TABLE 5.
Interactions between circulating blood cadmium concentrations and circulating serum concentrations of carotenoids and percentage difference in telomere length (telomere-to–single-copy gene ratio) (NHANES 2001–2002 only)1
| Low |
High |
||||||
| n | % Difference (95% CI) | P-trend3 | n | % Difference (95% CI) | P-trend3 | P-interaction2 | |
| Serum α-carotene | |||||||
| Blood cadmium, μg/L | 0.27 | 0.59 | 0.09 | ||||
| ≤0.2 (quartile 1) | 220 | Reference | 916 | Reference | |||
| >0.2 to ≤0.4 (quartile 2) | 200 | −5.79 (−10.5, −0.79) | 989 | −0.56 (−3.16, 2.10) | |||
| >0.4 to ≤0.6 (quartile 3) | 168 | −7.60 (−13.0, −1.83) | 613 | −0.46 (−2.88, 2.02) | |||
| >0.6 (quartile 4) | 361 | −2.80 (−8.16, 2.48) | 542 | 0.16 (−3.18, 2.11) | |||
| Continuous (per 1 μg/L) | 949 | −1.66 (−4.16, 0.90) | 0.23 | 3060 | −0.17 (−1.27, 0.80) | 0.63 | 0.62 |
| Serum β-carotene | |||||||
| Blood cadmium, μg/L | 0.50 | 0.59 | 0.25 | ||||
| ≤0.2 (quartile 1) | 239 | Reference | 897 | Reference | |||
| >0.2 to ≤0.4 (quartile 2) | 231 | −4.33 (−9.05, 0.64) | 958 | −0.44 (−3.30, 2.52) | |||
| >0.4 to ≤0.6 (quartile 3) | 157 | −5.93 (−11.7, 0.23) | 624 | −0.88 (−3.55, 1.86) | |||
| >0.6 (quartile 4) | 320 | −2.17 (−9.05, 5.23) | 583 | −0.62 (−2.97, 1.79) | |||
| Continuous (per 1 μg/L) | 947 | −1.25 (−4.78, 2.40) | 0.47 | 3062 | −0.33 (−1.64, 0.97) | 0.59 | 0.52 |
| Serum β-cryptoxanthin | |||||||
| Blood cadmium, μg/L | 0.21 | 0.54 | 0.99 | ||||
| ≤0.2 (quartile 1) | 203 | Reference | 926 | Reference | |||
| >0.2 to ≤0.4 (quartile 2) | 229 | −1.97 (−5.33, 1.52) | 955 | −1.40 (−3.83, 1.08) | |||
| >0.4 to ≤0.6 (quartile 3) | 171 | −3.41 (−7.59, 0.96) | 604 | −2.03 (−5.31, 1.36) | |||
| >0.6 (quartile 4) | 334 | −2.25 (−6.40, 2.08) | 568 | −0.08 (−2.75, 2.26) | |||
| Continuous (per 1 μg/L) | 937 | −0.90 (−3.49, 1.76) | 0.47 | 3053 | −0.58 (−2.10, 0.83) | 0.39 | 0.46 |
| Serum lutein + zeaxanthin | |||||||
| Blood cadmium, μg/L | 0.56 | 0.38 | 0.55 | ||||
| ≤0.2 (quartile 1) | 202 | Reference | 932 | Reference | |||
| >0.2 to ≤0.4 (quartile 2) | 200 | −5.43 (−9.87, –0.78) | 986 | −0.44 (−3.46, 2.69) | |||
| >0.4 to ≤0.6 (quartile 3) | 129 | −2.62 (−12.6, −0.28) | 652 | −1.58 (−4.10, 1.01) | |||
| >0.6 (quartile 4) | 249 | −1.71 (−6.50, 3.32) | 656 | −0.45 (−3.09, 2.26) | |||
| Continuous (per 1 μg/L) | 780 | −0.82 (−3.35, 1.78) | 0.51 | 3226 | −0.65 (−2.10, 0.83) | 0.36 | 0.88 |
| Serum lycopene | |||||||
| Blood cadmium, μg/L | 0.19 | 0.70 | 0.30 | ||||
| ≤0.2 (quartile 1) | 269 | Reference | 865 | Reference | |||
| >0.2 to ≤0.4 (quartile 2) | 317 | 1.83 (−6,10, 2.63) | 869 | −1.39 (−4.20, 1.50) | |||
| >0.4 to ≤0.6 (quartile 3) | 270 | −2.12 (−7.01, 3.03) | 511 | −2.23 (−4.86, 0.47) | |||
| >0.6 (quartile 4) | 326 | −3.55 (−8.37, 1.53) | 579 | −0.45 (−3.53, 2.72) | |||
| Continuous (per 1 μg/L) | 1182 | −2.30 (−4.75, 0.21) | 0.07 | 2824 | −0.01 (−1.45, 1.45) | 0.99 | 0.23 |
| Combined serum carotenoids | |||||||
| Blood cadmium, μg/L | 0.55 | 0.36 | 0.94 | ||||
| ≤0.2 (quartile 1) | 214 | Reference | 915 | Reference | |||
| >0.2 to ≤0.4 (quartile 2) | 217 | −3.03 (−7.20, 1.32) | 967 | −1.19 (−3.89, 1.59) | |||
| >0.4 to ≤0.6 (quartile 3) | 170 | −2.77 (−7.67, 2.38) | 605 | −2.30 (−3.63, 1.06) | |||
| >0.6 (quartile 4) | 322 | −1.58 (−6.91, 4.06) | 578 | −0.51 (−3.60, 1.93) | |||
| Continuous (per 1 μg/L) | 923 | −1.52 (−4.00, 1.03) | 0.22 | 3065 | −0.37 (−1.85, 1.13) | 0.66 | 0.84 |
Low: ≤25th percentile; high: >25th percentile. Serum α-carotene—low: ≤1.3 μg/dL, high: >1.3 μg/dL; serum β-carotene—low: ≤7.69 μg/dL, high: >7.69 μg/dL; serum β-cryptoxanthin—low: ≤4.8 μg/dL, high: >4.8 μg/dL; serum lutein + zeaxanthin—low: ≤9.4 μg/dL, high: >9.4 μg/dL; serum lycopene—low: ≤15.5 μg/dL, high: >15.5 μg/dL; combined serum carotenoids—low: ≤46.6 μg/dL, high: >46.6 μg/dL.
Model also included nutrient and nutrient-cadmium interaction terms.
Linear regression models were adjusted for age, age squared, BMI, serum cotinine, education level, sex, and race/ethnicity and evaluated by circulating nutrient category (low or high). Nutrient categories were evaluated as a population domain.