Abstract

The contribution of lead exposure to cardio-cerebrovascular disease is not yet fully understood. We examined the prospective associations of graded blood lead level (BLL) with hospital admission duo to cardio-cerebrovascular diseases among the lead-exposed male workers in Korea.

This cohort was constructed lead-exposed male workers who underwent a lead-associated medical check-up at least once between January 1, 2000 and December 31, 2004. The cardio-cerebrovascular disease based on hospital admission records were matched from 2000–2005 National Health Insurance Claim Data (NHICD). We used Cox proportional hazards models to estimate adjusted admission hazard ratio (AHR) for cardio-cerebrovascular diseases. Each BLL grade’s (10 to 20 μg/dl and ≥20 μg/dl) relative risks were compared with the reference grade (<10 μg/dl).

The AHR (1.86, 95% CI: 1.22–2.84) of the ischaemic heart diseases (IHD) was significantly higher in the workers with BLL ≥ 20 μg/dl than with BLL ≤ 10 μg/dl. The AHR (1.54, 95% CI: 1.07–2.33) of cerebrovascular diseases was significantly higher in the workers with BLL 10 to 20 μg/dl than with BLL ≤ 10 μg/dl. There were a significant positive linear trend based on BLL grade in the IHD and cerebrovascular diseases.

This large prospective cohort with over fifty thousand lead exposed workers showed the probable causal relations between BLLs (with ≥20 μg/dl) and clinically diagnosed cardio-cerebrovascular diseases.