Table 3.
Quintile of phthalate and odds of preschool ADHD
| Model 1 crudea | Model 2adjusted for covariatesb | Model 3adjusted for covariates and correlated phthalate metabolitesc | |||
|---|---|---|---|---|---|
| Phthalate | Quintile | N casesd | OR (95% CI) | OR (95% CI) | OR (95% CI) |
| MEP | 1. <26.0 µg/L | 44 | ref. | ref. | |
| 2. 26.0–62.2 µg/L | 44 | 0.96 (0.59 to 1.56) | 0.91 (0.54 to 1.53) | ||
| 3. 62.2–148 µg/L | 57 | 1.28 (0.80 to 2.05) | 1.19 (0.72 to 1.95) | ||
| 4. 148–380 µg/L | 55 | 1.26 (0.79 to 2.01) | 1.24 (0.76 to 2.03) | ||
| 5. >380 µg/L | 53 | 1.18 (0.74 to 1.90) | 1.05 (0.63 to 1.75) | ||
| Linear modele | 253 | 1.06 (0.96 to 1.17) | 1.03 (0.93 to 1.15) | ||
| MiBPf | 1. <8.76 µg/L | 32 | ref. | ref. | ref. |
| 2. 8.76–13.2 µg/L | 41 | 1.30 (0.77 to 2.20) | 1.37 (0.79 to 2.39) | 1.61 (0.87 to 2.97) | |
| 3. 13.2–20.8 µg/L | 65 | 2.07 (1.26 to 3.39) | 1.88 (1.12 to 3.18) | 2.21 (1.19 to 4.10) | |
| 4. 20.8–38.9 µg/L | 75 | 2.32 (1.43 to 3.78) | 2.37 (1.41 to 3.99) | 2.77 (1.46 to 5.25) | |
| 5. >38.9 µg/L | 40 | 1.23 (0.73 to 2.09) | 1.19 (0.68 to 2.08) | 1.29 (0.65 to 2.57) | |
| Linear modele | 253 | 1.10 (0.93 to 1.30) | 1.08 (0.89 to 1.29) | 0.98 (0.78 to 1.24) | |
| MnBP | 1. <9.90 µg/L | 49 | ref. | ref. | ref. |
| 2. 9.90–14.6 µg/L | 41 | 0.83 (0.51 to 1.35) | 0.76 (0.45 to 1.27) | 0.54 (0.30 to 0.97) | |
| 3. 14.6–21.9 µg/L | 48 | 0.96 (0.60 to 1.55) | 0.92 (0.56 to 1.52) | 0.55 (0.29 to 1.03) | |
| 4. 21.9–34.0 µg/L | 55 | 1.17 (0.74 to 1.85) | 1.10 (0.67 to 1.80) | 0.59 (0.31 to 1.14) | |
| 5. >34.0 µg/L | 60 | 1.22 (0.77 to 1.93) | 1.15 (0.70 to 1.89) | 0.64 (0.32 to 1.30) | |
| Linear modele | 253 | 1.17 (0.97 to 1.41) | 1.18 (0.95 to 1.45) | 1.13 (0.84 to 1.52) | |
| MBzP | 1. <2.19 µg/L | 40 | ref. | ref. | ref. |
| 2. 2.19–3.46 µg/L | 40 | 1.06 (0.64 to 1.76) | 0.93 (0.54 to 1.59) | 0.93 (0.52 to 1.69) | |
| 3. 3.46–5.51 µg/L | 53 | 1.36 (0.84 to 2.22) | 1.27 (0.76 to 2.13) | 1.28 (0.71 to 2.30) | |
| 4. 5.51–9.60 µg/L | 54 | 1.40 (0.86 to 2.27) | 1.40 (0.83 to 2.33) | 1.41 (0.75 to 2.66) | |
| 5. >9.60 µg/L | 66 | 1.70 (1.06 to 2.72) | 1.39 (0.83 to 2.31) | 1.37 (0.71 to 2.64) | |
| Linear modele | 253 | 1.19 (1.01 to 1.40) | 1.13 (0.95 to 1.35) | 1.07 (0.85 to 1.35) | |
| ∑DEHP | 1. <0.16 µmol/L | 41 | ref. | ref. | ref. |
| 2. 0.16–0.21 µmol/L | 52 | 1.34 (0.83 to 2.17) | 1.26 (0.76 to 2.09) | 1.28 (0.76 to 2.15) | |
| 3. 0.21–0.27 µmol/L | 49 | 1.23 (0.75 to 2.01) | 1.23 (0.73 to 2.06) | 1.15 (0.68 to 1.97) | |
| 4. 0.27–0.38 µmol/L | 47 | 1.21 (0.74 to 1.97) | 1.23 (0.73 to 2.06) | 1.19 (0.70 to 2.03) | |
| 5. >0.38 µmol/L | 64 | 1.59 (0.99 to 2.54) | 1.58 (0.96 to 2.61) | 1.51 (0.89 to 2.56) | |
| Linear modelf | 253 | 1.17 (0.96 to 1.43) | 1.22 (0.99 to 1.52) | 1.18 (0.93 to 1.49) | |
| ∑DiNPf | 1. <0.012 µmol/L | 42 | ref. | ref. | ref. |
| 2. 0.012–0.016 µmol/L | 76 | 1.82 (1.15 to 2.88) | 2.07 (1.27 to 3.37) | 2.04 (1.25 to 3.33) | |
| 3. 0.016–0.020 µmol/L | 35 | 0.88 (0.53 to 1.47) | 0.89 (0.52 to 1.55) | 0.86 (0.50 to 1.50) | |
| 4. 0.020–0.027 µmol/L | 42 | 1.01 (0.61 to 1.66) | 1.13 (0.67 to 1.92) | 1.07 (0.62 to 1.82) | |
| 5. >0.027 µmol/L | 58 | 1.37 (0.85 to 2.20) | 1.70 (1.03 to 2.82) | 1.54 (0.91 to 2.61) | |
| Linear modele | 253 | 1.11 (0.89 to 1.39) | 1.18 (0.94 to 1.49) | 1.10 (0.85 to 1.42) |
aAdjusted for specific gravity, analytic batch.
bAdjusted for specific gravity, analytic batch, child sex and maternal age, education, parity, depression during pregnancy, and ADHD-like symptoms.
cAdjusted for specific gravity, analytic batch, child sex and maternal age, education, parity, depression during pregnancy, ADHD-like symptoms and additionally adjusted for correlated metabolites (a) MiBP, MnBP, and MBzP co-adjusted for one another; (b) ∑DEHP and ∑DiNP coadjusted for each other).
dNumber with no missing exposure or covariates in Model 2.
ePer 1 natural log-unit increase in biomarker.
fAssociated nonlinearly (Wald test P < 0.10) for MiBP and ∑DiNP when modeled using Model 2 adjustment set and restricted cubic splines with knots at 20th, 40th, 60th, and 80th percentiles.