Table 3.

Adjusted odds ratio (OR) and 95% CI of prevalent metabolic syndrome by category of six BFRs (n = 637)^*

Analyte	Not detectable	Detectable				P trend‡	P quadratic
		<25th†	25th to <50th	50th to <75th	≥75th
PBB-153
Median serum concentration (ng/g of lipid)	—	1.2	2.3	3.8	13.1
Cases/n	18/82	38/137	65/145	59/137	57/136
Adjusted OR (95% CI)	Referent	1.5 (0.7–3.2)	3.1 (1.4–6.5)	3.1 (1.4–6.7)	3.1 (1.4–6.9)	<0.01	0.07
PBDE-28
Median serum concentration (ng/g of lipid)	—	0.7	1.2	2.0	5.4
Cases/n	50/142	41/149	44/107	50/116	52/123
Adjusted OR (95% CI)	Referent	0.8 (0.4–1.5)	1.7 (0.9–3.1)	1.5 (0.8–2.8)	1.3 (0.7–2.4)	0.09	0.49
PBDE-47
Median serum concentration (ng/g of lipid)	—	6.5	13.7	28.2	73.3
Cases/n	6/20	64/170	58/161	55/142	54/144
Adjusted OR (95% CI)	Referent	1.1 (0.3–3.5)	0.8 (0.3–2.8)	1.2 (0.4–4.0)	1.1 (0.3–3.6)	0.70	0.72
PBDE-99
Median serum concentration (ng/g of lipid)	—	3.1	5.3	9.2	26.9
Cases/n	82/223	50/122	34/99	37/88	34/105
Adjusted OR (95% CI)	Referent	1.1 (0.7–2.0)	1.0 (0.6–1.8)	1.9 (1.0–3.5)	0.8 (0.5–1.5)	0.75	0.24
PBDE-100
Median serum concentration (ng/g of lipid)	—	1.4	2.8	5.6	16.8
Cases/n	16/52	67/164	53/136	47/144	54/141
Adjusted OR (95% CI)	Referent	1.8 (0.8–4.1)	1.5 (0.6–3.4)	1.6 (0.7–3.6)	1.7 (0.7–3.8)	0.68	0.61
PBDE-153
Median serum concentration (ng/g of lipid)	—	1.9	3.6	6.6	24.6
Cases/n	19/52	65/162	54/133	52/143	47/147
Adjusted OR (95% CI)	Referent	2.1 (1.0–4.6)	2.5 (1.1–5.6)	2.4 (1.0–5.3)	1.7 (0.7–3.8)	0.69	0.02

^*Adjusted for age, sex, race, poverty income ratio, BMI, cigarette smoking, serum cotinine, alcohol consumption, and exercise.

^†Displayed is the median serum concentration in each category.

^‡P trend was calculated without a quadratic term in the model, while P quadratic was calculated including the linear term.