Air Quality Criteria for Lead Volume II of II - (NEPIS)(EPA) - US ...

AX6-136
Table AX6-5.1 (cont’d). Effects of Lead on Blood Pressure and Hypertension
Reference, Study
Location, and
Period Study Description Pb Measurement Findings, Interpretation
United States (cont’d)
Korrick et al.
(1999)
U.S.-Boston-Nurse
Health Study
1993-1995
Morris et al. (1990)
U.S.-sampled from
general population
around Portland,
OR responding to
ads to participate in
clinical trials of
nonpharmacological
management of
blood pressure.
1984-1989?
284 women, from 47-74 yrs, mean age
(SD) 58.7 (7.2), were divided into 97
cases (systolic ∃140 mm Hg,
diastolic ∃90 mm Hg, or physiciandiagnosed
hypertension) and
195 controls. Controls were further
classified as low normal
(121/75 mm Hg). Three ordinal
regression models were constructed,
each containing either blood Pb, tibia Pb
or patella Pb with forced entry of all
other covariates. A final backwards
elimination ordinal regression model
started with all covariates, including all
Pb variables, excluding each until only
significant variables were left.
Interactions were tested in the final
model between patella Pb and alcohol
use, age, and menopausal status.
145 males and 106 females, 73% with
arterial pressures >105 mm Hg,
provided blood pressure measurements
once a wk over four consecutive wks.
Blood for Pb analysis was collected
during this period. Stepwise multiple
regression was used to construct
separate models of systolic and diastolic
blood pressure stratified by sex.
Covariates available to be entered were
age, BMI, dietary calcium and “other
nutrient intakes,” ionized serum
calcium, erythrocyte protoporphyrin and
natural log transformed blood Pb.
Mean blood Pb (SD, range):
3.1 µg/dL (2.3,