Low-molecular-weight dextran for optical coherence tomography may not be protective against kidney injury in patients with renal insufficiency

Table 1 Patients’ characteristics and renal function (entire study cohort)

	Total (n = 421)	Control (n = 342)	LMWD (n = 79)	P value
Sex
Male	281 (66.7)	219 (64.0)	62 (78.5)	0.017
Female	140 (33.3)	123 (36.0)	17 (21.5)
Age, yr	75.0 [69.0, 80.0]	76.0 [69.0, 80.0]	74.0 [68.0, 79.0]	0.178
Body mass index, kg/m2	24.0 [21.1, 26.2]	23.9 [21.1, 26.0]	24.4 [21.3, 26.6]	0.273
Procedure
Coronary angiography	279 (66.3)	238 (69.6)	41 (51.9)	0.004
PCI	142 (33.7)	104 (30.4)	38 (48.1)
Diagnosis
Stable CAD	350 (83.1)	288 (84.2)	62 (78.5)	0.243
Acute coronary syndrome	71 (16.9)	54 (15.8)	17 (21.5)
Prior myocardial infarction	155 (36.8)	106 (31.0)	49 (62.0)	< 0.001
Prior PCI	209 (49.6)	148 (43.3)	61 (77.2)	< 0.001
Prior CABG	22 (5.2)	20 (5.8)	2 (2.5)	0.397
Hypertension	266 (63.2)	210 (61.4)	56 (70.9)	0.122
Dyslipidemia	178 (42.3)	140 (40.9)	38 (48.1)	0.257
Diabetes mellitus	218 (51.8)	172 (50.3)	46 (58.2)	0.214
Stroke	21 (5.0)	20 (5.8)	1 (1.3)	0.147
Current smoking	56 (13.3)	35 (10.2)	21 (26.6)	< 0.001
Serum creatinine, mg/dL	1.33 [1.22, 1.56]	1.33 [1.20, 1.52]	1.36 [1.27, 1.62]	0.057
eGFR, mL/min/1.73 m2	38.4 [32.9, 42.3]	38.5 [32.6, 42.4]	36.9 [33.1, 41.8]	0.368
GFR category
3b (30 ≤ eGFR < 45)	352 (83.6)	284 (83.0)	68 (86.1)	0.783
4 (15 ≤ eGFR < 30)	64 (15.2)	54 (15.8)	10 (12.6)
5 (eGFR < 15)	5 (1.2)	4 (1.2)	1 (1.3)
Hemoglobin A1c, %	6.3 [5.8, 6.9]	6.3 [5.7, 7.0]	6.4 [6.0, 6.9]	0.109
Low-density lipoprotein cholesterol, mg/dL	86 [71, 107]	87 [72, 108]	82 [70, 103]	0.301
Hemoglobin, g/dL	11.8 [10.5, 13.4]	11.8 [10.5, 13.4]	12.1 [10.9, 13.5]	0.375
C-reactive protein, mg/dL	0.14 [0.05, 0.42]	0.13 [0.05, 0.40]	0.15 [0.06, 0.53]	0.180
NT-proBNP, pg/mL	864.5 [279.8, 3471.3]	991.0 [288.3, 3700.0]	633.0 [177.3, 1775.5]	0.099
LVEF, %	57 [44, 66]	58 [44, 66]	52 [43, 63]	0.140
Mehran risk score	8 [6, 11]	8 [6, 11]	8 [7, 11]	0.710
Catheterization procedure
Total agent volume, mL	150.0 [103.0, 226.0]	133.0 [92.0, 192.3]	207.0 [167.5, 271.8]	< 0.001
Total contrast volume, mL	135.0 [95.0, 193.0]	133.0 [92.0, 192.3]	140.0 [102.0, 195.0]	0.618
LMWD volume, mL	0.0 [0.0, 0.0]	0.0 [0.0, 0.0]	67.6 [43.3, 86.0]	< 0.001
OCT	79 (40.6)	92 (26.9)	79 (100.0)	< 0.001
Renal function post-procedure
ΔCre within 5 d, mg/dL	−0.01 [-0.11, 0.13]	0.00 [-0.10, 0.14]	−0.03 [-0.14, 0.12]	0.414
ΔCre at 1 mo, mg/dL	−0.01 [-0.15, 0.11]	-0.01 [-0.16, 0.11]	-0.01 [-0.13, 0.09]	0.686
ΔCre at 1 yr, mg/dL	0.01 [-0.13, 0.18]	0.00 [-0.14, 0.16]	0.07 [-0.04, 0.34]	0.004
Acute kidney injury	51 (12.1)	42 (12.3)	9 (11.4)	1.000
Worsening renal function (ΔCre ≥ 0.3 mg/dL/1 yr)	80 (19.0)	58 (17.0)	22 (27.8)	0.039

Data are presented as n (%) or median (25^th-75^th percentile). CABG: Coronary artery bypass graft surgery; CAD: Coronary artery disease; ΔCre: Delta creatinine; eGFR: Estimated glomerular filtration rate; LMWD: Low-molecular-weight dextran; LVEF: Left ventricular ejection fraction; NT-proBNP: N-terminal pro B-type natriuretic peptide; OCT: Optical coherence tomography; PCI: Percutaneous coronary intervention.

Table 2 Patients’ characteristics and renal function (matched cohort)

	Total (n = 150)	Control (n = 75)	LMWD (n = 75)	P value
Sex
Male	119 (79.3)	61 (81.3)	58 (77.3)	0.687
Female	31 (20.7)	14 (18.7)	17 (22.7)
Age, yr	75.0 [67.5, 80.0]	75.0 [69.0, 80.0]	74.0 [67.0, 79.5]	0.643
Body mass index, kg/m2	23.7 [21.0, 25.9]	23.0 [20.8, 25.4]	24.5 [21.3, 26.8]	0.030
Procedure
Coronary angiography	84 (56.0)	43 (57.3)	41 (54.7)	0.869
PCI	66 (44.0)	32 (42.7)	34 (45.3)
Diagnosis
Stable CAD	121 (80.7)	61 (81.3)	60 (80.0)	1.000
Acute coronary syndrome	29 (19.3)	14 (18.7)	15 (20.0)
Prior myocardial infarction	77 (51.3)	30 (40.0)	47 (62.7)	0.009
Prior PCI	93 (62.0)	34 (45.3)	59 (78.7)	< 0.001
Prior CABG	4 (2.7)	2 (2.7)	2 (2.7)	1.000
Hypertension	98 (65.3)	45 (60.0)	53 (70.7)	0.230
Dyslipidemia	63 (42.0)	28 (37.3)	35 (46.7)	0.321
Diabetes mellitus	81 (54.0)	37 (49.3)	44 (58.7)	0.326
Stroke	5 (3.3)	4 (5.3)	1 (1.3)	0.367
Current smoking	29 (19.3)	9 (12.0)	20 (26.7)	0.037
Serum creatinine, mg/dL	1.36 [1.25, 1.63]	1.37 [1.26, 1.71]	1.35 [1.25, 1.61]	0.612
eGFR, mL/min/1.73 m2	37.6 [32.8, 42.0]	38.0 [31.0, 42.2]	37.0 [33.2, 41.8]	0.949
GFR category
3b (30 ≤ eGFR < 45)	125 (83.3)	59 (78.7)	66 (88.0)	0.189
4 (15 ≤ eGFR < 30)	25 (16.7)	16 (21.3)	9 (12.0)
5 (eGFR < 15)	0 (0.0)	0 (0.0)	0 (0.0)
Hemoglobin A1c, %	6.3 [5.9, 6.9]	6.1 [5.7, 6.9]	6.5 [6.0, 7.0]	0.058
Low-density lipoprotein cholesterol, mg/dL	87 [70, 108]	88 [72, 114]	81 [70, 103]	0.155
Hemoglobin, g/dL	11.8 [10.5, 13.4]	11.5 [10.3, 13.5]	12.1 [10.9, 13.3]	0.230
C-reactive protein, mg/dL	0.14 [0.05, 0.46]	0.12 [0.05, 0.35]	0.15 [0.06, 0.53]	0.320
NT-proBNP, pg/mL	835.5 [244.8, 3265.3]	1560.0 [270.0, 4268.5]	632.0 [175.0, 1679.5]	0.076
LVEF, %	53 [43, 64]	56 [44, 64]	52 [43, 63]	0.697
Mehran risk score	8 [7, 11]	8 [7, 11]	8 [7, 11]	0.548
Catheterization procedure
Total agent volume, mL	174.1 [120.0, 244.8]	130.0 [88.0, 196.5]	209.7 [170.1, 271.8]	< 0.001
Total contrast volume, mL	138.0 [97.5, 200.0]	130.0 [88.0, 196.5]	142.0 [104.5, 200.0]	0.408
LMWD volume, mL	7.6 [0.0, 68.2]	0.0 [0.0, 0.0]	68.5 [43.9, 86.0]	< 0.001
OCT	95 (63.3)	20 (26.7)	75 (100.0)	< 0.001
Renal function post-procedure
ΔCre within 5 d, mg/dL	-0.03 [-0.15, 0.13]	-0.04 [-0.15, 0.14]	-0.03 [-0.14, 0.10]	0.848
ΔCre at 1 mo, mg/dL	-0.03 [-0.17, 0.09]	-0.06 [-0.23, 0.10]	-0.02 [-0.14, 0.08]	0.276
ΔCre at 1 yr, mg/dL	0.01 [-0.14, 0.19]	-0.04 [-0.23, 0.08]	0.06 [-0.06, 0.29]	0.001
Acute kidney injury	14 (9.3)	7 (9.3)	7 (9.3)	1.000
Worsening renal function (ΔCre ≥ 0.3 mg/dL/1 yr)	28 (18.7)	9 (12.0)	19 (25.3)	0.059

Data are presented as n (%) or median (25^th-75^th percentile). CABG: Coronary artery bypass graft surgery; CAD: Coronary artery disease; ΔCre: Delta creatinine; eGFR: Estimated glomerular filtration rate; LMWD: Low-molecular-weight dextran; LVEF: Left ventricular ejection fraction; NT-proBNP: N-terminal pro B-type natriuretic peptide; OCT: Optical coherence tomography; PCI: Percutaneous coronary intervention.

Table 3 Univariable and multivariable logistic regression model for predicting worsening renal function (ΔCre ≥ 0.3 mg/dL/1-year) in matched cohort

Variable	Univariable				Multivariable
	OR	95%CI lower limit	95%CI upper limit	P value	OR	95%CI lower limit	95%CI upper limit	P value
Female	1.72	0.68	4.39	0.256
Age	0.96	0.92	0.99	0.036				Not selected
Body mass index, kg/m2	1.02	0.92	1.13	0.759
PCI	1.61	0.70	3.67	0.260
Acute coronary syndrome	1.92	0.75	4.95	0.175
Prior myocardial infarction	1.33	0.58	3.05	0.496
Prior PCI	1.68	0.69	4.11	0.258
Hypertension	0.95	0.40	2.23	0.897
Diabetes mellitus	2.04	0.86	4.87	0.107
Stroke	1.09	0.12	10.20	0.938
Current smoking	1.17	0.43	3.22	0.756
eGFR < 38.4 mL/min/1.73 m2	4.18	1.58	11.00	0.004	4.27	1.59	11.40	0.004
LVEF, %	0.98	0.95	1.01	0.220
Mehran risk score	1.07	0.98	1.17	0.127
Total agent volume, mL	1.00	0.99	1.01	0.533
Total contrast volume, mL	0.99	0.99	1.01	0.776
LMWD volume ≥ 52 mL	2.76	1.19	6.37	0.018	2.83	1.18	6.76	0.019

CI: Confidence interval; eGFR: Estimated glomerular filtration rate; LMWD: Low-molecular-weight dextran; LVEF: Left ventricular ejection fraction; OR: Odds ratio; PCI: Percutaneous coronary intervention.