Evaluating the relationship between biomarkers of potential harm and biomarkers of tobacco exposure among current, past, and nonsmokers: data from the National Health and Nutrition Examination Survey 2007–2012

Figures & data

Table 1. Descriptive statistics of demographics in the study population.

Population characteristics	N^a	Weighted %^b
Age
21–35 years	4368	27.82
36–50 years	4503	30.13
51–65 years	4386	25.76
>65 years	4036	16.29
Race/ethnicity
Hispanic/Latino	4494	13.72
Black NH	3689	11.28
White NH	7604	68.01
Other NH	1506	6.99
Gender
Male	8432	47.86
Female	8861	52.14
Smoking status
Past smoker	4215	24.38
Current smoker	3663	20.93
Never smoker	9399	54.69
Cigarettes per day (only for current smokers)
1–10	2139	54.03
11–20	1112	33.07
21–30	229	8.10
30–40	117	3.83
>41	42	0.97
Body mass index (kg/m^2)	Mean (SD)	Range
	29.02 (6.78)	13.18–84.87

NH: non-Hispanic; SD: standard deviation.

a N: total number of participants in each category without using the sampling weights.

b Weighted %: percentage of participants in each category after attaching the sampling weights.

Table 2. Descriptive statistics for biomarkers of exposure (BOE) by smoking status.

BOE	Smoking status	N	Mean	Standard error	Minimum	Maximum
Serum cotinine (ng/mL)	NS	8439	6.75	0.77	0.01	599.00
	CS	3300	218.37	4.56	0.01	597.00
	PS	3841	19.66	1.96	0.01	599.00
Adjusted NNAL (ng/mg Cr)	NS	8245	27.18	3.53	0.08	33,762.00
	CS	3312	383.73	17.36	0.10	4138.88
	PS	3653	66.49	11.63	0.09	43,243.00
Adjusted PAH (ng/mg Cr)	NS	1871	134.91	7.60	2.92	3636.20
	CS	696	341.34	15.17	5.07	3102.04
	PS	833	143.16	11.17	3.30	5666.66

CS: current smokers; NNAL: 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol; NS: never smokers; PAH: polyaromatic hydrocarbons; PS: past smokers.

Table 3. Descriptive statistics for biomarkers of potential harm (BOPH) by smoking status.

BOPH	Smoking status	N	Mean	Standard error	Minimum	Maximum
WBC count (×1000 cells/μL)	NS	8516	6.82	0.037	1.6	43.9
	CS	3350	8.15	0.072	1.5	37.4
	PS	3878	6.98	0.052	1.7	42.5
Direct HDL-cholesterol (mg/dL)	NS	8417	53.54	0.266	7	156
	CS	3290	49.93	0.481	15	175
	PS	3835	53.23	0.408	13	179
LDL-cholesterol (mg/dL)	NS	4118	116.12	0.688	9	344
	CS	1524	117.11	1.261	24	341
	PS	1833	114.70	0.883	15	290
Total cholesterol (mg/dL)	NS	8417	196.30	0.626	78	475
	CS	3290	197.16	1.012	59	528
	PS	3835	197.77	0.959	75	413
Apolipoprotein (B) (mg/dL)	NS	4188	90.66	0.626	24	215
	CS	1568	94.04	0.912	28	260
	PS	1875	92.02	0.654	15	253
hs-CRP (mg/dL)	NS	5717	0.35	0.01	0.01	13.9
	CS	2363	0.45	0.022	0.01	12.2
	PS	2725	0.41	0.011	0.01	13.1

WBC: white blood cell; NS: never smokers; CS: current smokers; PS: past smokers; HDL: high-density lipoproteins; LDL: low-density lipoproteins; hs-CRP: highly sensitive C-reactive protein.

Table 4. Regression model results with serum cotinine.

	WBC		LDL		HDL		Total cholesterol		Apolipoprotein		hs-CRP
	F-value		F-value		F-value		F-value		F-value		F-value
Parameter	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value
Serum cotinine	178.74	<0.0001	0.53	0.4715	35.88	<0.0001	0.50	0.4837	0.70	0.4093	4.95	0.0332
	(0.005)		(0.005)		(−0.016)		(−0.006)		(0.004)		(0.0005)
Age	9.31	0.0046	10.89	0.0024	10.56	0.0027	27.40	<0.0001	29.63	<0.0001	0.24	0.6264
	(−0.160)		(3.577)		(1.004)		(6.674)		(3.780)		(0.008)
Race/ethnicity	15.68	0.0004	0.07	0.7870	14.19	0.0007	1.23	0.2762	3.11	0.0875	1.95	0.1720
	(−0.232)		(−0.318)		(1.437)		(−1.427)		(−1.521)		(−0.022)
Sex	0.34	0.5653	2.16	0.1511	224.51	<0.0001	3.54	0.0691	6.20	0.0182	10.14	0.0032
	(0.052)		(−2.629)		(9.672)		(4.176)		(−3.504)		(0.091)
BMI	74.07	<0.0001	4.86	0.0348	172.65	<0.0001	0.77	0.3878	28.81	<0.0001	226.49	<0.0001
	(0.075)		(0.276)		(−0.772)		(−0.114)		(0.501)		(0.037)
R^2	0.133		0.015		0.222		0.032		0.053		0.107

WBC: white blood cells; HDL: high-density lipoproteins; LDL: low-density lipoproteins; BMI: body mass index; hs-CRP: highly sensitive C-reactive protein.

p < 0.05 was considered statistically significant, a priori. F-value refers to the relative impact of each variable within the individual model. β estimate refers to the parameter estimates of the regression model. R² refers to the overall model fit.

Table 5. Regression model results with adjusted NNAL.

	WBC		LDL		HDL		Total cholesterol		Apolipoprotein		hs-CRP
	F-value		F-value		F-value		F-value		F-value		F-value
Parameter	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value
Adjusted NNAL	4.19	0.0489	0.02	0.8789	6.34	0.0170	0.0001	0.9903	0.30	0.5908	1.69	0.203
	(0.001)		(0.0004)		(−0.002)		(0.0003)		(0.001)		(0.0001)
Age	13.59	0.0008	10.62	0.0026	14.55	0.0006	26.97	<0.0001	29.10	<0.0001	0.04	0.840
	(−0.202)		(3.536)		(1.143)		(6.713)		(3.763)		(0.003)
Race/ethnicity	7.38	0.0106	0.04	0.8387	9.70	0.0039	1.41	0.2435	2.96	0.0952	0.84	0.366
	(−0.161)		(−0.238)		(1.200)		(−1.519)		(−1.462)		(−0.014)
Sex	0.05	0.8316	2.24	0.1445	225.83	<0.0001	3.78	0.0608	6.32	0.0172	6.60	0.015
	(−0.022)		(−2.725)		(9.923)		(4.299)		(−3.562)		(0.082)
BMI	48.51	<0.0001	4.57	0.0402	146.25	<0.0001	0.60	0.4437	29.19	<0.0001	237.74	<0.0001
	(0.065)		(0.264)		(−0.737)		(−0.098)		(0.493)		(0.036)
R^2	0.072		0.015		0.210		0.032		0.053		0.101

WBC: white blood cells; HDL: high-density lipoproteins; LDL: low-density lipoproteins; BMI: body mass index; hs-CRP: highly sensitive C-reactive protein; NNAL: 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol.

p < 0.05 was considered statistically significant, a priori. F-value refers to the relative impact of each variable within the individual model. β estimate refers to the parameter estimates of the regression model. R² refers to the overall model fit.

Table 6. Regression model results with adjusted 1-OHP.

	WBC		LDL		HDL		Total cholesterol		Apolipoprotein		hs-CRP
	F-value		F-value		F-value		F-value		F-value		F-value
Parameter	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value
Adjusted 1-OHP	4.55	0.0406	0.03	0.8585	8.70	0.0059	0.49	0.487	0.03	0.8749	0.88	0.3565
	(0.003)		(0.003)		(−0.013)		(−0.014)		(−0.002)		(0.0002)
Age	0.0001	0.9961	2.22	0.1462	0.18	0.6708	4.60	0.040	6.92	0.0130	2.58	0.1177
	(0.0003)		(2.731)		(0.339)		(4.868)		(3.868)		(0.047)
Race/ethnicity	5.41	0.0266	0.09	0.7618	2.36	0.1345	0.26	0.613	1.00	0.3238	0.80	0.3782
	(−0.290)		(−0.972)		(1.881)		(−1.509)		(−1.829)		(−0.017)
Sex	0.33	0.5693	0.54	0.4663	41.81	<0.0001	0.29	0.594	2.17	0.1501	3.59	0.0672
	(0.149)		(−3.109)		(8.182)		(1.974)		(−3.756)		(0.157)
BMI	7.90	0.0083	0.08	0.785	11.36	0.0020	0.05	0.826	1.62	0.2118	18.10	0.0002
	(0.076)		(0.124)		(−0.475)		(−0.107)		(0.355)		(0.030
R^2	0.090		0.011		0.186		0.023		0.056		0.190

1-OHP: 1-hydroxypyrene; WBC: white blood cells; HDL: high-density lipoproteins; LDL: low-density lipoproteins; BMI: body mass index; hs-CRP: highly sensitive C-reactive protein.

p < 0.05 was considered statistically significant, a priori. F-value refers to the relative impact of each variable within the individual model. β estimate refers to the parameter estimates of the regression model. R² refers to the overall model fit.

Table 7. BOPH regression model estimates with smoking status.

	WBC		LDL		HDL		Total cholesterol		Apolipoprotein		hs-CRP
	F-value		F-value		F-value		F-value		F-value	p-value	F-value
Parameter	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value
Smoking status	17.40	0.0002	0.97	0.3320	0.06	0.8033	0.28	0.6015	0.15	0.7035	4.59	0.0399
	(−0.269)		(1.281)		(0.098)		(0.658)		(0.279)		(−0.039)
Age	22.04	<0.0001	12.04	0.0015	14.40	0.0006	29.50	<0.0001	31.19	<0.0001	0.02	0.8909
	(−0.238)		(3.750)		(1.134)		(6.821)		(3.816)		(−0.002)
Race/ethnicity	7.42	0.0104	0.03	0.8560	9.26	0.0046	1.39	0.2477	2.91	0.0976	0.82	0.3729
	(−0.157)		(−0.211)		(1.174)		(−1.508)		(−1.448)		(−0.014)
Sex	0.02	0.9006	2.51	0.1228	207.86	<0.0001	3.42	0.0736	6.21	0.0181	6.82	0.0136
	(−0.014)		(−2.935)		(10.010)		(4.199)		(−3.636)		(0.085)
BMI	45.90	<0.0001	4.58	0.0402	138.11	<0.0001	0.69	0.4129	30.25	<0.0001	237.41	<0.0001
	(0.063)		(0.254)		(−0.728)		(−0.103)		(0.488)		(0.036)
R^2	0.060		0.015		0.206		0.032		0.053		0.101

WBC: white blood cells; HDL: high-density lipoproteins; LDL: low-density lipoproteins; BMI: body mass index; hs-CRP: highly sensitive C-reactive protein.

p < 0.05 was considered statistically significant, a priori. F-value refers to the relative impact of each variable within the individual model. β estimate refers to the parameter estimates of the regression model. R² refers to the overall model fit.

Table 8. BOPH regression model estimates with cigarette per day.

	WBC		LDL		HDL		Total cholesterol		Apolipoprotein		hs-CRP
	F-value		F-value		F-value		F-value		F-value		F-value
Parameter	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value	(β estimate)	p-value
CPD	12.17	0.0015	0.01	0.9295	15.00	0.0005	0.14	0.7068	0.19	0.6682	1.64	0.2101
	(0.663)		(0.261)		(−3.274)		(−1.204)		(0.836)		(0.114)
Age	0.02	0.8787	1.78	0.1920	1.030	0.3175	4.69	0.0381	4.24	0.0479	0.86	0.3610
	(−0.016)		(3.724)		(1.019)		(6.807)		(4.002)		(0.052)
Race/ethnicity	0.77	0.3870	0.01	0.9354	1.54	0.2237	0.20	0.6566	0.22	0.6387	0.02	0.8784
	(−0.149)		(0.219)		(1.158)		(−1.419)		(−0.815)		(0.008)
Sex	0.16	0.6934	0.45	0.5082	15.23	0.0005	0.03	0.8599	0.90	0.3504	1.09	0.3046
	(0.096)		(−2.636)		(5.639)		(1.001)		(−3.185)		(−0.119)
BMI	16.05	0.0004	1.58	0.2187	87.13	<0.0001	0.05	0.8206	14.65	0.0006	22.88	<0.0001
	(0.085)		(0.292)		(−0.833)		(−0.063)		(0.640)		(0.040)
R^2	0.098		0.013		0.160		0.021		0.055		0.075

WBC: white blood cells; HDL: high-density lipoproteins; LDL: low-density lipoproteins; CPD: cigarettes per day use; BMI: body mass index; hs-CRP: highly sensitive C-reactive protein.

p < 0.05 was considered statistically significant, a priori. F-value refers to the relative impact of each variable within the individual model. β estimate refers to the parameter estimates of the regression model. R² refers to the overall model fit.