[Diffuse interstitial lung disease of possible occupational origin treated at the Navarra Health Service. Navarra, Spain, 2017-2022]. / Enfermedad pulmonar intersticial difusa de posible origen laboral atendida en el Servicio Navarro de Salud. Navarra, España, 2017-2022.

INTRODUCTION: Diffuse interstitial lung disease (ILD) describes a broad group of pulmonary inflammatory and fibrosis disorders. Asbestosis and silicosis are the main causes linked to occupational exposure. The aim of this study was to estimate the proportion of cases with possible occupational origin and describe their exposure, clinical, and occupational status. METHOD: We conducted a retrospective longitudinal study of ILD cases between 2017 - 2022 at the University Hospital of Navarra was conducted. Information was supplemented with interviews of cases with possible occupational origin. The occupational proportion was calculated, labor and clinical characteristics analyzed, by statistical comparison of percentages and means. RESULTS: Out of 1067 ILD cases, 56 had a possible occupational origin 5,2% (95% CI 3,9-6,6%). 36 (64,3%) corresponded to asbestosis, 15 (26,8%) to silicosis, and 5 (8,9%) to unspecified pneumoconiosis. The most frequent activities in silicosis were "stone cutting-carving" and in asbestosis "manufacture of iron products". The average age of asbestosis cases was higher than that of silicosis cases (78,2 vs. 67,3 years), as well as their clinical manifestation. Five cases (8,9%) had been recognized as occupational diseases. CONCLUSIONS: The implementation of a computer tool in medical records has made it possible to estimate the magnitude and assess the evolution of occupational ILD treated in the Public Health Service. Economic activities reflect the economic risk structure of the region. However, there is a lack of recognition of these diseases as occupational illnesses and they represent a preventable burden of respiratory disease.

Introducción: La enfermedad pulmonar intersticial difusa (EPID) describe un amplio grupo de trastornos con inflamación y fibrosis pulmonar. La asbestosis y la silicosis son las principales causas por exposición laboral. El objetivo de este trabajo fue estimar la proporción de casos de posible origen laboral y describir la exposición, situación clínica y laboral.  Método: Estudio longitudinal retrospectivo de los casos de EPID, en el período 2017-2022 en el Hospital Universitario de Navarra. Se completó la información con entrevista a los casos de posible origen laboral.  Resultados: De un total de 1067 casos de EPID, 56 tuvieron un posible origen laboral, 5,2% (3,9-6,6 IC 95%) 36 (64,3%) correspondieron a asbestosis, 15 (26,8%) a silicosis y 5 (8,9%) a neumoconiosis no especificada. Las actividades más frecuentes en silicosis fueron "corte-tallado de piedra" y para asbestosis "fabricación productos hierro". La media de edad de los casos de asbestosis fue superior a los de silicosis (78,2 vs. 67,3 años), así como su afectación clínica. Cinco casos (8,9%) habían sido reconocidos como enfermedad profesional  Conclusiones: La implementación de una herramienta informática en historia clínica ha hecho posible estimar la magnitud y valorar la evolución de las EPID laborales atendidas en el servicio nacional de salud. Las actividades económicas reflejan la estructura económica de riesgo de la región. Sin embargo, existe una falta de su reconocimiento como enfermedad profesional y suponen una carga de enfermedad respiratoria evitable.

[Medical expert reports in chest disease; the question of imputability of death]. / Expertise médicale en pneumologie; question de l'imputabilité du décès.

In the course of an investigation, judicial or not, the expert opinion encompasses several questions of a different nature, including the following one « did the patient die of a disease he/she was supposed to suffer from at time of death? ¼ Based on a personal experience over one year in 2008, the goal of this paper is to tackle this question of imputability, which was asked in respect of 12 investigations, including ten of occupational diseases, one of nosocomial infection and one iatrogenic accident. Only two autopsies were carried out; one autopsy refusal was reported. In five out of 12 cases, the imputability of death related to an occupational disease or an iatrogenic accident was considered by the expert to be certain in one case, very probable in two cases, and possible in two cases; in seven out to 12 cases, imputability of death was unlikely, since the cause of death was unknown in two cases, or was not the suggested cause in five cases. The discussion considers several arguments that can help answer this question: evaluation of the vital prognosis of the disease, the importance of the quality of medical records, the contributions and limits of autopsy findings, deaths that result from multiple causes, and the concept of aggravating circumstances.

Retrospective mortality cohort study of Italian workers compensated for silicosis.

OBJECTIVES: To estimate cause specific mortality in a large cohort of Italian workers compensated for silicosis. METHODS: The cohort included 14 929 subjects (14,098 men and 831 women) compensated for silicosis between 1946 and 1979, alive on 1 January 1980, and resident in Tuscany (a region of central Italy with 3,547,000 inhabitants). Mortality follow up ranged from 1980 to 1999. Vital status and the causes of death were determined by linkage with the regional mortality registry and with the national mortality database. The cohort mortality rates were compared to the rates of the local reference population. SMRs and their 95% confidence intervals were computed assuming a Poisson distribution of the observed deaths. Specific SMR analyses were performed according to the level of disability, the year of compensation assignment, and the job type. RESULTS: A significant excess mortality was observed in male silicotics for cancer of the lung, trachea, and bronchus and cancer of the liver, respiratory diseases (silicosis, asbestosis, antracosilicosis, and other pneumoconiosis), and for tubercolosis. Statistically significant mortality excess was observed in female silicotics for respiratory diseases (specifically silicosis and other pneumoconiosis) and tuberculosis. Analyses for period of compensation assignment showed a twofold increased SMR for biliary tract cancer among female workers and for liver cancer among male workers compensated before 1970. CONCLUSIONS: The excess mortality from respiratory tract cancers and respiratory tract diseases detected in Italian compensated silicotics are in agreement with previous epidemiological studies. Although the twofold increased risk for liver cancer among males is suggestive of a possible association with silica dust exposure, the finding needs to be confirmed.

Exposures to silica mixed dust and cohort mortality study in tin mines: exposure-response analysis and risk assessment of lung cancer.

BACKGROUND: Mineral dusts that contain crystalline silica have been associated directly or indirectly with the development of pneumoconiosis or silicosis, non-malignant respiratory diseases, lung cancer, and other diseases. The health impacts on workers with silica mixed dust exposure in tin mines and dose-response relationships between cumulative dust exposure and the mortality from lung cancer are investigated. METHODS: A cohort of 7,837 workers registered in the employment records in 4 Chinese tin mines between 1972 and 1974 was identified for this study and the mortality follow-up was traced through 1994. Of the cohort, the cause of death was ascertained for 1,061 (97%) of the 1,094 deceased workers. Standardized mortality ratios (SMRs) were calculated for all workers, non-exposed workers, and dust-exposed workers with different exposure levels, silicotics, and non-silicotics based on Chinese national rates. RESULTS: The mortality from all causes in four tin mines was nearly the same as the national mortality. Malignant neoplasm, cerebrovascular disease, and cardiovascular disease accounted for 68.6% of all deaths. Mortality excess from lung cancer, liver cancer, all malignant diseases, and non-malignant respiratory diseases was observed among dust-exposed workers; a 50-fold excess of pneumoconiosis was observed. There was an upward trend for SMRs of lung cancer was noted from no exposure to low, medium, and high exposure levels (SMRs=1.29, 2.65, 2.66, 3.33). The shape of the exposure-response curve for risk of lung cancer at high exposure levels was inconsistent in these four mines. CONCLUSIONS: The findings indicated a positive dose-response relation between exposure to cumulative dust and the mortality of lung cancer. High arsenic content in dust particles, together with crystalline silica, may play an important role in causing increased mortality from lung cancer.

Pooled exposure-response analyses and risk assessment for lung cancer in 10 cohorts of silica-exposed workers: an IARC multicentre study.

OBJECTIVES: Silica is one of the most common occupational exposures worldwide. In 1997 the International Agency for Research on Cancer (IARC) classified inhaled crystalline silica as a human carcinogen (group 1), but acknowledged limitations in the epidemiologic data, including inconsistencies across studies and the lack of extensive exposure-response data. We have conducted a pooled exposure-response analysis of 10 silica-exposed cohorts to investigate lung cancer. METHODS: The pooled cohort included 65,980 workers (44,160 miners, 21,820 nominees), and 1,072 lung cancer deaths (663 miners, 409 nonminers). Follow-up has been extended for five of these cohorts beyond published data. Quantitative exposure estimates by job and calendar time were adopted, modified, or developed to permit common analyses by respirable silica (mg/m3) across cohorts. RESULTS: The log of cumulative exposure, with a 15-year lag, was a strong predictor of lung cancer (p = 0.0001), with consistency across studies (test for heterogeneity, p = 0.34). Results for the log of cumulative exposure were consistent between underground mines and other facilities. Categorical analyses by quintile of cumulative exposure resulted in a monotonic trend with odds ratios of 1.0. 1.0, 1.3, 1.5, 1.6. Analyses using a spline curve also showed a monotonic increase in risk with increasing exposure. The estimated excess lifetime risk (through age 75) of lung cancer for a worker exposed from age 20 to 65 at 0.1 mg/m3 respirable crystalline silica (the permissible level in many countries) was 1.1-1.7%, above background risks of 3-6%. CONCLUSIONS: Our results support the decision by the IARC to classify inhaled silica in occupational settings as a carcinogen, and suggest that the current exposure limits in many countries may be inadequate. These data represent the first quantitative exposure-response analysis and risk assessment for silica using data from multiple studies.

Respiratory cancer and other chronic disease mortality among silicotics in California.

Silicotics have increased mortality from tuberculosis (TB) and from nonmalignant respiratory diseases (NMRD), including silicosis and silicotuberculosis. Since the publication of the International Agency for Research on Cancer monograph in 1987 indicating that silica was a probable human carcinogen, there has been an extensive debate about the cancer risks among silicotics. The authors identified 590 claims for silicosis among a registry of lung diseases compiled from California Workers' Compensation cases from 1945 to 1975. Using state vital records, we determined the mortality risks from 1946 to 1991. Our findings confirmed that these claimants had a significantly elevated risk for all causes of death with a standardized mortality ratio (SMR) of 1.30 (95% confidence interval [CI] = 1.18, 1.43); TB had a SMR of 56.35 (95% CI = 41.10, 75.40) and NMRD a SMR of 3.80 (95% CI = 3.11, 4.60). Cancers of the trachea, bronchus, and lung had a SMR of 1.90 (95% CI = 1.35, 2.60). For malignancies of the large intestine, there was a previously unreported SMR of 2.08 (95% CI = 1.14, 3.50). Mortality from all diseases of the heart was significantly less than expected with a SMR of 0.68 (95% CI = 0.55, 0.83); cancers of the prostate and lymphatic system were also significantly low with SMRs of 0.26 (95% CI = 0.03, 0.94) and 0.17 (95% CI = 0.04, 0.97), respectively. Workers with silicosis should be warned about these chronic disease risks, and prevention efforts to control occupational silica dust exposure should become a higher priority.

Emphysema in silica- and asbestos-exposed workers seeking compensation. A CT scan study.

It has been established that coal pneumoconiosis and confluent silicosis are associated with emphysematous changes in the lungs. In the present study, we addressed the concept of emphysema in simple silicosis and asbestosis and in workers exposed to these minerals without the pneumoconiosis. The study was done on 207 consecutive workers evaluated for possible pneumoconiosis at Québec Workman Compensation Board, who had a radiographic reading of pneumoconiosis in the category 0 or 1 of the ILO scale, and in 5 control subjects. Emphysema was detected, typed, and graded on high-resolution CT scans by three independent experienced readers. Age, work experience and industry, smoking habits, and pulmonary function test results were analyzed for possible associations. The subjects were 59 +/- 1 years of age and had mineral dust exposure averaging 26 +/- 1 years; 31 were lifetime nonsmokers and the others were either ex- or current smokers. Ninety-six workers were from primary and 111 from secondary industries and did not differ in any parameter. The CT scan readings for emphysema yielded a 63% complete agreement. In lifetime non-smokers, emphysema was seen in 1 of 20 subjects without pneumoconiosis but in 8 of 11 patients with pneumoconioses. In smokers without pneumoconioses, emphysema was present in 55% of patients with silica exposure, but 29% of patients with asbestos exposure but comparable smoking (p = 0.04). Emphysema type was equally distributed among the groups except for more paracicatricial type in confluent silicosis. Regression analyses documented that age, smoking, exposure type, and presence of pneumoconiosis were significant contribution factors. In the workers without pneumoconiosis, age, smoking, and exposure type (silica) were significant. Emphysema related best with FEV1/FVC ratio, MMEF, and DCO reductions. The prevalence of abnormality of FEV1/FVC ratio was two to five times normal and that of reduced DCO two times normal. We conclude that, in our population, there was a significant excess of CT scan emphysema, associated with lung dysfunction, in those with pneumoconioses and in smokers with silica exposure. In the absence of smoking, it took a patient with pneumoconiosis to have emphysema. These changes contributed to the lung function impairment of these subjects with ILO category 0 or 1 pneumoconioses.

Lung cancer mortality and silicosis in Québec, 1938-85.

Men who had received compensation for silicosis in Québec between 1938 and 1985 were studied up to the end of 1986 to estimate risk of lung cancer mortality. Particular attention was paid to selection biases inherent in the study of such workers. Age-specific and calendar-year-specific mortality rates of Québec men from 1931 to 1985 were used for comparison. Risk of death from lung cancer in men who had received compensation for silicosis was more than 3 times higher than expected; silicosis may be a strong risk factor for lung cancer mortality.

Mortality of workers compensated for silicosis during the period 1959-1963 in the Veneto region of Italy.

After reports appeared from other countries indicating an excess risk of lung cancer among silicotics, a cohort of workers compensated for silicosis during the period 1959-1963 in the Veneto region of Italy was constructed and followed for mortality through 1984. The results of the study showed a large mortality excess for infectious diseases (180 observed versus 9.5 expected), due to silicotuberculosis, and for diseases of the respiratory system (270 observed versus 33.5 expected) due to silicosis. An elevated standardized mortality ratio of 239 (70 observed versus 29.3 expected) from lung cancer was also detected. An increasing pattern was observed with time since first exposure, while the relationship with employment category and duration of exposure was less clear-cut. The lung cancer excess was also strongly associated with cigarette smoking, there being a dose-response relationship with daily cigarette consumption. The study confirms the results from other epidemiologic studies on silicotics which show this pathological condition to be associated with increased lung cancer mortality.

[Bronchial cancer in anthracosilicosis and silicosis. Study of workers in coal fields in Wallonia]. / Le cancer bronchique chez les anthracosilicotiques et silicotiques. Etude chez les travailleurs des bassins houillers wallons.

This study was carried out between 1973 and 1982 on the proportional mortality by lung cancer of a group of workers living either in Brussells or in Wallonia and receiving compensation for silicosis or anthrasilicosis. The majority of patients suffered from anthrasilicosis (more than 96%) and had been exposed to the risk of pneumoconiosis in one of the four coal fields in Wallonia. If, in 13,822 deaths studied the proportional mortality from lung cancer had grown by 0.56% per year reaching 3.7% in 1973 and 9.3% in 1982, it remained below that for a similar Belgian population matched for age and sex. No correlation could be found between the occurrence of this tumour and one or other radiological category as defined by the international classification of pneumoconiosis in 1980. In addition the severity of pneumoconiosis, either from a radiological or functional view, hardly had any influence on the genesis of lung cancer. Finally, the localisation of the tumour and the different histological types do not differ from that reported in the literature among the general population. On the other hand a significant rise in proportional mortality from lung cancer between 1973 and 1982 (p less than 0.001) seemed to be related to two factors, smoking habitis (89.1% of subjects dying from lung cancer were smokers at the moment of death against 68.5% of smokers among other causes of death), and above all the progressive aging of the population of pneumoconioties receiving compensation, the cross section 50-69 rose from 53.17% in 1973 to 73.8% in 1982.

Electrocardiographic signs of chronic cor pulmonale in 40 376 patients with silicosis.

The records of all patients who were examined for silicosis at the Fund of Occupational Diseases between 1972 and 1976 are reviewed. In 3627 cases the mechanographical record was incomplete leaving 40 376 patients in the study. Electrocardiographic signs of chronic cor pulmonale (C.C.P.) were detected in 5.58 per cent. The severity of C.C.P. was evaluated and the prevalence of the different electrocardiographic signs was examined. The presence and severity of C.C.P. was compared to the radiological stage of silicosis, to the pulmonary function, to the duration of professional exposure to the risk of silicosis and to the use of tobacco. The value of the electrocardiographic signs of C.C.P. was evaluated. It is concluded that the mechanographical record obtained in insurance medicine is a valuable tool for statistical analysis of a disease and that C.C.P. is an infrequent and mostly late complication of silicosis.