An Uninvestigated Risk Factor for Contrast-Induced Nephropathy in Chronic Kidney Disease: Proteinuria

Figures & data

Table 1. Baseline demographic and clinical characteristics of the patients.

Variable	Patients (n = 70) (%)
Age > 75 years	5 (6.1)
Diabetes	30 (42.9)
Hypertension	62 (88.6)
Coronary heart disease	38 (54.3)
Heart failure	10 (14.3)
Anemia	25 (35.71)
sCr (mg/dL)	1.43 (±0.77)
<1.5	47 (67.8)
≥1.5	23 (32.2)
eGFR (mL/min/1.73 m^2)	59.27 (±26.61)
≥60	32 (46.5)
<60	38 (53.5)
Salb (g/dL)	3.70 (±0.63)
≥3.5	46 (65.7)
<3.5	24 (34.3)
Proteinuria (g/day)	585 (2,731,173)
<1	45 (64.2)
≥1	25 (35.8)
Volume of the contrast media (mL)	108 (±28)
<100	42 (60)
≥100	28 (40)

Note: sCr, serum creatinine; eGFR, estimated glomerular filtration rate; Salb, serum albumin.

Table 2. Univariate analysis of the variables associated with CIN.

Variable	CIN (+) (n = 26) (37.1%)	CIN (−) (n = 44) (62.9%)	p
Advanced age	3 (11.53)	2 (4.54)	<0.05
Diabetes	16 (61.53)	14 (31.81)	<0.05
Hypertension	23 (88.5)	39 (88.63)	0.63
Coronary heart disease	16 (61.5)	22 (50)	0.34
Heart failure	7 (26.9)	3 (6.81)	<0.05
Anemia	18 (69.23)	7 (15.90)	<0.05
sCr ≥1.5 mg/dL	15 (57.69)	8 (18.18)	<0.01
eGFR <60 mL/min/1.73 m^2	21 (80.76)	17 (38.63)	<0.01
Salb <3.5 g/dL	13 (50)	11 (25)	<0.05
Proteinuria ≥1 g/day	16 (61.5)	9 (20.45)	<0.01
Contrast media ≥100 mL	19 (73.1)	9 (20.45)	<0.01

Note: CIN, contrast-induced nephropathy; sCr, serum creatinine; eGFR, estimated glomerular filtration rate; Salb, serum albumin.

Table 3. Relationship between urinary protein excretion and CIN in patients with eGFR <60 mL/min/1.73m².

	Proteinuria ≥1 g/day (n = 19) (%)	Proteinuria <1 g/day (n = 20) (%)	p
CIN	15 (78.9)	6 (40)	<0.05
Mean eGFR	36.36	41.20	0.23
Mean Salb	3.18	3.88	<0.05

Note: eGFR, estimated glomerular filtration rate (mL/min/1.73 m²); Salb, serum albumin (g/dL); CIN, contrast-induced nephropathy.

Figure 1. Relationship between proteinuria and the development of CIN.