Association of brachial-ankle pulse wave velocity with cognitive impairment in peritoneal dialysis patients

Figures & data

Figure 1. Flow chart.

Table 1. Comparison of demographic and clinical data.

Variables	Total (n = 643)	Cognitive impairment (n = 321)	Normal cognitive function (n = 322)	p Values
Age (years)	45 (37–57.4)	52.5 (43.2–62.7)	39.5 (33.6–47.4)	<.001
Female (n, %)	271 (42.1%)	158 (49.2%)	113 (35.1%)	<.001
Accepted below 12 years education (n, %)	289 (44.9%)	192 (59.8%)	97 (30.1%)	<.001
Primary renal disease (n, %)				<.001
Glomerulonephritis	445 (69.2%)	200 (62.3%)	245 (76.1%)
Diabetic nephropathy	84 (13.1%)	67 (20.9%)	17 (5.3%)
Renal vascular diseases	51 (7.9%)	29 (9.0%)	22 (6.8%)
Other	63 (9.8%)	25 (7.8%)	38 (11.8%)
Diabetes mellitus (n, %)	105 (16.3%)	84 (26.2%)	21 (6.5%)	<.001
Cardiovascular disease (n, %)	94 (14.6%)	66 (20.6%)	28 (8.7%)	<.001
Charlson comorbidity index (points)	3 (2–4)	3 (2–5)	2 (2–3)	<.001
Duration of peritoneal dialysis (months)	27.8 (8.7–56.4)	34.2 (9.7–59.6)	23 (7.5–50.8)	.009
Smoking (n, %)				.39
Never	492 (76.5%)	240 (76.9%)	252 (80.0%)
Ever	66 (10.3%)	37 (11.9%)	29 (9.2%)
Smoking	69 (10.7%)	35 (11.2%)	34 (10.8%)
Body mass index (kg/m^2)	22.4 ± 3.3	22.7 ± 3.4	22.1 ± 3.2	.03
Hemoglobin (g/L)	113.6 ± 18.9	112.9 ± 18.8	114.3 ± 19.0	.35
Blood platelet count (×10^9/L)	238.0 ± 69.7	245.2 ± 72.2	230.8 ± 66.4	.009
High-sensitivity C-reactive protein (mg/L)	1.5 (0.6–4.0)	2.0 (0.8–5.3)	1.1 (0.5–3.2)	<.001
Serum albumin (g/L)	36.6 ± 4.4	35.7 ± 4.2	37.5 ± 4.4	<.001
Serum calcium (mmol/L)	2.3 ± 0.2	2.3 ± 0.2	2.3 ± 0.2	.01
Serum phosphorus (mmol/L)	1.6 (1.3–1.9)	1.5 (1.3–2.0)	1.6 (1.3–1.9)	.93
Intact parathyroid hormone (pg/mL)	290.7 (149.9–580.3)	279.7 (133.1–640.1)	293.6 (173.5–571.8)	.45
Total cholesterol (mmol/L)	5 (4.3–5.9)	5.2 (4.3–6.0)	4.9 (4.2–5.6)	.006
Triglycerides (mmol/L)	1.5 (1.1–2.1)	1.6 (1.1–2.2)	1.4 (1.1–2.1)	.04
Blood urea nitrogen (mmol/L)	17.5 (14.1–21.5)	17.7 (14.1–22.4)	17.3 (14.2–20.5)	.37
Serum creatinine (umol/L)	972 (751–1215)	901(704–1152.5)	1027.5 (795–1262.5)	<.001
Residual renal function (mL/min/1.73 m^2)	1.3 (0.04–3.3)	1.2 (0.02–3.4)	1.5 (0.07–3.1)	.77
Clearance index of urea	2.2 (1.9–2.6)	2.3 (1.9–2.7)	2.2 (1.9–2.6)	.09
Brachial pulse wave velocity (m/s)	17.2 ± 5.6	18.6 ± 7.0	15.8 ± 3.2	<.001
Heart rate (bpm)	78.2 ± 19.1	79 ± 19.2	77.2 ± 19	.22
Systolic blood pressure (mmHg)	147.2 ± 21	150.3 ± 21.5	144.2 ± 20.2	<.001
Diastolic blood pressure (mmHg)	91.2 ± 13.0	90.6 ± 12.8	91.7 ± 13.1	.29
Pulse pressure (mmHg)	56.1 ± 13.7	59.7 ± 14.7	52.5 ± 11.6	<.001
Ankle-brachial index	1.14 ± 0.11	1.12 ± 0.12	1.15 ± 0.09	<.001
Augmentation index	11.7 (−0.5–24.9)	11.9 (1.2–24.6)	11.4 (−2.0–24.9)	.22
Score of Montreal cognitive assessment (points)	24.1 ± 4.3	20.8 ± 3.8	27.5 ± 1.2	<.001

Figure 2. Performance of different measurement of arterial stiffness in predicting cognitive impairment in the receiver operating characteristic analysis.

Table 2. Correlation between Arterial stiffness relevant indicators and cognitive function.

Variables	Total Score of MoCA		Cognitive impairment
	r	p Values	r'	p Values
Brachial pulse wave velocity (m/s)	−0.35	<.001	0.32	<.001
Heart rate (bpm)	−0.08	.03	0.08	.05
Systolic blood pressure (mmHg)	−0.14	<.001	0.14	<.001
Diastolic blood pressure (mmHg)	0.07	.09	−0.05	.19
Pulse pressure (mmHg)	−0.26	<.001	0.25	<.001
Ankle-brachial index	0.16	<.001	−0.12	.002
Augmentation index	−0.07	.09	0.05	.23

MoCA: Montreal Cognitive Assessment; r: Pearson correlation coefficient; r': Spearman’s correlation coefficient.

Table 3. Associations between brachial pulse wave velocity and score of Montreal cognitive assessment by linear regression analysis.

Variables	Univariate linear regression			Multivariate linear regression
	B	95%CI for B	p Values	B	95%CI for B	p Values
Age (per 1 year)	−0.17	−0.19 to −0.15	<.001	−0.12	−0.14 to −0.09	<.001
Female (yes)	−1.59	−2.26 to −0.91	<.001	−0.94	−1.59 to −0.28	.005
Accepted below 12 years education (yes)	−3.16	−3.79 to −2.53	<.001	−2.07	−2.63 to −1.51	<.001
Diabetes mellitus (yes)	−3.49	−4.36 to −2.62	<.001	−1.47	−2.27 to −0.67	<.001
Duration of peritoneal dialysis (per 1 month)	−0.01	−0.02 to −0.001	.035	−0.001	−0.01 to −0.01	.778
Smoking (yes)	−0.09	−0.61–0.43	.731	−0.01	−0.47–0.44	.955
Blood platelet count (per 1 × 10^9/L)	−0.01	−0.01 to −0.002	.006	−0.002	−0.01–0.002	.367
High-sensitivity C-reactive protein (per 1 mg/L)	−0.06	−0.10 to −0.03	.001	−0.01	−0.05–0.02	.457
Serum albumin (per 1 g/L)	0.21	0.13–0.28	<.001	0.05	−0.02–0.11	.166
Total cholesterol (per 1 mmol/L)	−0.62	−0.90 to −0.34	<.001	−0.24	−0.48–0.01	.062
Serum creatinine (per 1 umol/L)	0.003	0.002–0.004	<.001	0	−0.001–0.001	.372
Brachial pulse wave velocity (per 5.6 m/s)	−1.30	−1.62 to −0.98	<.001	−0.42	−0.71–−0.12	.006

B, unstandardized coefficients; 95% CI；95% confidence interval.

Note: Odds ratio and 95% confidence interval of brachial pulse wave velocity were calculated for a 1 standard deviation increase in linear regression analysis.

Table 4. Univariate binary logistic regression analysis for the influence factors of cognitive impairment in peritoneal dialysis patients.

Variables	OR	95% CI	p Values
Age (per 1 year)	1.08	1.06–1.09	<.001
Female (yes)	1.79	1.31–2.46	<.001
Accepted below 12 years education (yes)	3.45	2.49–4.78	<.001
Diabetes mellitus (yes)	5.08	3.06–8.44	<.001
Duration of peritoneal dialysis (per 1 month)	1.01	1.001–1.01	.014
Smoking (yes)	1.08	0.86–1.37	.509
Body mass index (per 1 kg/m^2)	1.05	1.01–1.11	.032
Blood platelet count (per 1× 10^9/L)	1.00	1.00–1.01	.010
High-sensitivity C-reactive protein (per 1 mg/L)	1.03	1.01–1.05	.014
Serum albumin (per 1 g/L)	0.91	0.88–0.95	<.001
Serum calcium (per 1 mmol/L)	0.37	0.17–0.81	.013
Total cholesterol (per 1 mmol/L)	1.22	1.07–1.40	.003
Serum creatinine (per 1 umol/L)	0.99	0.99–1.00	<.001
Brachial pulse wave velocity (per 5.6 m/s)	2.84	2.12–3.80	<.001
Systolic blood pressure (per 21 mmHg)	1.35	1.15–1.58	<.001
Pulse pressure (per 13.7 mmHg)	1.76	1.49–2.09	<.001
Ankle-brachial index (per 0.11)	0.76	0.64–0.90	.002

OR: odds ratio; 95% CI: 95% confidence interval

Note: For arterial stiffness relevant indicators, odds ratios and 95% confidence intervals were calculated for a 1 standard deviation increase in univariate binary logistic regression analysis.

Table 5. Associations between arterial stiffness relevant indicators and cognitive impairment by binary logistic regression analysis.

Model	Model 1		Model 2		Model 3
	OR (95% CI)	p Values	OR (95% CI)	p Values	OR (95% CI)	p Values
Brachial pulse wave velocity (per 5.6 m/s)	2.84 (2.12–3.80)	<.001	1.65 (1.18–2.32)	.004	1.55 (1.11–2.17)	.011
Systolic blood pressure (per 21 mmHg)	1.35 (1.15–1.58)	<.001	1.32 (1.10–1.59)	.003	1.33 (1.09–1.62)	.006
Pulse pressure (per 13.7 mmHg)	1.76 (1.49–2.09)	<.001	1.33 (1.08–1.63)	.006	1.34 (1.08–1.67)	.009
Ankle-brachial index (per 0.11)	0.76 (0.64–0.90)	.002	1.03 (0.84–1.27)	.771	1.03 (0.83–1.28)	.788

OR: odds ratio; 95% CI: 95% confidence interval

Note: For arterial stiffness relevant indicators, odds ratios and 95% confidence intervals were calculated for a 1 standard deviation increase in binary logistic regression analysis.