Ever dispense of prescribed allergy medication in children growing up close to traffic: a registry-based birth cohort

Table 2 Adjusted HR (95 % CI) for allergy medication, in relation to traffic-related exposure, n = 7898

Allergy medication^a
	Nasal anti-allergics	Oral antihistamine
	1st purchase	1st purchase
Heaviest road ≤100 m, birth address^b
0–8639 cars/day	1.0	1.0
≥ 8640	0.89 (0.61–1.29)	0.91 (0.83–1.00)
Heaviest road ≤100 m, never moved^b
0–8639 cars/day	1.0	1.0
≥ 8640	0.83 (0.51–1.36)	0.90 (0.79–1.03)
NO_X, birth address^c
≤ 15 μg/m³	1.0	1.0
15–25	0.84 (0.58–1.21)	0.86 (0.77–0.95)
> 25	0.86 (0.50–1.49)	0.81 (0.68–0.96)
NO_X, never moved^c
≤ 15 μg/m³	1.0	1.0
15–25	0.95 (0.62–1.47)	0.88 (0.78–0.99)
> 25	0.95 (0.42–2.16)	0.77 (0.62–0.96)
NO_X, lifetime mean^d
≤ 15 μg/m³	1.0	1.0
15–25	0.92 (0.62–1.35)	0.84 (0.75–0.93)
> 25	0.59 (0.23–1.50)	0.70 (0.56–0.89)

^aAdjusted for sex, season, parental origin, year of birth, breastfeeding, and parental allergy
^bn = 6093 children had complete covariate information and traffic exposure assessments
^cn = 6091 children had complete covariate information and modeled NOx concentrations
^dThe number of children with complete covariate information and modeled mean NOx during time at risk, was n = 5264 for nasal antiallergics, and n = 5317 for oral antihistamines

ISSN: 1471-2458