Table 5.

Results of stepwise multiple logistic regression analysis for the GSTM1 genotype (variable): final significant variables in the model

Risk Factor (variables)	Odds ratio	[95% C.I]	pvalue
GSTM1 Genotype (Mwild vs. Mnull)	8.90	6.32 – 12.5	< .001
Hypertension	2.49	1.74 – 3.57	< .001
Hypercholesterolemia	1.39	1.10 – 1.81	.015
Obesity	2.10	1.59 – 2.75	< .001
Smoking	2.82	1.87 – 4.28	< .001
Genotype (Mwild vs. Mnull) × smoking	0.469	0.26 – 0.85	.012

GSTM1 genotype × smoking interaction was entered jointly into the multiple logistic regression analysis. Other factors were entered disjointedly. After analysis, the genotype × smoking interaction was retained in the model and therefore is shown in the above table.