Association of Triglyceride-Glucose Index with Risk of Large for Gestational Age: A Prospective Cohort Study

Figures & data

Figure 1 Flowchart of subject selection.

Table 1 Basic Characteristics of the Study Population by Triglyceride-Glucose (TyG) Index Quartile

Variable	Overall	TyG Quartile				P value
	Total (n=12,108)	Q1 (n=3001)	Q2 (n=2997)	Q3 (n=3064)	Q4 (n=3046)
TYG index	8.46±0.34	<8.23	8.23–8.45	8.45–8.68	≥8.68
Maternal age (years)	30.16±3.91	29.46±3.71	29.82±3.75*	30.24±3.95*	30.16±3.92*	<0.001
Education level, n(%)						<0.001
College and above	9591(79.2)	2519(83.9)	2403(80.2)*	2417(78.9)*	2252(73.9)*
High school or equivalent	1565(12.9)	311(10.4)	384(12.8)*	413(13.5)*	457(15.0)*
Less than high school	952(7.9)	171(5.7)	210(7.0)*	234(7.6)*	337(11.1)*
Marital status, n(%)						0.002
Married	11,580(95.6)	2842(94.7)	2869(95.7)	2924(95.4)	2945(96.7)*
Never married	528(4.4)	159(5.3)	128(4.3)	140(4.6)	101(3.3)*
Pre-pregnancy BMI (kg/m^2), n(%)						<0.001
Underweight (BMI<18.5)	1923(15.9)	666(22.2)	542(18.1)	462(15.1)*	253(8.3)*
Normal weight (BMI 18.5~23.9)	8537(70.5)	2139(71.3)	2160(72.1)	2164(70.6)	2074(68.1)*
Overweight (BMI≥ 24.0)	1648(13.6)	196(6.5)	295(9.8)*	438(14.3)*	719(23.6)*
Gravidity, n(%)						<0.001
1(%)	5281(43.6)	1589(52.9)	1440(48.0)*	1270(41.4)*	982(32.2)*
2(%)	3695(30.5)	794(26.5)	891(29.7)*	973(31.8)*	1037(34.0)*
≥3(%)	3132(25.9)	618(20.6)	666(22.2)	821(26.8)*	1027(33.7)*
Parity, n(%)						<0.001
Primiparous	7182(59.3)	2073(69.1)	1917(64.0)*	1750(57.1)*	1442(47.3)*
Multiparous	4926(40.7)	928(30.9)	1080(36.0)*	1314(42.9)*	1604(52.7)*
Smoking, n(%)						0.491
Yes	240(2.0)	58(1.9)	69(2.3)	54(1.8)	59(1.9)
No	11,868(98.0)	2943(98.1)	2928(97.7)	3010(98.2)	2987(98.1)
FPG at first trimester, mmol/L	4.72±0.37	4.60±0.34	4.68±0.31*	4.75±0.34*	4.85±0.445*	<0.001
Systolic blood pressure at first trimester, mm Hg	114.61±10.87	113.02±10.58	113.57±10.79	115.11±10.90	116.71±10.83	0.085
Diastolic blood pressure at first trimester, mm Hg	69.31±8.63	67.79±8.45	68.70±8.52	69.66±8.66	70.86±8.60	0.825
HDL-C at first trimester, mmol/L	1.678±0.30	1.73±0.29	1.71±0.29*	1.68±0.30*	1.59±0.30*	<0.001
LDL-C at first trimester, mmol/L	2.39±0.60	2.14±0.52	2.31±0.53	2.47±0.59	2.63±0.633	<0.001
TC at first trimester, mmol/L	4.63±0.734	4.34±0.65	4.54±0.66	4.71±0.72	4.92±0.77	0.087
TG at first trimester, mmol/L	1.34±0.494	0.864±0.13	1.13±0.10*	1.38±0.13*	1.98±0.50*	<0.001
Delivery
Gestational age, weeks	39.19±1.48	39.31±1.46	39.24±1.46	39.19±1.40*	39.01±1.57*	0.878
Birth weight, g	3241.58±436.35	3210.68±420.10	3239.21±426.38*	3244.01±429.92*	3271.90±465.27*	<0.001
Cesarean section, n (%)	4506(37.2)	981(32.7)	1028(34.3)	1177(38.4)*	1320(43.3)*	<0.001
Sex of newborn, n (%)						0.008
Boys	6420(53.0)	1652(55.0)	1610(53.7)	1556(50.8)*	1602(52.6)
Girls	5688(47.0)	1349(45.0)	1387(46.3)	1508(49.2)*	1444(47.4)
GDM, n(%)						<0.001
Yes	1915(15.8)	253(8.4)	373(12.4)*	493(16.1)*	796(26.1)*
No	10,193(84.2)	2748(91.6)	2624(87.6)*	2571(83.9)*	2250(73.9)*

Notes: Date are presented as mean± standard deviation for continuous variables and n(%) for categorical variables. *Different from Q1 group.

Abbreviations: TyG, triglyceride-glucose; BMI, body mass index; FPG, fasting plasma glucose; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; TC, total cholesterol; TG, triglyceride.

Table 2 Association of Triglyceride-Glucose (TyG) Index with Large for Gestational Age (LGA)

	TyG (n=12,108)	Q1 (n=3001)	Q2 (n=2997)	Q3 (n=3064)	Q4 (n=3046)	P for trend
	OR (95% CI)	OR (95% CI)	OR (95% CI)	OR (95% CI)	OR (95% CI)
LGA (%)	1381(11.4)	233(7.8)	315(10.5)	346(11.3)	487(16.0)	<0.001
Unadjusted model	2.35(2.01,2.76)	1(Ref)	1.40(1.17,1.67)	1.51(1.27,1.80)	2.26(1.92,2.67)	<0.001
Model 1^a	1.62(1.37,1.92)	1(Ref)	1.29(1.09,1.54)	1.31(1.10,1.57)	1.65(1.39,1.96)	<0.001
Model 2^b	2.05(1.64,2.57)	1(Ref)	1.34(1.12,1.61)	1.36(1.13,1.64)	1.86(1.51,2.27)	<0.001

Notes: ^aModel 1: Adjusted for maternal age, education level, gravidity, parity, gestational age at delivery, prepregnancy BMI, and infant sex, smoking status; ^bModel 2: was further adjusted for first trimester diastolic blood pressure, first trimester high density lipoprotein cholesterol, first trimester low density lipoprotein cholesterol, and first trimester total cholesterol.

Abbreviations: LGA, large for gestational age; OR, odds ratio; CI, confidence interval.

Table 3 Stratification Analysis on the Association Between Triglyceride-Glucose (TyG) Index and Large for Gestational Age (LGA)

Subgroup	LGA (%)	TyG Quartile				P trend	P interaction
		Q1	Q2 OR (95% CI)^a	Q3 OR (95% CI)^a	Q4 OR (95% CI)^a
Advanced age							0.967
<35	1157(83.8)	1(Ref)	1.41(1.17,1.71)	1.53(1.27,1.85)	2.24(1.87,2.68)	<0.001
≥35	224(16.2)	1(Ref)	1.20(0.71,2.01)	1.19(0.73,1.94)	1.78(1.14,2.79)	0.021
Education level							0.815
College and above	1038(75.2)	1(Ref)	1.42(1.17,1.73)	1.53(1.26,1.86)	2.19(1.81,2.64)	<0.001
High school or equivalent	194(14.0)	1(Ref)	1.72(1.05,2.82)	1.37(0.83,2.28)	1.98(1.23,3.19)	0.027
Less than high school	149(10.8)	1(Ref)	0.66(0.33,1.33)	1.407(0.77,2.56)	2.45(1.43,4.20)	<0.001
Gravidity							0.683
1	434(31.4)	1(Ref)	1.63(1.23,2.16)	1.52(1.13,2.05)	2.40(1.80,3.21)	<0.001
2	443(32.1)	1(Ref)	1.22(0.89,1.68)	1.43(1.05,1.94)	1.66(1.23,2.23)	0.006
≥3	504(36.5)	1(Ref)	1.212(0.87,1.68)	1.278(0.94,1.75)	2.012(1.51,2.68)	<0.001
Parity							0.444
Primiparous	634(45.9)	1(Ref)	1.507(1.19,1.92)	1.57(1.23,2.00)	2.22(1.75,2.82)	<0.001
Multiparous	747(54.1)	1(Ref)	1.19(0.91,1.55)	1.25(0.97,1.61)	1.80(1.42,2.28)	<0.001
Infant sex							0.891
Girl	683(49.5)	1(Ref)	1.338(1.03,1.71)	1.34(1.05,1.72)	2.16(1.71,2.73)	<0.001
Boy	698(50.5)	1(Ref)	1.458(1.14,1.87)	1.684(1.32,2.15)	2.35(1.86,2.96)	<0.001
Smoking							0.536
Yes	36(2.6)	1(Ref)	5.31(1.13,25.04)	5.60(1.15,27.23)	8.71(1.88,40.34)	0.049
No	1345(97.4)	1(Ref)	1.36(1.14,1.63)	1.48(1.24,1.77)	2.209(1.87,2.61)	<0.001

Notes: ^aAdjusted for maternal age, education level, gravidity, parity, gestational age at delivery, prepregnancy BMI, and infant sex, smoking status, first trimester diastolic blood pressure, first trimester high density lipoprotein cholesterol, first trimester low density lipoprotein cholesterol, and first trimester total cholesterol.

Abbreviations: LGA, large for gestational age; OR, odds ratio; CI, confidence interval.

Table 4 Receiver Operating Characteristic (ROC) Analysis of the Triglyceride-Glucose (TyG) Index for Predicting Large for Gestational Age (LGA)

BMI Category	AUC (95% CI)	Threshold	Sensitivity	Specificity	P
All women	0.584(0.569,0.600)	8.34	0.74	0.38	<0.001
Underweight	0.563(0.508,0.618)	8.54	0.37	0.74	<0.001
Normal weight	0.568(0.549,0.587)	8.34	0.72	0.38	<0.001
Overweight	0.554(0.518,0.589)	8.69	0.51	0.59	<0.001

Abbreviations: AUC, areas under the curve; BMI, body mass index; CI, confidence interval.

Table 5 Association of Triglyceride-Glucose (TyG) Index with Large for Gestational Age (LGA)

	TyG	Q1	Q2	Q3	Q4
	OR (95% CI)^a	OR (95% CI)	OR (95% CI)^a	OR (95% CI)^a	OR (95% CI)^a
Excluding women with hyperthyroidism (n=201)	2.04(1.62,2.56)	1(Ref)	1.35(1.13,1.62)	1.35(1.12,1.63)	1.85(1.51,2.28)
Excluding women with hypothyroidism (n=405)	2.06(1.64,2.60)	1(Ref)	1.36(1.13,1.64)	1.37(1.13,1.66)	1.80(1.51,2.29)
Excluding women with hyperthyroidism and hypothyroidism (n=606)	2.05(1.63,2.59)	1(Ref)	1.38(1.14,1.66)	1.37(1.13,1.67)	1.87(1.51,2.31)
Excluding women with GDM (n=1915)	2.06(1.60,2.64)	1(Ref)	1.36(1.12,1.64)	1.39(1.14,1.69)	1.86(1.49,2.33)
Excluding women with hyperthyroidism, hypothyroidism and GDM	2.09(1.61,2.71)	1(Ref)	1.39(1.14,1.70)	1.41(1.15,1.73)	1.89(1.51,2.38)

Notes: ^aadjusted for maternal age, education level, gravidity, parity, gestational age at delivery, prepregnancy BMI, and infant sex, smoking status, first trimester diastolic blood pressure, first trimester high density lipoprotein cholesterol, first trimester low density lipoprotein cholesterol, and first trimester total cholesterol.

Abbreviations: OR, odds ratio; CI, confidence interval.