TABLE 4.
Linear regression coefficients (95% CI) for post-bronchodilator lung function measures (z-scores) according to quartiles of intakes of preformed vitamin A and β-carotene equivalent, stratified by NCOR2 (nuclear receptor corepressor 2)# genotype (rs12708369)
| Quartiles of vitamin A intake | ptrend-value ¶ | pinteraction-value | ||||
| Quartile 1 | Quartile 2 | Quartile 3 | Quartile 4 | |||
| Preformed vitamin A | ||||||
| FEV1 | ||||||
| Genotype TT | 0.00 | −0.41 (−0.81– −0.02) | −0.27 (−0.65–0.10) | −0.55 (−1.03– −0.07) | 0.046 | |
| Genotype CT | 0.00 | −0.03 (−0.26–0.19) | 0.08 (−0.15–0.31) | 0.30 (0.04–0.56) | 0.01 | 0.01 |
| Genotype CC | 0.00 | 0.01 (−0.23–0.26) | 0.01 (−0.25–0.26) | 0.29 (−0.01–0.58) | 0.047 | 0.02 |
| FVC | ||||||
| Genotype TT | 0.00 | −0.23 (−0.61–0.15) | −0.29 (−0.66–0.07) | −0.63 (−1.09– −0.17) | 0.008 | |
| Genotype CT | 0.00 | −0.05 (−0.26–0.16) | 0.07 (−0.15–0.29) | 0.25 (0.01–0.50) | 0.02 | 0.003 |
| Genotype CC | 0.00 | 0.06 (−0.18–0.29) | 0.04 (−0.20–0.28) | 0.23 (−0.05–0.51) | 0.11 | 0.01 |
| FEV1/FVC | ||||||
| Genotype TT | 0.00 | −0.24 (−0.60–0.13) | 0.08 (−0.26–0.43) | 0.05 (−0.39–0.49) | 0.54 | |
| Genotype CT | 0.00 | 0.10 (−0.08–0.29) | 0.09 (−0.11–0.28) | 0.15 (−0.07–0.37) | 0.23 | 0.73 |
| Genotype CC | 0.00 | −0.04 (−0.26–0.17) | −0.00 (−0.23–0.22) | 0.01 (−0.24–0.27) | 0.84 | 0.66 |
| FEF25–75% | ||||||
| Genotype TT | 0.00 | −0.34 (−0.68–0.00) | −0.02 (−0.35–0.30) | −0.14 (−0.55–0.27) | 0.84 | |
| Genotype CT | 0.00 | 0.09 (−0.09–0.28) | 0.11 (−0.09–0.30) | 0.25 (0.03–0.47) | 0.03 | 0.37 |
| Genotype CC | 0.00 | −0.05 (−0.27–0.17) | −0.05 (−0.28–0.18) | 0.10 (−0.16–0.36) | 0.39 | 0.32 |
| β- carotene equivalent | ||||||
| FEV1 | ||||||
| Genotype TT | 0.00 | −0.44 (−0.82– −0.05) | −0.11 (−0.52–0.29) | −0.26 (−0.66–0.15) | 0.40 | |
| Genotype CT | 0.00 | 0.09 (−0.12–0.31) | 0.08 (−0.14–0.30) | −0.07 (−0.31–0.16) | 0.33 | 0.88 |
| Genotype CC | 0.00 | 0.15 (−0.09–0.38) | 0.27 (0.01–0.52) | 0.27 (0.02–0.53) | 0.06 | 0.23 |
| FVC | ||||||
| Genotype TT | 0.00 | −0.54 (−0.91– −0.17) | −0.16 (−0.55–0.23) | −0.15 (−0.54–0.24) | 0.89 | |
| Genotype CT | 0.00 | 0.09 (−0.11–0.30) | 0.10 (−0.11–0.31) | −0.04 (−0.27–0.18) | 0.46 | 0.61 |
| Genotype CC | 0.00 | 0.03 (−0.19–0.26) | 0.12 (−0.12–0.37) | 0.13 (−0.12–0.37) | 0.33 | 0.81 |
| FEV1/FVC | ||||||
| Genotype TT | 0.00 | 0.18 (−0.17–0.53) | 0.03 (−0.35–0.40) | −0.31 (−0.68–0.06) | 0.03 | |
| Genotype CT | 0.00 | 0.05 (−0.13–0.23) | −0.07 (−0.25–0.12) | −0.08 (−0.28–0.11) | 0.30 | 0.35 |
| Genotype CC | 0.00 | 0.14 (−0.06–0.35) | 0.20 (−0.02–0.42) | 0.15 (−0.08–0.37) | 0.35 | 0.07 |
| FEF25–75% | ||||||
| Genotype TT | 0.00 | −0.04 (−0.37–0.29) | −0.09 (−0.44–0.26) | −0.36 (−0.71– −0.01) | 0.03 | |
| Genotype CT | 0.00 | 0.00 (−0.18–0.19) | 0.02 (−0.16–0.21) | −0.03 (−0.23–0.17) | 0.73 | 0.25 |
| Genotype CC | 0.00 | 0.22 (0.01–0.44) | 0.28 (0.05–0.51) | 0.30 (0.07–0.53) | 0.03 | 0.009 |
FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; FEF25–75%: forced expiratory flow at 25–75% of FVC. Multivariable model: sex, total energy intake, maternal education, housing tenure at birth, financial difficulty during pregnancy, maternal ethnicity, maternal history of atopic disease, paternal history of atopic disease, maternal smoking, older sibling, younger sibling, supplement use and season when the food frequency questionnaire was completed. #: in TT, CT and TT groups, sample sizes were 380, 1227 and 948 for FEV1, and 397, 1287 and 985 for both FVC and FEF25–75%, respectively; ¶: linear trend was tested by treating the median values of quartiles as a continuous variable.