International Labour Organization Classification Research Articles

Occupational health: normative view for the diagnosis of silicosis

Silicosis is an occupational lung fibrosis caused by the inhalation of dust containing free crystalline silica. Its prevalence can vary in different countries and regions. In the case of Chile, silicosis has been recognized as a significant occupational health problem. The clinical presentation of silicosis largely depends on the intensity and duration of exposure. Initially, there may be no signs or symptoms. The differential diagnosis is mainly performed with pulmonary tuberculosis, pulmonary aspergillosis, pulmonary metastasis, sarcoidosis, hypersensitivity pneumonitis, and other pneumoconiosis. After confirming the diagnosis, the process of determining the origin of the pathology begins, for which an Occupational History is required to describe occupational exposure to the risk agent (silica) in terms of time, magnitude, and/or intensity sufficient to develop an occupational-related disease. A Chest X-ray using the ILO (International Labour Organization) technique is necessary, classified as category 1 according to the ILO Classification, and should be interpreted by certified readers. The similarity in radiographic readings necessitates a greater emphasis on the differential diagnosis among these conditions. A high- resolution chest computed tomography without contrast and a lung biopsy should be considered in case of comorbidity, if these diagnostic tests are available. Finally, it is suggested that workers diagnosed with silicosis in the early stages should be identified and removed from silica exposure to prevent disability through medical surveillance.

Long-term follow-up of young denim sandblasters in Turkey.

Denim sandblasting-induced silicosis is a recently identified occupational disease. In this study, we aimed to evaluate pulmonary and radiological changes in the long-term follow-up of former denim sandblasters. Ninety former denim sandblasters were followed from 2007 to 2018. Chest X-rays were evaluated according to the International Labour Organization (ILO) classification. Baseline and final data were compared. Silicosis prevalence, radiological progression and pulmonary dysfunction were evaluated. All of the sandblasters were men. Their mean age was 34 ± 5 years, mean follow-up time was 9 ± 2 years (mean time since initial exposure: 17 ± 2 years) and mean duration of exposure was 34 ± 25 months. Rates of radiological progression and decline in pulmonary during follow-up were 63% and 39%, respectively. During follow-up, all patients were diagnosed with silicosis. All workers who were ILO category 0 at baseline (n = 26, 29%) progressed to higher categories. The number of patients in Category 2 doubled and the number of patients in Category 3 increased by 2.5-fold. Eleven patients developed new large opacities and the number of patients with category C opacity increased from 4 to 13. Exposure time was an independent determinant of radiological progression (OR: 1.0, P = 0.036) and decline in pulmonary function (OR: 1.3, P = 0.019). The prevalence of silicosis in denim sandblasters increases steadily even after exposure is discontinued. Radiological progression was observed in a higher proportion of workers than a decline in lung function. Duration of exposure was the major determinant of disease progression in our study.

Pitfalls of using the ILO classification for silicosis compensation claims.

The International Labour Organization (ILO) Classification of Radiographs of Pneumoconioses is used as the primary tool to determine compensation for pneumoconiosis in Turkey. We aimed to evaluate how the ILO classification applied, but obtaining chest radiographs in the workplace for screening until the completion of compensation claim files by the referral centres, based on the ILO reading. The study included 320 digital chest radiographs previously taken for screening from eight different ceramic factories and having finalised claim files by referral centres. We used an expert reference panel consisting of five ILO readers to re-evaluate all the radiographs independently using ILO standard films and reached a conclusion based on the agreement among at least three readers. The evaluation primarily included technical quality and silicosis diagnosis with an ILO 1/0 or above small profusion. The results were compared with previous findings. Sixty-three (20%) chest radiographs were unacceptable for classification purposes according to the ILO technical quality grades. Among the remaining 257 chest radiographs, we diagnosed 103 with silicosis (40%), while the referral centres diagnosed 182 (71%). A discrepancy was found between our results and previous evaluations. We diagnosed silicosis in 50% and 17% of the previous silicosis and normal evaluations, respectively. Our findings suggest that the use of the ILO classification for compensation claims may be problematic due to the way of its implementation in Turkey in addition to its subjectivity.

Secondary prevention of silicosis and silico-tuberculosis by periodic screening of silica dust exposed workers using serum club cell protein 16 as a proxy marker.

Background and ObjectivesSilicosis is a neglected and widely prevalent occupational disease in India and several other countries such as China, South Africa, Brazil, etc. It is an irreversible, incurable, and progressive disease with high morbidity and mortality, which is mostly caused by occupational exposure to silica dusts. Silicosis is usually detected at an advanced stage, when effective intervention is not possible. But early detection appears to be a cost‐effective way to control it. There is a need for some suitable biomarker, which could detect silicosis at an early stage for further necessary intervention. This study aimed to estimate the lung damage in silicotic subjects and its relationship with serum CC16 as a proxy marker. The ultimate objective was to explore whether CC16 could be used as a screening tool for early detection of silicosis.MethodologyRadiographs of 117 workers having radiological evidences of silicosis were evaluated in accordance with International Labour Organisation (ILO) Classification of chest radiographs and were categorized as mild, moderate, and severe lung damage using a lung damage scoring system, made for the purpose of this study. The concentration of CC16 in serum was determined by enzyme‐linked immunosorbent assay.ResultIt was observed that serum CC16 values were significantly decreased in relation to increasing lung damage. The mean ± standard deviation (SD) serum CC16 value in mild lung damage group was 8.4 ± 0.87 ng/mL as compared to 4.0 ± 2.10 ng/mL in moderate and 0.7 ± 0.21 ng/mL in high lung damage groups. On the other hand, CC16 value of control (healthy) population was found to be 16.3 ± 3.8 ng/mL.ConclusionResult of the study concluded that serum CC16 might be used as a periodic screening tool for early detection of silicosis and for it's secondary prevention. It may be viewed as a new approach toward control of silicosis, and an appropriate policy may be adopted.

Evaluation of lung densitometric and volumetric changes in silicosis patients using three-dimensional software for multidetector CT and the relationship with profusion scores

To evaluate the density and volume changes in the lungs of silicosis patients and their relationship with the disease severity classification of the International Labor Organization (ILO). The multidetector computed tomography (CT) images of 44 patients diagnosed with silicosis and 32 controls that underwent thoracic CT due to trauma were evaluated. Patients with silicosis were divided into three categories according to the ILO classification. Data related to the total lung volume, total lung mean density, lung opacity score, percentage of lung high opacity, and mean density in the lower and upper lobes were obtained using three-dimensional (3D) software. There was no significant difference between the total lung mean densities of the silicosis and control groups (p=0.213); however, a significant difference was observed between the two groups in terms of the total lung volume (p<0.0001). According to the ILO classification, there was a significant difference between the disease severity categories in relation to the percentage of lung high opacity (p=0.000005). A strong correlation was detected between disease severity and high opacity percentage (p<0.0001, r=0.804). According to the ILO classification, there was also a significant difference between disease severity categories in terms of the lung opacity score (p=0.000144), as well as a moderate correlation between disease severity and opacity score (p<0.0001, r=0.580). Total lung volume is a CT finding that shows variation in exposure to crystalline silica. The percentage of high opacity determined using multidetector CT is an effective parameter in evaluating disease severity.

The association of silicosis severity with pectoralis major muscle and subcutaneous fat volumes and the pulmonary artery/aorta ratio evaluated by CT.

Silicosis is an incurable occupational disease that sometimes rapidly progresses with fatal outcomes. We aimed to evaluate the association between disease severity and the change in the pectoralis major muscle volume (PMV), subcutaneous fat volume (SFV), and the pulmonary artery/aorta (P/Ao) ratio in patients with silicosis using computed tomography (CT). The study included 41 male silicosis patients and 41 control group subjects with available chest CT images. Using dedicated software, we measured PMV and SFV from the axial CT images. We calculated the P/Ao ratio and obtained body mass index (BMI) and forced expiratory volume/forced vital capacity (FEV1/FVC) results from hospital records. We used the chest X-ray profusion score according to the International Labor Organization (ILO) classification to evaluate the severity of the silicosis. The mean age was 33.5±4.4 and 34.7±4.7 years in the silicotic and control groups, respectively. The mean BMI, PMV, SFV, and P/Ao values significantly differed between the study and control groups (P = 0.0009, P < 0.0001, P < 0.0001, and P = 0.0029, respectively). According to the ILO classification, there were 12 silicosis patients in category 1, 13 in category 2, and 16 in category 3. A significant difference was found between disease categories in terms of PMV, SFV, P/Ao, BMI, and FEV1/FVC values (P = 0.0425, P = 0.0341, P = 0.0002, P = 0.0492, and P = 0.0004, respectively). Disease severity had a stronger association with decreased PMV and SFV and increased P/Ao ratios than BMI in patients with silicosis caused by denim sandblasting. Thus, CT evaluation might be a useful indicator of disease severity.

Predictors of silicosis and variation in prevalence across mines among employed gold miners in South Africa

BackgroundThe stated intention to eliminate silicosis from the South African goldmining industry as well as current programmes to find and compensate ex-miners with silicosis require an understanding of variation in silicosis prevalence across the industry. We aimed to identify the predictors of radiological silicosis in a large sample of working miners across gold mines in South Africa.MethodsRoutine surveillance chest radiographs were collected from 15 goldmine “clusters” in a baseline survey undertaken in preparation for a separate tuberculosis isoniazid prophylaxis trial. All images were read for silicosis by a health professional experienced in using the International Labour Organisation (ILO) classification. Profusion thresholds of > 1/0 and > 1/1 were used. Demographic and occupational information was obtained by questionnaire. Predictors of silicosis were examined in a multivariable logistic regression model, including age, gender, racial ascription, country of origin, years since starting mine employment, mine shaft, skill category, underground work status and tuberculosis.ResultsThe crude silicosis prevalence at ILO > 1/1 was 3.8% [95% confidence interval (CI) 3.5–4.1%]. The range across mine shafts was 0.8–6.9%. After adjustment for covariates, the interquartile range across shafts was reduced from 2.4 to 1.2%. Black miners [adjusted odds ratio (aOR) 2.8; 95% CI 1.1–7.2] and miners in full-time underground work (aOR 2.1; 95% CI 1.3–3.4) had substantially elevated odds of silicosis, while workers from Mozambique had lower odds (aOR 0.54; 95% CI 0.38–0.77). Silicosis odds rose sharply with both age and years since starting in the industry (p for linear trend < 0.005), with 95.5% of affected miners having > 15 years since first exposure and 2.2% < 10 years.ConclusionsIn surveillance of silicosis in working gold miners time since first exposure remains a powerful predictor. Age appears to be an independent predictor, while the detection of radiological silicosis in short-service miners requires attention. Public risk reporting by mines should include factors bearing on silicosis prevalence, specifically dust concentrations, with independent verification. Studies of silicosis and tuberculosis in ex-miners are needed, supported by an accessible electronic database of the relevant medical and dust exposure records of all gold miners.

Basic Principal for Reading of Chest X Ray Acording to International Labour Organization (ILO) Classification for Pneumoconiosis

Pneumoconiosis is disease that caused by deposition of dust in lung parenchymal with fibrosis was result of it’s reaction. Usually pneumoconiosis diagnose and classified by conventional chest x ray. The International Labour Organization (ILO) described standard system for classified radiograph abnormality of pneumoconiosis based on parenchymal and pleural abnormality. Parenchymal abnormality divided into 2 categories that is small opacities and large opacities. Description steps of chest X ray reading based on ILO classification was technical quality, parenchymal abnormality (shape and size, affected zone and profusion), pleural abnormality (localized, width, extent and severity of calcification) and other abnormality with recorded by symbols (J Respir Indo. 2019; 39: 272-9)

Validity of pulmonary function test measured by spirometry in silicosis patients classified according to international labor organization classification: A retrospective study

Validity of pulmonary function test measured by spirometry in silicosis patients classified according to international labor organization classification: A retrospective study - IJIRM- Print ISSN No: - 2581-4214 Online ISSN No:- 2581-4222 Article DOI No:- 10.18231/2581-4222.2019.0003, IP Indian Journal of Immunology an

Association between increased small airway obstruction and asbestos exposure in patients with asbestosis.

Asbestos exposure may cause asbestos-related lung diseases including asbestosis, pleural abnormalities and malignancies. The role of asbestos exposure in the development of small airway obstruction remains controversial. Anatomic and physiologic small airway abnormalities may develop as part of the pathophysiologic process of asbestosis. We hypothesized that inhalation of asbestos may induce small airway defects in addition to asbestosis and pleural abnormalities. In total, 281 patients with newly diagnosed asbestosis were evaluated. Clinical data were collected from the patients' medical charts. The patients were classified into various stages according to their chest X-ray findings using the International Labour Organization classification. Pulmonary function was evaluated by plethysmography and the forced oscillation technique. Expiratory flow, including the predicted values of the maximum expiratory flow between 25% and 50% of the forced vital capacity (MEF25-50 ), was significantly lower in the different stages of asbestosis. Accordingly, the predicted percentage of R5 -R20 was significantly higher with increasing stages of asbestosis. Furthermore, the duration of exposure to asbestos was significantly associated with the forced expiratory volume in the first second (FEV1 )/forced vital capacity (FVC) ratio and the predicted percentage of MEF25 or MEF50 according to the regression analysis in non-smoking patients with asbestosis. The predicted percentage of FEV1 or the FEV1 /FVC ratio was significantly lower and the predicted percentage of R5 -R20 was significantly higher in smokers than non-smokers. The patients with asbestosis have small airway obstructive defects that are significantly associated with asbestos exposure.

Socio-Demographic and Clinical Characteristics of Turkish Workers with Pneumoconiosis

Pneumoconiosis is caused by inhaling dust. The aim of the study was to analyze 208 cases of workers' pneumoconiosis. Patients' files were used for the descriptive study. All patients were male aged 38.82±13 years. The most important symptom was breathlessness. Patients were denim sandblasters (50.5%), dental technicians (12%), coal miners (6.7%), and others. The mean exposure time before pneumoconiosis occurred was shorter in denim sandblasters and teflon kitchenware producers compared to other occupations (5.4±4.2 and 4.5±3.3 years, respectively). Profusion (76.5%) was more than 1/2 by the International Labour Organization (ILO) classification. Pulmonary function tests were negatively correlated with profusion. Denim sandblasters and teflon kitchenware producers have less exposure time before pneumoconiosis occurs and they become symptomatic earlier. As Turkish workers suffering from pneumoconiosis are younger, measures to prevent pneumoconiosis must be the priority of the healthcare authorities.

Lung Pathology in U.S. Coal Workers with Rapidly Progressive Pneumoconiosis Implicates Silica and Silicates.

Recent reports of progressive massive fibrosis and rapidly progressive pneumoconiosis in U.S. coal miners have raised concerns about excessive exposures to coal mine dust, despite reports of declining dust levels. To evaluate the histologic abnormalities and retained dust particles in available coal miner lung pathology specimens, and to compare these findings with those derived from corresponding chest radiographs. Miners with severe disease and available lung tissue were identified through investigator outreach. Demographic as well as smoking and work history information was obtained. Chest radiographs were interpreted according to the International Labor Organization classification scheme to determine if criteria for rapidly progressive pneumoconiosis were confirmed. Pathology slides were scored by three expert pulmonary pathologists using a standardized nomenclature and scoring system. Thirteen cases were reviewed, many of which had features of accelerated silicosis and mixed dust lesions. Twelve had progressive massive fibrosis, and 11 had silicosis. Only four had classic lesions of simple coal workers' pneumoconiosis. Four had diffuse interstitial fibrosis with chronic inflammation, and two had focal alveolar proteinosis. Polarized light microscopy revealed large amounts of birefringent mineral dust particles consistent with silica and silicates; carbonaceous coal dust was less prominent. On the basis of chest imaging studies, specimens with features of silicosis were significantly associated (P = 0.047) with rounded (type p, q, or r) opacities, whereas grade 3 interstitial fibrosis was associated (P = 0.02) with the presence of irregular (type s, t, or u) opacities. Our findings suggest that rapidly progressive pneumoconiosis in these miners was associated with exposure to coal mine dust containing high concentrations of respirable silica and silicates.

Silicosis Appears Inevitable Among Former Denim Sandblasters: A 4-Year Follow-up Study

The course of denim sandblasting silicosis is unknown. We aimed to reevaluate former sandblasters studied in 2007 for incident silicosis, radiographic progression, pulmonary function loss, and mortality and to examine any associations between these outcomes and previously demonstrated risk factors for silicosis. We defined silicosis on chest radiograph as category 1/0 small opacity profusion using the International Labor Organization classification. We defined radiographic progression as a profusion increase of two or more subcategories, development of a new large opacity, or an increase in large opacity category. We defined pulmonary function loss as a ≥ 12% decrease in FVC. Among the 145 former sandblasters studied in 2007, 83 were reassessed in 2011. In the 4-year follow-up period, nine (6.2%) had died at a mean age of 24 years. Of the 74 living sandblasters available for reexamination, the prevalence of silicosis increased from 55.4% to 95.9%. Radiographic progression, observed in 82%, was associated with younger age, never smoking, foreman work, and sleeping at the workplace. Pulmonary function loss, seen in 66%, was positively associated with never smoking and higher initial FVC % predicted. Death was associated with never smoking, foreman work, number of different denim-sandblasting places of work, sleeping at the workplace, and lower pulmonary function, of which only the number of different places worked remained in multivariate analyses. This 4-year follow-up suggests that almost all former denim sandblasters may develop silicosis, despite short exposures and latency.

Update: standardized CT/HRCT classification of occupational and environmental thoracic diseases in Germany

The high-resolution computed tomography (HRCT) coding scheme of the international classification of occupational and environmental respiratory diseases (ICOERD) presented here is an instrument for a standardized semiquantitative description of occupation and environment-linked as well as other pulmonary and pleural diseases. Analogous to the International Labour Organization (ILO) classification, the ICOERD coding scheme should always be used when the CT/HRCT examination is employed for occupational medical investigations or expert opinions. After publication of the guidelines and recommendations on diagnostics and expert assessment of asbestos-linked diseases and silicosis, the application of a standardized investigation program and assessment with the ICOERD classification form are obligatory, at least for the initial assessment. Furthermore, its use in the field of follow-up assessments of occupational diseases should be encouraged in order to guarantee comparability between individual reports (interreader variability) and at least a semiquantitative assessment of disease progression in isolated cases. Because the anatomical structures in projection radiography and CT are not presented identically, a 1:1 transfer of the results of the ILO classification to the CT/HRCT coding scheme is not possible. An overview image of the thorax does not allow overlap-free reproduction of structures, in contrast to CT. These methodological differences can in cases of isolated assessment result in different opinions of projection and CT images mostly by different investigators. In cases of discrepant opinions an integrated report of findings by combination of all information from both procedures is necessary.

The “dirty chest”—correlations between chest radiography, multislice CT and tobacco burden

Cigarette smoking-induced airway disease commonly results in an overall increase of non-specific lung markings on chest radiography. This has been described as "dirty chest". As the morphological substrate of this condition is similar to the anthracosilicosis of coal workers, we hypothesised that it is possible to quantify the radiological changes using the International Labour Organization (ILO) classification of pneumoconiosis. The aims of this study were to evaluate whether there is a correlation between the extent of cigarette smoking and increased lung markings on chest radiography and to correlate the chest radiographic scores with findings on CT studies. In a prospective analysis a cohort of 85 smokers was examined. The cigarette consumption was evaluated in pack years (defined as 20 cigarettes per day over 1 year). Film reading was performed by two board-certified radiologists. Chest radiographs were evaluated for the presence of thickening of bronchial walls, the presence of linear or nodular opacities, and emphysema. To correlate the smoking habits with the increase of overall lung markings in chest radiography, the ILO profusion score was converted to numbers ranging from zero to nine. Chest radiographs were rated according to the complete set of standard films of the revised ILO classification. 63/85 (74%) of the smokers showed an increase in overall lung markings on chest radiography; 32 (37%) had an ILO profusion score of <1/1, 29 (34%) had an ILO profusion score of <2/2 and 2 (2%) had an ILO score of ≥ 2/2. There was a significant positive linear correlation between the increase of overall lung markings on chest radiography and the cigarette consumption quantified as pack years (r=0.68). The majority of the heavy smokers (>40 pack years) showed emphysema; there was no significant difference between the prevalence of emphysema as diagnosed by CT (62%) or chest radiography (71%) (p<0.05).The most common findings in CT were thickening of bronchial walls (64%) and the presence of emphysema (62%) and of intralobular opacities (61%). Ground-glass opacities were seen in only 7% of our patients. Bronchial wall thickening and intralobular opacities as seen in CT showed a positive linear correlation with the increase of overall lung markings on chest radiography.

Do Labor Statistics Depend on How and to Whom the Questions Are Asked? Results from a Survey Experiment in Tanzania

Labor market statistics are critical for assessing and understanding economic development. However, widespread variation exists in how labor statistics are collected in household surveys. This paper analyzes the effects of alternative survey design on employment statistics by implementing a randomized survey experiment in Tanzania. Two features of the survey design are assessed - the level of detail of the employment questions and the type of respondent. It turns out that both features have relevant and statistically significant effects on employment statistics. Using a short labor module without screening questions induces many individuals to adopt a broad definition of employment, incorrectly including domestic duties. But after reclassifying those in domestic work as 'not working' in order to obtain the correct International Labor Organization (ILO) classification, the short module turns out to generate lower female employment rates, higher working hours for both men and women who are employed, and lower rates of wage employment than the detailed module. Response by proxy rather than self-report has no effect on female labor statistics but yields substantially lower male employment rates, mostly due to underreporting of agricultural activity. The large impacts of proxy responses on male employment rates are attenuated when proxy informants are spouses and individuals with some schooling.

Levels of Exhaled Breath Condensate pH and Fractional Exhaled Nitric Oxide in Retired Coal Miners.

Inhaled inorganic dusts, such as coal, can cause inflammation and fibrosis in the lungs, known as pneumoconiosis. Diagnosis of pneumoconiosis depends on morphological changes by radiological findings and functional change by pulmonary function test (PFT) . Unfortunately, current diagnostic findings are limited only to lung fibrosis, which is usually irreversibly progressive. Therefore, it is important that research on potential and prospective biomarkers for pneumoconiosis should be conducted prior to initiation of irreversible radiological or functional changes in the lungs. Analytical techniques using exhaled breath condensate (EBC) or exhaled gas are non-invasive methods for detection of various respiratory diseases. The objective of this study is to investigate the relationship between inflammatory biomarkers, such as EBC pH or fractional exhaled nitric oxide (FENO) , and pneumoconiosis among 120 retired coal miners (41 controls and 79 pneumoconiosis patients) . Levels of EBC pH and FENO did not show a statistically significant difference between the pneumoconiosis patient group and pneumoconiosis patients with small opacity classified by International Labor Organization (ILO) classification. The mean concentration of FENO in the low percentage FEV1 (< 80%) was lower than that in the high percentage (80% ≤) (p = 0.023) . The mean concentration of FENO in current smokers was lower than that in non smokers (never or past smokers) (p = 0.027) . Although there was no statistical significance, the levels of FENO in smokers tended to decrease, compared with non smokers, regardless of pneumoconiosis. In conclusion, there was no significant relationship between the level of EBC pH or FENO and radiological findings or PFT. The effects between exhaled biomarkers and pneumoconiosis progression, such as decreasing PFT and exacerbation of radiological findings, should be monitored.

Diagnosis of Severe Silicosis in Young Adults Working in Stone Polishing and Mining in Minas Gerais, Brazil

This study describes the occurrence of silicosis in a group of stone polishing and/or mining workers who began working under the age of 18, the minimum age in Brazil for working in hazardous or unhealthy conditions. The design is that of a case series with medical follow up via a surveillance program that included medical and occupational histories, chest radiography interpreted according to International Labour Organization (ILO) Classification, and spirometry. The findings call attention to the importance of the problem of silicosis, which persists in the region despite new production technologies, legal requirements, and initiatives to protect workers. Silicosis is a public health problem that must be addressed by the implementation of public policies to improve working conditions and ensure children and teenagers are kept away from hazardous work. While Brazil has started to be a part of the global effort to eliminate silicosis and the worst forms of child labor, there are still problems that must be addressed.

BMI distribution/social stratification in Swiss conscripts from 1875 to present

We aimed to extend the actual overweight discussion with new unbiased Swiss conscript data from 2005 to 2006, and to present for the first time Swiss data on body mass index (BMI) before 1950 and for the late-nineteenth century. For this study, 19-year-old Swiss male conscripts (draft army; Cantons Bern, Zurich, Basel-Stadt and Basel-Land) from the census of 1875-1879, 1933-1939 and 2005-2006 (N=28 033; 2005-2006 census) were included. BMI distribution (World Health Organization (WHO) classification) and social stratification (International Labour Organization classification) were main outcome measures. Mean BMI of 19-year-old men in Switzerland increased in the 50 years between the 1870s and the 1930s by 0.80 kg/m(2) and between the 1930s and 2005 by 1.45 kg/m(2). The modern BMI sample is much more right skewed and s.d. is higher. Obesity prevalence (according to modern WHO classification) has increased by a factor of 105 from 1870s until present. Over 23% of our representative sample of Swiss men in 2005-2006 had a BMI of over 25 kg/m(2). In 2005-2006, contrary to the nineteenth century, unskilled workers had articulately higher BMI values at the 75th, 90th and 95th percentile than students; 12% of unskilled workers were obese against 2% of students. It thus seems that BMI relations between the upper and the lower end of the socio-economic strata changed inversely from the late-nineteenth century to 2005-2006. We further propose that the phenomenon of massive right-skewing BMI distribution between the 1930s and 2005-2006 affected the lower socio-economic strata to a far greater extent than the higher socio-economic group.

Particularités de la tuberculose pulmonaire chez le tabagique

Tobacco smoking and tuberculosis (TB) are two major public health problems, and the former may affect the morbidity and mortality rates for the latter. This study sought to compare the clinical and radiologic aspects of pulmonary TB, as well as outcome, in smokers and nonsmokers. This retrospective case control study examined the files of 90 patients in our pulmonary department with active pulmonary TB, 45 of them smokers and 45, nonsmokers. To analyze the seriousness of the radiologic lesions, we used a score based on the International Labour Organization classification for simple pneumoconiosis, rating lesions in 4 grades according to severity and extent. The mean age of the patients, all men, was 29 years (range: 16-50 years). Symptoms were similar in both groups, with no significant clinical or bacteriological differences between the two groups. However, the highest severity score was found in 81% of the smoking group compared with 15% of the nonsmokers (p<0.001). Moreover, after patients were cured, only smokers had severe radiological sequelae (13.8% versus 0%, p<0.05). Our study is one of the few to compare the radiological appearance of TB in smoking and nonsmoking patients. Smoking is associated with much more extensive and severe radiological TB lesions and sequelae and increases the risk of morbidity and mortality in TB patients. Therefore smoking prevention and cessation should be a priority in TB prevention programs.