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

AX6-74
Table AX6-4.1 (cont’d). Renal Effects of Lead in the General Population
Reference, Study
Location, and
Period Study Description Pb Measurement Findings, Interpretation
United States (cont’d)
Wu et al. (2003a)
Boston, MA
1991-1995
709 men enrolled in the Normative Aging Study.
Serum creatinine
1.2 mg/dL
Calculated creatinine clearance
71.3 mL/min
Serum uric acid
6.5 mg/dL
Multiple linear regression, adjusting for age, body
mass index, blood pressure or HTN (depending on
model), and alcohol ingestion. Uric acid models also
adjusted for serum creatinine, other outcome models
adjusted for smoking status and analgesic medication
use.
Mean (SD) blood Pb
6.2 (4.2) µg/dL
Mean (SD) tibia Pb
22 (13.4) µg/g bone mineral
Mean (SD) patella Pb
32.1 (19.5) µg/g bone mineral
Significant inverse association between patella Pb and
creatinine clearance.
∃ = !0.069, SE not provided
Borderline significant (p = 0.08) inverse association
between tibia Pb and creatinine clearance. Borderline
significant (p = 0.08) positive associations between tibia
and patella Pb and uric acid. No Pb measure significantly
associated with serum creatinine.
ALAD gene polymorphism also assessed. 114
participants had the ALAD2 variant allele (7 were
homozygous). None of the three renal outcomes differed
by genotype. Effect modification by genotype on the
association between tibia Pb and serum creatinine was
observed; the beta coefficient (and slope) was greater in
the group with the variant allele (∃ = 0.002 [SE not
provided]; p = 0.03).
Effect modification of borderline significance (p < 0.1) on
relations between of patella and tibia Pb with uric acid was
observed; this was significant in participants whose patella
Pb levels were above 15 μg/g bone mineral (∃ = 0.016 [SE
not provided]; p = 0.04 ). Similar to the serum creatinine
model, patella Pb was associated with higher uric acid in
those with the variant allele. Genotype did not modify Pb
associations in models of estimated creatinine clearance.