Relationship between the triglyceride–glucose index and coronary artery calcification in asymptomatic, non-diabetic patients undergoing maintenance hemodialysis

Figures & data

Figure 1. Enrollment flowchart for this study. HD: hemodialysis.

Table 1. Clinical characteristics of the participants according to TyG index tertiles.

	Total	TyG index			p Value
		Tertile 1 (7.32–8.33)	Tertile 2 (8.34–8.81)	Tertile 3 (8.82–10.32)
Number of participants, (n)	151	50	50	51	–
Sex (male/female), (n)	84/67	30/20	25/25	29/22	0.589
Age, (y)	56.66 ± 12.43	56.80 ± 12.62	56.38 ± 12.82	56.78 ± 12.10	0.982
BMI, (kg/m^2)	22.70 ± 3.75	22.13 ± 3.32	22.04 ± 3.02	23.91 ± 4.49	0.017
Smoking, n (%)	30 (19.87%)	7 (14.00%)	11 (22.00%)	12 (23.53%)	0.437
Alcohol consumption, n (%)	28 (18.54%)	10 (20.00%)	11 (22.00%)	7 (13.73%)	0.535
Hypertension, n (%)	120 (79.47%)	41 (82.00%)	43 (86.00%)	36 (70.59%)	0.137
SBP, (mmHg)	144.77 ± 23.15	149.76 ± 21.67	139.24 ± 22.49	145.31 ± 24.41	0.073
DBP, (mmHg)	80.70 ± 11.48	84.48 ± 10.63	77.54 ± 10.07	80.08 ± 12.69	0.009
Fasting plasma glucose, (mmol/L)	4.70 (4.20–5.10)	4.55 (4.00–4.83)	4.55 (4.20–5.10)	4.90 (4.30–5.90)	0.004
Triglyceride, (mmol/L)	1.39 (0.95–2.13)	0.82 (0.62–1.03)	1.39 (1.24–1.58)	2.41 (2.12–3.08)	<0.001
TyG index	8.55 (8.17–9.03)	8.04 (7.72–8.18)	8.53 (8.42–8.70)	9.14 (9.02–9.49)	<0.001
Total cholesterol, (mmol/L)	4.33 ± 1.04	4.08 ± 0.92	4.50 ± 1.11	4.40 ± 1.05	0.110
HDL-C, (mmol/L)	1.09 (0.91–1.32)	1.26 (0.98–1.44)	1.09 (0.87–1.31)	1.00 (0.84–1.10)	<0.001
LDL-C, (mmol/L)	2.13 ± 0.74	1.89 ± 0.60	2.28 ± 0.77	2.20 ± 0.78	0.021
Hemoglobin, (g/L)	104.15 ± 18.31	103.64 ± 15.93	103.80 ± 19.19	104.98 ± 19.87	0.923
Albumin, (g/L)	41.90 (39.60–44.60)	41.90 (39.10–44.93)	41.75 (39.75–44.13)	42.10 (39.60–44.60)	0.852
Alkaline phosphatase, (U/L)	73.20 (57.00–94.00)	66.50 (54.75–81.00)	76.50 (59.50–103.00)	78.00 (60.00–98.00)	0.068
25(OH)D3, (ng/ml)	29.31 ± 11.65	30.47 ± 11.48	28.81 ± 12.31	28.67 ± 11.29	0.693
Calcium, (mmol/L)	2.18 (2.08–2.31)	2.17 (2.08–2.27)	2.17 (2.03–2.30)	2.26 (2.09–2.38)	0.174
Phosphorus, (mmol/L)	1.98 ± 0.58	1.84 ± 0.51	1.91 ± 0.53	2.17 ± 0.65	0.012
UA, (μmol/L)	421.00 (372.00–484.00)	407.50 (366.75–447.50)	415.00 (372.25–490.50)	443.00 (401.00–502.00)	0.071
CRP, (mg/L)	0.81 (0.50–5.08)	0.50 (0.50–1.28)	1.03 (0.50–7.63)	2.52 (0.50–7.06)	<0.001
Ferritin, (ng/ml)	97.69 (48.90–231.65)	141.49 (46.84–272.49)	85.49 (48.68–220.07)	95.70 (47.45–146.38)	0.399
PTH, (pg/mL)	221.40 (108.40–392.00)	203.25 (79.03–333.23)	168.65 (99.33–377.55)	336.00 (166.50–445.80)	0.013
Phosphorus binder therapy, n (%)	14 (9.27%)	3 (6.00%)	3 (6.00%)	8 (15.69%)	0.152
Duration of dialysis, (month)	49.00 (21.00–99.00)	42.00 (22.00–77.25)	41.00 (17.75–78.75)	67.00 (35.00–121.00)	0.032
Kt/V	1.26 ± 0.04	1.27 ± 0.04	1.26 ± 0.03	1.26 ± 0.03	0.087
Presence of CAC, n (%)	127 (84.11%)	36 (72.00%)	44 (88.00%)	47 (92.16%)	0.016
CACS	302.20 (29.60–976.32)	66.53 (0–469.18)	247.76 (37.35–827.61)	666.58 (165.10–2523.46)	<0.001

BMI: body mass index; SBP: systolic blood pressure; DBP: diastolic blood pressure; HDL-C: high-density lipoprotein cholesterol; LDL-C: low-density lipoprotein cholesterol; UA: uric acid; CRP: C-reactive protein; PTH: parathyroid hormone; Kt/v: fractional clearance index for urea; CAC: coronary artery calcification; CACS: coronary artery calcification score.

Table 2. Correlations between the CACS and risk factors.

	r	p Value
Sex	−0.105	0.200
Age	0.282	<0.001
BMI	0.051	0.531
Duration of dialysis	0.410	<0.001
Hemoglobin	−0.119	0.146
Albumin	−0.277	0.001
TyG index	0.414	<0.001
HDL-C	−0.175	0.032
Alkaline phosphatase	0.092	0.262
25(OH)D3	−0.106	0.193
Calcium	0.038	0.640
Phosphorus	0.007	0.936
UA	−0.010	0.907
CRP	0.372	<0.001
Ferritin	0.059	0.469
PTH	0.106	0.196

BMI: body mass index; HDL-C: high-density lipoprotein cholesterol; LDL-C: low-density lipoprotein cholesterol; UA: uric acid; CRP: C-reactive protein; PTH: parathyroid hormone; CACS: coronary artery calcification score.

Bold values are statistically significant at p < 0.05.

Table 3. Poisson regression analysis of CAC with the TyG index.

Variables	Crude PR (CI 95%)	P-value	Adjusted PR (CI 95%)	p Value
Age
≥60	2.732(2.499–2.986)	<0.001	1.136(1.031–1.253)	0.010
<60	–	–	–	–
Sex
male	1.046(0.923–1.184)	0.483
female	–	–
BMI
≥25	1.021(0.886–1.177)	0.772
<25	–	–
Smoking
yes	1.048(0.914–1.202)	0.499
no	–	–
Alcohol consumption
yes	1.049(0.907–1.215)	0.518
on	–	–
Hypertension
yes	1.081(0.907–1.289)	0.384
no	–	–
Phosphorus binder therapy
yes	1.098(0.901–1.338)	0.353
on	–	–
TyG index
tertile 1	–	–	–	–
tertile 2	1.230(1.042–1.451)	0.015	1.164(1.015–1.333)	0.029
tertile 3	1.398(1.199–1.630)	<0.001	1.281(1.121–1.465)	<0.001
Dialysis duration	2.453(2.224–2.706)	<0.001	1.002(1.001–1.003)	<0.001
Calcium	0.990(0.989–0.991)	<0.001	0.993(0.992–0.995)	<0.001
Phosphorus	1.010(0.911–1.119)	0.853
HDL-C	0.813(0.664–0.996)	0.046	1.010(0.849–1.201)	0.914
Albumin	0.973(0.961–0.985)	<0.001	0.983(0.969–0.997)	0.020
UA	1.000(0.999–1.001)	0.701
CRP	1.018(1.012–1.025)	<0.001	1.010(1.004–1.016)	0.002

PR: prevalence ratio; CI: confidence interval; BMI: body mass index; HDL-C: high-density lipoprotein cholesterol; UA: uric acid; CRP: C-reactive protein.

Figure 2. The CACS was grouped according to the TyG index tertiles. CACS: coronary artery calcification score. *<0.05; **<0.01; ***<0.001.

Figure 3. ROC curves of the TyG index (AUC = 0.667). ROC: receiver operating characteristic; AUC: area under the curve.

Data availability statement

The data analyzed in this study are available from the corresponding author upon reasonable request.