First-Trimester Triglyceride-Glucose Index and Risk of Pregnancy-Related Complications: A Prospective Birth Cohort Study in Southeast China

Figures & data

Table 1 Anthropometric and Biochemical Characteristics of the Participants According to Triglyceride-Glucose (TyG) Index Quintiles

Variables	Overall	TyG Index Quintiles					P value
	Total (n = 11,387)	Q1 (n = 2278)	Q2 (n = 2277)	Q3 (n = 2277)	Q4 (n = 2276)	Q5 (n = 2279)
Race-Han, n (%)	11,234 (98.7)	2238 (98.2)	2250 (98.8)	2246 (98.6)	2244 (98.6)	2256 (99)	0.029
Maternal age, years	30.0 ± 4.0	29.2 ± 3.7	29.5 ± 3.8	30.0 ± 3.9	30.3 ± 4.0	31.2 ± 4.1	< 0.001
Pre-pregnancy BMI, kg/m^2	21.1 ± 3.0	20.3 ± 2.6	20.6 ± 2.7	20.9 ± 2.7	21.4 ± 3.0	22.5 ± 3.2	< 0.001
Assisted reproduction, n (%)	603 (5.3)	67 (2.9)	84 (3.7)	106 (4.7)	147 (6.5)	199 (8.8)	< 0.001
Abortion history, n (%)	4173 (36.7)	695 (30.5)	760 (33.4)	809 (35.5)	914 (40.2)	995 (43.7)	< 0.001
Gravidity, n (%)							< 0.001
1	4902 (43.0)	1242 (54.5)	1108 (48.7)	1000 (43.9)	851 (37.4)	701 (30.8)
2	3423 (30.1)	564 (24.8)	645 (28.3)	681 (29.9)	759 (33.3)	774 (34)
3	1862 (16.4)	286 (12.6)	335 (14.7)	364 (16)	402 (17.7)	475 (20.8)
≥4	1200 (10.5)	186 (8.2)	189 (8.3)	232 (10.2)	264 (11.6)	329 (14.4)
Parity, n (%)							< 0.001
0	6646 (58.4)	1581 (69.4)	1457 (64)	1350 (59.3)	1217 (53.5)	1040 (45.6)
1	4278 (37.6)	632 (27.8)	731 (32.1)	837 (36.8)	964 (42.4)	1114 (48.9)
≥2	463 (4.0)	64 (2.8)	89 (3.9)	90 (4)	95 (4.2)	125 (5.5)
Gestational week at examination, weeks	11.3 ± 1.1	11.0 ± 1.2	11.2 ± 1.2	11.3 ± 1.1	11.4 ± 1.0	11.5 ± 1.1	< 0.001
SBP, mmHg	113.8 ± 10.9	111.6 ± 10.9	112.9 ± 10.7	113.5 ± 10.6	114.8 ± 11.1	116.1 ± 10.5	< 0.001
DBP, mmHg	68.6 ± 8.6	66.8 ± 8.5	67.9 ± 8.5	68.4 ± 8.4	69.4 ± 8.5	70.2 ± 8.5	< 0.001
FPG, mg/dl	85.7 ± 6.4	83.4 ± 6.1	84.8 ± 5.9	85.5 ± 5.9	86.4 ± 6.1	88.3 ± 7.0	< 0.001
TG, mg/dl	111.6 (90.3, 139.9)	75.3 (68.2, 81.5)	94.7 (89.4, 100.1)	111.6 (105.4, 117.8)	132.8 (124.0, 140.8)	174.4 (158.5, 201.9)	< 0.001
Total cholesterol, mg/dl	179.3 ± 28.3	166.4 ± 24.6	174.2 ± 25.7	179.2 ± 26.2	185.1 ± 27.6	191.4 ± 30.5	< 0.001
LDL-C, mg/dl	92.3 ± 23.3	81.9 ± 20.0	88.1 ± 20.8	92.2 ± 21.5	97.1 ± 22.9	102.1 ± 25.5	< 0.001
HDL-C, mg/dl	65.0 ± 11.8	67.0 ± 11.3	66.8 ± 11.7	65.8 ± 11.6	64.7 ± 11.4	60.6 ± 11.5	< 0.001
Hemoglobin, g/L	127.4 ± 9.7	125.9 ± 9.7	126.9 ± 9.5	127.4 ± 9.7	128.0 ± 9.5	129.0 ± 9.9	< 0.001
Uric acid, μmoI/L	232.0 (203.3, 265.0)	224.6 (197.6, 253.9)	227.4 (199.4, 260.5)	231.2 (203.3, 261.0)	232.7 (204.6, 268.1)	244.8 (213.0, 280.8)	< 0.001
Creatinine, μmoI/L	43.0 (38.9, 47.2)	42.8 (38.6, 47.0)	43.1 (39.0, 47.3)	43.0 (38.9, 47.1)	43.2 (39.0, 47.6)	43.1 (38.9, 47.2)	0.505
ALT, U/L	12.6 (9.7, 17.9)	11.9 (9.5, 16.2)	12.2 (9.5, 16.9)	12.3 (9.5, 17.4)	12.9 (9.9, 18.9)	13.9 (10.4, 20.5)	< 0.001
AST, U/L	16.4 (14.3, 19.1)	16.4 (14.3, 18.9)	16.3 (14.3, 18.9)	16.3 (14.2, 18.9)	16.4 (14.3, 19.4)	16.5 (14.2, 19.6)	0.345
Delivery gestations, weeks	39.2 ± 1.5	39.3 ± 1.5	39.2 ± 1.6	39.2 ± 1.4	39.2 ± 1.5	39.0 ± 1.6	< 0.001
Gestational weight gain, kg	13.5 ± 5.0	14.3 ± 4.6	14.0 ± 4.5	13.6 ± 4.7	13.3 ± 5.3	12.4 ± 5.5	< 0.001
Gestational weight gain, n (%)							< 0.001
<recommendation	3634 (32.3)	618 (27.4)	621 (27.6)	747 (33.2)	768 (34.2)	880 (39.3)
Within recommendation	4415 (39.3)	916 (40.7)	955 (42.5)	873 (38.8)	867 (38.6)	804 (35.9)
>recommendation	3187 (28.4)	719 (31.9)	672 (29.9)	631 (28)	612 (27.2)	553 (24.7)

Note: Data are presented as mean ± standard deviation, median (interquartile range) or n (%).

Abbreviations: ALT, alanine aminotransferase; AST, aspartate aminotransferase; DBP, diastolic blood pressure; HDL-C, high density lipoprotein cholesterol; LDL-C, low density lipoprotein cholesterol; SBP, systolic blood pressure; TC, total cholesterol.

Figure 1 The risk of pregnancy-related complications with increasing triglyceride-glucose (TyG) index. The solid line represents adjusted probability and shadow parts 95% confidence intervals. Adjusted for race, pre-pregnancy BMI, maternal age, assisted reproduction, abortion history, gravidity, parity, gestational weight gain, delivery gestations, gestational week at the examination, systolic blood pressure, diastolic blood pressure, total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, hemoglobin, uric acid, creatinine, alanine aminotransferase, and aspartate aminotransferase. (A), Gestational diabetes mellitus; (B), Gestational hypertension; (C), Preeclampsia; (D), Placental abruption; (E), Fetal distress; (F), Premature rupture of membranes.

Table 2 Association of Triglyceride-Glucose (TyG) Index with Gestational Diabetes Mellitus (GDM)

Predictor	Number	GDM, n (%)	Crude	P value	Model 1^a	P value	Model 2^b	P value
			OR (95% CI)		OR (95% CI)		OR (95% CI)
TyG index, per unit	11,387	2787 (24.5)	4.31 (3.79~4.90)	<0.001	3.12 (2.72~3.59)	<0.001	3.49 (2.87~4.25)	<0.001
TyG index, per SD	11387	2787 (24.5)	1.66 (1.59~1.73)	<0.001	1.48 (1.41~1.56)	<0.001	1.54 (1.44~1.65)	<0.001
TyG index Quintile 1	2278	335 (14.7)	1 (Ref)		1 (Ref)		1 (Ref)
Quintile 2	2275	410 (18.0)	1.28 (1.09~1.49)	0.003	1.22 (1.04~1.44)	0.015	1.20 (1.02~1.41)	0.031
Quintile 3	2279	506 (22.2)	1.66 (1.42~1.93)	<0.001	1.46 (1.25~1.71)	<0.001	1.41 (1.20~1.66)	<0.001
Quintile 4	2276	637 (28.0)	2.25 (1.94~2.61)	<0.001	1.90 (1.63~2.22)	<0.001	1.81 (1.54~2.14)	<0.001
Quintile 5	2279	899 (39.4)	3.78 (3.27~4.36)	<0.001	2.74 (2.35~3.19)	<0.001	2.52 (2.09~3.05)	<0.001
Trend test				<0.001		<0.001		<0.001

Notes: ^aModel 1 adjusted for race, pre-pregnancy BMI, maternal age, assisted reproduction, abortion history, gravidity, parity, delivery gestations, and gestational weight gain; ^bModel 2 further adjusted for gestational week at the examination, systolic blood pressure, diastolic blood pressure, total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, hemoglobin, uric acid, creatinine, alanine aminotransferase, and aspartate aminotransferase. The bolded P value indicates statistical significance.

Figure 2 Subgroup analysis of the association between triglyceride-glucose (TyG) index and risk of gestational diabetes mellitus (GDM). Models adjusted for race, pre-pregnancy BMI, maternal age, assisted reproduction, abortion history, gravidity, parity, gestational weight gain, delivery gestations, gestational week at the examination, systolic blood pressure, diastolic blood pressure, total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, hemoglobin, uric acid, creatinine, alanine aminotransferase, and aspartate aminotransferase (not for adjusted variables stratified analysis).

Table 3 Association of Triglyceride-Glucose (TyG) Index with Other Pregnancy-Related Complications

Predictor	Number	Pregnancy-Related Complications, n (%)	Crude	P value	Model 1^a	P value	Model 2^b	P value
			OR (95% CI)		OR (95% CI)		OR (95% CI)
Gestational hypertension	11,387	387 (3.4)	2.06 (1.56~2.73)	<0.001	1.86 (1.38~2.5)	<0.001	1.07 (0.7~1.66)	0.746
Preeclampsia	11,387	196 (1.7)	1.84 (1.25~2.73)	0.002	1.26 (0.83~1.9)	0.281	0.56 (0.30~1.01)	0.054
Placental abruption	11,387	257 (2.3)	1.16 (0.82~1.66)	0.399	1.20 (0.82~1.77)	0.341	1.33 (0.78~2.29)	0.294
Fetal distress	11,387	2152 (18.9)	0.97 (0.84~1.11)	0.631	1.12 (0.97~1.29)	0.127	1.04 (0.85~1.27)	0.721
Premature rupture of membranes	11,387	3014 (26.5)	0.84 (0.74~0.95)	0.005	0.98 (0.86~1.12)	0.797	1.05 (0.88~1.26)	0.609

Notes: ^aModel 1 adjusted for race, pre-pregnancy BMI, maternal age, assisted reproduction, abortion history, gravidity, parity, delivery gestations, and gestational weight gain; ^bModel 2 further adjusted for gestational week at the examination, systolic blood pressure, diastolic blood pressure, total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol, hemoglobin, uric acid, creatinine, alanine aminotransferase, and aspartate aminotransferase. The bolded P value indicates statistical significance.

Table 4 ROC Analysis of the Triglyceride-Glucose (TyG) Index for Detecting Pregnancy-Related Complications

Predictor	AUC (95% CI), %	Threshold	Sensitivity	Specificity	PPV	NPV	Accuracy	Precision
Gestational diabetes mellitus	63.74 (62.55~64.93)	8.549	0.553	0.649	0.338	0.817	0.625	0.338
Gestational hypertension	56.41 (53.36~59.46)	8.547	0.512	0.601	0.043	0.972	0.598	0.043
Preeclampsia	56.19 (51.87~60.52)	8.560	0.515	0.614	0.023	0.986	0.613	0.023
Placental abruption	51.24 (47.65~54.83)	8.680	0.300	0.732	0.025	0.978	0.722	0.025
Fetal distress	50.36 (48.99~51.73)	8.411	0.448	0.568	0.194	0.815	0.545	0.194
Premature rupture of membranes	51.82 (50.62~53.02)	8.574	0.652	0.381	0.275	0.753	0.453	0.275

Note: The bolded AUC (95% CI) indicates statistical significance.

Abbreviations: AUC: area under curve; PPV positive predictive value; NPV, negative predictive value.