The Blood Lead, Blood Pressure Connection: An Evaluation of Apparently Healthy Lead Exposed Workers in Nigeria

Objective: There is a paucity of evidence on the lead exposure and blood pressure association in Nigeria where lead exposure is still prevalent and poorly regulated. The objective of this study was to evaluate the association between lead exposure using blood lead level and blood pressure in Port Harcourt Nigeria. Methodology: A prospective cross sectional comparative study of adult subjects with occupational lead exposure and controls, performed in Port Harcourt, South-south Nigeria. Blood lead measured by atomic absorption spectrophotometry was used as the biomarker of lead exposure while systolic and diastolic blood pressures and other relevant variables were measured and analysed. Results: The mean systolic blood pressure was significantly higher in lead exposed subjects 118.49 (14.67) mmHg compared to controls 113.62 (11.31) mmHg (p = 0.008). No difference was observed in the mean diastolic blood pressure. A higher proportion of subjects had systolic and diastolic pressure > 140 mmHg and >90 mmHg compared to controls 9.47% vs. 1.25% and 10.51% vs. 2.54%, with (p = 0.016), OR = 8.27 < 1.14 < OR < 169.09>, RR = 1.38 < 1.21 < RR < 1.58> and (p = 0.028), OR = 4.59 < 1.00 < OR < 29.15>, RR = 1.33 < 1.13 < RR < 1.55> respectively. There was no significant statistical correlation between blood lead and blood pressure. Conclusion: The results of this study indicate a significant systolic blood pressure elevation and prevalence of hypertension among lead exposed workers in Port Harcourt Nigeria. Lager longitudinal research is needed to evaluate lead exposure and elevated blood pressure association in Nigeria. The findings call for better regulation of occupational lead exposure in Nigeria.