The relationship of platelet distribution width with all-cause and cardiovascular mortality in peritoneal dialysis patients

Figures & data

Figure 1. Study flow chart. PDW: platelet distribution width; ROC: receiver-operating characteristic curves.

Figure 2. Receiver operating characteristic curve of PDW that predicted all-cause mortality. AUC: Area under the curve.

Table 1. Comparisons of baseline data between the two groups before PSM.

	PDW < 11.95%	PDW ≥ 11.95%
Variables	n = 307	n = 413	p Value
Male, n (%)	168(54.7)	250(57.9)	0.118
Age (years)	44(33,54)	43(34,55)	0.586
Causes of ESRD, n (%)
Chronic glomerulonephritis	231(75.3)	324(78.4)	0.778
Diabetic nephropathy	31(10.1)	35(8.5)	0.430
Hypertensive nephropathy	9(2.9)	10(2.4)	0.333
Others	36(11.7)	44(10.7)	0.324
Albumin (g/L)	37.70(33.60,41.60)	38.80(35.10,42.10)	<0.05
Total cholesterol (mmol/L)	4.50(3.75,5.47)	4.32(3.57,5.35)	0.085
Triglycerides (mmol/L)	1.67(1.22,2.50)	1.54(1.09,2.20)	<0.05
Serum urea nitrogen (mg/dL)	73.70(57.10,93.10)	71.50(56.55,91.40)	0.508
Creatinine (mg/dL)	7.82(6.09,9.86)	7.45(5.79,9.31)	0.067
Cystatin C (mg/L)	4.79(4.05,5.52)	4.66(3.92,5.27)	<0.05
Uric acid (umol/L)	520 ± 141	544(461,629)	<0.05
Alanine transaminase (U/L)	15(10,23)	16(11,25)	0.055
Glutamate transaminase (U/L)	16(12,22)	18(14,23)	<0.05
Serum calcium (mmol/L)	2.10(1.97,2.26)	2.12(1.99,2.24)	0.779
Serum phosphorus (mmol/L)	1.75(1.53,2.11)	1.77(1.48,2.11)	0.694
Body mass index (kg/m^2)	22.00(19.62,24.20)	21.70(19.70,24.00)	0.530
eGFR (mL/[min·1.73m^2)	7(5,9)	7(6,10)	0.082
Hemoglobin (g/L)	85(75,100)	90(77,103)	0.118
Platelet counts (×10^9/L)	178(129,227)	155(117,196)	<0.05
History of hypertension, n (%)	279(90.9)	382(91.5)	0.435
History of diabetes, n (%)	49(16.0)	50(12.1)	0.088
CCI	2.36 ± 0.71	2.30 ± 0.67	0.443
C-reactive protein	4.35 ± 13.59	4.90 ± 16.49	0.731

PSM: propensity score matching; PDW: platelet distribution width; ESRD: end-stage renal disease; eGFR: estimated glomerular filtration rate; CCI: Charlson comorbidity index.

Table 2. Comparisons of baseline data between the two groups after PSM.

	PDW < 11.95%	PDW ≥ 11.95%
Variables	n = 213	n = 213	p Value
Male, n (%)	118(55.4)	122(57.3)	0.696
Age (years)	44(35,55)	43(33,55)	0.364
Causes of ESRD, n (%)
Chronic glomerulonephritis	162(76.1)	164(77.0)	0.538
Diabetic nephropathy	17(8.0)	16(7.5)	0.145
Hypertensive nephropathy	12(5.6)	10(4.7)	0.347
Others	22(10.3)	23(10.8)	0.742
Creatinine (mg/dL)	7.84(6.27,9.90)	7.61(6.20,9.74)	0.706
Cystatin C (mg/L)	4.79(4.14,5.35)	4.87(4.15,5.44)	0.635
Uric acid (umol/L)	531 ± 136	536(461,615)	0.738
Alanine transaminase (U/L)	15(10,23)	14(10,21)	0.444
Glutamate Transaminase (U/L)	197(12,22)	17(13,21)	0.656
Serum calcium (mmol/L)	2.10(1.98,2.26)	2.11(1.94,2.23)	0.631
Serum phosphorus (mmol/L)	1.76(1.54,2.16)	1.82(1.49,2.16)	0.857
Body mass index (kg/m^2)	22.30(19.97,24.31)	21.70(19.66,24.00)	0.438
eGFR (mL/[min·1.73m^2)	7(5,9)	7(5,9)	0.996
Hemoglobin (g/L)	84(74,99)	89 ± 20	0.135
Platelet counts (×10^9/L)	164(123,213)	166(135,204)	0.949
History of hypertension, n (%)	197(92.5)	193(90.6)	0.486
History of diabetes, n (%)	29(13.6)	28(13.1)	0.887
CCI	2.27 ± 0.65	2.30 ± 0.65	0.709
C-reactive protein	4.35 ± 14.49	4.22 ± 15.50	0.947

PSM: propensity score matching; PDW: platelet distribution width; ESRD: end-stage renal disease; eGFR: estimated glomerular filtration rate; CCI: Charlson comorbidity index.

Figure 3. The Kaplan–Meier survival analysis for all-cause mortality after propensity score matching. PDW: platelet distribution width.

Figure 4. The Kaplan–Meier survival analysis for cardiovascular mortality after propensity score matching. PDW: platelet distribution width.

Table 3. Cox regression analysis of PDW in association with all-cause and cardiovascular mortality after propensity score matching.

	Model 1		Model 2		Model 3
	HR (95% CI)	p Value	HR (95% CI)	p Value	HR (95% CI)	p Value
All-cause mortality
Continuous variable
PDW (%)	1.153(1.061,1.252)	0.001	1.189(1.085,1.303)	<0.001	1.162(1.057,1.278)	0.002
Dichotomous variable
PDW < 11.95%	Reference		Reference		Reference
PDW ≥ 11.95%	2.556(1.304,5.010)	0.006	2.179(1.094,4.340)	0.027	2.138(1.071,4.267)	0.031
Cardiovascular mortality
Continuous variable
PDW (%)	1.177(1.040,1.331)	0.010	1.210(1.049,1.395)	0.009	1.200(1.041,1.382)	0.012
Dichotomous variable
PDW < 11.95%	Reference		Reference		Reference
PDW ≥ 11.95%	13.667(1.826,102.298)	0.011	11.333(1.498,85.730)	0.019	11.703(1.536,89.172)	0.018

Model 1: crude analysis. Model 2: adjustment for sex, age, CCI, BMI. Model 3 of all-cause mortality: adjustment for Model 2 and albumin, total cholesterol, hemoglobin, and the history of diabetes. Model 3 of cardiovascular mortality: adjustment for Model 2 and cystatin C. PDW: platelet distribution width; CCI: Charlson comorbidity index.

Figure 5. Restricted cubic spline analyses of the relationship between PDW and all-cause mortality after propensity score matching. PDW: platelet distribution width.

Figure 6. Restricted cubic spline analyses of the relationship between PDW and cardiovascular mortality after propensity score matching. PDW: platelet distribution width.

Figure 7. Correlation analysis of platelet counts and PDW after propensity score matching. PDW: platelet distribution width.

Table 4. Pearson correlation analysis of factors associated with PDW after propensity score matching.

Variables	r	p Value
Age (years)	−0.020	0.686
Albumin (g/L)	0.008	0.874
Serum urea nitrogen (mg/dL)	−0.009	0.847
Creatinine (mg/dL)	−0.009	0.861
Uric acid (umol/L)	−0.029	0.556
Serum calcium (mmol/L)	−0.079	0.105
Serum phosphorus (mmol/L)	−0.081	0.094
Body mass index (kg/m^2)	−0.014	0.773
eGFR (mL/[min·1.73 m^2)	−0.011	0.821
Hemoglobin (g/L)	0.022	0.654
Platelet counts (×10^9/L)	−0.108	0.025
CRP	0.025	0.704
CCI	−0.014	0.775

PDW: platelet distribution width; eGFR: estimated glomerular filtration rate; CRP: C-reactive protein; CCI: Charlson comorbidity index.

Data availability statement

The datasets in this study are available from the corresponding author on reasonable request.