Table 2.
Univariate predictors of asthma at 18 months, current asthma at 7 years, and ever asthma by hospitalization or prescription medication in the Danish National Birth Cohort
| Sociodemographic characteristics | Doctor-diagnosed asthma (18 months) N=21,293 OR (95 % CI) | P | Ever admitted asthma1 N=17,399 OR (95 % CI) | P | Ever prescribed asthma2 N=17,389 OR (95 % CI) | P | Current asthma3 (7 years) N=17,338 OR (95 % CI) |
|---|---|---|---|---|---|---|---|
| Maternal age (years) | |||||||
| ≤ 20 | 2.19 (1·42, 3·40) | 0·0004 | 2·82 (1·48, 5·36) | 0·0002 | 1·70 (1·39, 2·08) | <0·0001 | 2·10 (0·91, 4·86) |
| 21 – 39 | 1·00 | 1·00 | 1·00 | 1·00 | |||
| ≥ 40 | 0·58 (0·39, 0,86) | 0·01 | 0·15 (0·04, 0·61) | 0·01 | 0·68 (0·55, 0·83) | 0·0002 | 0·23 (0·06, 0·91) |
| Socioeconomic position | |||||||
| High level proficiencies | 1·00 | 1·00 | 1·00 | 1·00 | |||
| Medium level proficiencies | 1·19 (1·07, 1·32) | 0·001 | 1·19 (0·99, 1·43) | 0·07 | 1·15 (1·08, 1·21) | <0·0001 | 1·20 (0·96, 1·50) |
| Skilled | 1·37 (1·23, 1·52) | <0·0001 | 1·21 (0·99, 1·47) | 0·06 | 1·44 (1·36, 1·53) | <0·0001 | 1·16 (0·92, 1·47) |
| Unskilled | 1·58 (1·39, 1·80) | <0·0001 | 1·64 (1·30, 2·07) | <0·0001 | 1·61 (1·50, 1·73) | <0·0001 | 1·58 (1·20, 2·09) |
| Students | 0·96 (0·76, 1·19) | 0·68 | 1·34 (0·95, 1·88) | 0·09 | 1·15 (1·03, 1·28) | 0·01 | 0·93 (0·58, 1·49) |
| Unemployed | 1·86 (1·47, 2·36) | <0·0001 | 1·75 (1·18, 2·58) | 0·01 | 1·92 (1·70, 2·17) | <0·0001 | 1·98 (1·28, 3·08) |
| Prepregnancy BMI (kg/m2) | |||||||
| ≤ 18·5 | 0·83 (0·69, 1·01) | 0·07 | 1·18 (0·86, 1·62) | 0·30 | 1·02 (0·92, 1·13) | 0·72 | 0.49 (0·28, 0·85) |
| 18·6 – 24·9 | 1·00 | 1·00 | 1·00 | 1·00 | |||
| 25·0 – 29·9 | 1·13 (1·03, 1·24) | 0·01 | 1·23 (1·05, 1·45) | 0·001 | 1·21 (1·15, 1·27) | <0·0001 | 1·28 (1·06, 1·56) |
| 30·0 – 34·9 | 1·41 (1·22, 1·63) | <0·0001 | 1·51 (1·17, 1·96) | 0·002 | 1·37 (1·26, 1·50) | <0·0001 | 1·74 (1·30, 2·33) |
| ≥ 35·0 | 1·35 (1·06, 1·71) | 0·02 | 1·38 (0·87, 2·18) | 0·18 | 1·58 (1·38, 1·83) | <0·0001 | 1·08 (0·59, 1·99) |
| Physical activity | |||||||
| Yes | 1·00 | 1·00 | 1·00 | 1·00 | |||
| No | 1·17 (1·09, 1·26) | <0·0001 | 1·03 (0·90, 1v17) | 0·65 | 1·08 (1·03, 1·12) | 0·0004 | 1·11 (0·95, 1·30) |
| Smoking in pregnancy | |||||||
| Nonsmoker | 1·00 | 1·00 | 1·00 | 1·00 | |||
| Occasional smoker | 1·04 (0·93, 1·16) | 0·51 | 1·30 (1·08, 1·56) | 0·01 | 1·22 (1·16, 1·30) | <0·0001 | 1·17 (0·93, 1·46) |
| <15 cigarettes/day | 1·61 (1·44, 1·79) | <0·0001 | 1·68 (1·38, 2·04) | <0·0001 | 1·71 (1·61, 1·82) | <0·0001 | 1·34 (1·05, 1·71) |
| ≥15 cigarettes/day | 2·00 (1·57, 2·56) | <0·0001 | 1·73 (1·08, 1·56) | 0·02 | 2·01 (1·75, 2·30) | <0·0001 | 1·54 (0·87, 2·72) |
| Parity | |||||||
| Nullipara | 1·00 | 1·00 | 1·00 | 1·00 | |||
| Multipara | 1·22 (1·13, 1·31) | <0·0001 | 1·06 (0·93, 1·20) | 0·33 | 0·87 (0·83, 0·90) | <0·0001 | 1·11 (0·95, 1·29) |
| Breast-feeding duration | |||||||
| No breastfeeding | 1·00 | 1·00 | 1·00 | 1·00 | |||
| 0-1 months | 1·08 (0·78, 1·49) | 0·64 | 0·93 (0·53, 1·64) | 0·80 | 0·88 (0·74, 1·04) | 0·14 | 0·961 (0·33, 1·12) |
| 2-3 months | 1·16 (0·84, 1·59) | 0·37 | 1·17 (0·68, 2·02) | 0·58 | 0·88 (0·74, 1·04) | 0·13 | 0·72 (0·40, 1·30) |
| 4-6 months | 0·96 (0·70, 1·30) | 0·79 | 0·72 (0·42, 1·23) | 0·23 | 0·71 (0·61, 0·84) | <0·0001 | 0·46 (0·26, 0·81) |
| 7-9 months | 0·70 (0·52, 0·95) | 0·02 | 0·61 (0·36, 1·04) | 0·07 | 0·55 (0·47, 0·64) | <0·0001 | 0·42 (0·24, 0·73) |
| ≥10 months | 0·61 (0·45, 0·83) | 0·001 | 0·62 (0·37, 1·06) | <0·08 | 0·49 (0·42, 0·57) | <0·0001 | 0·52 (0·30, 0·89) |
| Maternal asthma | |||||||
| Yes | 1·86 (1·66, 2·08) | <0·0001 | 2·01 (1·67, 2·42) | <0·0001 | 1·76 (1·65, 1·88) | <0·0001 | 2·77 (2·27, 3·39) |
| No | 1·00 | 1·00 | 1·00 | 1·00 | |||
| Maternal allergies | |||||||
| Yes | 1·27 (1·18, 1·37) | <0·0001 | 1·36 (1·19, 1·55) | <0·0001 | 1·21 (1·16, 1·26) | <0·0001 | 1·79 (1·53, 2·09) |
| No | 1·00 | 1·00 | 1·00 | 1·00 | |||
| Paternal asthma | |||||||
| Yes | 1·68 (1·49, 1·89) | <0·0001 | 2·31 (1·92, 2·77) | <0·0001 | 1·55 (1·44, 1·66) | <0·0001 | 2·89 (2·35, 3·54) |
| No | 1·00 | 1·00 | 1·00 | 1·00 | |||
| Paternal allergies | |||||||
| Yes | 1·19 (1·09, 1·29) | <0·0001 | 1·41 (1·22, 1·62) | <0·0001 | 1·09 (1·04, 1·14) | 0·0003 | 1·53 (1·30, 1·81) |
| No | 1·00 | 1·00 | 1·00 | 1·00 | |||
| Child sex | |||||||
| Male | 1·60 (1·49, 1·72) | <0·0001 | 1·83 (1·60, 2·09) | <0·0001 | 1·37 (1·32, 1·42) | <0·0001 | 1·96 (1·67, 2·30) |
| Female | 1·00 | 1·00 | 1·00 | 1·00 |
1
Ever admitted asthma: first registered asthma diagnosis in the Danish National Patient Registry.
2
Ever prescribed asthma: >=2 asthma prescription in the Register of Medicinal Product Statistics except for beta-2-agonists as liquid, inhaled beta-2-agonists only once, or inhaled steroid only once.
3
Current asthma: self-reported doctor diagnosis of asthma plus wheeze in the past 12 months.