Table 2.

Association between allergic disease and attention deficit (hyperactivity) disorder (ADD/ADHD) in U.S. children and adolescents (n = 354 416)

Allergic disease	ADD/ADHD
	No (n = 32 504)	Yes (n = 173)
	Freq	Freq	% Prev (95% CI)	Crude OR (95% CI)	Adjusted OR (95% CI)	Adjusted OR 2 (95% CI)
None	225 654	14 492	6·0 (5·9–6·1)	1·00 (ref)	1·00 (ref)	1·00 (ref)
Eczema only	17 813	1402	7·3 (6·9–7·7)	1·23 (1·16–1·30)	1·41 (1·33–1·50)	1·30 (1·22–1·38)
Asthma only	21 461	2630	10·9 (10·5–11·3)	1·91 (1·83–1·99)	1·58 (1·50–1·66)	1·41 (1·34–1·48)
Hay fever only	32 389	3177	8·9 (8·6–9·2)	1·53 (1·47–1·59)	1·28 (1·22–1·34)	1·13 (1·08–1·19)
Eczema and asthma	3117	420	11·9 (10·8–12·9)	2·10 (1·89–2·33)	2·06 (1·84–2·31)	1·68 (1·49–1·89)
Eczema and hay fever	6629	717	9·8 (9·1–10·4)	1·68 (1·56–1·82)	1·65 (1·51–1·80)	1·33 (1·21–1·45)
Asthma and hay fever	13 521	1995	12·9 (12·3–13·4)	2·30 (2·19–2·42)	1·75 (1·66–1·85)	1·38 (1·30–1·46)
Eczema, asthma and hay fever	4741	805	14·5 (13·6–15·4)	2·65 (2·45–2·86)	2·32 (2·13–2·53)	1·61 (1·47–1·76)

Binary, unweighted logistic regression models were constructed with ADHD as the dependent variable and allergic disease as the independent variable. Multivariate logistic regression models were then constructed that included eczema, sex, age, race, household income, highest level of household education, U.S. vs. foreign birthplace and insurance coverage as the independent variables. A second multivariate model was created that additionally controlled for healthcare utilization in the past year. Adjusted prevalence ORs and 95% CIs were estimated. CI, confidence interval; freq, frequency; OR, odds ratio; prev, prevalence; bold indicates significance.