Background: Dyspnea is a symptom that is difficult to evaluate, especially in occupational diseases. Objective: To evaluate the relationship between chronic dyspnea, in its varying degrees of severity, and the functional repercussions for dysfunction or incapacitation in former workers with asbestosis. Method: A total of 40 former workers diagnosed with asbestosis were evaluated. Dyspnea scores were determined using the modified Medical Research Council scale, the 1984 and 1993 American Medical Association scales, and the Baseline Dyspnea Index. Spirometry, measurement of diffusion capacity for carbon monoxide and cardiopulmonary exercise tests (incremental and submaximal) were also performed. Results: Based on scores obtained using the Medical Research Council and 1984 American Medical Association scales, respectively, 72.5% and 67.5% of the subjects were classified as dyspneic, compared with 37.5% and 31.6%, respectively, using the 1993 American Medical Association and Baseline Dyspnea Index scales. There was greater concordance between the Medical Research Council and 1993 American Medical Association scales, as well as between the 1984 and 1993 American Medical Association scales, when the categories of "absent" and "mild" were grouped. No significant relation was found between dyspnea, as determined by each of the scales, and functional abnormalities - either at rest or during exercise. Conclusion: In individuals with asbestosis, the degree of concordance among the available dyspnea scales varies significantly. There is a real need for dyspnea indices that evaluate respiratory dysfunction at rest and during exercise.

Keywords: Asbestosis/diagnosis. Dyspnea/physiopathology. Spirometry/methods.

Objective: To determine the prevalence and duration of social security benefit (SSB) claims granted to registered workers with asthma in Brazil by the Brazilian National Institute of Social Security in 2008. Methods: This was a retrospective, descriptive study, based on information obtained from the Brazilian Unified Benefit System database, on the number of SSB claims granted to registered workers with asthma in 2008. The reference population was the monthly mean number of workers registered in the Brazilian Social Registry Database in 2008. The variables studied were type of economic activity, gender, age, and type/duration of the SSB allowance. The relationship between work and asthma was evaluated by the prevalence ratio (PR) between work-related and non-work-related SSB claims for asthma. Results: In 2008, 2,483 SSB claims were granted for asthma, with a prevalence of 7.5 claims per 100,000 registered workers. The prevalence was higher among females than among males (PR = 2.1 between the sexes). Workers  40 years of age were 2.5 times more likely to be granted an SSB allowance for asthma than were younger workers. The prevalence was highest among workers engaged in the following types of economic activity: sewage, wood and wood product manufacturing, and furniture manufacturing (78.8, 22.4, and 22.2 claims/100,000 registered workers, respectively). The median (interquartile range) duration of SSB claims for asthma was 49 (28-87) days. Conclusions: Asthma is a major cause of sick leave, and its etiology has a strong occupational component. This has a major impact on employers, employees, and the social security system. Being female, being  40 years of age, and working in the areas of sewage, wood and wood product manufacturing, and furniture manufacturing increase the chance of sick leave due to asthma.

Keywords: Asthma; Social security; Prevalence; Occupational exposure; Occupational health.

Objective: To evaluate diaphragmatic mobility in relation to lung function, respiratory muscle strength, dyspnea, and physical activity in daily life (PADL) in patients with COPD. Methods: We included 25 patients with COPD, classified according to the Global Initiative for Chronic Obstructive Lung Disease criteria, and 25 healthy individuals. For all of the participants, the following were evaluated: anthropometric variables, spirometric parameters, respiratory muscle strength, diaphragmatic mobility (by X-ray), PADL, and the perception of dyspnea. Results: In the COPD group, diaphragmatic mobility was found to correlate with lung function variables, inspiratory muscle strength, and the perception of dyspnea, whereas it did not correlate with expiratory muscle strength or PADL. Conclusions: In patients with COPD, diaphragmatic mobility seems to be associated with airway obstruction and lung hyperinflation, as well as with ventilatory capacity and the perception of dyspnea, although not with PADL.

Keywords: Pulmonary disease, chronic obstructive; Diaphragm; Spirometry; Dyspnea; Maximal respiratory pressures.

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: 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 determine the prevalence of temporary social security benefits due to respiratory disease granted to employees, as well as the number of lost workdays and costs resulting from those in Brazil between 2003 and 2004. Methods: Cross-sectional study using data obtained from the Unified System of Benefits of the Brazilian Institute of Social Security (INSS, Instituto Nacional de Seguro Social) and the Brazilian Social Registry Database. Data regarding gender, age, diagnosis and type of economic activity, as well as type, duration and cost of benefits, were compiled. Results: Respiratory diseases accounted for 1.3% of the total number of temporary social security benefits granted by INSS, with a prevalence rate of 9.92 (per 10,000 employment contracts). Females and individuals older than 50 years of age were the most affected. Non-work-related benefits were more common than were work-related benefits. The most prevalent diseases were pneumonia, asthma and COPD, followed by laryngeal and vocal cord diseases. The most prevalent types of economic activity were auxiliary transportation equipment manufacturing, tobacco product manufacturing and computer-related activities. The mean duration of benefits was 209.68 days, with a mean cost of R$ 4,495.30 per occurrence. Respiratory diseases caused by exogenous agents demanded longer sick leave (mean, 296.72 days) and greater cost (mean, R$ 7,105.74). Conclusions: The most prevalent diseases were airway diseases and pneumonia. Workers from auxiliary transportation equipment manufacturing, tobacco product manufacturing and computer-related activities were the most affected. Diseases caused by exogenous agents demanded longer sick leaves and resulted in greater costs.

Keywords: Respiratory tract diseases; Sick leave; Work; Workers' compensation; Social security.

Objective: To evaluate pulmonary function and respiratory muscle strength in chronic renal failure patients, correlating these variables with hemodialysis-related weight fluctuation; to study the correlation between the duration of hemodialysis and potential respiratory alterations. Methods: Seventeen patients (median age, 47 years; interquartile range, 41-52 years), submitted to three weekly hemodialysis sessions for a median of 27 months (interquartile range, 14-55) were evaluated. Twelve of the patients were male. The patients underwent spirometry. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were measured prior to and after the first hemodialysis session of the week. Body weight was quantified prior to and after each of the three weekly sessions. Results: Before the first hemodialysis session of the week, 8 patients presented mild restrictive defect, which normalized after the session in 2 of those patients. After dialysis, there was a significant increase in forced vital capacity (p = 0.02) and a significant decrease in body weight (p = 0.0001). Weight fluctuation over 3 days without hemodialysis tended to correlate with the variation in forced vital capacity in the first weekly session (r = 0.47; p = 0.055). Duration of hemodialysis correlated with predialysis MIP (r = −0.3; p = 0.03) and MEP (r = −0.63; p = 0.006). Conclusions: More pronounced weight gain in the interdialytic period is associated with worsening of lung function, which is almost fully reversible by hemodialysis. In addition, longer duration of hemodialysis is associated with decreased respiratory muscle strength.

Keywords: Spirometry; Respiratory muscles/physiopathology; Kidney failure, chronic; Renal dialysis.

The prevalence of respiratory symptoms in populations at risk or in populations not at risk is an indirect indicator of acute and chronic respiratory diseases, with a high grade of confidence from an epidemiological point of view. In order to contribute to this, the authors carried out a prevalence study among workers with occupational exposure to silica dust in a marble plant. The authors selected workers who worked with hard granite stone, slate and marble. Workers were submitted to a standardized questionnaire and 84 people were studied. All were male, mean age was (± SD) 26.2 (± 7.4 years), and had had short time of exposure to dust (52 workers worked less than 5 years in the marble industry). Thirty-four were smokers (10.0 (± 2.3) pack years), 9 former smokers, and 41 non-smokers. Twenty-four had cough, 30 sputum, 1 dyspnea grade III, 5 wheezing. Thirty-eight presented at least one of the studied respiratory symptoms and 9 presented chronic bronchitis. The lung function evaluated in 82 workers through spirometry was normal in 78 of the cases and an obstructive pattern was detected in 4 of them. A significant statistical association between chronic bronchitis and exposure time to stone dust was found (OR = 5.37; 95% CI = 1.01-28.74). However, that association was lost after other factors, such as cigarette smoking and age, were evaluated (OR = 1.21; 95% CI = 0.12-11.93). The association between smoking and bronchitis (OR = 14.18; 95% CI = 1.80-111.62) remained marginally significant even after controlling exposure time to stone dust and age (OR = 6.34; 95% CI = 0.76-52.94). Results suggest that among the marble industry workers studied, the prevalence of chronic bronchitis is more strongly associated to smoking to with exposure time to stone dust.

To describe the intra-rater and inter-rater reliability of the Brazilian Portuguese version of the fatigue severity scale (FSS) in patients with COPD and to identify the presence of its association with parameters of pulmonary function, dyspnea, and functional capacity. Methods: This was an observational cross-sectional study involving 50 patients with COPD, who completed the FSS in interviews with two researchers in two visits. The FSS scores were correlated with those of the Medical Research Council (MRC) scale, as well as with FEV1, FVC, and six-minute walk distance (6MWD). Results: The mean age of the patients was 69.4 ± 8.23 years, whereas the mean FEV1 was 46.5 ± 20.4% of the predicted value. The scale was reliable, with an intraclass correlation coefficient of 0.90 (95% CI, 0.81-0.94; p < 0.01). The FSS scores showed significant correlations with those of MRC scale (r = 0.70; p < 0.01), as well as with 6MWD (r = −0.77; p < 0.01), FEV1 (r = −0.38; p < 0.01), FVC (r = −0.35; p < 0.01), and stage of the disease in accordance with the Global Initiative for Chronic Obstructive Lung Disease criteria (r = 0.37; p < 0.01). Conclusions: The Brazilian Portuguese version of the FSS proved reliable for use in COPD patients in Brazil and showed significant correlations with sensation of dyspnea, functional capacity, pulmonary function, and stage of the disease.

Keywords: Fatigue; Pulmonary disease, chronic obstructive; Reproducibility of results; Validation studies.

Background: The primary work-related lung disease in Brazil is silicosis. Its pathogenic agent is the dust of crystalline free silica (SiO2; silicon dioxide). The inflammatory process of silicosis is not yet well understood. Objective: To analyze, through immunologic laboratory evaluation, including nonspecific and specific immunity, the profile of IgG, IgM, IgA, C3, C4 and autoantibodies in the serum of workers, with or without silicosis, exposed to silica. Methods: Fifty-eight male workers were studied. All had been exposed to silica. Immunologic, radiologic and functional evaluations were made. The immunoglobulins IgG, IgA, and IgM, the complement system components C3 and C4, and the autoantibodies were assessed. Results: Chest X-rays were normal in 20 of the 58 workers and compatible with silicosis in 38. Among the 38 who were positive, IgG values were, on average, higher than in the group with normal X-rays (p < 0.05). There were no significant differences in average values of IgA, IgM, C3 or C4 (p > 0.05). The percentage of autoantibody positivity was higher in the silicosis group than in the group with normal X-rays. Conclusion: The increased levels of IgG in patients with silicosis constitutes an important discovery. It may represent continuity of the granulomatous reaction, even when the individual is no longer being exposed to silica. However, further studies are necessary in order to increase understanding of the mechanism involved in the silicosis immunologic process.

Keywords: Lung diseases. Silicosis. Occupational diseases. Immunoglobulins

Objective: To investigate the usefulness of descriptive terms applied to the sensation of dyspnea (dyspnea descriptors) that were developed in English and translated to Brazilian Portuguese in patients with four distinct clinical conditions that can be accompanied by dyspnea. Methods: We translated, from English to Brazilian Portuguese, a list of 15 dyspnea descriptors reported in a study conducted in the USA. Those 15 descriptors were applied in 50 asthma patients, 50 COPD patients, 30 patients with heart failure, and 50 patients with class II or III obesity. The three best descriptors, as selected by the patients, were studied by cluster analysis. Potential associations between the identified clusters and the four clinical conditions were also investigated. Results: The use of this set of descriptors led to a solution with nine clusters, designated expiração (exhalation), fome de ar (air hunger), sufoco (suffocating), superficial (shallow), rápido (rapid), aperto (tight), falta de ar (shortness of breath), trabalho (work), and inspiração (inhalation). Overlapping of the descriptors was quite common among the patients, regardless of their clinical condition. Asthma, COPD, and heart failure were significantly associated with the inspiração cluster. Heart failure was also associated with the trabalho cluster, whereas obesity was not associated with any of the clusters. Conclusions: In our study sample, the application of dyspnea descriptors translated from English to Portuguese led to the identification of distinct clusters, some of which were similar to those identified in a study conducted in the USA. The translated descriptors were less useful than were those developed in Brazil regarding their ability to generate significant associations among the clinical conditions investigated here.

Keywords: Dyspnea; Pulmonary disease, chronic obstructive; Asthma; Heart failure.

Abstract Objective: To determine the validity and reproducibility of two subjective instruments to assess limitations in activities of daily living (ADLs) in patients with chronic obstructive pulmonary disease (COPD) in Brazil: the Pulmonary Functional Status and Dyspnea ­Questionnaire ‑ ­Modified version (PFSDQ-M) and the Medical Research Council (MRC) scale. Methods: Thirty patients with COPD (age, 67 ± 10 years; males, 17; forced expiratory volume in one second, 42% ± 13% of predicted) completed the Portuguese-language versions of the two instruments on two occasions, one week apart. The PFSDQ-M has three components: influence of dyspnea on ADLs, influence of fatigue on ADLs and change experienced by the patient with ADLs. The MRC scale is simple, with only five items, in which patients report the degree to which dyspnea limits their performance of ADLs. The traditional Saint George's Respiratory Questionnaire (SGRQ), previously validated for use in Brazil, was used as a validation criterion. Results: The test-retest reliability (intraclass correlation coefficient) of the PFSDQ-M was 0.93, 0.92 and 0.90 for the dyspnea, fatigue and change components, respectively, compared with 0.83 for the MRC scale. Bland-Altman plots showed good test-retest concordance for the PFSDQ-M. The components of the PFSDQ-M and the MRC scale correlated significantly with all of the domains and the total score on the SGRQ (0.49 < r < 0.80; p < 0.01 for all). Conclusions: The Portuguese-language versions of the PFSDQ-M and the MRC scale proved reproducible and valid for use in patients with COPD in Brazil.

Keywords: Pulmonary disease, chronic obstructive; Activities of daily living; Validation studies.

Objective: To establish reproducible electron microscopic criteria for identifying the four major types of neuroendocrine tumors of the lung: carcinoid; atypical carcinoid; large cell neuroendocrine carcinoma; and small cell carcinoma. Methods: Measurements were made on electron micrographs using a digital image analyzer. Sixteen morphometric variables related to tumor cell differentiation were assessed in 27 tumors. The examination under electron microscopy revealed that all of the tumors could be classified as belonging to one of the four categories listed above. Cluster analysis of the morphometry variables was used to group the tumors into three clusters, and Kaplan-Meier survival function curves were employed in order to draw correlations between each cluster and survival. Results: All three clusters of neuroendocrine carcinomas were found to be associated with survival curves, demonstrating the prognostic significance of electron microscopic features. The tumors fell into three well-defined clusters, which represent the spectrum of neuroendocrine differentiation: typical carcinoid (cluster 1); atypical carcinoid and large cell neuroendocrine carcinoma (cluster 2); and small cell carcinoma (cluster 3). Cluster 2 represents an intermediate step in neuroendocrine carcinogenesis, between typical carcinoid tumors and small cell carcinomas. Conclusions: Our findings confirm that electron microscopy is useful in making the diagnosis and prognosis in cases of lung tumor.

Keywords: Neuroendocrine tumors/lung; Microscopy, electron; Cluster analysis; Survival analysis.

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.

Objective: To determine the prevalence of pulmonary hypertension (PH) in patients with cystic fibrosis (CF), to compare clinical characteristics, radiographic scores, pulmonary function, and echocardiographic parameters in patients with and without PH, and to correlate echocardiographic findings with clinical characteristics, radiographic scores, and pulmonary function. Methods: This was a prospective, cross-sectional study involving clinically stable patients (aged 16 or older) enrolled in an adult CF program. The patients were submitted to clinical evaluation, Doppler echocardiography, pulmonary function tests, and chest X-rays. Results: Tricuspid regurgitant jet velocity (TRV) was obtained in 37 of the 40 patients studied. The prevalence of PH was 49% with a TRV cut-off of 2.5 m/s (18 patients) and 30% with a TRV cut-off of 2.8 m/s (11 patients). Peripheral oxygen saturation (SpO2) at rest, clinical score, forced expiratory volume in one second (FEV1), and forced vital capacity (FVC) were significantly lower in the group with PH. The TRV was found to correlate significantly with SpO2 at rest (p < 0.001), clinical score (p < 0.001), radiographic score (p = 0.030), FEV1 in liters (p < 0.001) and in % of predicted (p < 0.001), and FCV in liters (p = 0.008) and in % of predicted (p = 0.001). The single best predictor of TRV was SpO2 at rest (p < 0.001). Conclusion: The high prevalence of PH in the CF patients studied suggests that PH should be considered in the evaluation and follow-up treatment of such patients. The best predictor of PH was SpO2 at rest.

Keywords: Cystic fibrosis; Tricuspid valve/physiopathology; Hypertension, pulmonary; Echocardiography, Doppler.

Objective: To evaluate the impact of thoracic radiotherapy on respiratory function and exercise capacity in patients with breast cancer. Methods: Breast cancer patients in whom thoracic radiotherapy was indicated after surgical treatment and chemotherapy were submitted to HRCT, respiratory evaluation, and exercise capacity evaluation before radiotherapy and at three months after treatment completion. Respiratory muscle strength testing, measurement of chest wall mobility, and complete pulmonary function testing were performed for respiratory evaluation; cardiopulmonary exercise testing was performed to evaluate exercise capacity. The total radiotherapy dose was 50.4 Gy (1.8 Gy/fraction) to the breast or chest wall, including supraclavicular lymph nodes (SCLN) or not. Dose-volume histograms were calculated for each patient with special attention to the ipsilateral lung volume receiving 25 Gy (V25), in absolute and relative values, and mean lung dose. Results: The study comprised 37 patients. After radiotherapy, significant decreases were observed in respiratory muscle strength, chest wall mobility, exercise capacity, and pulmonary function test results (p < 0.05). DLCO was unchanged. HRCT showed changes related to radiotherapy in 87% of the patients, which was more evident in the patients submitted to SCLN irradiation. V25% significantly correlated with radiation pneumonitis. Conclusions: In our sample of patients with breast cancer, thoracic radiotherapy seemed to have caused significant losses in respiratory and exercise capacity, probably due to chest wall restriction; SCLN irradiation represented an additional risk factor for the development of radiation pneumonitis.

Keywords: Breast neoplasms; Radiotherapy; Radiation pneumonitis; Respiratory function tests; Exercise test.