Table 3.
Association with an interquartile (15 μg/g) increase in tibia lead biomarkers on change in MMSE score by class of HFE genotype.
| Model/class of HFE genotype | Unadjusted mean difference in annual rate of change in MMSE (95% CI) | Adjusteda mean difference in annual rate of change of MMSE (95% CI) | p-Value interaction | p-Value trend |
|---|---|---|---|---|
| Model 1: binary | 0.03b | NA | ||
| Wild-type | –0.02 (–0.10 to 0.05) | –0.02 (–0.10 to 0.07) | ||
| Any HFE variant allele | –0.23 (–0.40 to –0.07) | –0.22 (–0.39 to –0.05) | ||
| Model 2: dose | < 0.01c | < 0.01 | ||
| Wild-type | –0.02 (–0.10 to 0.05) | –0.02 (–0.10 to 0.07) | ||
| One HFE variant allele | –0.15 (–0.33 to 0.03) | –0.14 (–0.33 to 0.04) | ||
| Two HFE variant alleles | –0.62 (–1.03 to –0.22) | –0.63 (–1.04 to –0.21) |
NA, not applicable.
a
Adjusted for age, years of education, nonsmoker, former smoker, pack-years, nondrinker, alcohol consumption, English as first language, computer experience, and diabetes.
b
p-Value for tibia lead and any HFE variant allele interaction.
c
p-Value for tibia lead and two HFE variant alleles interaction.