Prognostic Nutritional Index (PNI) as a Predictor in Patients with Metabolic Syndrome and Heart Failure

Figures & data

Table 1 Baseline Characteristics of Patients According to PNI

Variables	Nonmalnutrition (PNI≥45, n=535)	Mild malnutrition (40≤PNI<45, n=292)	Malnutrition (PNI<40, n=221)	P
Age, years	64±10	67±9	66±10	<0.001
Male, n (%)	402(75.1)	197(67.5)	169(76.5)	0.028
Smoking, n (%)	226(42.2)	108(37.0)	90(40.7)	0.337
Drinking, n (%)	156(29.2)	73(25.1)	55(24.9)	0.318
Previous MI, n (%)	184(34.4)	98(33.6)	60(27.1)	0.143
Previous stroke, n (%)	68(12.7)	35(12.0)	24(10.9)	0.775
BMI, kg/m^2	27.47±4.06	26.71±4.01	26.17±3.78	<0.001
Waist circumference, cm	100.3±12.1	98.2±11.7	97.6±11.0	0.005
NYHA class				<0.001
I/II	122(22.8)	52(17.8)	21(9.5)
III	344(64.3)	165(56.5)	105(47.5)
IV	69(12.9)	75(25.7)	95(43.0)
SBP, mmHg	126±19	126±20	129±22	0.350
DBP, mmHg	76±13	75±12	76±13	0.331
WBC, (10^9/L)	7.60(6.27, 8.94)	7.33(5.91, 8.73)	7.10(5.75, 9.56)	0.277
NEUT, (10^9/L)	4.61(3.62, 5.71)	4.98(3.82, 6.12)	5.08(3.87, 7.27)	<0.001
LYM, (10^9/L)	2.01(1.59, 2.48)	1.45(1.16, 1.80)	1.10(0.81, 1.40)	<0.001
MONO, (10^9/L)	0.56(0.45, 0.70)	0.57(0.45, 0.71)	0.58(0.44, 0.73)	0.794
FPG, (mg/dL)	135.36(103.50, 200.70)	143.73(106.07, 208.80)	154.98(110.70, 241.02)	0.029
TG, (mg/dL)	131.13(96.57, 185.17)	108.09(80.63, 152.39)	106.32(80.63, 147.08)	<0.001
TC, (mg/dL)	134.29(107.20, 162.93)	126.55(103.81, 150.54)	121.13(102.94, 155.19)	0.003
HDL-C, (mg/dL)	34.06(28.64, 39.86)	32.70(26.70, 37.93)	29.41(23.99, 37.15)	<0.001
LDL-C, (mg/dL)	85.14(63.86, 109.91)	81.27(63.95, 100.91)	78.95(61.15, 102.94)	0.154
eGFR, (mL/min/1.73 m^2)	79.60(59.11, 104.88)	67.68(46.52, 89.17)	54.40(33.78, 81.42)	<0.001
ALB, (g/L)	40.40(38.00, 42.35)	35.12(33.55, 36.69)	30.50(27.40, 32.60)	<0.001
LVEF, (%)	42(37, 47)	42(37, 48)	43(37, 49)	0.731
BNP, (pg/mL)	1881.00(635.85, 4433.50)	3454.53(1190.00, 7515.00)	4498.00(1727.00, 10023.00)	<0.001

Abbreviations: PNI, prognostic nutritional index; MI, myocardial infarction; BMI, body mass index; NYHA, New York Heart Association; SBP, systolic blood pressure; DBP, diastolic blood pressure; WBC, white blood cell count; NEUT, neutrophil count; LYM, lymphocyte count; MONO, monocyte count; FPG, fasting plasma glucose; TG, triglyceride; TC, total cholesterol; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; eGFR, estimated glomerular filtration rate; ALB, serum albumin; LVEF, left ventricular ejection fraction; BNP, brain natriuretic peptide.

Figure 1 Flow chart of study participant screening.

Table 2 Univariate and Multivariate Linear Regression Analysis for PNI

Variable	Univariate			Multivariate
	β	Standard β	P	β	Standard β	P
Age	−0.105	−4.735	<0.001	0.030	0.041	0.231
Male	0.255	0.016	0.613
Smoking	0.902	0.061	0.047	−0.171	−0.303	0.762
Drinking	1.152	0.071	0.022	0.655	0.040	0.285
Previous MI	0.981	0.064	0.039	0.833	0.054	0.055
Previous stroke	0.705	0.032	0.302
BMI	0.264	0.147	<0.001	−0.024	−0.013	0.667
NYHA class	−3.145	−0.286	<0.001	−2.003	−0.182	<0.001
TG	0.015	0.203	<0.001	0.012	0.174	<0.001
HDL-C	0.123	0.173	<0.001	0.130	0.182	<0.001
LDL-C	0.015	0.08	0.010	−0.006	−0.030	0.333
eGFR	0.059	0.308	<0.001	0.056	0.289	<0.001
LVEF	0.045	0.024	0.436

Abbreviations: PNI, Prognostic nutritional index; MI, myocardial infarction; BMI, body Mass Index; NYHA, New York Heart Association functional; TG, triglyceride; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; eGFR, estimated glomerular filtration rate; LVEF, left ventricular ejection fraction.

Table 3 Unadjusted and Adjusted Cox Regression Analyses for Adverse Outcomes

	Nonmalnutrition	Mild Malnutrition	P	Malnutrition	P
		HR (95% CI)		HR (95% CI)
All-cause death
Unadjusted	Reference	1.311(1.091–1.577)	0.004	1.728(1.427–2.093)	<0.001
Model1	Reference	1.299(1.079–1.564)	0.006	1.732(1.430–2.099)	<0.001
Model2	Reference	1.296(1.076–1.562)	0.006	1.722(1.420–2.088)	<0.001
Model3	Reference	1.311(1.086–1.583)	0.005	1.787(1.451–2.201)	<0.001
Cardiovascular death
Unadjusted	Reference	1.320(1.080–1.614)	0.007	1.753(1.426–2.155)	<0.001
Model1	Reference	1.330(1.086–1.629)	0.006	1.771(1.439–2.179)	<0.001
Model2	Reference	1.327(1.083–1.627)	0.006	1.776(1.443–2.187)	<0.001
Model3	Reference	1.352(1.100–1.662)	0.004	1.837(1.467–2.301)	<0.001

Notes: Model1 adjusted for age, sex. Model2 adjusted for age, sex, smoking, drinking, previous stroke, previous MI. Model3 adjusted for Age, Sex, Smoking, Drinking, Previous stroke, Previous MI, NYHA class, LDL-C, eGFR, LVEF, BNP. Nonmalnutrition (PNI≥45), mild malnutrition (40≤PNI<45), and malnutrition (PNI < 40).

Abbreviations: HR, hazard ratio; CI, confidential interval.

Figure 2 Kaplan‒Meier analyses of adverse outcomes categorized by PNI. (A) All-cause death. (B) Cardiovascular death.

Figure 3 Restricted cubic splines visualize the association between PNI and adverse outcomes in patients with metabolic syndrome and heart failure. (A) All-cause death. (B) Cardiovascular death.

Table 4 Prognostic Predictive Value of Different Indicators

	Sensitivity (%)	Specificity (%)	AUC (95% CI)	P
All-cause death
LYM	57.4	53.6	0.562(0.527–0.597)	0.001
ALB	69.0	54.1	0.610(0.576–0.644)	<0.001
PNI	70.7	56.3	0.610(0.575–0.644)	<0.001
Cardiovascular death
LYM	55.8	53.3	0.546(0.511–0.581)	0.010
ALB	59.7	57.2	0.598(0.564–0.632)	<0.001
PNI	70.2	57.2	0.605(0.571–0.639)	<0.001

Abbreviations: LYM, lymphocyte count; ALB, serum albumin; PNI, prognostic nutritional index. AUC, area under the curve; CI, confidential interval.

Table 5 Prognostic Predictive Value of Different Models

	AUC	P	NRI	P	IDI	P
All-cause death
Established risk factors	0.573(0.530–0.616)	0.001
+LYM	0.588(0.545–0.630)	<0.001	0.042	0.160	0.002	0.110
+ALB	0.619(0.577–0.661)	<0.001	0.139	<0.001	0.026	<0.001
+PNI	0.620(0.579–0.661)	<0.001	0.150	<0.001	0.029	<0.001
Cardiovascular death
Established risk factors	0.559(0.518–0.601)	0.005
+LYM	0.567(0.525–0.608)	0.002	0.037	0.184	0.002	0.112
+ALB	0.594(0.554–0.635)	<0.001	0.130	<0.001	0.025	<0.001
+PNI	0.596(0.555–0.636)	<0.001	0.130	<0.001	0.029	<0.001

Abbreviations: LYM, lymphocyte count; ALB, serum albumin; PNI, prognostic nutritional index. Established risk factors included age, sex, smoking, drinking, previous MI, previous Stroke, NYHA class, LDL-C, LVEF, BNP. AUC, area under the curve, NRI, net reclassification improvement, IDI, integrated discrimination improvement.

Table 6 Prognostic Value of PNI for All-Cause Death in Various Subgroups

	Unadjusted HR (95% CI)	P	Adjusted HR (95% CI)	P
Age
≥60 (n=755)	0.969(0.956–0.982)	<0.001	0.965(0.951–0.979)	<0.001
<60 (n=293)	0.967(0.948–0.987)	0.001	0.964(0.943–0.986)	0.002
Sex
Male (n=768)	0.967(0.955–0.979)	<0.001	0.966(0.952–0.979)	<0.001
Female (n=280)	0.976(0.954–0.999)	0.041	0.964(0.940–0.989)	0.005
LVEF
>40 (n=639)	0.969(0.955–0.982)	<0.001	0.967(0.952–0.982)	<0.001
≤40 (n=409)	0.969(0.952–0.986)	<0.001	0.968(0.950–0.988)	0.001

Notes: Adjusted for variables were age, sex, smoking, drinking, previous stroke, previous MI, NYHA class, LDL-C, eGFR, LVEF, BNP.

Abbreviations: HR, hazard ratio; CI, confidential interval.