Table 1.

Demographics of the study population

	Cases/controls	Cases/controls with EIB	Gender (male/female)	Age, years Mean (95% CI)	Body mass index GM (95% CI)	Total IgE, IU/mL GM (95% CI)
Total*	88/93†	34/1	92/89	11.9 (11.6–12.2)	17.2 (16.8–17.6)	258 (204–326)
Communities
Urban affluent	35/35	20/1	28/42	11.7 (11.3–12.1)	18.3 (17.6–19.0)‡	166 (110–251)‡
Urban poor	30/33	5/0	34/29	11.7 (11.3–12.1)	16.7 (16.2–17.2)	331 (226–485)
Suburban/rural	23/25	9/0§	30/18	12.3 (11.7–13.0)	16.4 (15.8–17.1)	351 (233–528)

^*Of 1848 children who participated in the cross-sectional study, 935 were male (50.6%).

^†Of the 99 children with physician-diagnosed asthma (cases), 51 were male (51.5%) while 50.8% of the controls were male.

^‡BMI was significantly higher (P<0.01) and total IgE was significantly lower (P<0.03) in the urban affluent school.

^§Within the suburban/rural community, one case and one control did not complete the exercise challenge.

CI, confidence interval; BMI, body mass index.