Table 3.
Regression coefficients from multiple regression models (n = 278) with main effects and tests for interaction by racea
| Marker/test | Inflammatory marker: test for trendb (p-value) | Caucasians vs. AAsc (referent) (p-value) | Marker quartile 2 vs 1d | Marker quartile 3 vs 1 | Marker quartile 4 vs 1 | Interaction term for racee (p-value) |
|---|---|---|---|---|---|---|
| IL8/Identify Odd Pattern | 2.2 ± 3.5 (0.53) | −453.5 ± 72.4 (<0.001) | −70.6 ± 78.0 | 109.3 ± 79.8 | 60.2 ± 78.5 | (0.14) |
| IL8/Recall a Pattern | −.0 ± 2.4 (1.00) | −265.3 ± 49.4 (<0.001) | −68.9 ± 53.4 | 34.2 ± 54.6 | 7.2 ± 53.7 | (.006) |
| IL8/Digit Symbol Substitution | 3.9 ± 2.6 (0.13) | −187.6 ± 52.6 (<0.001) | −50.7 ± 57.0 | 9.1 ± 58.3 | 75.9 ± 57.4 | (.014) |
| IL8/Digit Span Forward | −1.0 ± 1.2 (0.24) | −63.8 ± 24.2 (<0.01) | −13.6 ± 26.2 | 14.2 ± 26.8 | −30.7 ± 26.4 | (0.16) |
| IL8/Digit Span Backward | 5.5 ± 3.7 (0.14) | −306.0 ± 75.6 (<0.001) | 48.5 ± 82.3 | 89.8 ± 84.2 | 93.0 ± 82.8 | (0.10) |
| IL6/Identify Odd Pattern | 4.3 ± 14.0 (0.76) | −447.5 ± 72.3 (<0.001) | 12.2 ± 79.2 | −9.8 ± 80.6 | 88.3 ± 80.6 | (0.43) |
| IL6/Recall a Pattern | −4.0 ± 9.4 (0.66) | −267.0 ± 49.3 (<0.001) | −3.7 ± 54.1 | 37.0 ± 55.1 | 35.3 ± 55.0 | (0.66) |
| IL6/Digit Symbol Substitution | 8.8 ± 10.0 (0.38) | −176.3 ± 52.7 (<0.001) | −17.1 ± 57.6 | −15.8 ± 58.6 | 85.1 ± 58.6 | (.51) |
| IL6/Digit Span Forward | 1.8 ± 4.6 (0.70) | −65.7 ± 24.2 (<0.01) | −5.6 ± 26.5 | 4.6 ± 26.9 | 34.2 ± 26.9 | (0.97) |
| IL6/Digit Span Backward | 11.0 ± 14.0 (0.44) | −290.9 ± 75.7 (<0.001) | −18.1 ± 81.5 | −31.1 ± 84.0 | 133.7 ± 83.9 | (0.48) |
| CRP/identify Odd Pattern | −1.0 ± 65.0 (0.99) | −448.9 ± 72.4 (<0.001) | −202.6 ± 90.8 | 4.8 ± 74.7 | 61.5 ± 73.5 | (0.76) |
| CRP/Recall a Pattern | 14.0 ± 44.0 (0.76) | −263.8 ± 49.3 (<0.001) | −111.9 ± 62.0 | −20.2 ± 51.0 | 49.0 ± 50.2 | (.70) |
| CRP/Digit Symbol Substitution | −43.0 ± 48.0 (0.37) | −180.5 ± 52.7 (<0.001) | −58.1 ± 67.0 | −19.6 ± 55.1 | −33.7 ± 54.2 | (.63) |
| CRP/Digit Span Forward | −22.0 ± 21.0 (0.30) | −70.1 ± 23.4 (0.01) | −54.3 ± 29.7 | −12.8 ± 24.4 | −2.9 ± 24.0 | (0.91) |
| CRP/Digit Span Backward | 31.0 ± 68.0 (0.65) | −295.3 ± 75.7 (<0.001) | −77.7 ± 96.0 | 53.5 ± 79.0 | 47.8 ± 77.7 | (0.13) |
| TNF-α/Identify Odd Pattern | −3.0 ± 3.7 (0.37) | −445.5 ± 72.1 (<0.001) | 36.4 ± 78.2 | 79.5 ± 79.6 | −81.5 ± 78.7 | (0.75) |
| TNF-α/Recall a Pattern | −3.0 ± 2.5 (0.30) | −262.3 ± 49.2 (<0.001) | −10.7 ± 53.5 | −20.1 ± 51.0 | −85.1 ± 53.8 | (0.41) |
| TNF-α/Digit Symbol Substitution | −2.0 ± 2.7 (0.36) | −177.1 ± 52.6 (<0.001) | −5.4 ± 57.2 | 48.5 ± 58.2 | −58.1 ± 57.6 | 0.43 |
| TNF-α/Digit Span Forward | −2.0 ± 2.7 (0.36) | −65.4 ± 24.1 (0.01) | −3.9 ± 26.4 | −19.0 ± 26.8 | −13.8 ± 26.5 | (0.90) |
| TNF-α/Digit Span Backward | −2.0 ± 3.9 (0.54) | −292.7 ± 75.6 (p < 0.001) | −1.2 ± 82.6 | 49.5 ± 84.0 | −7.5 ± 83.0 | (0.32) |
All models adjust for age, gender, and education. Columns 2–6 are results for models with main effects only (no interaction term in model)
A negative coefficient indicates that higher levels of the marker are associated with shorter (faster) reaction times, measured in milliseconds. No categorical variables (columns 4–6) included in this model.
A negative coefficient indicates that reaction times, measured in milliseconds, are faster for Caucasians than African Americans on the cognitive measures.
Cutpoints for quartiles determined by dividing the population into four equal-sized groups. No continuous variable for inflammatory markers included in this model using categories.
The interaction term tests whether Caucasians and African Americans differ in the relationship between marker and cognitive test. The interaction term was added to the main effects model.