Risk Factors for Mortality in Denim Sandblasters Silicosis: Selecting Candidate for Lung Transplantation

Abstract

Objective: This study aimed to review the risk factors for silicosis together with survival analysis and a perspective for lung transplantation with data from a single center.

Material and methods: We reviewed the medical records of denim sandblasters who were referred to our center between January 2006 and December 2011 and evaluated 219 patients with a history of denim sandblasting with a minimum follow-up period of 5 years until 2016. We analyzed several personal and occupational features, together with functional and radiologic data.

Results: Of the 219 denim sandblasters, 107 (49%) had been diagnosed with silicosis. In the logistic regression analysis, the duration of exposure was the only independent risk factor for the development of silicosis, indicating a 9% increased risk of silicosis for every month of exposure (p<0.001; odds ratio 1.09; 95% confidence interval 1.050-1.132). Of the patients, 7 (3%) died. A forced expiratory volume in the first second of <44% and a forced vital capacity of <47% were associated with an increased risk of mortality. Mortality was significantly higher in the international labor office category 3 patients, and 5-year survival rates of patients with A, B, and C lung opacities were 88%, 67%, and 25%, respectively.

Conclusion: Silicosis still kills young workers. Severe radiologic involvement and decreased lung volumes are related to mortality, and lung transplantation is the only therapeutic option.

Figure 1

Receiver Operating Characteristic analysis of FEV1 and FVC for mortality

Figure 2

Kaplan-Meier Survival analysis comparing ILO categories ≤2 and 3

Figure 3

Kaplan-Meier Survival analysis comparing presence and absence of a large opacity