Table 2.
Associations of 25‐hydroxyvitamin D concentrations in mid‐gestation with respiratory and allergy outcomes at age 10 y
|
FEV1 Z‐score change (95% CI) n = 4199 |
FVC Z‐score change (95% CI) n = 4199 |
FEV1/FVC Z‐score change (95% CI) n = 4199 |
FEF75 Z‐score change (95% CI) n = 4199 |
Current asthma OR (95% CI) n = 3950 |
Inhalant allergic sensitization OR (95% CI) n = 3439 |
Inhalant allergy OR (95% CI) n = 2778 |
|
|---|---|---|---|---|---|---|---|
| Model 1: Main model | |||||||
| 25‐hydroxyvitamin D per 10 nmol/L (n = 4507) | 0.00 (−0.01, 0.02) | 0.02 (0.00, 0.03) | −0.02 (−0.03, −0.01) | −0.01 (−0.03, −0.00) | 1.04 (0.98, 1.10) | 1.01 (0.98, 1.04) | 1.07 (1.02, 1.12) |
| Clinical cut‐offs | |||||||
| Severely deficient (n = 905) | −0.01 (−0.11, 0.09) | −0.07 (−0.17, 0.02) | 0.10 (−0.00, 0.20) | 0.09 (−0.01, 0.18) | 0.98 (0.62, 1.54) | 1.02 (0.79, 1.31) | 0.70 (0.47, 1.05) |
| Deficient (n = 1178) | −0.03 (−0.11, 0.04) | −0.05 (−0.12, 0.02) | 0.02 (−0.06, 0.09) | 0.03 (−0.04, 0.10) | 0.94 (0.66, 1.35) | 0.89 (0.73, 1.07) | 0.90 (0.61, 1.33) |
| Sufficient (n = 2424) | Reference | Reference | Reference | Reference | Reference | Reference | Reference |
| Model 2: Child 25‐hydroxyvitamin D model | |||||||
| 25‐hydroxyvitamin D per 10 nmol/L (n = 2580) | −0.00 (−0.02, 0.01) | 0.01 (−0.00, 0.03) | −0.02 (−0.03, −0.00) | −0.02 (−0.03, −0.00) | 1.07 (0.99, 1.15) | 1.01 (0.97, 1.05) | 1.04 (0.98, 1.12) |
| Clinical cut‐offs | |||||||
| Severely deficient (n = 508) | 0.03 (−0.09, 0.16) | −0.04 (−0.16, 0.08) | 0.10 (−0.03, 0.23) | 0.08 (−0.04, 0.20) | 0.95 (0.52, 1.75) | 0.95 (0.69, 1.32) | 0.93 (0.54, 1.58) |
| Deficient (n = 678) | 0.01 (−0.09, 0.10) | −0.02 (−0.11, 0.07) | 0.03 (−0.07, 0.12) | 0.05 (−0.04, 0.14) | 0.78 (0.48, 1.27) | 0.91 (0.71, 1.16) | 0.87 (0.58, 1.31) |
| Sufficient (n = 1394) | Reference | Reference | Reference | Reference | Reference | Reference | Reference |
Values are change in Z‐scores or odds ratios (OR) with 95% confidence interval (95% CI), derived from linear or logistic regression models, respectively. Bold indicates P‐value < 0.05. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), forced expiratory flow after exhaling 75% of FVC (FEF75). Concentrations of 25‐hydroxyvitamin D are categorized as “severely deficient” (<25.0 nmol/L [<10.0 mg/L]), “deficient” (25.0 to <50.0 nmol/L [10.0 to <20.0 mg/L]), “sufficient” (≥50.0 nmol/L [≥20.0 mg/L]). Model 1 (main model) was adjusted for the confounders maternal age, BMI at enrolment, educational level, history of asthma or atopy, psychiatric symptoms (GSI), parity, smoking during pregnancy, pet keeping, damp patches or mould in the house, folate concentration and season of blood sampling, and child's sex, gestational age at birth, birthweight, ethnic background, breastfeeding and day care attendance. Model 2 (Child 25‐hydroxyvitamin D model) comprised the main model and was additionally adjusted for season‐adjusted 25‐hydroxyvitamin D concentrations at the age of 6 y.