TABLE 2.

Basic characteristics of participants by Oxidative Balance Score quartile.

Characteristics	Oxidative Balance Score				P-value
	Q1 N = 927	Q2 N = 926	Q3 N = 926	Q4 N = 927
Age (years)	54.80 ± 15.29	53.43 ± 14.49	52.97 ± 14.39	52.61 ± 14.24	0.018
Periodontitis, (%)					<0.001
Yes	75.13	70.58	63.44	52.67
No	24.87	29.42	36.56	47.33
Sex, (%)					<0.001
Male	36.57	47.08	55.83	62.89
Female	63.43	52.92	44.17	37.11
Race/Ethnicity, (%)					<0.001
Non-Hispanic white	47.03	48.16	51.51	54.37
Non-Hispanic black	21.47	17.93	15.01	11.87
Mexican American	15.53	17.49	19.33	19.20
Other race/Multiracial	15.97	16.42	14.15	14.56
Education level, n (%)					<0.001
Less than high school	37.22	30.67	27.11	22.33
High school	25.89	21.60	23.33	18.55
More than high school	36.89	47.73	49.56	59.12
Smoking, (%)					0.206
Ever	50.05	46.44	47.30	45.31
Never	49.95	53.56	52.70	54.69
Drinking alcohol, (%)					0.006
Ever	71.81	61.12	62.35	58.37
Never	28.19	38.88	37.65	41.63
Cancer, (%)					0.341
Yes	10.79	9.83	9.18	12.51
No	89.21	90.17	90.82	87.49
Diabetes, (%)					0.001
Yes	15.43	15.77	10.04	10.25
No	82.31	81.97	87.58	86.95
Borderline	2.26	2.26	2.38	2.80
BMI (kg/m2)	30.02 ± 6.99	29.98 ± 6.84	29.29 ± 6.21	28.69 ± 6.06	<0.001
Waist circumference (cm)	101.30 ± 15.91	101.69 ± 16.10	100.37 ± 14.98	98.99 ± 14.52	0.002
PIR	2.18 ± 1.51	2.46 ± 1.58	2.70 ± 1.63	3.00 ± 1.66	<0.001
Triglycerides (mg/dL)	141.84 ± 129.14	134.99 ± 106.87	139.92 ± 107.54	132.09 ± 143.62	0.514
Klotho (pg/mL)	813.23 ± 303.24	817.82 ± 277.08	831.34 ± 271.82	815.73 ± 313.40	0.823
LDL-C (mg/dL)	119.76 ± 34.45	120.93 ± 35.04	121.05 ± 35.01	116.19 ± 33.77	0.184
Serum cotinine (ng/ml)	98.92 ± 153.72	51.32 ± 122.73	36.25 ± 101.03	29.92 ± 95.40	<0.001

Mean ± SD for continuous variables: the P-value was calculated by the weighted linear regression model. (%) for categorical variables: the P-value was calculated by the weighted chi-square test. Q, quartile; PIR, ratio of family income to poverty; BMI, body mass index; LDL-C, low-density lipoprotein cholesterol.