A Meta-analysis of the Association between Blood Lead and Blood Pressure

Koh, Sang Baek; Kim, Chun Bae; Nam, Chung Mo; Choi, Hong Ryul; Cha, Bong Suk; Park, Jong Ku; Jee, Ho Sung

Abstract

OBJECTIVES
To integrate the results of studies which assess an association between blood lead and blood pressure.
METHODS
We surveyed the existing literature using a MEDLINE search with blood lead and blood pressure as key words, including reports published from January 1980 to December 2000. The criteria for quality evaluation were as follows: 1) the study subjects must have been workers exposed to lead, and 2) both blood pressure and blood lead must have been measured and presented with sufficient details so as to estimate or calculate the size of the association as a continuous variable. Among the 129 articles retrieved, 13 studies were selected for quantitative meta-analysis. Before the integration of each regression coefficient for the association between blood pressure and blood lead, a homogeneity test was conducted.
RESULTS
As the homogeneity of studies was rejected in a fixed effect model, we used the results in a random effect model. Our quantitative meta-analysis yielded weighted regression coefficients of blood lead associated with systolic blood pressure and diastolic blood pressure results of 0.0047 (95% confidence interval [CI]: -0.0061, 0.0155) and 0.0004 (95% CI: -0.0031, 0.0039), respectively.
CONCLUSIONS
The published evidence suggested that there may be a weak positive association between blood lead and blood pressure, but the association is not significant.