Table 3.
Estimates of magnitudes of the “progressive” tibia lead associations with outcomes, Baltimore Memory Study, 2001-2005. Results are presented only for results with associated p-values < 0.10 in Table 2. Where not noted relationships are linear.
| Domain | Effect | Base Model1 Mean (95% CI) domain score difference per 12.7 μg/g tibia lead2 | Race- and SES-adjusted3 Mean (95% CI) domain score difference per 12.7 μg/g tibia lead2 |
|---|---|---|---|
| All study subjects, N = 964 | |||
| Eye-hand coordination | Baseline lead comparison Yearly difference amplification |
-0.089 (-0.139, -0.039) -0.019 (-0.031, -0.007) |
-0.005 (-0.052, 0.042) -0.019 (-0.031, -0.007) |
| African-Americans subjects only, N = 394 | |||
| Eye-hand coordination | Baseline lead comparison Yearly difference amplification |
0.010 (-0.072, 0.092) -0.032 (-0.052, -0.012) |
0.028 (-0.052, 0.108) -0.032 (-0.052, -0.012) |
| White subjects only, N = 517 | |||
| Eye-hand coordination | Baseline lead comparison Yearly difference amplification |
-0.076 (-0.136, -0.016) -0.009 (-0.024, 0.006) |
-0.052 (-0.109, 0.005) -0.009 (-0.024, 0.006) |
| Verbal memory & learning4 | Baseline lead comparison – low to moderate Baseline lead comparison – high vs. low/mod Yearly difference amplification – low to moderate Yearly difference amplification – high vs. low/mod |
-0.257 (-0.446, -0.067) 0.217 (-0.057, 0.491) 0.056 (-0.004, 0.116) -0.085 (-0.160, -0.010) |
-0.239 (-0.423, -0.055) 0.236 (-0.035, 0.508) 0.056 (-0.004, 0.116) -0.086 (-0.161, -0.012) |
The Base Model adjusted for age, sex and interviewer.
12.7 μg/g is the IQR of tibia lead among individuals with non-negative concentrations (n=965).
The race/ethnicity and SES-adjusted models include all base model adjustments. They do not include race/ethnicity after stratification.
Test for adequacy of linear model was rejected, with 95% CI for spline term equal to (-0.166, -0.007); “low to moderate” term estimates the lead relation over lead values between 0 and 15 μg/g; “high vs. low/mod” term estimates the difference between the lead relation over lead values greater, and less than, 15 μg/g.