Background and objective:We recently noted a dramatic increase in the number of patients with accelerated silicosis associated with exposure to artificial stone dust. Therefore, the natural history of artificial stoneassociated silicosis was compared with that of natural stone-associated silicosis. Methods: A total of 18 patients with artificial stoneassociated silicosis and 63 with natural stone-associated silicosis were diagnosed sequentially in 2018 and followed up for a period of 6-12 months. Data were collected from clinical charts. Results: The median duration of exposure prior to onset of symptoms of silicosis was shorter for patients who had been exposed to artificial stone dust (6.4 vs 29.3 years, P < 0.01). Four of the 18 patients experienced rapid deterioration in lung function over the follow-up period, with declines in pre-bronchodilator FVC of 587 (210-960) mL/year and FEV 1 of 625 (360-860) mL/year. GGO, PMF, emphysema and pulmonary artery widening were more frequently observed on computed tomography scans of patients with artificial stone-associated silicosis than of those with natural stone-associated silicosis. Approximately 38.9% of the patients with artificial stone-associated silicosis were lung transplant candidates and 27.8% died, both rates being significantly higher than in patients with natural stone-associated silicosis (3.2% and 0%, both P < 0.01). Conclusion: Compared to natural stone-associated silicosis, artificial stone-associated silicosis was characterized by short latency, rapid radiological progression, accelerated decline in lung function and high mortality. SUMMARY AT A GLANCEHigh silica content of artificial stone and uncontrolled dry cutting and grinding presents as a high risk of developing accelerated silicosis. Compared to natural stone-associated silicosis, artificial stoneassociated silicosis was characterized by short latency, rapid radiological progression, accelerated decline in lung function and high mortality in this study.

ObjectivesOccupational dust exposure may induce various lung diseases, including pneumoconiosis and chronic obstructive pulmonary disease (COPD). The features of combined COPD and pneumoconiosis have not been well described, and this may hamper the management. This study aimed to describe the prevalence and characteristics as well as the risk factors of the combined diseases.DesignA cross-sectional study.Setting and participants758 patients with pneumoconiosis were recruited at a single-medical centre. Of these, 675 patients with pneumoconiosis, including asbestosis, silicosis, coal workers’ pneumoconiosis and other pneumoconiosis, was eligible for analysis.Primary outcome measuresCOPD was diagnosed based on clinical features and/or history of exposure to risk factors and post bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio <0.7. Clinical data were collected from predesigned medical reports. The patients underwent both chest radiograph and high-resolution CT scans. Risk factors for combined COPD and pneumoconiosis were analysed using regression analysis.ResultsCOPD prevalence overall was 32.7% (221/675) and was the highest in silicosis (84/221) and coal workers’ pneumoconiosis (100/221). COPD prevalence increased with smoking pack-years, dust exposure duration and pneumoconiosis stage. Patients with combined diseases had lower body mass index, higher smoking index and worse pulmonary function. Risk factors for combined diseases included heavy smoking, silica or coal exposure and advanced pneumoconiosis. The interaction between dust exposure and smoking in COPD was also identified. The risk of combined COPD significantly increased with heavy smoking and silica or coal exposure (OR 5.49, 95% CI 3.04 to 9.93, p<0.001).ConclusionsCOPD is highly prevalent in patients with pneumoconiosis, especially patients with silicosis and coal workers’ pneumoconiosis. Occupational dust exposure as well as heavy smoking is associated with an increased risk of combined COPD and pneumoconiosis, which demands an effective preventive intervention.

Abstract Background: Interstitial pneumonia (IP) is one of the common pulmonary complications of idiopathic inflammatory myopathy (IIM), among which myositis-specific autoantibodies (MSA) are specific for IIM diagnosis and prognosis. However, IP patients with MSA (MSA-IP) have not been well described. The study aimed to explore the phenotypic clusters and prognosis of MSA-IP patients.Methods: A total of 124 MSA-IP patients were prospectively enrolled for analysis. Serum MSA were detected using immunoprecipitation. Radiographic patterns of IP were determined according to the classification of idiopathic IPs. The clusters of MSA-IP patients were identified using cluster analysis. Potential risk factors of acute onset and short-term prognosis were also analyzed. Results: There were four clusters of MSA-IP patients. Cluster 1 patients were elders with chronic onset and usual interstitial pneumonia pattern on CT scan. Cluster 2 patients were all positive for anti-aminoacyl-tRNA antibodies, predominantly females and had frequent respiratory symptoms. Patients of cluster 3 showed multi-system involvements with nonspecific interstitial pneumonia pattern. Patients of cluster 4 had severe respiratory symptoms with anti-MDA5. The patients of cluster 3 (OR 6.682, 95% CI 1.560–28.622, P=0.011) or cluster 4 (OR 6.057, 95% CI 1.715–21.388, P=0.005) were susceptible to acute onset. The patients of cluster 4 were prone to disease progression (HR 2.711, 95% CI 1.128–6.519, P=0.034), which was consistent with the Kaplan–Meier curves.Conclusions: Four distinctive clusters were determined by cluster analysis suggesting the characteristics, serological antibodies and prognosis of MSA-IP.