Background: Obesity can effect the thorax, diphragm and abdominal muscles, thereby resulting in altered respiratory function. Objective: To evaluate the effects of obesity and to determine whether body mass index (BMI) and waist circumference correlate with spirometry values in obese individuals. Method: We studied 96 non-smokers of both sexes, 48 suffering from class I and class II obesity and ranging in age rom 18 to 75. All participants presented a BMI between 30 kg/m2 and 40 kg/m2 and none had a history of morbidity. Spirometry was performed, and waist circumferences were measured. Results: No significant differences were found between the spirometric values of men with class I or II obesity and those of non-obese men. In obese women, forced vital capacity and forced expiratory volume in one second (FEV1) were significantly lower than in women who were not obese. Obese individuals of both sexes presented significantly lower expiratory reserve volume (ERV) than did non-obese individuals. Although inspiratory capacity was greater in obese men and women, the difference was significant only for the men. In obese men, there was a significant negative correlation, not seen in the women, between waist circumference and FEV1. Conclusion: Pulmonary function is altered in women suffering from class I and II obesity. In obese men, although pulmonary function is unaffected by BMI, we observed a significant negative correlation between BMI and ERV. We can conclude that pulmonary function is influenced by waist circumference in men suffering from class I and II obesity.

Keywords: Respiratory function tests. Spirometry. Body mass index. Obesity.

Objective: To investigate dyspnea in individuals with Class II or III obesity and look for correlations among the respiratory data related to such individuals. Methods: This study involved 49 subjects with a body mass index >35 kg/m2, divided into two groups (those with dyspnea and those without). The baseline dyspnea index was evaluated, as were spirometry findings, maximal respiratory pressures and arterial blood gas analysis. Results: Of the 49 subjects evaluated, 37 reported dyspnea and 12 reported no dyspnea. The baseline dyspnea index differed between the two groups. The mean values were within the range of normality for all subjects and all parameters, except for the following: ratio of residual volume to total lung capacity; expiratory reserve volume; and the alveolar-arterial oxygen gradient. The subjects with dyspnea presented significantly lower values for expiratory reserve volume, maximal expiratory pressure and arterial pH. In all subjects, body mass index correlated significantly with the following: baseline dyspnea index; the residual volume/total lung capacity ratio; the forced expiratory volume in one second/forced vital capacity ratio; forced expiratory flow between 25% and 75% of forced vital capacity; arterial oxygen tension; the alveolar-arterial oxygen gradient; and arterial carbon dioxide tension. The baseline dyspnea index was found to correlate significantly with the following parameters: residual volume/total lung capacity ratio; expiratory reserve volume; arterial oxygen tension; the alveolar-arterial oxygen gradient; and arterial carbon dioxide tension. Conclusion:  Dyspnea is a common complaint in individuals with class II or III obesity. Such individuals present a pronounced reduction in expiratory reserve volume and an increase in the alveolar-arterial oxygen gradient. The correlations found suggest that obese individuals present dysfunction of the lower airways, and that obesity itself plays a role in the genesis of dyspnea.

Keywords: Obesity/complications; Dyspnea/epidemiology; Dyspnea/physiopathology; Respiratory function tests

Objective: To identify respiratory symptoms and evaluate lung function in mine workers. Methods: This was a cross-sectional observational study involving production sector workers of a pyrochlore mining company. The subjects completed the British Medical Research Council questionnaire, which is designed to evaluate respiratory symptoms, occupational exposure factors, and smoking status. In addition, they underwent pulmonary function tests with a portable spirometer. Results: The study involved 147 workers (all male). The mean age was 41.37 ± 8.71 years, and the mean duration of occupational exposure was 12.26 ± 7.09 years. We found that 33 (22.44%) of the workers had respiratory symptoms and that 26 (17.69%) showed abnormalities in the spirometry results. However, we found that the spirometry results did not correlate significantly with the presence of respiratory symptoms or with the duration of occupational exposure. Conclusions: The frequencies of respiratory symptoms and spirometric changes were low when compared with those reported in other studies involving occupational exposure to dust. No significant associations were observed between respiratory symptoms and spirometry results.

Keywords: Spirometry; Mining; Niobium; Occupational exposure.

Objective: To compare clinical and pathological staging in patients with non-small cell lung cancer submitted to surgical treatment, as well as to identify the causes of discordance. Methods: Data related to patients treated at the Department of Thoracic Surgery of the Pontifical Catholic University of Rio Grande do Sul São Lucas Hospital were analyzed retrospectively. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated for clinical stages IA, IB, and IIB. The kappa index was used to determine the concordance between clinical and pathological staging. Results: Of the 92 patients studied, 33.7% were classified as clinical stage IA, 50% as IB, and 16.3% as IIB. The concordance between clinical and pathological staging was 67.5% for stage IA, 54.3% for IB, and 66.6% for IIB. The accuracy of the clinical staging was greater for stage IA, and a kappa of 0.74, in this case, confirmed a substantial association with pathological staging. The difficulty in evaluating nodal metastatic disease is responsible for the low concordance in patients with clinical stage IB. Conclusions: The concordance between clinical and pathological staging is low, and patients are frequently understaged (in the present study, only one case was overstaged). Strategies are necessary to improve clinical staging and, consequently, the treatment and prognosis of patients with non-small cell lung cancer.

Keywords: Neoplasm staging; Lung neoplasms/diagnosis; Lung neoplasms/surgery; Prognosis.

Objective: To correlate semiquantitative evaluation of intrapulmonary vascular dilatations (IPVD) with quantitative evaluation of shunt levels, as well as to describe clinical and pulmonary function findings in a sample of liver disease patients with IPVD. Methods: Patients presenting transthoracic echocardiography (TTE) positivity for IPVD underwent clinical evaluation, pulmonary function tests and pulmonary shunt quantification (scintigraphy with technetium-99m-labeled macroaggregated albumin and blood gas analysis after pure oxygen breathing). Results: A total of 28 liver cirrhosis patients were studied (mean age, 47.5 years; 60.7% were Child-Pugh class B). A 4-point, ascending scale was used as a measure of IPVD intensity, which was scored as 1, 2, 3 and 4, respectively, in 13 (46.4%), 9 (32.1%), 2 (7.1%) and 4 (14.3%) of the patients. Patients were divided into a low-intensity group (scores 1 and 2) and a high-intensity group (scores 3 and 4). The mean shunt assessed using scintigraphy was 14.9% in the sample as a whole and was lower in the low-intensity group (11.7% vs. 26.3%; p = 0.01). The mean shunt by blood gas analysis was higher in the high-intensity group (8.3% vs. 16.3%; p < 0.001). Mean PaO2 was lower in the high-intensity group. There was a negative correlation between DLCO and IPVD severity (r = −0.406, p = 0.01). Conclusions: TTE is a safe, useful tool for assessing IPVD severity in liver disease patients. The IPVD intensity assessed using TTE correlated with the intrapulmonary shunt values obtained through the quantitative methods evaluated, as well as with pulmonary gas exchange abnormalities.

Keywords: Anoxia; Liver cirrhosis; Hepatopulmonary syndrome; Echocardiography.

Objective: To evaluate lung function and inspiratory muscle strength, correlating them with exercise tolerance, in obese individuals with obstructive sleep apnea syndrome (OSAS). Methods: The sample comprised 31 adult subjects with moderate-to-severe OSAS diagnosed by polysomnography. We used spirometry to measure FVC, FEV1, and FVC/FEV1 ratio, using pressure manometry to measure MIP and MEP. The incremental shuttle walk test (ISWT) and the six-minute walk test (6MWT) were used in order to determine functional exercise capacity. Results: In this sample, the mean values for FVC (% of predicted), FEV1 (% of predicted): MIP, and MEP were 76.4 ± 12.3%, 80.1 ± 6.3%, 60.0 ± 21.9 cmH2O, and 81.3 ± 22.2 cmH2O, respectively. The mean distances covered on the ISWT and 6MWT were 221 ± 97 m and 480.8 ± 67.3 m, respectively. The ISWT distance showed moderate positive correlations with FVC (r = 0.658; p = 0.001) and FEV1 (r = 0.522; p = 0.003). Conclusions: In this sample of obese subjects with untreated OSAS, lung function, inspiratory muscle strength, and exercise tolerance were all below normal. In addition, we found that a decline in lung function, but not in respiratory muscle strength, was associated with exercise tolerance in these patients.

Keywords: Sleep apnea syndromes; Exercise tolerance; Respiratory function tests; Respiratory muscles.

Objective: To determine the lung age of patients with morbid obesity and to compare it with the chronological age of these patients, emphasizing the premature damage that morbid obesity does to the lungs. Methods: An open, prospective cross-sectional study comprising 112 individuals: 78 patients with morbid obesity (study group); and 34 non-obese individuals with normal pulmonary function results (control group). All of the patients underwent spirometry for the determination of lung age. The lung age and the chronological age of the individuals in each group were compared in isolation and between the two groups. Results: The difference between lung age and chronological age in the group with morbid obesity was significant (p < 0.0001; 95% CI: 6.6-11.9 years), the mean difference being 9.1 ± 11.8 years. The difference between the study group and the control group in terms of lung age was significant (p < 0.0002; 95% CI: 7.5-16.9 years), the mean difference being 12.2 ± 2.4 years. Lung age correlated positively with chronological age and body mass index (BMI), whereas it correlated negatively with the spirometric variables (p < 0.0001 for all). Multiple linear regression analysis identified BMI and chronological age (p < 0.0001) as significant predictors of lung age. Conclusions: Lung age is increased in patients with morbid obesity, suggesting premature damage and accelerated lung aging, as evidenced by the discrepancy between chronological age and lung age. The determination of lung age might become a new tool for understanding pulmonary function results, for patients as well as for health professionals, in relation to obesity control.

Keywords: Spirometry; Obesity, morbid; Respiratory function tests.

Objective: To analyze the clinicopathological aspects of bronchioloalveolar carcinoma (BAC) and the survival in a sample of patients at clinical stage I. Methods: A retrospective study involving 26 patients diagnosed with clinical stage I BAC and undergoing surgery at the Thoracic Diseases Institute of the Federal University of Rio de Janeiro, in the city of Rio de Janeiro, Brazil, between 1987 and 2007. We analyzed clinicopathological and radiological aspects, as well as mortality and survival. The data, which were collected from the medical charts of the patients, were statistically analyzed. Results: Females predominated (n = 16). The mean age at diagnosis was 68.5 years. Most patients were active smokers (69.2%). The most common forms of presentation of BAC were the asymptomatic form (84.6%) and the nodular form (88.5%). Involvement of the upper lobes predominated (57.7%). Stage IB was the most common pathological stage, followed by stages IA and IIB (46.2%, 38.4% and 15.4%, respectively). There was no in-hospital mortality. Four patients died during the postoperative follow-up, with a mean disease-free survival time of 21.3 months. The overall five-year survival rate was 83%. The probability of survival for the patients diagnosed after 1999 showed a trend toward an increase when compared with that for those diagnosed up through 1999 (three-year survival rate: 92% vs. 68%; p = 0.07). Conclusions: The clinicopathological aspects of this study sample were similar to those of patients with BAC evaluated in previous studies.

Keywords: Adenocarcinoma, bronchiolo-alveolar; Carcinoma, non-small-cell lung; Lung; Smoking.

Objective: To assess respiratory system impedance (Zrs) and spirometric parameters in children and adolescents with and without a history of preterm birth. Methods: We evaluated a sample of 51 subjects between 11 and 14 years of age: 35 who had a history of preterm birth (preterm group) and 16 who had been born at term (full-term group). Lung function was measured by spirometry, spectral oscillometry, and intra-breath oscillometry. Results: Neither spirometry nor spectral oscillometry revealed any statistically significant differences between the preterm and full-term groups. However, intra-breath oscillometry demonstrated significant differences between the two groups in terms of the change in resistance, reactance at end-inspiration, and the change in reactance (p < 0.05 for all). Conclusions: Our findings suggest that abnormalities in Zrs persist in children and adolescents with a history of preterm birth and that intra-breath oscillometry is more sensitive than is spectral oscillometry. Larger studies are needed in order to validate these findings and to explore the impact that birth weight and gestational age at birth have on Zrs later in life.

Keywords: Oscillometry; Premature birth; Respiratory function tests; Respiratory mechanics; Spirometry.

Objective: To evaluate the effects that pulmonary resection has on pulmonary function and quality of life (QoL) in patients with primary or metastatic lung cancer. Methods: This was a prospective cohort study involving all patients submitted to pulmonary resection for cancer between September of 2006 and March of 2007 at the A. C. Camargo Hospital in São Paulo, Brazil. Patients underwent spirometry in the preoperative period and at six months after the surgical procedure. After a postoperative period of six months, the patients completed an overall QoL questionnaire (the Medical Outcomes Study 36-item Short-form Health Survey) and another one, specific for respiratory symptoms (the Saint George's Respiratory Questionnaire). The scores obtained in our study were compared with those previously obtained for a general population and for a population of patients with COPD. Results: We included 33 patients (14 males and 19 females), ranging in age from 39 to 79 years. All of the patients, smokers and nonsmokers alike, presented significant worsening of pulmonary function. The mean scores on the overall QoL questionnaire were approximately 5% lower than those obtained for the general population. The scores of various domains of the symptom-specific QoL questionnaire were 50-60% lower than those obtained for the general population and approximately 20% higher than those obtained for the population with COPD. Conclusions: Pulmonary resection has a direct negative impact on pulmonary function and QoL, especially on the QoL related to aspects directly linked to pulmonary function. We highlight the importance of preoperative assessment of pulmonary function in patients undergoing pulmonary resection, in order to predict their postoperative evolution.

Keywords: Thoracic surgery; Lung neoplasms/surgery; Spirometry; Quality of life; Questionnaires.

Objective: To evaluate alterations in pulmonary function in patients with systemic sclerosis-associated interstitial pneumonia over a five-year period. Methods: This was a longitudinal study involving 35 nonsmoking patients with systemic sclerosis and without a history of lung disease. At the first evaluation, performed at the time of the diagnosis of interstitial pneumonia, the patients were submitted to HRCT, spirometry, and measurement of DLCO. The patients were subdivided into two groups by the presence or absence of honeycombing on the HRCT scans. Approximately five years after the first evaluation, the patients were submitted to spirometry and measurement of DLCO only. Results: Of the 35 patients, 34 were women. The mean age was 47.6 years. The mean time between the two evaluations was 60.9 months. Honeycombing was detected on the HRCT scans in 17 patients. In the sample as a whole, five years after the diagnosis, FVC, FEV1 and DLCO significantly decreased (81.3 ± 18.2% vs. 72.1 ± 22.2%; 79.9 ± 17.8% vs. 72.5 ± 20.6%; and 74.0 ± 20.5% vs. 60.7 ± 26.8%, respectively; p = 0.0001 for all), and the FEV1/FVC ratio significantly increased (98.5 ± 7.2% vs. 101.9 ± 7.8%; p = 0.008). In the same period, FVC, FEV1, and DLCO values were significantly lower in the patients with honeycombing on the HRCT scans than in those without (p = 0.0001). Conclusions: In systemic sclerosis-associated interstitial lung disease, the detection of honeycombing on HRCT is crucial to predicting accelerated worsening of pulmonary function.

Keywords: Scleroderma, systemic; Respiratory function tests; Tomography, X-ray computed.

Objective: To evaluate the accuracy of bacteriological methods and of polymerase chain reaction (with primers specific for IS6110 of the Mycobacterium tuberculosis complex) in testing sputum samples from indigenous (Amerindian) and non-indigenous patients. Methods: A total of 214 sputum samples (154 from indigenous patients and 60 from non-indigenous patients) were analyzed in order to determine the accuracy of smear microscopy (direct and concentrated versions) for acid-fast bacilli, culture, and polymerase chain reaction. Results: Both microscopy methods presented low sensitivity in comparison with culture and polymerase chain reaction. Specificity ranged from 91% to 100%, the concentrated acid-fast smear technique being the least specific. Nontuberculous mycobacteria were isolated three times more frequently in samples from indigenous patients than in those from non-indigenous patients. False-positive and false-negative polymerase chain reaction results were more common in the indigenous population. Conclusion: Positivity and isolation of nontuberculous mycobacteria in the acid-fast smear in conjunction with polymerase chain reaction positivity raise the following hypotheses: nontuberculous mycobacteria species with DNA regions homologous to, or even still possessing, the M. tuberculosis IS6110 exist in the Amazon; colonization of the oropharynx or of a tuberculous lesion accelerates the growth of the nontuberculous mycobacteria present in the sputum samples, making it impossible to isolate M. tuberculosis; A history of tuberculosis results in positivity for M. tuberculosis DNA. The absence of bacteriological positivity in the presence of polymerase chain reaction positivity raises questions regarding the inherent technical characteristics of the bacteriological methods or regarding patient history of tuberculosis.

Keywords: Tuberculosis, pulmonary/diagnosis; Mycobacterium tuberculosis, Polymerase chain reaction/methods; Indians, south american

Objective: To evaluate the magnitude of diurnal changes in the parameters of pulmonary function and respiratory muscle strength/endurance in a sample of patients with COPD. Methods: A group of 7 patients underwent spirometry, together with determination of MIP and MEP, at two distinct times (between 8:00 and 8:30 a.m. and between 4:30 and 5:00 p.m.) on a single day. Between assessments, the patients remained at rest in the laboratory. Results: In accordance with the Global Initiative for Chronic Obstructive Pulmonary Disease staging system, COPD was classified as moderate, severe, and very severe in 1, 3, and 3 of the patients, respectively. From the first to the second assessment, there were significant decreases in FVC, FEV1, and MEP (of 13%, 15%, and 10%, respectively), as well as (less than significant) decreases in PEF, MIP, and maximal voluntary ventilation (of 9%, 3%, and 11%, respectively). Conclusions: In this sample of COPD patients, there were diurnal variations in the parameters of pulmonary function and respiratory muscle strength. The values of FEV1, FVC, and MEP were significantly lower in the afternoon than in the morning.

Keywords: Pulmonary disease, chronic obstructive; Respiratory function tests; Respiratory muscles.

Emphysema is a condition of the lung, characterized by the abnormal increase in the size of the airspace distal to the terminal bronchioles. Currently, emphysema is the fourth leading cause of death in the USA, affecting 14 million people. The present article describes the principal tools in the imaging diagnosis of emphysema, from the early days until the present. We describe traditional techniques, such as chest X-ray, together with the evolution of computed tomography (CT) to more advanced forms, such as high resolution CT, as well as three-dimensional CT densitometry and volumetric assessment.

Keywords: Emphysema; Radiology; Tomography, X-Ray computed; Radiography, thoracic.

Objective: To evaluate whether anthropometric and dietary intake indicators are predictors of pulmonary function in cystic fibrosis (CF) patients. Methods: This was a cross-sectional study involving 69 patients (age range, 5.4-16.5 years) diagnosed with CF under follow-up at the Hospital de Clínicas de Porto Alegre, located in the city of Porto Alegre, Brazil. Anthropometric assessment was based on body mass index (BMI), mid-arm muscle circumference (MAMC), and triceps skinfold thickness (TST). Dietary intake was assessed by using recall data, which were compared with the recommended dietary allowances. Pulmonary function was assessed by ventilatory capacity, expressed as FEV1. Prevalence ratios for the outcome studied (FEV1 < 80% of predicted) were calculated by indicator. Results: In patients with MAMC and TST below the 25th percentile, the prevalence of FEV1 < 80% of predicted was significantly higher than in those with higher MAMC and TST (p < 0.001 and p = 0.011, respectively). In comparison with other patients, those with a BMI below the 50th percentile showed a 4.43 times higher prevalence of FEV1 < 80% of predicted (95% CI: 1.58-12.41), and that prevalence was 2.54 times higher in those colonized with methicillin-resistant Staphylococcus aureus (MRSA) than in those not so colonized (95% CI: 1.43-4.53). The association between dietary intake and the prevalence of FEV1 < 80% of predicted was of only borderline significance (95% CI: 0.95-3.45). Conclusions: Not being colonized with MRSA and having a BMI above the 50th percentile appear to preserve pulmonary function in CF patients.

Keywords: Cystic fibrosis; Respiratory function tests; Nutrition assessment; Energy intake.