chronic diseases, but no study seems to be available for this patient population. Objective: To evaluate the influence of L-carnitine supplementation (2 g/day) in chronic obstructive pulmonary disease patients undergoing physical training three times a week for six weeks. Method: Patients (mean age 69 ± 7 years, n = 30) with stable chronic obstructive pulmonary disease and < 65% of predicted forced expiratory volume in 1 second (FEV1) were separated into three groups of 10 patients each. Group 1 (G1, n = 10) received physical training and L-carnitine (2 g/day), group 2 (G2, n = 10) received physical training and placebo, and group 3 (G3, n = 10) received only L-carnitine (2 g/day). Spirometry and a 6-minute walking distance test were performed before and after intervention. Plasma levels of free carnitine were measured at the beginning and end of the study. Results: A significant increase in walking distance was found only in G1 and G2 (421 ± 100 to 508 ± 80.7 and 496 ± 78.7 to 526 ± 64.3 respectively). In addition, heart rates during physical training sessions were found to be significantly lower in G1 when compared to G2. There were no significant changes in spirometric variables, oxygen saturation or dyspnea in any group. Plasma levels of free L-carnitine were found to increase only in G3 (59.2 ± 13.8 to 102.3 ± 15.3 mmol/L). Conclusion: Oral L-carnitine supplementation combined with physical training may improve tolerance to physical exertion in chronic obstructive pulmonary disease patients.

Keywords: Chronic obstructive pulmonary disease. Carnitine/therapeutic use. Spirometry/methods. Exercise. Walking.

Objective: To evaluate whether the use of inhaled albuterol via a metered-dose inhaler with a large-volume spacer with antistatic treatment modifies the bronchodilator test results when compared with the usual technique (no spacer). Methods: A prospective study involving 24 patients, 18-45 years of age, clinically suspected of having asthma, and under treatment at the Outpatient Pulmonary Clinic of the Federal University of Minas Gerais Hospital das Clínicas, located in the city of Belo Horizonte, Brazil. All of the patients underwent two bronchodilator tests: one with and one without the use of a large-volume spacer. Results: There was no significant difference in the variation of FEV1 prior to and after bronchodilator use between the two techniques (mean FEV1 = 0.01 L; 95% CI: −0.05 to 0.06; p = 0.824). No statistically significant difference was found between the two techniques regarding the qualitative results on the bronchodilator test (p = 1.00). There was concordance between the techniques in terms of the bronchodilator test results (kappa coefficient = 0.909; p < 0.005). Conclusions: According to the results of this study, the use of large-volume spacers does not significantly modify bronchodilator test results.

Keywords: Asthma; Spirometry; Inhalation spacers.

Objective: To evaluate, using pulmonary function tests, the effectiveness of formoterol as a bronchodilator at 30 min after its administration in patients with poorly reversible COPD. Methods: A prospective study including 40 COPD patients not responding to the short-acting bronchodilator used in the spirometric test-variation of less than 200 mL and less than 7% of predicted in forced expiratory volume in one second (FEV1). All patients were classified as having stage II, III, or IV COPD (Brazilian Thoracic Society/Global Initiative for Chronic Obstructive Lung Disease) and presented FEV1 ≤ 70% of predicted value. The patients were randomized into two groups of 20, with similar clinical characteristics, receiving, via a dry powder inhaler, either formoterol or a placebo. The pulmonary function testing (plethysmography) was repeated at 30 min after formoterol or placebo administration. Results: In the formoterol group, the mean values obtained for FEV1, inspiratory capacity, and forced vital capacity were significantly greater than those obtained in the placebo group (p = 0.00065, p = 0.05, and p = 0.017, respectively), whereas that obtained for airway resistance was significantly lower (p = 0.010). Less pronounced differences were observed for residual volume, vital capacity and specific airway conductance, which were lower, higher and higher, respectively, in the formoterol group. Conclusions: In COPD patients not responding to the short-acting bronchodilator used in the spirometric test, formoterol promoted significant improvement in lung function at 30 min after of administration. Further studies are required to confirm whether formoterol can also be used as a medication for immediate relief of symptoms in COPD.

Keywords: Chronic obstructive pulmonary disease; Respiratory function tests; Bronchodilator agents.

Objective: The frequency of obstructive sleep apnea (OSA) in patients with idiopathic pulmonary fibrosis (IPF) is high. The clinical course of non-IPF interstitial lung disease (ILD) can be similar to that of IPF. We sought to assess the frequency and predictors of OSA in patients with non-IPF fibrotic ILD, as well as the impact of positive airway pressure (PAP) therapy on the quality of life of such patients. Methods: This was a prospective study in which non-IPF fibrotic ILD patients underwent a home sleep apnea test. The patients with and without OSA were compared, and a multivariate logistic regression model was used to identify independent predictors of OSA. At 3 months after initiation of PAP therapy, we evaluated the participating patients for respiratory events, nocturnal hypoxemia, and changes in quality of life. Results: Of a total of 50 patients, 50% were male, and 76% were diagnosed with OSA. The mean age was 67.8 ± 8.3 years. The patients with OSA had significantly lower TLC (p = 0.033) and awake SpO2 (p = 0.023) than did those without OSA. In the multivariate logistic regression model, SpO2 (OR = 0.46; p = 0.016) and TLC (OR = 0.95; p = 0.026) remained significantly associated with OSA risk. A total of 12 patients received PAP therapy. At 3 months after initiation of PAP therapy, 91.7% were well controlled, Epworth Sleepiness Scale scores decreased significantly (p = 0.006), and emotional well-being tended to improve (p = 0.068). PAP therapy corrected nocturnal hypoxemia in all patients. Conclusions: We found a high frequency of OSA in patients with non-IPF fibrotic ILD. A low TLC was an independent predictor of a higher risk of OSA. PAP therapy can correct nocturnal hypoxemia. There should be a low threshold for suspicion of OSA and initiation of PAP therapy in patients with non-IPF fibrotic ILD.

Keywords: Sleep apnea, obstructive; Fibrosis, pulmonary; Total lung capacity; Hypoxia; Quality of life.

Objective: To evaluate sleep-onset time variability, as well as sleep characteristics on weekday and weekend nights, in individuals with moderate-to-severe COPD. Methods: Sleep was objectively assessed by an activity/sleep monitor for seven consecutive nights in individuals with COPD. For analysis, individuals were divided into two groups according to sleep-onset time variability results, characterized by intrasubject standard deviation of sleep-onset time (SOTV) = 60 min or < 60 min. Results: The sample comprised 55 individuals (28 males; mean age = 66 ± 8 years; and median FEV1 % of predicted = 55 [38-62]). When compared with the SOTV<60min group (n = 24), the SOTV=60min group (n = 31) presented shorter total sleep time (5.1 ± 1.3 h vs. 6.0 ± 1.3 h; p = 0.006), lower sleep efficiency (73 ± 12% vs. 65 ± 13%; p = 0.030), longer wake time after sleep onset (155 ± 66 min vs. 115 ± 52 min; p = 0.023), longer duration of wake bouts (19 [16-28] min vs. 16 [13-22] min; p = 0.025), and higher number of steps at night (143 [104-213] vs. 80 [59-135]; p = 0.002). In general, sleep characteristics were poor regardless of the day of the week, the only significant difference being that the participants woke up about 30 min later on weekends than on weekdays (p = 0.013). Conclusions: Sleep-onset time varied over 1 h in a standard week in the majority of individuals with COPD in this sample, and a more irregular sleep onset indicated poor sleep quality both on weekdays and weekends. Sleep hygiene guidance could benefit these individuals if it is integrated with their health care.

Keywords: Pulmonary disease, chronic obstructive; Sleep; Actigraphy.

Background: The nucleoside adenosine is a potent vasodilator. Although its effect on the pulmonary arteries is well known, its influence on capillaries and veins has yet to be described. Objective: To evaluate the pre- and post-administration effects of adenosine on arterial and venous resistance in the pulmonary circulation of patients with primary pulmonary hypertension. Method: The study involved 7 patients with primary pulmonary hypertension and presenting a positive response to adenosine on the acute test. Before and after adenosine administration, arterial and venous resistances were determined by estimating pulmonary capillary pressure through analysis of pulmonary artery pressure decay curves. Results: Following adenosine administration, there was an increase in the cardiac index (from 1.71 ± 0.23 to 2.72 ± 0.74 L/min-1/m-2) and a decrease in pulmonary vascular resistance (from 2924 ± 1060 to 1975 ± 764 dynes/s/cm-5/m-2) with no significant variations in mean pulmonary artery pressure (pre: 75.6 ± 16.8 mmHg; post: 78.1 ± 18.8 mmHg), pulmonary wedge pressure (pre: 15.3 ± 1.5 mmHg; post: 15.4 ± 1.9 mmHg) and pulmonary capillary pressure (pre: 43.8 ± 5.8 mmHg; post: 44.5 ± 4.9 mmHg). The ratio between arterial resistance and total pulmonary vascular resistance also presented a less than significant variation (pre: 50 ± 15%; post: 49 ± 17%). These findings suggest that adenosine affects the capillaries and veins as well as the arteries. Conclusion: We can conclude that the adenosine mechanism is not restricted to the arterial aspect of the pulmonary circulation, and that analysis of pulmonary capillary pressure could prove useful in the study of various drugs that affect the pulmonary circulation.

Keywords: Key Words: Adenosine/pharmacocinetic. Adenosine/uso terapêutico. Blood pressure. Hypertension pulmonary.

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.

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

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.

Objective: Although Mycobacterium avium complex (MAC) lung disease has been shown to be associated with lung cancer and hematologic malignancies, there have been few studies of its relationships with other types of cancer. The aim of this study was to assess the effect that coexisting advanced extrapulmonary solid tumors have on the progression of MAC lung disease. Methods: This was a retrospective study of patients diagnosed with MAC lung disease, on the basis of the American Thoracic Society (ATS) criteria, between October of 2005 and March of 2019. The patients were divided into three groups: those with advanced-stage cancer (A-SC group); those with early-stage cancer (E-SC group); and those without cancer (control group). Progression of MAC lung disease was defined as exacerbation seen on imaging. Patient characteristics and the time to progression were compared among the three groups. Results: A total of 286 patients met the ATS diagnostic criteria for MAC lung disease, and 128 of those were excluded. Of the remaining 158 patients, 20 (7.0%) were in the A-SC group, 36 (12.6%) were in the E-SC group, and 102 (35.7%) were in the control group. The median time to progression in the A-SC, E-SC, and control groups was 432, 3,595, and 2,829 days, respectively (p < 0.01). A proportional hazards model showed that the significant predictors of MAC lung disease progression were advanced-stage cancer (hazard ratio [HR] = 6.096; 95% CI: 2.688-13.826; p < 0.01), cavitary lesions (HR = 2.750; 95% CI: 1.306-5.791; p < 0.01), and a high Nodule-Infiltration-Cavity-Ectasis score (HR = 1.046; 95% CI: 1.004-1.091; p = 0.033). Conclusions: A coexisting advanced extrapulmonary solid tumor could hasten the progression of MAC lung disease.

Keywords: Nontuberculous mycobacteria; Mycobacterium avium complex; Neoplasms; Radiography.

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

Objective: To study the effects of nocturnal hypoxemia in patients with chronic obstructive pulmonary disease without obstructive sleep apnea syndrome. Methods: We studied 21 patients-10 desaturators and 11 nondesaturators-submitted to arterial blood gas analysis, polysomnography, spirometry, cardiopulmonary exercise testing (cycle ergometer), and hand-grip dynamometry, as well as measurements of maximal inspiratory pressure, maximal expiratory pressure, and C-reactive protein (CRP) levels. Patients with arterial oxygen tension > 60 mmHg were included; those with an apnea-hypopnea index > 5 events/hour of sleep were excluded. Maximal oxygen uptake, maximal power, systolic blood pressure, diastolic blood pressure (DBP), and maximal heart rate were measured during exercise in order to detect hemodynamic alterations. Patients presenting CRP levels above 3 mg/L were considered CRP-positive. Results: Minimal peripheral oxygen saturation during sleep was significantly higher among nondesaturators (p = 0.03). More desaturators presented CRP > 3 mg/L (p < 0.05). No differences were observed in terms of any variables, However, mean peripheral oxygen saturation during sleep correlated with DBP and maximal inspiratory pressure (p < 0.001 and p = 0.001, respectively). Conclusions: Although nocturnal hypoxemia does not reduce exercise capacity or hand-grip strength in patients with mild/moderate COPD, its effect on maximal exercise DBP seems to depend on the degree of hypoxemia. In addition, there is a positive relationship between maximal inspiratory pressure and mean peripheral oxygen saturation during sleep, as well as evidence of pronounced inflammatory activation in patients with nocturnal hypoxemia.

Keywords: Pulmonary disease, chronic obstructive; Exercise test; Anoxia; Respiratory function tests.

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.