Table 4
Association between asthma and WC
Variables	Asthma confirmed by BHR			Previous asthma diagnosis
	N	cases	OR (95% CI)	N	cases	OR (95% CI)
WC	1921	200		1921	284
normal	1300	141	1	1300	193	1
abnormal	621	59	0.96 (0.69 – 1.33)	621	91	1.32 (1.00 – 1.75)
Physical activity	1922	200		1922	284
Active	1113	97	1	1113	149	1
Inactive	809	103	1.16 (0.85 - 1.58)	801	135	1.35 (1.04 – 1.76)
Gender	1922	200		1922	284
Male	942	67	1	942	144	1
Female	980	133	2.16 (1.56 – 2.99)	980	140	0.84 (0.65 – 1.09)
Smoking habit	1922	200		1922	284
Non-smokers	1588	156	1	1588	234	1
Smokers	334	44	1.48 (1.02 – 2.14)	334	50	1.01 (0.72 - 1.41)
Schooling (years)	1922	200		1922	294
≥ 12	282	45	1	282	35	1
9-11	978	118	0.74 (0.51 – 1.09)	978	144	1.27 (0.85 – 1.90)
≤ 8	662	37	0.31 (0.19 – 0.49)	662	105	1.47 (0.97 – 2.23)

N: number of subjects.

cases: numbers of subjects with asthma in every category.

CI: confidence interval.

OR: odds ratio.

WC: waist circumference.

BHR: bronchial hyperresponsiveness.

Analysis was adjusted for gender, socioeconomic level, smoking status and physical activities.

Multivariate analysis.

Cetlin et al. BMC Public Health 2012 12:844   doi:10.1186/1471-2458-12-844