Association of short-term blood pressure variability with cardiovascular mortality among incident hemodialysis patients

Figures & data

Table 1. Baseline characteristics of participants.

Characteristics	All patients (n = 103)
Age (years)	57.49 ± 12.77
Sex (% men)	60 (58.25)
Body mass index (kg/m^2)	23.31 (20.22, 24.96)
Hemodialysis vintage (months)	68.39 ± 42.80
History of diabetes (%)	23 (22.33)
Laboratory values
Hemoglobin (g/L)	123.32 ± 11.78
Albumin (g/L)	37.46 ± 2.20
Prealbumin (g/L)	0.47 ± 0.09
Triglyceride (mmol/L)	1.93 ± 1.07
Total cholesterol (mmol/L)	4.44 ± 0.92
HDL-cholesterol (mmol/L)	0.93 ± 0.43
LDL-cholesterol (mmol/L)	2.31 ± 0.70
Calcium (mmol/L)	2.24 ± 0.18
Phosphorous (mmol/L)	1.82 ± 0.54
Hs-CRP (mg/L)	1.96 (1.11, 4.36)
Ferritin (ng/mL)	634.29 ± 367.95
iPTH (pg/ml)	250.28 (125.50, 445.70)
Ambulatory blood pressure monitoring
44-h SBP (mmHg)	157.09 ± 16.25
SD of 44-h SBP (mmHg)	20.06 ± 5.31
CV of 44-h SBP (%)	12.94 ± 3.76
ARV of 44-h SBP (mmHg)	18.26 ± 4.84

HDL: high-density lipoprotein; LDL: low-density lipoprotein; Hs-CRP: high-sensitivity C-reactive protein; iPTH: intact parathyroid hormone; SBP: systolic blood pressure; CV: coefficient of variation; ARV: average real variability.

Figure 1. Kaplan–Meier survival curves for cardiovascular mortality according to median of 44-h SBPSD.

Figure 2. Kaplan–Meier survival curves for cardiovascular mortality according to median of 44-h SBPCV.

Figure 3. Kaplan–Meier survival curves for cardiovascular mortality according to median of ARV.

Table 2. Risk factors for cardiovascular mortality in hemodialysis patients using cox regression analysis.

	Unadjusted		Minimally adjusted^a		Fully adjusted^b
Parameters	HR (95%CI)	p	HR (95%CI)	p	HR (95%CI)	p
ARV	1.157 (1.057–1.266)	.002	1.130 (1.020–1.252)	.019	1.143 (1.022–1.279)	.019
Hs-CRP	1.230 (1.092–1.386)	.001	1.178 (1.042–1.332)	.009	1.394 (1.025–1.363)	.021

Values expressed as hazard ratios (HR) and 95% confidence interval (CI).

Hs-CRP: high-sensitivity C-reactive protein; SBP: systolic blood pressure; ARV: average real variability.

^aAdjusted for ARV, hs-CRP, 44-h systolic blood pressure (44-h SBP) and phosphate level.

^bAdjusted for sex, dialysis vintage, BMI, IDWT, albumin level, ARV, hs-CRP, 44-h systolic blood pressure (44-h SBP) and phosphate level.

Figure 4. ROC curves for cardiovascular mortality with different blood pressure variability. BPV: blood pressure variability; CV: coefficient of variation; ARV: average real variability.

Table 3. Characteristics of study cohort by median of ARV.

Parameters	Low ARV (n = 57)	High ARV (n = 46)	p
Age (years)	53.89 ± 10.01	61.93 ± 14.44	.002
Sex (% men)	32 (56.14)	28 (60.87)	.628*
Body mass index (kg/m^2)	21.28 (19.05, 24.02)	24.32 (22.35, 25.95)	<.01^+
Hemodialysis vintage (months)	64.32 ± 47.73	73.43 ± 35.63	.285
History of diabetes (%)	7 (12.28)	16 (34.78)	.006*
Heart rates (bpm)	72.03 ± 7.20	75.35 ± 8.39	.033
IDWG (kg)	2.28 ± 0.92	2.83 ± 0.95	.004
Hemoglobin (g/L)	121.98 ± 10.58	124.98 ± 13.04	.201
Albumin (g/L)	36.54 ± 2.73	36.18 ± 3.02	.527
Calcium (mmol/L)	2.27 ± 0.18	2.22 ± 0.17	.139
Phosphorous (mmol/L)	1.84 ± 0.56	1.79 ± 0.51	.677
Triglyceride (mmol/L)	1.79 ± 1.10	2.11 ± 1.02	.134
Total cholesterol (mmol/L)	4.43 ± 0.93	4.44 ± 0.92	.906
Ferritin (ng/mL)	614.38 ± 338.49	658.96 ± 403.95	.544
hs-CRP (mg/L)	1.82 (0.89, 2.55)	2.20 (1.61, 6.92)	.057^+

*p with χ² test and ⁺p with rank-sum test.

Hs-CRP: high-sensitivity C-reactive protein; IDWG: interdialytic weight gain; ARV: average real variability.

Table 4. Related factors for ARV using logistic regression analysis.

	Multivariate adjusted^a
Parameters	B	OR (95%CI)	p
Age	0.065	1.067 (1.018–1.117)	.005
IDWG	0.825	2.281 (1.416–4.321)	.003

Values expressed as odds ratio and 95%confidence interval (CI).

IDWG: interdialytic weight gain.

^aMultivariate model: adjusted for age, sex, diabetes mellitus, serum calcium, serum phosphate, hs-CRP, parathyroid hormone and interdialytic weight gain.