Table 4.

Associations between nutrient supplement, serum biomarkers and air pollutants exposure levels and CHD

	Controls N(%)	Cases N(%)	COR	AOR#
Nutrient supplement
FA
Irregularly	30(39.0)	21(39.6)	Reference	Reference
Regularly	47(61.0)	32(60.4)	0.97(0.48–1.99)	1.13(0.52–2.44)
Multivitamin
Irregularly	43(55.8)	39(73.6)	Reference	Reference
Regularly	34(44.2)	14(26.4)	0.45(0.21–0.97)*	0.58(0.26–1.30)
Serum biomarkers a
Folate
Low(≤ 34.55 nmol/L)	58(75.3)	21(39.6)	Reference	Reference
High(>34.55 nmol/L)	19(24.7)	32(60.4)	2.53(1.20–5.34)*	3.03(1.33–6.88)**
Vitamin B12
Low(≤ 370 pmol/L)	58(75.3)	44(83.0)	Reference	Reference
High(>370 pmol/L)	19(24.7)	9(17.0)	0.62(0.26–1.51)	0.79(0.31–2.07)
Homocysteine
Low(≤ 6.125µmol/L)	58(75.3)	24(45.3)	Reference	Reference
High(>6.125µmol/L)	19(24.7)	29(54.7)	3.69(1.70–7.80)**	2.98(1.31–6.36)**
Indoor air pollution
TVOCsa
Low(≤ 0.0165 mg/m3)	58(75.3)	12(22.6)	Reference	Reference
High(>0.0165 mg/m3)	19(24.7)	41(77.4)	10.43(4.57–23.82)***	9.23(3.78–22.53)***
Benzeneb
Low(≤ 0.01 mg/m3)	68(88.3)	31(58.5)	Reference	Reference
High(>0.01 mg/m3)	9(11.7)	22(41.5)	5.36(2.22–12.98)***	4.56(1.75–11.89)**

#Adjusted for maternal age, maternal education level, paternal education level, and residence. *Significant differences (p < 0.05) between the case and control groups are indicated. ** Significant differences (p < 0.01) between the case and control groups are indicated. *** Significant differences (p < 0.001) between the case and control groups are indicated. a: Serum folate, Vitamin B12, homocysteine and TVOCs exposure levels were categorized into low and high concentrations based on the 75th percentile of the control group. b: Benzene exposure levels were categorized into low and high concentrations based on the MDL