Table 1 Hazard ratios for childhood diseases per interquartile range unit increase in exposures at birth*
Factors | Asthma | Allergic Rhinitis | Eczema | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
HR | 95% CI | HR | 95% CI | HR | 95% CI | |||||||||||||
Exposure | ||||||||||||||||||
Reactive Oxygen Species | 1.11 | ( | 1.02 | - | 1.21 | ) | 0.96 | ( | 0.88 | - | 1.04 | ) | 1.03 | ( | 0.98 | - | 1.09 | ) |
Iron | 1.06 | ( | 0.99 | - | 1.14 | ) | 1.06 | ( | 0.99 | - | 1.14 | ) | 1.02 | ( | 0.98 | - | 1.06 | ) |
Copper | 1.04 | ( | 0.96 | - | 1.14 | ) | 0.95 | ( | 0.88 | - | 1.03 | ) | 1.01 | ( | 0.96 | - | 1.06 | ) |
Child factors | ||||||||||||||||||
Age group | ||||||||||||||||||
7 years | 0.95 | ( | 0.76 | - | 1.18 | ) | 1.03 | ( | 0.86 | - | 1.24 | ) | 1.00 | ( | 0.88 | - | 1.15 | ) |
8–9 years | 1.11 | ( | 0.78 | - | 1.57 | ) | 0.82 | ( | 0.59 | - | 1.15 | ) | 1.15 | ( | 0.91 | - | 1.44 | ) |
Male sex | 1.62 | ( | 1.31 | - | 2.00 | ) | 1.28 | ( | 1.07 | - | 1.53 | ) | 1.15 | ( | 1.01 | - | 1.31 | ) |
Low birthweight (< 2500 g) | 1.30 | ( | 0.82 | - | 2.04 | ) | 0.93 | ( | 0.60 | - | 1.43 | ) | 1.07 | ( | 0.79 | - | 1.45 | ) |
Breastfeeding | 0.64 | ( | 0.45 | - | 0.89 | ) | 0.81 | ( | 0.60 | - | 1.10 | ) | 1.00 | ( | 0.79 | - | 1.27 | ) |
Enrollment in childcare | 1.04 | ( | 0.82 | - | 1.32 | ) | 0.91 | ( | 0.75 | - | 1.11 | ) | 1.14 | ( | 0.98 | - | 1.32 | ) |
Child born within three weeks of due date | 1.27 | ( | 0.82 | - | 1.94 | ) | 0.93 | ( | 0.62 | - | 1.40 | ) | 0.94 | ( | 0.71 | - | 1.24 | ) |
Parental/demographic factors | ||||||||||||||||||
Parental history of asthma | 1.37 | ( | 1.05 | - | 1.80 | ) | 1.29 | ( | 1.02 | - | 1.63 | ) | 0.98 | ( | 0.82 | - | 1.16 | ) |
Parental history atopy | 1.28 | ( | 0.99 | - | 1.66 | ) | 1.15 | ( | 0.93 | - | 1.42 | ) | 1.11 | ( | 0.95 | - | 1.29 | ) |
Parental education level | ||||||||||||||||||
Less than or some college or university | 1.31 | ( | 0.89 | - | 1.92 | ) | 1.47 | ( | 1.07 | - | 2.01 | ) | 1.60 | ( | 1.27 | - | 2.01 | ) |
College diploma | 1.33 | ( | 0.92 | - | 1.93 | ) | 1.37 | ( | 1.01 | - | 1.86 | ) | 1.42 | ( | 1.14 | - | 1.77 | ) |
University degree | 1.39 | ( | 0.99 | - | 1.94 | ) | 1.14 | ( | 0.87 | - | 1.50 | ) | 1.29 | ( | 1.06 | - | 1.56 | ) |
Income adequacy | ||||||||||||||||||
Lowest income adequacy | 1.44 | ( | 0.94 | - | 2.20 | ) | 1.24 | ( | 0.86 | 1.78 | ) | 1.46 | ( | 1.12 | - | 1.90 | ) | |
Lower middle income adequacy | 1.52 | ( | 1.07 | - | 2.16 | ) | 1.56 | ( | 1.18 | - | 2.08 | ) | 1.07 | ( | 0.85 | - | 1.35 | ) |
Upper middle income adequacy | 1.52 | ( | 1.15 | - | 2.00 | ) | 0.89 | ( | 0.69 | - | 1.15 | ) | 1.13 | ( | 0.94 | - | 1.34 | ) |
Home environmental factors | ||||||||||||||||||
Crowding (No. of people in household) | ||||||||||||||||||
4 people in household | 1.22 | ( | 0.88 | - | 1.70 | ) | 0.86 | ( | 0.66 | - | 1.12 | ) | 1.03 | ( | 0.85 | - | 1.26 | ) |
≥ 5 people in household | 1.16 | ( | 0.83 | - | 1.64 | ) | 0.78 | ( | 0.59 | - | 1.03 | ) | 0.93 | ( | 0.75 | - | 1.15 | ) |
Use of gas to cook or heat | 0.98 | ( | 0.77 | - | 1.26 | ) | 0.82 | ( | 0.67 | - | 1.01 | ) | 0.99 | ( | 0.85 | - | 1.16 | ) |
Environmental tobacco smoke exposure | 1.22 | ( | 0.83 | - | 1.78 | ) | 0.81 | ( | 0.57 | - | 1.16 | ) | 1.06 | ( | 0.83 | - | 1.36 | ) |
Pets | 0.74 | ( | 0.58 | - | 0.94 | ) | 0.77 | ( | 0.63 | - | 0.94 | ) | 0.89 | ( | 0.77 | - | 1.02 | ) |
Cockroaches | 1.02 | ( | 0.69 | - | 1.51 | ) | 0.99 | ( | 0.70 | - | 1.39 | ) | 1.24 | ( | 0.96 | - | 1.59 | ) |
Mould | 1.11 | ( | 0.78 | - | 1.60 | ) | 1.11 | ( | 0.80 | - | 1.53 | ) | 1.14 | ( | 0.90 | - | 1.44 | ) |