Table 2.

Statistically significant results of the analysis of longitudinal effect of continued smoking

CpG site	CHR	Gene or region	Cross-sectional coefficient	Longitudinal coefficient	Longitudinal coefficient p-value	Median methylations (CS vs NS) diverging or converging from baseline to follow-up
cg13184736	1	GNG12	−0.339	−0.019	1.36E-05	Div.
cg25189904	1	GNG12	−0.507	−0.016	1.26E-06	Div.
cg23079012	2	2p25.1	−0.887	0.039	3.82E-09	Con.
cg05575921	5	AHRR	−2.575	0.061	7.83E-05	Con.
cg09338136	5	AHRR	−0.156	0.011	5.29E-18	Con.
cg06126421	6	6p21.33	−0.697	−0.017	1.23E-08	Con.a
cg14753356	6	6p21.33	−0.237	−0.012	7.94E-07	Div.
cg12147622	10	10q22.1	−0.125	−0.012	8.05E-05	Div.
cg05875421	14	GPR68	−0.211	0.017	1.23E-05	Con.
cg15022400	15	TRIM69	−0.112	−0.012	3.37E-06	Div.
cg23161492	15	ANPEP	−0.306	−0.010	5.69E-05	Div.
cg07251887	17	LOC100130933	−0.132	−0.011	5.26E-07	Div.
cg25512107	17	RPTOR	−0.336	0.037	2.48E-08	Con.
cg15187398	19	MOBKL2A	−0.161	−0.010	8.51E-06	Div.

CHR: chromosome of the CpG site; CS: current smokers; NS: never smokers

^amethylation levels are converging, but the longitudinal and cross-sectional coefficients are of the same sign

Legend: Presented are the 14 CpG sites significant for the longitudinal coefficient in the continued smoking analysis. The longitudinal coefficient represents the difference in rate of change of methylation M-value between baseline and follow-up for the individuals who were smokers at both time points relative to the individuals who were never smokers at both time points. Also presented is the cross-sectional coefficient, which represents the difference in methylation at baseline for the same two groups. A CpG site is labelled as “diverging” if the median methylations between the two groups separate further from baseline to follow-up; a CpG site is labelled as “converging” if the median methylations between the two groups approach one another from baseline to follow-up