Table 2.
Associations 1 between total vitamin D intake in mid-pregnancy and child asthma in the Danish National Birth Cohort
|
Quintile of intake |
|
Cases/N |
Asthma (18 months) N = 33,425/29,161
2
/28,421
3
|
P for trend
4
|
Cases/N |
Current asthma (7 years - ISAAC) N = 28,687/25,025
2
/24,382
3
|
P for trend
4
|
Cases/N |
Ever admitted asthma N = 28,767/25,095
2
/24,452
3
|
P for trend
4
|
Cases/N |
Ever prescribed asthma N = 28,758/25,094
2
/25,452
3
|
P for trend
4
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| RR (95% CI) | RR (95% CI) | RR (95% CI) | RR (95% CI) | ||||||||||
| Continuous |
Crude |
5,635/33,425 (17%) |
1.00 (0.99, 1.00) |
0.90 |
1,122/28,687 (4%) |
1.00 (0.99, 1.01) |
0.73 |
1,654/28,767 (6%) |
1.00 (0.99, 1.01) |
0.88 |
8,906/28,758 (31%) |
1.00 (1.00, 1.01) |
0.04 |
| Adjusted2 |
|
1.00 (1.00, 1.01) |
0.59 |
|
1.00 (0.99, 1.01) |
0.88 |
|
1.00 (0.99, 1.01) |
0.45 |
|
1.01 (1.00, 1.01) |
0.15 |
|
| Adjusted3 |
|
1.00 (0.99, 1.01) |
0.91 |
|
0.99 (0.97, 1.00) |
0.09 |
|
0.99 (0.97, 1.00) |
0.08 |
|
1.00 (0.99, 1.00) |
0.30 |
|
| 1 |
Crude |
1,123/6,627 (17%) |
1.00 (ref.) |
0.54 |
219/5,728 (4%) |
1.00 (ref.) |
0.67 |
344/5,743 (6%) |
1.00 (ref.) |
0.92 |
1,724/5,741 (30%) |
1.00 (ref.) |
0.05 |
| Adjusted2 |
|
|
0.85 |
|
|
0.70 |
|
|
0.41 |
|
|
0.21 |
|
| Adjusted3 |
|
|
0.40 |
|
|
0.06 |
|
|
0.06 |
|
|
0.36 |
|
| 2 |
Crude |
1,137/6,836 (17%) |
0.98 (0.91, 1.06) |
|
218/5,936 (4%) |
0.96 (0.80, 1.15) |
|
318/5,953 (5%) |
0.89 (0.77, 1.03) |
|
1,811/5,953 (30%) |
1.01 (0.96, 1.07) |
|
| Adjusted2 |
|
1.01 (0.93, 1.09) |
|
|
0.98 (0.81, 1.19) |
|
|
0.92 (0.79, 1.08) |
|
|
1.04 (0.98, 1.10) |
|
|
| Adjusted3 |
|
1.00 (0.91, 1.10) |
|
|
0.84 (0.67, 1.05) |
|
|
0.88 (0.73, 1.06) |
|
|
0.99 (0.93, 1.06) |
|
|
| 3 |
Crude |
1,170/6,725 (17%) |
1.03 (0.95, 1.11) |
|
231/5,710 (4%) |
1.06 (0.88, 1.27) |
|
341/5,725 (6%) |
0.99 (0.86, 1.15) |
|
1,798/5,721 (31%) |
1.05 (0.99, 1.11) |
|
| Adjusted2 |
|
1.04 (0.96, 1.12) |
|
|
1.02 (0.84, 1.24) |
|
|
0.96 (0.82, 1.12) |
|
|
1.04 (0.98, 1.10) |
|
|
| Adjusted3 |
|
1.00 (0.91, 1.11) |
|
|
0.87 (0.69, 1.10) |
|
|
0.90 (0.74, 1.09) |
|
|
0.96 (0.90, 1.03) |
|
|
| 4 |
Crude |
1,146/6,714 (17%) |
1.01 (0.93, 1.09) |
|
247/5,702 (4%) |
1.13 (0.95, 1.35) |
|
331/5,714 (6%) |
0.97 (0.84, 1.12) |
|
1,810/5,712 (32%) |
1.06 (1.00, 1.11) |
|
| Adjusted2 |
|
1.01 (0.93, 1.09) |
|
|
1.08 (0.90, 1.31) |
|
|
0.92 (0.79, 1.08) |
|
|
1.04 (0.98, 1.10) |
|
|
| Adjusted3 |
|
0.96 (0.86, 1.07) |
|
|
0.91 (0.71, 1.17) |
|
|
0.80 (0.65, 0.99) |
|
|
0.95 (0.88, 1.03) |
|
|
| 5 |
Crude |
1,059/6,523 (16%) |
0.96 (0.89, 1.03) |
|
207/5,611 (4%) |
0.96 (0.80, 1.16) |
|
320/5,632 (6%) |
0.95 (0.82, 1.10) |
|
1,763/5,631 (31%) |
1.04 (0.99, 1.10) |
|
| Adjusted2 |
|
0.99 (0.91, 1.07) |
|
|
0.91 (0.75, 1.11) |
|
|
0.92 (0.79, 1.08) |
|
|
1.04 (0.98, 1.11) |
|
|
| Adjusted3 | 0.96 (0.86, 1.07) | 0.74 (0.56, 0.96) | 0.80 (0.64, 1.00) | 0.97 (0.89, 1.05) |
1Analyzed using log-binomial models.
2Adjusted for maternal age, socio-economic status, parity, prepregnancy BMI, smoking during pregnancy, partner’s smoking during pregnancy, solarium use during pregnancy, breastfeeding duration, child sex, maternal history of asthma, maternal history of allergies, paternal history of asthma, paternal history of allergies, season of last menstrual period, and energy (in quintiles).
3Adjusted as in 2 plus fruit and vegetable intake, alcohol consumption, and intake of total EPA + DPA + DHA, vitamins A, C, and E, folate, calcium, selenium, and zinc (all in quintiles).
4Median values for each quintile entered as a continuous variable into the model. For continuous exposure the P-value reflects the P-value of the effect estimate.
ISAAC: International Study of Asthma and Allergies in Childhood.
EPA: Eicosapentaenoic acid.
DPA: Docosapentaenoic acid.
DHA: Docosahexaenoic acid