Background: Development of silicosis is a global occupational hazard, characterized by progressive and irreversible deterioration of lung function. Established associations between the decreased lung function and low-grade systemic inflammation place adults with silicosis at extreme risk of developing DM, but little is known about the prevalence of DM and potential risk factors of DM among adults with silicosis.
Methods: We enrolled 390 Chinese adults (mean age=68.7±7.8, men=99.5%) with confirmed silicosis by the Pneumoconiosis Medical Board. The Compensation Ordinance determines the degree of incapacity (DOI), according to lung function loss based on the forced vital capacity. Diagnosed DM by a medical practitioner/physician. Occupational information included job type and duration of dust exposure. Validated questionnaires were used to measure respiratory symptoms, activity limitation and physical activity level. Insulin resistance, fasting glucose, high sensitivity C-reactive protein (hs-CRP), lipid profiles, and vitamin C were via 8-hour fasting venous sample. Body mass index, waist circumference, body fat mass percentage and blood pressure were measured. Logistic regression model was used to adjust covariates of DM.
Results: The prevalence of DM among adults with silicosis was 18.5% (n=72), which is higher than the general Chinese male population (Hong Kong=11.4%; China=12.1%). Participant characteristics according to DOI are presented in Table 1. After adjusting for hs-CRP, age, education and physical activity level, body fat mass percentage, medication use for lipid and blood pressure control, higher DOI was significantly associated with higher odds of DM (OR=1.65, 95%CI=1.08-2.53).
Conclusion: Adults with longer duration of silicosis have an intensifying risk of DM development. Rehabilitation programs for this vulnerable group with impaired lung function need to target cardiometabolic risk factors to reduce development of CVD.