Table 3.

Association between body mass index genetic risk score and classes of smoking initiation (odds ratios).

	Class (percentage membership)
	Never	Experimenters	Late Onset	Early Onset	P value
Males (n = 1768)	1.00 (REF)	0.90 (0.70, 1.11)	0.94 (0.75, 1.12)	1.00 (0.62, 1.37)	0.69
Females (n = 2249)	1.00 (REF)	1.09 (0.94, 1.23)	0.96 (0.74, 1.18)	1.21 (0.93, 1.48)	0.45
Total (n = 4017)	1.00 (REF)	1.02 (0.90, 1.14)	0.95 (0.80, 1.09)	1.14 (0.92, 1.36)	0.66

Odds ratios are per 1 standard deviation increase in body mass index genetic risk score.