The survival analyses of 2738 patients with simple pneumoconiosis

Prognostic Implication of Exfoliative Airway Pathology in Cancer-Free Coal Workers' Pneumoconiosis

BACKGROUND

The purpose of this study is to see if exfoliative pulmonary airway pathology in cancer-free coal workers' pneumoconiosis (CWP) can be used as a biomarker for predicting pulmonary morbidity.

METHODS

We investigated persistent metaplastic changes in bronchoscopic washing cytology and differential cell counts in bronchoalveolar lavages (BAL) in 97 miners with CWP and 80 miners without CWP as the control. Clinicopathological parameters were examined including pulmonary function tests and the presence of progressive massive fibrosis.

RESULTS

When compared to the control group, severe alveolitis, severe goblet cell hyperplasia (GCH), severe hyperplastic epithelial change, and severe squamous metaplasia were the distinguishing biomarkers in CWP. Multivariate analysis revealed that severe alveolitis and severe GCH, along with miner duration and current smoker, were independent predictors of pulmonary mortality. The survival analysis revealed a significantly different survival rate between the three groups: no evidence of severe alveolitis and severe GCH, presence of severe alveolitis or severe GCH but not both, and both severe alveolitis and severe GCH.

CONCLUSIONS

The severities of alveolitis and goblet cell hyperplasia in the bronchoscopic study are independent prognostic factors for CWP. A pathologic grading system based on these two parameters could be used in the stratification and clinical management of CWP patients.

Influence of duration and intensity of exposure to occupational hazards on mortality levels of coal miners

Th e article presents results of analytic epidemiologic study of mortality in coal miners cohort in Rostov region, who had occupational disease registered in various years. The cohort included 9980 males, the observation period was 26 years (01/01/1990–31/12/2015). Deep analysis of mortality with leading death causes in subgroups of coal miners differentiated by length of service in underground conditions. Standardized relative risk of death in the subgroups increased with longer length of service, with respiratory diseases, circulatory system diseases and malignancies.

The authors studied mortality in subcohorts of the miners with leading and auxiliary occupations, whose work conditions differ in intensity of exposure to occupational hazards. For the workers with leading occupations, standardized relative risk of death with respiratory diseases, circulatory system diseases and malignancies was higher.

Prognostic effect of tuberculosis on patients with occupational lung diseases: A 13-year observational study in a nationwide cohort

Occupational lung diseases are well recognized risk factors for tuberculosis (TB). However, little research investigated the effect of TB on the clinical course and outcome of occupational lung diseases.We conducted a 13-year observational study of a nationwide cohort to evaluate the risk and prognosis of TB among patients with occupational lung diseases in Taiwan.By using the Taiwan National Health Insurance database, occupational lung diseases cohort was identified according to diagnosis codes from 1998 to 2008 and prospectively monitored until the end of 2010, loss to follow-up, or death. Newly diagnosed TB, comorbidities, and demographic characteristics were evaluated as prognostic variables in the survival analysis of patients with occupational lung diseases using Cox proportional hazard regression models.A total of 12,787 study participants were enrolled with an average of 9.69 years of follow-up. Among them, 586 (4.58%) had newly diagnosed TB and 3180 (24.87%) died during follow-up. The incidence of TB was 473 per 100,000 person-years, and the risk of TB infection significantly increased over time. The independent risk factors for mortality included male gender (hazard ratio [HR]: 2.23, 95% confidence interval [CI]: 1.91-2.60), age (HR: 1.05, 95% CI: 1.05-1.06), TB (HR: 1.17, 95% CI: 1.01-1.37), congestive heart failure (HR: 1.44, 95% CI: 1.17-1.79), cerebrovascular disease (HR: 1.34, 95% CI: 1.15-1.57), chronic obstructive pulmonary disease (HR: 1.44, 95% CI: 1.33-1.56), and asthma (HR: 1.27, 95% CI: 1.15-1.40). In addition, patients with TB infections had worse outcomes in the survival analysis than those without TB (log-rank test P = 0.02).Despite the low prevalence of occupational lung diseases in Taiwan, patients with those diseases had a higher TB incidence than the general population did (473 vs 55 per 100,000 person-years). Furthermore, even with effective antimicrobial chemotherapy, TB infection was a prognostic factor leading to poor outcomes in the patients with occupational lung diseases. We recommend intensive medical surveillance of TB in these high-risk patients for better control of TB and improvement of occupational health in Taiwan.

Risk factors associated with mortality from pneumonia among patients with pneumoconiosis

BACKGROUND

The aim of this study was to evaluate factors associated with increased risk of mortality from pneumonia among patients with pneumoconiosis.

METHODS

Medical records of 103 pneumoconiosis patients hospitalized for pneumonia were investigated. Seven patients who had lung cancer or other malignancy and 13 patients with insufficient medical record were excluded. Two female patients were excluded due to small number to analyze. The subjects were divided into two groups by clinical outcome of pneumonia, the deceased group and the survival group. The two groups were compared in terms of age, smoking history, episode of recent pneumonia, concomitancy of interstitial fibrosis or fungal ball infection, extent of small opacities, grade of large opacities and results of spirometry. Multiple logistic regression was applied to determine the association between these variables and mortality from pneumonia.

RESULTS

The deceased group showed more frequent history of recent pneumonia (p = 0.006), higher prevalence of interstitial fibrosis (p = 0.007) and longer hospitalization period (p = 0.044). The proportion of subjects who had decreased FVC, less than 70 % of predicted value, was higher in the deceased group (p < 0.001). In multiple logistic regression, after adjusting age, smoking history, recent pneumonia, fungal ball, large opacity, profusion and FVC (or FEV1) less than 70 % of predicted value, history of recent pneumonia, concomitancy of interstitial fibrosis, type of pneumoconiosis and fungal ball presented statistically significant association with mortality from pneumonia.

CONCLUSIONS

The concomitancy of fungal ball or interstitial fibrosis, history of recent pneumonia within last 90 days, type of pneumoconiosis, FVC less than 70 % of predicted value, FEV1 less than 70 % of predicted value presented statistically significant association with mortality from pneumonia. More attention should be given to patients who have such factors when treating pneumonia with pneumoconiosis.

Update on respiratory disease from coal mine and silica dust

Coal mine and silica dust cause significant respiratory disease in spite of modern dust control regulations. Susceptible individuals in exposed populations may develop fibrosing lung disease, obstructive airways disease, including chronic bronchitis and emphysema, or lung cancer. A careful occupational history that elicits exposure to respiratory hazards is the cornerstone of an accurate diagnosis. Treatment involves removal from exposure, supportive care, pulmonary rehabilitation, and when disabling disease is present, assistance obtaining compensation.

Relationship between Asbestos Exposures and 8-Hydroxydeoxyguanosine Levels in Leukocytic DNA of Workers at a Chinese Asbestos-material Plant

The objective of the study was to evaluate the level of 8-hydroxydeoxyguanosine (8-OHdG) in DNA of peripheral-blood leukocytes as a biological marker of asbestos exposure and/or its fibrotic effects in an occupational population exposed to asbestos. The setting was a large-scale asbestos plant in China producing brake linings, asbestos rubber, and textile using chrysotile. From a base population of active and retired workers with various levels of cumulative exposure to asbestos and grades of asbestosis, 39 study subjects were randomly selected to reflect incremental grades of asbestosis based on Chinese diagnostic standards. They consisted of 19 "normal" (control) and ten "suspected" and ten "definite" asbestosis-grade subjects, group-matched for age and sex. Leukocytic DNA was extracted from 5-mL samples of peripheral blood and 8-OHdG level measured by high-pressure liquid chromatography. A cumulative asbestos exposure index (CEI) was calculated for each subject as the summed product of duration and level of asbestos exposure per job, incorporating a job-exposure matrix. Geometric mean 8-OHdG levels showed a positive gradient in relation to increasing grades of asbestosis (control: 1.78, suspected: 2.21, definite: 2.58), with a significant difference between the control and definite-asbestosis subgroups (p < 0.05). The 8-OHdG level of the two subgroups combined as one "asbestosis" group was significantly higher than that of the control group (control: 1.78, asbestosis: 2.39, p = 0.01). Further, 8-OHdG levels were moderately correlated with CEIs for all subjects (r = 0.35, p < 0.05) and with grades of asbestosis for all (r = 0.47, p < 0.01) and for male subjects (r = 0.43, p < 0.05). In multiple regression analyses, grade of asbestosis explained 27% of the total variation in 8-OHdG and was a better predictor than CEI or duration of exposure. Thus, the 8-OHdG level in leukocytic DNA is related to grade of asbestosis and to individual cumulative exposure and may serve as a biologic marker reflecting the status of oxidative DNA damage by asbestos.