. 2017 Sep 26;125(9):097020. doi: 10.1289/EHP1302

Table 4.

Adjusted odds ratios (aORs) and 95% confidence intervals (95% CIs) for the association between polybrominated biphenyl (PBB)-153, polychlorinated biphenyl (PCB)-118 and $Σ PCB$ (nanograms/milliliter) and thyroid disease among Michigan females, 2004–2015.

Exposure	Total^b	All thyroid disease^a		Hypothyroidism
Exposure	Total^b	$n$ (%)^c	aOR (95% CI)	$n$ (%)^d	aOR (95% CI)
PBB-153
PBB-153 ln-transformed ( $Δ IQR = 0.43 ng / mL$ )^e^,^f	447	105 (23.5)	1.12 (0.83, 1.52)	49 (11.8)	1.35 (0.86, 2.13)
PBB-153 Q1 ( $< LOD - \leq 0.03 ng / mL$ )	100	12 (12.0)	1.00 (Reference)	8 (8.0)	1.00 (Reference)
PBB-153 Q2 ( $> 0.03 - \leq 0.16 ng / mL$ )	91	22 (24.2)	1.53 (0.63, 3.76)	9 (10.6)	1.22 (0.37, 4.03)
PBB-153 Q3 ( $> 0.16 - \leq 0.30 ng / mL$ )	88	23 (26.1)	1.30 (0.49, 3.45)	8 (10.3)	1.08 (0.32, 3.64)
PBB-153 Q4 ( $> 0.30 - \leq 0.63 ng / mL$ )	92	31 (33.7)	2.89 (1.11, 7.49)	14 (17.1)	3.43 (1.08, 10.90)
PBB-153 Q5 ( $> 0.63 - 128 (maximum) ng / mL$ )	87	19 (21.8)	1.44 (0.53, 3.94)	11 (13.6)	2.19 (0.67, 7.23)
PCB-118
PCB-118 ln-transformed ( $Δ IQR = 0.07 ng / mL$ )^e	378	107 (28.3)	1.20 (0.89, 1.63)	48 (14.1)	1.39 (0.90, 2.13)
PCB-118 Q1 ( $< LOD - < 0.02 ng / mL$ )	80	15 (18.8)	1.00 (Reference)	10 (12.7)	1.00 (Reference)
PCB-118 Q2 ( $\geq 0.02 - < 0.05 ng / mL$ )	79	20 (25.3)	1.13 (0.48, 2.66)	9 (11.8)	0.72 (0.25, 2.05)
PCB-118 Q3 ( $\geq 0.05 - < 0.08 ng / mL$ )	79	19 (24.1)	0.95 (0.40, 2.25)	9 (12.5)	0.69 (0.26, 1.87)
PCB-118 Q4 $\geq 0.08 - < 0.13 ng / mL$ )	80	25 (31.3)	1.19 (0.52, 2.73)	11 (15.9)	0.98 (0.37, 2.62)
PCB-118 Q5 ( $\geq 0.13 - 0.89 (maximum) ng / mL$ )	75	31 (41.3)	1.39 (0.59, 3.27)	11 (18.3)	1.59 (0.57, 4.43)
$Σ PCB$ (di-ortho)^g
$\sum PCB$ ln-transformed ( $Δ IQR = 0.74 ng / mL$ )^e	455	113 (24.8)	1.13 (0.77, 1.68)	52 (12.4)	1.46 (0.89, 2.40)
$\sum PCB$ Q1 ( $0.03 - < 0.19 ng / mL$ )	96	16 (16.7)	1.00 (Reference)	10 (10.4)	1.00 (Reference)
$\sum PCB$ Q2 ( $\geq 0.19 - < 0.41 ng / mL$ )	94	15 (16.0)	0.77 (0.33, 1.80)	5 (5.5)	0.37 (0.11, 1.32)
$\sum PCB$ Q3 ( $\geq 0.41 - < 0.68 ng / mL$ )	97	26 (26.8)	1.02 (0.46, 2.25)	15 (16.9)	1.20 (0.49, 2.94)
$\sum PCB$ Q4 ( $\geq 0.68 - < 1.11 ng / mL$ )	96	25 (26.0)	0.80 (0.36, 1.80)	9 (10.6)	0.59 (0.22, 1.57)
$\sum PCB$ Q5 ( $\geq 1.11 - 5.95 (maximum) ng / mL$ )	95	36 (37.9)	1.22 (0.56, 2.68)	16 (20.0)	1.70 (0.69, 4.15)

Note: IQR, interquartile range; LOD, limit of detection; Q1–Q5, quintiles 1 through 5. Models for PBB-153 and $Σ PCB$ (di-ortho) control for lipids, age, study phase, and smoking status; models for PCB-118 do not control for study phase because all samples from Phase 1 were not reportable owing to instrumentation error [see Tables S4 and S5 for information on individual PCB congeners (PCB-138, 153, and 180).]

^{^a}

Includes those who specified physician-diagnosed thyroid disease ( $n = 107$ ) and those who had thyroid hormone concentrations outside clinically normal ranges ( $n = 6$ ); includes 10 hyperthyroid, 52 hypothyroid, 14 other types, and 37 type not specified.

^{^b}

PBB-153 analyses exclude 8 women who were diagnosed with thyroid disease before the contamination event; PCB-118 analyses exclude 88 women (89 samples) who had missing values owing to unstable retention time on laboratory instrument; $Σ PCB$ (di-ortho) analyses include all observations.

^{^c}

30 women participated multiple times, so cell counts may not sum to total.

^{^d}

Hypothyroidism analyses exclude 37 observations owing to lack of information on thyroid disease type (32 in PBB-153 model); these are excluded from denominator of percent calculations.

^{^e}

All IQRs and quintiles calculated among women only.

^{^f}

PBB-153 concentrations below the LOD were imputed using a distribution-based multiple imputation approach.

^{^g}

$PCB - 138 + PCB - 153 + PCB - 180$ .