Correlation of Blood Lead Levels and Elevated Blood Pressure in Newly Detected Hypertensive Patients

Abstract

BACKGROUND Hypertension is one of the most common diseases all over the world. Lead is a common environmental and industrial pollutant with no beneficial biological role. The contribution of environmental lead exposure to hypertension is an important public health concern. The objective of this study was to determine the blood lead levels in hypertensive patients and to investigate the correlation between blood lead (B-Pb) levels and the values of blood pressure in hypertensive patients. METHODS This is a hospital based analytical cross-sectional study conducted over a period of one and half years. Subjects included 50 newly detected hypertensive and 50 healthy subjects recruited who were both age and sex matched. Mean of age, blood lead levels, systolic blood pressure (SBP), diastolic blood pressure (DBP) with standard deviation were assessed. Linear regression was used to estimate the predicted systolic blood pressure (BP) and diastolic BP with lead levels. Pearson correlation was used to estimate the correlation between blood lead and blood pressure levels. RESULTS In this study, 52 % of cases and controls were in the age group of 41 - 60 years. 22 % of the subjects were more than 61 years of age. 45 % of the total subjects were females and 55 % were males. 46 % of the controls and 44 % of the cases were females. Comparison of the serum lead levels (mcg / dl) between cases and controls showed that serum lead levels (mcg / dl) were higher in Cases group with a t-value of -7.38 and was statistically significant with a P-value of < 0.001. Comparison of the serum lead levels (mcg / dl) between the males and females showed that serum lead levels (mcg / dl) were higher in female group with a t-value of - 0.151 and was statistically non-significant with a P-value of 0.881. This study showed that there is an increase in blood lead levels in hypertensive patients compared to the control group. Stage 2 hypertension has higher serum lead level value of 21.228 compared to stage 1. Serum lead levels were higher in females compared to males. CONCLUSIONS Our study indicated that blood lead level is significantly and positively correlated to blood pressure among newly detected hypertensive patients. Increase in blood lead levels causes increase in both systolic and diastolic blood pressures. KEY WORDS Hypertension, Lead, Systolic Blood Pressure, Diastolic Blood Pressure