The Association of Prolonged QT Interval on Electrocardiography and Chronic Lead Exposure
Objectives The aim of this study was to examine the association of lead exposure with cardiac conduction disturbance among lead-exposed and nonexposed workers in Taiwan.
Methods The participants comprised 312 lead workers and 329 referents who had no known occupational lead exposure. During their annual health examination, they were invited to take part in the survey. Standard resting 12-lead electrocardiograms were obtained and the electrocardiographic features studied were related to blood lead levels (BLLs).
Results The mean BLLs were 26.05 (SD = 13.98) and 2.62 (SD = 1.42) μg/dL in lead-exposed and reference groups, respectively. Compared with the referents, lead workers had significantly shorter PR interval and longer QTc interval. Especially, workers with BLL > 30 μg/dL had the highest risk after adjusting for age, sex, body mass index, and other potential confounders.
Conclusion The data suggest that lead exposure is positively associated with prolonged QTc interval.