Table 3.
Associations between key early life sociodemographic and environmental factors and TL12 or ADHD symptoms at age two years.
| TL12 (T/S Ratio) | AP (T Score) | ADHP (T Score) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Factors | β (95% CI) * | p | β (95% CI) † | p | β (95% CI) ^ | p | β (95% CI) ^ | p | |
| Sociodemographic | |||||||||
| Maternal age at birth, years | 0.006 (−0.004, 0.02) | 0.24 | 0.007 (−0.003, 0.02) | 0.16 | −0.10 (−0.16, −0.03) | 0.003 | −0.10 (−0.16, −0.04) | 0.002 | |
| Paternal age at birth, years | 0.003 (−0.004, 0.01) | 0.41 | 0.003 (−0.005, 0.01) | 0.48 | −0.07 (−0.12, −0.03) | 0.002 | −0.05 (−0.10, −0.01) | 0.03 | |
| Maternal education: | |||||||||
| Year 11 or less | Reference | Reference | Reference | Reference | |||||
| Year 12 or equivalent | −0.09 (−0.17, −0.007) | 0.03 | −0.09 (−0.18, −0.004) | 0.04 | −1.08 (−2.97, 0.80) | 0.26 | −0.64 (−2.44, 1.16) | 0.48 | |
| Bachelor or Postgraduate degree | −0.04 (−0.09, 0.0007) | 0.05 | −0.04 (−0.09, 0.007) | 0.10 | −1.44 (−3.28, 0.40) | 0.13 | −1.05 (−2.79, 0.70) | 0.24 | |
| p-trend | 0.51 | 0.99 | 0.07 | 0.07 | |||||
| Paternal education: | |||||||||
| Year 11 or less | Reference | Reference | Reference | Reference | |||||
| Year 12 or equivalent | −0.08 (−0.16, 0.001) | 0.05 | −0.09 (−0.18, −0.001) | 0.05 | −1.19 (−2.64, 0.26) | 0.11 | −1.57 (−3.04, −0.10) | 0.04 | |
| Bachelor or Postgraduate degree | −0.04 (−0.08, 0.006) | 0.09 | −0.04 (−0.09, 0.01) | 0.15 | −1.46 (−2.91, −0.01) | 0.05 | −1.82 (−3.28, −0.36) | 0.01 | |
| p-trend | 0.34 | 0.75 | 0.04 | 0.04 | |||||
| Mean household income, AUD 10,000 | 0.01 (−0.02, 0.04) | 0.57 | 0.02 (−0.02, 0.06) | 0.28 | 0.32 (0.04, 0.61) | 0.03 | 0.35 (0.09, 0.61) | 0.007 | |
| Prenatal | |||||||||
| Perceived Stress Scale, score | 0.001 (−0.005, 0.007) | 0.75 | 0.004 (−0.003, 0.01) | 0.30 | 0.07 (0.02, 0.12) | 0.004 | 0.08 (0.03, 0.13) | 0.001 | |
| Edinburgh Depression Score: | |||||||||
| Low risk (<10) | Reference | Reference | Reference | Reference | |||||
| Moderate risk (10–12) | 0.02 (−0.16, 0.21) | 0.80 | −0.01 (−0.20, 0.18) | 0.91 | 0.74 (−0.55, 2.02) | 0.26 | 0.70 (−0.60, 2.00) | 0.29 | |
| High risk (>12) | 0.03 (−0.20, 0.27) | 0.78 | 0.06 (−0.19, 0.31) | 0.62 | 0.52 (−0.69, 1.73) | 0.40 | −0.28 (−1.18, 0.62) | 0.54 | |
| p-trend | 0.71 | 0.71 | 0.18 | 0.65 | |||||
| Antidepressant use | 0.03 (−0.20, 0.25) | 0.83 | 0.06 (−0.19, 0.31) | 0.62 | 1.82 (0.02, 3.63) | 0.05 | 1.56 (−0.23, 3.35) | 0.09 | |
| Tobacco smoking | 0.06 (−0.07, 0.19) | 0.38 | 0.03 (−0.01, 0.16) | 0.62 | 0.63 (−0.39, 1.65) | 0.23 | 0.67 (−0.32, 1.65) | 0.19 | |
| Maternal SHS exposure | −0.02 (−0.14, 0.10) | 0.71 | −0.02 (−0.15, 0.10) | 0.70 | 0.97 (−0.03, 1.97) | 0.06 | 0.93 (−0.04, 1.89) | 0.06 | |
| Recreational drug use a | −0.05 (−0.39, 0.29) | 0.76 | −0.10 (−0.38, 0.18) | 0.48 | −0.32 (−2.51, 1.87) | 0.78 | −0.86 (−1.46, −0.26) | 0.005 | |
| Perinatal | |||||||||
| Child’s sex: male | −0.09 (−0.17, −0.01) | 0.03 | −0.1 (−0.19, −0.009) | 0.03 | 0.42 (−0.13, 0.97) | 0.14 | 0.28 (−0.26, 0.82) | 0.31 | |
| Prematurity < 37 weeks | 0.03 (−0.19, 0.25) | 0.79 | 0.17 (−0.13, 0.46) | 0.27 | 2.05 (0.20, 3.90) | 0.03 | 1.07 (−0.38, 2.52) | 0.15 | |
| Apgar score at 5 min | −0.03 (−0.08, 0.006) | 0.10 | −0.04 (−0.09, −0.002) | 0.04 | −0.4 (−0.79, −0.007) | 0.05 | −0.57 (−1.02, −0.12) | 0.01 | |
| Postnatal | |||||||||
| Paternal tobacco smoking at six months | −0.05 (−0.19, 0.10) | 0.53 | −0.05 (−0.21, 0.12) | 0.58 | 0.62 (−0.24, 1.49) | 0.16 | 0.94 (0.007, 1.88) | 0.05 | |
| Child SHS exposure at one month | −0.29 (−0.53, −0.06) | 0.02 | −0.27 (−0.58, 0.04) | 0.08 | 3.34 (0.79, 5.90) | 0.01 | 2.27 (0.43, 4.12) | 0.02 | |
p values in italic indicates p-trend; Bold indicates estimates, 95% CI and corresponding p ≤ 0.05. * Adjusted for child’s sex, child’s age at the time of blood collection, time interval between blood collection and storage and cell type composition. † Additionally adjusted for telomere length at birth in the same model. ^ Adjusted for child’s sex and child’s age at the time of behavioral assessment. a Recreational drug use other than marijuana. Additional analysis: Associations between infant SHS exposure at one month and AP (β = 2.82; 95% CI (0.28, 5.36); p = 0.03) and ADHP (β = 1.61; 95% CI (-0.42, 3.63); p = 0.12), further adjusted for maternal perceived stress, maternal prenatal smoking, and maternal prenatal SHS exposure. AP—Attention Problems; ADHP—Attention Deficit/Hyperactivity Problems; TL12—telomere length at 12 months; SHS—secondhand smoke; T/S ratio—telomeric genomic DNA/β-globin single-copy gene.