Longitudinal change in blood DNA epigenetic signature after smoking cessation

Figures & data

Table 1. Participant demographic and blood count characteristics by longitudinal smoking status.

	Current-current smokers (n = 112)	Interim quitters (n = 147)	Former-former smokers (n = 115)	Never smokers (n = 47)
Age at baseline, years	57.9 ± 7.7	52.6 ± 10.2	57.7 ± 7.0	55.0 ± 5.5
Age at follow-up, years	68.8 ± 7.7	65.9 ± 13.0	71.9 ± 6.2	76.0 ± 5.6
Female, %	58%	37%	45%	47%
Cell count, baseline
CD8T cell fraction	0.12 ± 0.05	0.11 ± 0.05	0.13 ± 0.05	0.12 ± 0.04
CD4T cells	0.19 ± 0.07	0.19 ± 0.06	0.19 ± 0.06	0.18 ± 0.06
NK cells	0.03 ± 0.04	0.05 ± 0.05	0.05 ± 0.05	0.11 ± 0.05
B cells	0.07 ± 0.03	0.06 ± 0.03	0.07 ± 0.03	0.08 ± 0.04
Monocytes	0.09 ± 0.02	0.09 ± 0.03	0.09 ± 0.03	0.09 ± 0.03
Granulocytes	0.50 ± 0.11	0.51 ± 0.12	0.47 ± 0.12	0.43 ± 0.12
Cell count, follow-up
CD8T cell fraction	0.11 ± 0.04	0.11 ± 0.05	0.11 ± 0.06	0.10 ± 0.04
CD4T cells	0.19 ± 0.07	0.18 ± 0.07	0.17 ± 0.07	0.16 ± 0.07
NK cells	0.03 ± 0.04	0.07 ± 0.07	0.09 ± 0.07	0.13 ± 0.06
B cells	0.06 ± 0.02	0.06 ± 0.03	0.06 ± 0.05	0.06 ± 0.04
Monocytes	0.10 ± 0.02	0.10 ± 0.03	0.11 ± 0.03	0.11 ± 0.03
Granulocytes	0.52 ± 0.09	0.48 ± 0.11	0.48 ± 0.13	0.45 ± 0.13

Abbreviations: NK, natural killer

Figure 1. Study sample smoking status categories.

Table 2. Differences in delta β values for CpG sites differing between interim quitters (n = 147) and current-current smokers (n = 112) at FDR < 0.05.

CpG site	Location (hg19)	Gene symbol	Difference in delta β± SE	FDR	Cohort-specific delta β direction (FHS, ARIC)*
cg05575921	chr5:373378	AHRR	0.0414 ± 0.0044	4.69E-15	++
cg23576855	chr5:373299	AHRR	0.0332 ± 0.0052	3.08E-05	++
cg14817490	chr5:392920	AHRR	0.0208 ± 0.0038	0.007	++
cg26703534	chr5:377358	AHRR	0.0187 ± 0.0035	0.007	++
cg21566642	chr2:233284661	–	0.0205 ± 0.0039	0.010	++
cg03636183	chr19:17000585	F2RL3	0.0195 ± 0.0037	0.014	++

* + indicates a positive cohort-specific delta β value, – indicates a negative cohort-specific delta β value.

Abbreviations: CpG, cytosine-phosphate-guanine; SE, standard error; FDR, false discovery rate; FHS, Framingham Heart Study; ARIC, Atherosclerosis Risk in the Community; AHRR, aryl hydrocarbon receptor repressor; F2RL3, coagulation factor II receptor-like 3

Table 3. Differences in delta β values for CpG sites differing between current-current smokers (n = 112) and all non-smoking categories (n = 309) at FDR < 0.05.

CpG site	Location (hg19)	Gene symbol	Difference in delta β± SE	FDR	Cohort-specific delta β direction (FHS, ARIC)*
cg05575921	chr5:373378	AHRR	−0.0407 ± 0.004	4.80E-18	–
cg23576855	chr5:373299	AHRR	−0.0327 ± 0.0047	7.52E-07	–
cg26703534	chr5:377358	AHRR	−0.0212 ± 0.0031	1.42E-06	–
cg14817490	chr5:392920	AHRR	−0.0195 ± 0.0034	0.001	–
cg03636183	chr19:17000585	F2RL3	−0.0188 ± 0.0034	0.002	–
cg21566642	chr2:233284661	–	−0.0187 ± 0.0035	0.006	–
cg16145216	chr1:42385662	HIVEP3	0.0134 ± 0.0026	0.015	++
cg24639862	chr11:85359006	TMEM126A	0.0009 ± 0.0002	0.030	++
cg14339116	chr9:77062053	–	0.0059 ± 0.0012	0.044	++

* + indicates a positive cohort-specific delta β value, – indicates a negative cohort-specific delta β value.

Abbreviations: CpG, cytosine-phosphate-guanine; SE, standard error; FDR, false discovery rate; FHS, Framingham Heart Study; ARIC, Atherosclerosis Risk in the Community; AHRR, aryl hydrocarbon receptor repressor; F2RL3, coagulation factor II receptor-like 3; HIVEP3, human immunodeficiency virus type I enhancer-binding protein 3; TMEM126A, transmembrane protein 126A