Table 1.

Selected studies supporting the use of higher dialysate sodium.

Author (Year) DNa Comparison	Patient and HD treatment characteristics	Study design	Outcomes			Comments
			Pre-HD BP	IDWG	IDH and symptoms
Early Studies, All Patients (No Mortality Data)
Stewart (1972)35 145 vs. 132 mEq/L	N=9 (960 tmts) -Twice weekly HD -Session length 16–22 h -Mean age NR	Cross-over (2 arms)	NR	NR	↓ cramping with higher DNa	-Small N -Twice weekly HD -Comorbidities unknown -BP and IDWG changes NR -Low sodium diet recommended but not evaluated -Acetate dialysate
Port (1973)37 133 + hypertonic saline infusion vs. 133 mEq/L	N=17 (22 tmts) -Incident and prevalent -Mean age 37y -Session length 4 h -Qb 250 mL/min -Qd 1000 mL/min	Quasi-randomized (Attempte d to have similar pre-HD BUN in each group)	↑ reduction in pre-HD SBP with lower DNa	↓ IDWG with lower DNa	↑ intradialytic BP with higher DNa ↑ disequilibrium symptoms with lower DNa ↑ frequency of EEG abnormalities with lower DNa	-Small N -Comorbidities unknown -Acetate dialysate
Dumler (1979)39 150 x 3h, then 130 x 1h vs. 140 mEq/L x 4h	N=10 (2 wks/ arm) -Prevalent -Mean age 56y	Double-blind cross-over (2 arms)	NS	NS	↓ BP decline with higher DNa ↓ cramping with higher DNa	-Small N -Comorbidities unknown -Acetate dialysate
Raja (1983)40 135 vs. 140 vs. 145→135 vs. 135→145 mEq/L	N=10 (2 wks/ arm) -Prevalent -Mean age 61y	Cross-over (4 arms); one week washout between each arm	NS	NS	↑ IDH with DNa of 135 (A) and with DNa modeled 135→145 (D)	-Small N -Comorbidities unknown -Acetate dialysate
Cybulsky (1985)38 144 vs. 133 mEq/L	N=16 (24 wks/arm) -Prevalent -Mean age 46y -Non-diabetic	Cross-over (2 arms)	NS	NS	↓ IDH events in normotensive and anephric patients	-Small N -Heterogeneous sample with normotensive, hypertensive and anephric patients -Acetate dialysate
Acchiardo (1991)41 149 →140 (linear) vs. 149 →140 (stepped) vs. 149 →140 (exponential) vs. 140 mEq/L (baseline)	N=39 (9 weeks; arm chosen randomly each week and compared with baseline) -Prevalent -Mean age 49y	Cross-over (3 arms)	NS	NS	↓ IDH and cramping with modeled DNa	-Small N -TT 2 h -Bicarbonate dialysate -Comorbidities unknown
Hypotension Prone Patients (No Mortality Data)
Levin (1996)44 Modeled 155–160→140 vs. fixed 140 mEq/L	N=16 (3 wks/arm) -Prevalent -Mean age NR	Double-blind cross-over (2 arms)	NS	NS	↑ patient-reported preference for higher DNa	-Small N -Multiple comparisons -Intra-dialytic BP changes NR -Comorbidities unknown -Different starting DNa and UF protocols
Sang (1997)42 140 vs. linear 155→140 vs. stepped 155→140 mEq/L	N=23 (414 tmts; 2 wks/arm) -Prevalent -Mean age 59y	Randomized, blinded cross-over (3 arms)	↑ pre-HD BP with stepped modeling	↑ IDWG with linear and stepped modeling	↓ IDH with stepwise ↓ cramping with linear modeling ↑ thirst and fatigue with both stepped and linear	-Small N -6 patients did not complete protocol and were excluded -Bicarbonate dialysate
Oliver (2001)48 Modeled 152→142 +UF profiling versus 142 mEq/L + fixed UF rate	N=33 (2 wks/arm) -Prevalent -Mean age~69y	Randomized cross-over (2 arms)	NS	↑ IDWG with higher DNa	↓ symptoms with modeled DNa ↓ IDH with modeled DNa	-Small N -Non-blinded -Protocol compared UF profiling versus fixed UF rates as well
Song (2002)43 Combinations of fixed and modeled DNa with UF profiles vs. constant DNa 138 mEq/L	N=11 (264 tmts; 33 sessions per arm) -Prevalent -Mean age 54y	Randomized cross-over (8 arms)	NS	↑ IDWG with sodium modeling	↓ treatment failuresa with sodium modeling	-Small N -Complex protocol -Multiple comparisons
All patients (Mortality Data)
Mc Causland (2012)14 >140 or modeled vs. ≤140 mEq/L	N=2,272 -Thrice weekly HD -Prevalent -Mean age 62y	Observational cohort	NS	↑ IDWG with higher DNa	NR	-Higher Dialysate sodium associated with greater mortality in those with higher SNa
Hecking (2012)13 >140 vs. 140 vs. <140 mEq/L	N=11,555 -Thrice weekly HD -Prevalent -Mean age 62y	Observati onal cohort	NR	NR	NR	-Excluded sodium modeling -Dialysate sodium >140 (vs. 140) associated with ↓ mortality among patients with pre-HD SNa <137 mmol/L
Hecking (2012)46 >140 vs. 140 vs. <140 mEq/L	N=23,593 -Thrice weekly HD -Prevalent -Mean age 63y	Observational cohort	↓ pre-HD BP with higher DNa	↑ IDWG with higher DNa	NR	-DNa >140 associated with ↓ risk of hospitalization in full cohort -When restricted to facilities with standard (non-individualized) DNa, DNa >140 was associated with ↓ all-cause and CV-mortality

^aTreatment failure defined as at least 1 of the following: HD treatment stopped before 75% of prescribed time completed; % UF achieved <70%; Kt/V <1.1.

Abbreviations: DNa, dialysate sodium; wks, weeks; tmt, treatment; HD, hemodialysis; BP, blood pressure; IDWG, interdialytic weight gain; NS, non-significant (p>0.05) difference; NR, not reported; CV, cardiovascular; BUN, blood urea nitrogen.