Table 3.

Association of KDa with mortality

Patient LevelInstrumental Variable Approach
KD ≤1.5 (versus ≥3)KD=2–2.5 (versus ≥3)KD ≤1.5 (versus ≥3)KD=2–2.5 (versus ≥3)
HR95% CIPHR95% CIPHR95% CIPHR95% CIP
All patients (N=37,741)
 all-cause mortality1.13(1.03–1.25)0.011.08(1.01–1.16)0.031.09(0.88–1.35)0.431.23(1.04–1.45)0.01
 sudden death1.39(1.12–1.74)0.0041.17(1.01–1.37)0.041.67(0.99–2.81)0.051.61(1.12–2.30)0.01
 other cardiovascular death1.14(0.95–1.36)0.161.04(0.91–1.19)0.541.11(0.75–1.64)0.621.23(0.90–1.68)0.19
 noncardiovascular death0.99(0.84–1.17)0.931.05(0.94–1.16)0.380.84(0.61–1.16)0.291.03(0.83–1.29)0.76
Among patients with serum K ≥5 (n=17,327)
 all-cause mortality1.09(0.95–1.26)0.231.08(0.97–1.20)0.171.13(0.87–1.47)0.371.23(0.99–1.52)0.06
 sudden death1.21(0.91–1.61)0.181.11(0.90–1.38)0.331.27(0.73–2.22)0.401.30(0.81–2.08)0.28
 other cardiovascular death1.16(0.88–1.52)0.291.00(0.82–1.21)0.971.18(0.74–1.88)0.491.17(0.79–1.72)0.44
 noncardiovascular death0.97(0.77–1.22)0.811.10(0.93–1.31)0.271.02(0.70–1.47)0.931.21(0.87–1.69)0.25
Among patients with serum K <5 (n=20,414)
 all-cause mortality1.15(1.00–1.33)0.041.06(0.98–1.15)0.151.04(0.80–1.36)0.761.23(1.03–1.46)0.02
 sudden death1.53(1.10–2.13)0.011.18(0.98–1.42)0.082.01(0.96–4.24)0.061.86(1.31–2.63)<0.001
 other cardiovascular death1.05(0.85–1.31)0.641.05(0.88–1.24)0.580.94(0.56–1.56)0.801.23(0.86–1.76)0.26
 noncardiovascular death1.03(0.77–1.38)0.831.00(0.88–1.15)0.950.77(0.51–1.15)0.200.95(0.75–1.22)0.71
  • HRs and confidence intervals CIs adjusted for variables listed in Table 1 and in the Materials and Methods, stratified by phase and country and accounted for facility clustering. IV, instrumental variable; HR, hazard ratio; 95% CI, 95% confidence interval. KD, dialysate potassium.

  • a KD ≤1.5, n=5493; KD=2–2.5, n=25,552; KD≥3, n=6696.