Table 3.

Association between systolic blood pressure (SBP) and risk of cardiovascular (CVD) events (N=377)

Blood pressure measure	CVD Events		Unadjusted		Model 1: Adjusted for age, sex and race/ethnicity		Model 2: Adjusted for patient characteristics*		Model 3: Adjusted for patient characteristics + dialysis variables†
Dialysis-unit-SBP (mmHg)	Number of events	Rate (per 100py)	HR (95% CI)	p value	HR (95%CI)	p value	HR (95%CI)	p value	HR (95%CI)	p value
Q1 (94–137)	26	11.98	1.00 (0.59, 1.72)	1.0	0.93 (0.54, 1.60)	0.8	0.86 (0.49, 1.51)	0.6	0.75 (0.44, 1.39)	0.4
Q2 (138–152)	27	11.85	Ref		Ref		Ref		Ref
Q3 (153 -165)	26	10.53	0.89 (0.52, 1.53)	0.7	0.93 (0.54, 1.59)	0.8	0.81 (0.47, 1.41)	0.5	0.65 (0.36, 1.18)	0.2
Q4 (166–211)	34	16.24	1.37 (0.82, 2.27)	0.2	1.45 (0.87, 2.41)	0.2	1.40 (0.83, 2.35)	0.2	1.06 (0.60, 1.85)	0.9
Out-of-dialysis-unit-SBP (mmHg)	Number of events	Rate (per 100py)	HR (95% CI)	p value	HR (95%CI)	p value	HR (95%CI)	p value	HR (95%CI)	p value
Q1 (70–112)	21	8.11	Ref		Ref		Ref		Ref
Q2 (113–127)	25	10.79	1.32 (0.74, 2.35)	0.4	1.27 (0.71, 2.28)	0.4	1.20 (0.66, 2.17)	0.6	1.33 (0.71, 2.50)	0.4
Q3 (128–145)	33	15.13	1.84 (1.07, 3.19)	0.03	1.69 (0.98, 2.93)	0.06	1.77 (1.01, 3.11)	0.047	2.14 (1.17, 3.90)	0.01
Q4 (146–238)	34	17.68	2.14 (1.24, 3.69)	0.006	2.24 (1.29, 3.89)	0.004	2.44 (1.38, 4.29)	0.002	2.90 (1.55, 5.42)	<0.001

^*patient characteristics include: age, gender, race/ethnicity, tobacco use, BMI, diabetes, history of cardiovascular disease (covariates taken from same visit/closest prior visit of SBP reading)

^†dialysis variables: Kt/V, serum albumin and hemoglobin level