TABLE 3.

Adjusted hazard ratios (95% CIs) for menopause by baseline smoking behavior, stratified by genotype in European Americans

SNP	na	Current smokers vs nonsmokersb	P	na	Current smokers vs never smokersb	P	na	Former smokers vs never smokersb	P
CYP1B1*3−/−	23	0.82 (0.4–1.70)	0.59	23	1.65 (0.62–4.4)	0.32	25	3.2 (1.27–8.06)	0.01
CYP1B1*3+/− and CYP1B1*3+/+	42	2.26 (1.4–3.67)	0.001 (Pint = 0.02c)	42	2.3 (1.32–4.0)	0.003 (Pint = 0.009c)	37	0.96 (0.5–1.86)	0.9 (Pint = 0.009c)
CYP3A4*1B−/−	60	1.59 (1.03–2.44)	0.04	60	2.12 (1.26–3.56)	0.005	58	1.78 (1.04–3.06)	0.04
CYP3A4*1B+/− and CYP3A4*1B+/+	4	15.1 (3.31–69.2)	<0.0001 (Pint = 0.01c)	4	18.3 (2.75–122.01)	0.003 (Pint = 0.03c)	6	1.2 (0.2–7.31)	0.85 (Pint = 0.03c)

Hazard ratios were adjusted for baseline age and educational attainment.

SNP, single nucleotide polymorphism.

^aNumber of participants who smoked within a particular stratum of the gene variant.

^bAdjusted hazard ratios for menopause in smokers by genotype status (carrier vs noncarrier).

^cP value for the interaction of smoking status and genotype status on risk of menopause.