Table 3.
Logistic regression
| Adjusted for sex | Adjusted for sex and tryptophan | |||||
|---|---|---|---|---|---|---|
| B | p value | Odds ratio (95 % confidence interval) | B | p value | Odds ratio (95 % confidence interval) | |
| Tryptophan | −0.50 | 0.002** | 0.61 (0.45–0.83) | |||
| Kynurenine | −0.23 | 0.14 | 0.80 (0.59–1.08) | −0.04 | 0.80 | 0.96 (0.69–1.34) |
| Kyn/Trp-ratio (KTR) | 0.12 | 0.45 | 1.12 (0.83–1.51) | −0.11 | 0.53 | 0.90 (0.64–1.25) |
| 3-hydroxykynurenine (HK) | −0.01 | 0.70 | 0.94 (0.70–1.27) | 0.01 | 0.94 | 1.01 (0.74–1.38) |
| Kynurenic acid (KA) | −0.32 | 0.04* | 0.73 (0.53–0.99) | −0.21 | 0.21 | 0.81 (0.59–1.12) |
| Xanthurenic acid (XA) | −0.43 | 0.006** | 0.65 (0.48–0.89) | −0.30 | 0.07 | 0.74 (0.54–1.03) |
| Anthranilic acid (AA) | −0.01 | 0.97 | 0.99 (0.74–1.34) | 0.04 | 0.79 | 1.04 (0.77–1.42) |
| 3-hydroxyanthranilic acid (HAA) | −0.47 | 0.003** | 0.63 (0.46–0.85) | −0.38 | 0.02* | 0.69 (0.50–0.94) |
| Quinolinic acid (QA) | −0.02 | 0.90 | 0.98 (0.73–1.32) | 0.04 | 0.82 | 1.04 (0.76–1.41) |
| Riboflavin (vitamin B2) | −0.39 | 0.01* | 0.68 (0.50–0.92) | −0.34 | 0.03* | 0.71 (0.52–0.97) |
| Total vitamin B6 | −0.17 | 0.26 | 0.84 (0.62–1.14) | −0.09 | 0.55 | 0.91 (0.67–1.24) |
| Cotinine | 1.97 | <0.001*** | 7.17 (4.37–12.58) | 1.94 | <0.001*** | 6.96 (4.22–12.25) |
Odds ratio of ADHD per tertile of variable. Cotinine is divided into three categories corresponding to the serum level in non-smokers, smokers and heavy smokers. All participants included: N = 264. Significance <0.001: ‘***’, <0.01: ‘**’, <0.05: ‘*’