Surveillance for occupational respiratory diseases in developing countries.

The burden of chronic diseases, including occupational respiratory diseases (ORDs), is increasing worldwide. Nevertheless, epidemiological data on these conditions are scarce in most countries. Therefore, it is important to conduct surveillance to monitor ORDs, particularly in developing countries, where the working population is especially vulnerable and the health system infrastructure is usually weak. This article provides a general framework for the implementation of ORD surveillance in developing countries. The main objectives of surveillance are to describe incidence and prevalence of ORDs, as well as to identify sentinel events and new associations between occupational exposures and health outcomes. Diseases with high morbidity and mortality and those in which early diagnosis with standardized tests are available are especially suitable for surveillance activities. Simple strategies, preferably using existing resources and technology, are the best option for surveillance in developing countries. This article offers examples of specific surveillance systems that are in place in Brazil, China, Cuba, India, and South Africa.

Mesothelioma incidence in 50 states and the District of Columbia, United States, 2003-2008.

BACKGROUND: The decline in asbestos use in the United States may impact mesothelioma incidence. OBJECTIVE: This report provides national and state-specific estimates of mesothelioma incidence in the United States using cancer surveillance data for the entire US population. METHODS: Data from the National Program for Cancer Registries and the Surveillance, Epidemiology, and End Results program were used to calculate incidence rates and annual percent change. RESULTS: During 2003-2008, an average of 1.05 mesothelioma cases per 100 000 persons were diagnosed annually in the United States; the number of cases diagnosed each year remained level, whereas rates decreased among men and were stable among women. CONCLUSION: US population-based cancer registry data can be used to determine the burden of mesothelioma and track its decline. Even 30 years after peak asbestos use in the United States, 3200 mesothelioma cases are diagnosed annually, showing that the US population is still at risk.

Comparison of digital with film radiographs for the classification of pneumoconiotic pleural abnormalities.

RATIONALE AND OBJECTIVES: Analog film radiographs are typically used to classify pneumoconiosis to allow comparison with standard film radiographs. The aim of this study was to determine if digital radiography is comparable to film for the purpose of classifying pneumoconiotic pleural abnormalities. MATERIALS AND METHODS: Subjects were 200 asbestos-exposed patients, from whom digital and film chest radiographs were obtained along with chest high-resolution computed tomographic scans. Using a crossover design, radiographs were independently read on two occasions by seven readers, using conventional International Labour Organization standards for film and digitized standards for digital. High-resolution computed tomographic scans were read independently by three readers. Areas under the receiver-operating characteristic curves were calculated using high-resolution computed tomographic ratings as the gold standard for disease status. Mixed linear models were fit to estimate the effects of order of presentation, occasion, and modality, treating the seven readers as a random effect. Comparing digital and film radiography for each reader and occasion, crude agreement and agreement beyond chance (κ) were also calculated. RESULTS: The linear models showed no statistically significant sequence effect for order of presentation (P = .73) or occasion (P = .28). Most important, the difference between modalities was not statistically significant (digital vs film, P = .54). The mean area under the curve for film was 0.736 and increased slightly to 0.741 for digital. Mean crude agreement for the presence of pleural abnormalities consistent with pneumoconiosis across all readers and occasions was 78.3%, while the mean κ value was 0.49. CONCLUSIONS: These results indicate that digital radiography is not statistically different from analog film for the purpose of classifying pneumoconiotic pleural abnormalities, when appropriate standards are used.

Occupational risks for idiopathic pulmonary fibrosis mortality in the United States.

Metal and wood dust exposures have been identified as possible occupational risk factors for idiopathic pulmonary fibrosis (IPF). We analyzed mortality data using ICD-10 code J84.1--"Other interstitial pulmonary diseases with fibrosis," derived age-adjusted mortality rates for 1999-2003, and assessed occupational risks for 1999, by calculating proportionate mortality ratios (PMRs) and mortality odds ratios (MORs) using a matched case-control approach. We identified 84,010 IPF deaths, with an age-adjusted mortality rate of 75.7 deaths/million. Mortality rates were highest among males, whites, and those aged 85 and older. Three industry categories with potential occupational exposures recognized as risk factors for IPF were identified: "Wood buildings and mobile homes" (PMR = 4.5, 95% confidence interval (CI) 1.2-11.6 and MOR = 5.3, 95% CI 1.2-23.8), "Metal mining" (PMR = 2.4, 95% CI 1.3-4.0 and MOR = 2.2, 95% CI 1.1-4.4), and "Fabricated structural metal products" (PMR = 1.9, 95% CI 1.1-3.1 and MOR = 1.7, 95% CI 1.0-3.1). Workers in these industry categories may benefit from toxicological studies and improved surveillance for this disease.

Rayon flock: a new cause of respiratory morbidity in a card processing plant.

BACKGROUND: Following employee respiratory concerns, we investigated the health effects of rayon flock exposure at a card manufacturing plant. METHODS: We conducted a cross-sectional survey including environmental evaluation, standardized questionnaires, spirometry, carbon monoxide diffusing capacity testing, and methacholine challenge testing. RESULTS: From a total of 239 participants, 146 (61%) reported working at least 1 hr per week in areas where flock-coated cards are processed (flock workers) and 47 (20%) reported cleaning equipment with compressed air. These workers had generally higher prevalences of respiratory symptoms. Flock workers and employees with longer tenure at areas where flock-coated cards are processed were more likely to have restrictive impairment of lung function. Although dust and fiber samples were largely below the detection limits, peak exposures to airborne particulate occurred during cleaning with compressed air. CONCLUSIONS: Working with rayon flock and cleaning with compressed air were associated with health effects in workers at this plant.

Twenty-three years of hypersensitivity pneumonitis mortality surveillance in the United States.

BACKGROUND: There are few population-based studies addressing hypersensitivity pneumonitis (HP) in the United States. The National Institute for Occupational Safety and Health (NIOSH) has nationally comprehensive longitudinal mortality data that can contribute to a better understanding of the epidemiology of HP. METHODS: The National Center for Health Statistics multiple cause-of-death data were analyzed for the period 1980-2002. Annual death rate was age-adjusted to the 2000 U.S. standard population. Death rate time-trends were calculated using a linear regression model and geographic distribution of death rates were mapped by state and county. Proportionate mortality ratios (PMRs) by usual industry and occupation adjusted for age, sex, and race, were based on data from 26 states reporting industry and occupation during 1985-1999. RESULTS: Overall age-adjusted death rates increased significantly (P < 0.0001) between 1980 and 2002, from 0.09 to 0.29 per million. Wisconsin had the highest rate at 1.04 per million. Among industries, PMR for HP was significantly high for agricultural production, livestock (PMR, 19.3; 95% CI, 14.0-25.9) and agricultural production, crops (PMR, 4.3; 95% CI, 3.0-6.0). Among occupations, PMR for HP was significantly elevated for farmers, except horticulture (PMR, 8.1; 95% CI, 6.4-10.2). CONCLUSIONS: These findings indicate that agricultural industries are closely associated with HP mortality and preventive strategies are needed to protect workers in these industries.

Marcadores morfológicos de prognóstico no mesotelioma maligno: um estudo de 58 casos / Morphological aspects as prognostic factors in malignant mesothelioma: a study of 58 cases

OBJETIVO: Diversos marcadores têm se mostrados promissórios como preditores do diagnóstico e prognóstico do mesotelioma maligno (MM). MÉTODO: Mediante estudo morfométrico e inmunomarcação de componentes estromais (calretinina, CEA, Leu-M1 e trombomodulina) e nucleares (p53 e Ki-67), avaliamos a sobrevida após o diagnóstico de 58 pacientes com tumores malignos de pleura. RESULTADOS: O padrão histológico típico do mesotelioma maligno foi encontrado em 50 casos e o padrão atípico em 8 casos. Imunohistoquimicamente foram confirmados 40 casos como sendo mesoteliomas, 11 como adenocarcimonas e 7 casos do padrão atípico não puderam ser classificados. A análise multivariavel do Cox demonstrou a coexistência de um maior fator de risco de morte (476.2), nos pacientes com idade avançada, subtipo histológico bifásico e componentes de expressão nuclear. CONCLUSÃO: A calretinina foi o marcador inmunohistoquímico (IHQ) mais útil para o diagnóstico do mesotelioma e o CEA para o de adenocarcinoma. A quantificação por IHQ da trombomodulina foi fundamental na diferenciação do mesotelioma quando este foi positivo tanto para calretinina e como para o CEA. A informação prognostica mais valiosa foi a fornecida pela análise rotineira histopatológica do tipo histológico tumoral. Um ponto importante, divisor natural, foi a idade com uma media de 55 anos e 30.5 por cento de componentes nucleares de marcação IHQ, separando os pacientes em dois grupos: pacientes com uma sobrevivência curta contra pacientes com uma sobrevivência mais longa que a esperada. Assim, a análise histopatológica oferece uma arma poderosa e de elevado potencial para guiar no tratamento adjuvante de quimioterápicos após a retirada cirúrgica do mesotelioma.

OBJECTIVE: Various markers have shown promise as diagnostic markers and prognostic predictors in malignant mesothelioma (MM). METHODS: Through morphometric and immunological studies of markers in stromal components (calretinin, CEA, Leu-M1 and thrombomodulin) and nuclear components (p53 and Ki-67), we evaluated post-diagnosis survival in 58 patients with MM. RESULTS: The histologic pattern of the MM was typical in 50 cases and atypical in 8. Through immunohistochemistry, we confirmed 40 cases of mesothelioma and 11 cases of adenocarcinoma, although we were unable to classify 7 of the 8 cases presenting atypical histologic patterns. Cox multivariate analysis revealed that the risk factor for death was higher (476.2) among patients of advanced age, presenting the biphasic subtype and testing positive for components expressed at the nuclear level. CONCLUSION: The most useful immunohistochemical markers were was calretinin (for mesothelioma) and CEA (for adenocarcinoma). Immunohistochemical quantification of thrombomodulin facilitated the diagnosis of mesothelioma in patients testing positive for both calretinin and CEA. The most useful prognostic information was that provided by the routine histopathological analysis of the tumor type. It is of note that the combination of a mean age of 55 years and 30.5 percent immunohistochemical markers in nuclear components created a natural dividing point between patients in which survival was shorter than expected and those in which it was longer than expected. Therefore, histopathological analysis offers a powerful weapon with great potential to inform decisions regarding the use of adjuvant chemotherapy after surgical excision of a mesothelioma.

Vigilância epidemiológica e doenças ocupacionais respiratórias / Epidemiological surveillance and occupational respiratory diseases

A consolidação de uma base de dados é fundamental para a priorização de medidas de orientação, prevenção e controle das doenças em geral e para a elaboração de políticas públicas em saúde. Enquanto vários países possuem consistentes sistemas de vigilância epidemiológica, entre nós, ainda carecemos de uma estrutura adequada de coleta, processamento e divulgação de dados. Entendemos como imprescindível uma ação conjunta entre os profissionais da saúde afeitos ao tema para que, o mais breve possível, possamos construir uma base de dados que contemple satisfatoriamente a epidemiologia das doenças respiratórias ocupacionais.

For every communicable disease, the construction of a database is fundamental to prioritizing related measures (educational, prevention and control), as well as to the development of public health policies. Although various countries possess reliable systems of epidemiological surveillance, Brazil still lacks an adequate structure for the collection, processing and dissemination of data. We consider it imperative that the health professionals working in this area make a unified effort, as soon as possible, to compile a database that suitably addresses the epidemiology of occupational respiratory diseases.

Malignant mesothelioma mortality in the United States, 1999-2001.

Malignant mesothelioma is strongly associated with asbestos exposure. This paper describes demographic, geographic, and occupational distributions of mesothelioma mortality in the United States, 1999-2001. The data (n = 7,524) were obtained from the National Center for Health Statistics multiple-cause-of-death records. Mortality rates (per million per year) were age-adjusted to the 2000 U.S. standard population, and proportionate mortality ratios (PMRs) were calculated by occupation and industry, and adjusted for age, sex, and race. The overall age-adjusted mortality rate was 11.52, with males (22.34) showing a sixfold higher rate than females (3.94). Geographic distribution of mesothelioma mortality is predominantly coastal. Occupations with significantly elevated PMRs included plumbers/pipefitters and mechanical engineers. Industries with significantly elevated PMRs included ship and boat building and repairing, and industrial and miscellaneous chemicals. These surveillance findings can be useful in generating hypotheses and developing strategies to prevent mesothelioma.

Morphological aspects as prognostic factors in malignant mesothelioma: a study of 58 cases.

OBJECTIVE: Various markers have shown promise as diagnostic markers and prognostic predictors in malignant mesothelioma (MM). METHODS: Through morphometric and immunological studies of markers in stromal components (calretinin, CEA, Leu-M1 and thrombomodulin) and nuclear components (p53 and Ki-67), we evaluated post-diagnosis survival in 58 patients with MM. RESULTS: The histologic pattern of the MM was typical in 50 cases and atypical in 8. Through immunohistochemistry, we confirmed 40 cases of mesothelioma and 11 cases of adenocarcinoma, although we were unable to classify 7 of the 8 cases presenting atypical histologic patterns. Cox multivariate analysis revealed that the risk factor for death was higher (476.2) among patients of advanced age, presenting the biphasic subtype and testing positive for components expressed at the nuclear level. CONCLUSION: The most useful immunohistochemical markers were was calretinin (for mesothelioma) and CEA (for adenocarcinoma). Immunohistochemical quantification of thrombomodulin facilitated the diagnosis of mesothelioma in patients testing positive for both calretinin and CEA. The most useful prognostic information was that provided by the routine histopathological analysis of the tumor type. It is of note that the combination of a mean age of 55 years and 30.5% immunohistochemical markers in nuclear components created a natural dividing point between patients in which survival was shorter than expected and those in which it was longer than expected. Therefore, histopathological analysis offers a powerful weapon with great potential to inform decisions regarding the use of adjuvant chemotherapy after surgical excision of a mesothelioma.

[Epidemiological surveillance and occupational respiratory diseases]. / Vigilância epidemiológica e doenças ocupacionais respiratórias.

For every communicable disease, the construction of a database is fundamental to prioritizing related measures (educational, prevention and control), as well as to the development of public health policies. Although various countries possess reliable systems of epidemiological surveillance, Brazil still lacks an adequate structure for the collection, processing and dissemination of data. We consider it imperative that the health professionals working in this area make a unified effort, as soon as possible, to compile a database that suitably addresses the epidemiology of occupational respiratory diseases.

High-resolution CT in silicosis: correlation with radiographic findings and functional impairment.

OBJECTIVE: To assess high-resolution computed tomography (HRCT) findings in silicosis and to better define the role of HRCT in early detection of parenchymal abnormalities in silica-exposed workers. METHODS: Forty-one stone carvers were evaluated with chest radiographs (CR), HRCT, and pulmonary function tests (PFT). Inter-reader agreement was calculated using the kappa statistic (k). Correlation between radiographic and HRCT profusion scores and PFT was assessed using the Spearman correlation coefficient. RESULTS: The most common HRCT findings were branching centrilobular structures, seen in 28/41 workers (68.3%). Nodules consistent with silicosis were detected in 53.7% workers on CR and in 56.1% workers on HRCT. Inter-reader agreement for diagnosis of silicosis was better on HRCT (k = 0.84) than on CR (k = 0.54). Small opacity profusion on HRCT correlated inversely with total lung capacity and FVC%. CONCLUSION: Profusion of opacities on HRCT correlates with functional impairment. The presence of branching centrilobular structures may be helpful in early recognition of silicosis.

Tracheobronchopathia osteochondroplastica in a patient with silicosis: CT, bronchoscopy, and pathology findings.

A case of tracheobronchopathia osteochondroplastica in a patient with silicosis is reported, showing a rare association of disease. Etiological hypotheses and clinical aspects are discussed. Radiologic, bronchoscopic, and pathologic findings are demonstrated with emphasis on the role of computed tomography (CT) in the diagnosis of this disease.

Malignant mesothelioma surveillance: a comparison of ICD 10 mortality data with SEER incidence data in nine areas of the United States.

With the implementation in 1999 of ICD-10 death certificate coding in the United States, mortality data specific to malignant mesothelioma became readily available on a national basis. To evaluate the accuracy and completeness of diagnosis and coding for mesothelioma on the death certificate, mortality information was compared with incidence data. A mortality/incidence ratio was calculated for each of the nine areas covered by the SEER Program, using National Vital Statistics mortality data from 1999 and 2000, and the SEER incidence data for 1998 and 1999. The mortality/incidence ratio for the two years combined for all areas was 0.82. Only two areas (Connecticut and Atlanta) had ratios <80%. The overall correlation coefficient between mortality and incidence rates was 0.96. Thus, mortality data coded using ICD-10 can be a valid source for mesothelioma surveillance and can be instituted without major cost if a national mortality statistics program based on ICD-10 is in place, making it feasible even for developing countries.

High prevalence of silicosis among stone carvers in Brazil.

BACKGROUND: In the city of Petrópolis, Brazil, artisans carve souvenirs from a variety of silica-containing minerals. The finding of pulmonary massive fibrosis in one of the workers motivated an investigation of the prevalence of silicosis in this group. METHODS: Between January 2000 and June 2002, a cross-sectional study was performed. We obtained clinical and occupational histories, spirometry, lung volumes, and carbon monoxide diffusion capacity measurements. Chest radiographs and high-resolution computed tomographies (HRCT) were evaluated. Personal air samples were analyzed. RESULTS: Forty-two stone carvers were examined. The prevalence of silicosis was 53.7%. HRCT better characterized silicotic lesions compared to chest radiographs. Early coalescence of small opacities was associated with lung function impairment. The concentration of dust exceeded permissible limits in 91% of the workplaces. CONCLUSIONS: Exposure to high levels of silica dust was associated with an increased prevalence of silicosis among stone carvers. Am. J. Ind. Med. 45:194-201, 2004.

Mortality from pleural mesothelioma in Rio de Janeiro, Brazil, 1979-2000: estimation from death certificates, hospital records, and histopathologic assessments.

To obtain information about the occurrence of pleural mesothelioma on a population basis in Brazil, mortality related to pleural tumors in the State of Rio de Janeiro during 1979-2000 was examined. Death certificates with pleural tumors as the main cause of death and hospital records were analyzed, together with histopathologic material, which was reevaluated. Of 217 death certificates coded as pleural tumors, 34.1% were considered wrongly coded. Results after reclassification were: definite mesothelioma = 45 cases; probable = 7; possible = 31; inconclusive = 65; other tumors = 11. Thus, the number of mesotheliomas in Rio de Janeiro in 1979-2000 is estimated to have been 83. The analysis also suggests a problem with mortality codification in the State.