Table 2.

Univariate and multivariate odds ratio of asthma severity (GINA Step III and IV Combined) According to asthma risk factors and smoking variables

Variables	Univariate Odds Ratio (95% CI)	P value	Multivariate Odds Ratio (95% CI)	P value
Gender
Female	1.00
Male	1.14 (0.58-2.23)	P = 0.71
Age	1.07 (1.01-1.31)	P = 0.027
Family Hx of Atopy	0.76 (0.37-1.58)	P = 0.46
Model 1 (n = 61)	1.07 (0.31-3.66)	P = 0.92	1.19 (0.32-4.50)	P = 0.79
Passive Smoking
Model 2 (n = 152)		P = 0.043
Current or Former Smoker	2.10 (1.03-4.31)		1.93 (0.93-4.01)	P = 0.08
Model 3 (n = 125)
Packs per Year
Never Smoker 0	1.00		1.00
1-10 packs 1	1.31 (0.43-4.03)	P = 0.63	1.47 (0.46-4.68)	P = 0.52
11-20 packs 2	3.51 (1.39-8.83)	P = 0.008	2.85 (1.09-7.46)	P = 0.032
>20 packs 3	7.67 (2.09-28.07)	P = 0.002	5.59 (1.44-21.67)	P = 0.013
Model 4 (n = 142)
Smoking Status
Never Smoker 0	1.00		1.00
Former Smoker 1	1.28 (0.39-4.22)	P = 0.69	1.26 (0.37-4.24)	P = 0.79
Current Smoker 2	3.07 (1.43-6.57)	P = 0.004	2.78 (1.28-6.08)	P = 0.009

Model 1: Reference group are nonsmokers not exposed to passive smoking. Past and current smokers excluded.

Model 2: Reference group are nonsmokers. No exclusions.

Model 3: Past smokers and those who quit during follow up excluded.

Model 4: Those who quit smoking during follow up excluded