Central hemodynamics in relation to blood lead in young men prior to chronic occupational exposure

Abstract

Background: Aortic pulse wave velocity (aPWV) predicts cardiovascular complications, but the association of central arterial properties with blood lead level (BL) is poorly documented. We therefore assessed their association with BL in 150 young men prior to occupational lead exposure, using baseline data of the Study for Promotion of Health in Recycling Lead (NCT02243904).

Methods: Study nurses administered validated questionnaires and performed clinical measurements. Venous blood samples were obtained after 8–12 h of fasting. The radial, carotid and femoral pulse waves were tonometrically recorded. We accounted for ethnicity, age, anthropometric characteristics, mean arterial pressure, heart rate, smoking and drinking, and total and high-density lipoprotein serum cholesterol, as appropriate.

Results: Mean values were 4.14 μg/dL for BL, 27 years for age, 108/79/28 mm Hg for central systolic/diastolic/pulse pressure, 100/10% for the augmentation ratio/index, 1.63 for pressure amplification, 5.94 m/s for aPWV, 27/11 mm Hg for the forward/backward pulse pressure height, and 43% for the reflection index. Per 10-fold BL increase, central diastolic pressure and the augmentation ratio were respectively 5.37 mm Hg (95% confidence interval [CI], 1.00–9.75) and 1.57 (CI, 0.20–2.94) greater, whereas central pulse pressure and the forward pulse pressure height were 3.74 mm Hg (CI, 0.60–6.88) and 3.37 mm Hg (CI, 0.22–6.53) smaller (p ≤ .036 for all). The other hemodynamic measurements were unrelated to BL. The reflected pulse peak time was inversely correlated with diastolic pressure (r = −0.20; p ≤ .017).

Conclusion: At the exposure levels observed in our current study, aPWV, the gold standard to assess arterial stiffness, was not associated with BL. Increased peripheral arterial resistance, as reflected by higher diastolic pressure, might bring reflection points closer to the heart, thereby moving the backward wave into systole and increasing the augmentation ratio in relation to BL.

Keywords:

• Aortic pulse wave velocity
• arterial stiffness
• central blood pressure
• central hemodynamics
• lead
• occupational medicine

Acknowledgements

The authors gratefully acknowledge the nursing staff employed at the study sites in the United States and the expert clerical assistance of Vera De Leebeeck and Renilde Wolfs at the Studies Coordinating Centre in Leuven, Belgium.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The European Union [HEALTH-F7-305507 HOMAGE] and the European Research Council [Advanced Researcher Grant 2011-294713-EPLORE and Proof-of-Concept Grant 713601-uPROPHET], the European Research Area Net for Cardiovascular Diseases [JTC2017-046-PROACT], and the Research Foundation Flanders, Ministry of the Flemish Community, Brussels, Belgium [G.0881.13] currently support the Research Unit Hypertension and Cardiovascular Research. An unrestricted grant from the International Lead Association (www.ila-lead.org) partially supports the data collection and analysis of the current data. The sponsors had no role in the preparation of this report.