Table 2.

Multivariable-Adjusted Odds Ratios for Elevated Levels of Inflammation Biomarkers by Quintile of Toenail Selenium Level, CARDIA Trace Element Study, 1987–2005^a

Inflammation Biomarker	Quintile of Toenail Selenium Level									P for Trendb
	1	2		3		4		5
	(Referent)	OR	95% CI	OR	95% CI	OR	95% CI	OR	95% CI
Fibrinogen (>460 mg/dL)
No. of participants	798	799		809		797		798
No. of events	170	163		172		168		168
Model 1c	1.00	1.16	0.90, 1.50	1.01	0.78, 1.31	1.02	0.77, 1.34	1.03	0.78, 1.36	0.82
Model 2d	1.00	1.29	0.99, 1.67	1.10	0.84, 1.43	1.13	0.85, 1.51	1.02	0.76, 1.37	0.70
Model 3e	1.00	1.28	0.99, 1.67	1.12	0.85, 1.46	1.15	0.86, 1.53	1.03	0.77, 1.38	0.76
High-sensitivity C-reactive protein (>3 μg/mL)
No. of participants	770	776		780		762		781
No. of events	339	318		332		318		309
Model 1	1.00	1.11	0.92, 1.34	1.00	0.82, 1.22	1.06	0.87, 1.30	1.14	0.93, 1.40	0.30
Model 2	1.00	1.13	0.93, 1.38	0.97	0.79, 1.19	1.06	0.86, 1.30	1.03	0.83, 1.28	0.99
Model 3	1.00	1.13	0.93, 1.37	0.97	0.79, 1.18	1.04	0.85, 1.28	1.02	0.83, 1.27	0.92
Interleukin-6 (>3.395 pg/mL, 80th percentile)
No. of participants	572	628		613		628		638
No. of events	134	118		137		104		123
Model 1	1.00	0.83	0.62, 1.11	1.10	0.82, 1.46	0.72	0.53, 0.99	0.88	0.65, 1.21	0.34
Model 2	1.00	0.83	0.62, 1.12	1.14	0.85, 1.54	0.75	0.54, 1.04	0.97	0.70, 1.35	0.79
Model 3	1.00	0.84	0.62, 1.14	1.15	0.85, 1.55	0.77	0.55, 1.06	0.98	0.71, 1.36	0.82

Abbreviations: CARDIA, Coronary Artery Risk Development in Young Adults; CI, confidence interval; OR, odds ratio.

^aGeneralized estimating equations with binary outcomes were used for repeated measurements of fibrinogen and high-sensitivity C-reactive protein; a logistic regression model was used for interleukin-6.

^bAn ordinal selenium variable using the median toenail selenium level in each quintile was created for the trend tests.

^cAdjusted for age, gender (male, female), race/ethnicity (African-American, Caucasian), and study center.

^dAdditionally adjusted for education (≤12, 13–15, or ≥16 years), smoking status (never smoker, former smoker, or current smoker), alcohol consumption (0, 0.1–11.9, 12.0–23.9, or ≥24 mL/day), physical activity score (quintiles), body mass index (weight (kg)/height (m)²; <21, 21–22.9, 23–24.9, 25–29.9, ≥30), and toenail mass (mg; quintiles).

^eAdditionally adjusted for intakes (quintiles) of vitamin C, folic acid, zinc, vitamin E, and β-carotene at baseline.