Longitudinal analysis of chronic occupational exposure in insulators

Cardiovascular and respiratory diseases are among the global leading causes of mortality. Insulators are at risk of these illnesses because of chronic exposure to asbestos and silica. In this study, a longitudinal analysis was carried out to determine the effect of asbestos exposure on the lung and cardiac health of insulators. Unionized insulators (n = 894) were assessed in Alberta (45 ± 14 years) and full physical assessments, family, health, and work histories were collected along with pulmonary function tests, chest X-rays, Framingham cardiac risk scores, and COPD assessment test (CAT) scores. Subjects were followed up, approximately every 2 years, with 894 in 1st, 426 in 2nd, 149 in 3rd, and 21 in 4th visits. At baseline, 63% of the cohort was exposed to asbestos, and 66% had a history of smoking. FEV1 and FEV1/FVC declined over time for insulators, with an additional decrement for smokers. CAT scores were elevated in smokers and insulators exposed to asbestos that used some or no personal protection equipment. Framingham scores increased each year independent of age. Baseline asbestos exposure and smoking were significant risk factors for increased Framingham risk scores. The incidence rate of developing X-ray-detected lung abnormalities, COPD, and asbestos-related lung diseases were 5.3, 4.4, and 0.8 per 100 person-year, respectively. Our findings show significant declines in lung function, increased risk of cardiac diseases, and elevated rates of lung diseases over a period of 4 ± 1 years in insulators. This study is still in progress to increase sample size, but already we have found evidence that more needs to be done to protect the health of workers and prevent the onset of lung and cardiac diseases.