Table 3.
Interaction analyses for the association of tIS (combination of protein-bound and free fraction) with all-cause mortality
| Unadjusted |
Model 1 |
Model 2 |
Model 3 |
||||||
|---|---|---|---|---|---|---|---|---|---|
| Parameter | tIS median | HR (95% CI) | P-value | HR (95% CI) | P-value | HR (95% CI) | P-value | HR (95% CI) | P-value |
| Vintage: <3.6 years | 27.1 | 0.99 (0.87–1.13) | 0.90 | 0.99 (0.87–1.12) | 0.83 | 1.21 (1.06–1.39 | 0.004 | 1.20 (1.05–1.37) | 0.01 |
| Vintage: 3.6–9.6 years | 33.0 | 1.02 (0.92–1.12) | 0.76 | 1.01 (0.90–1.12) | 0.90 | 1.16 (1.03–1.31 | 0.01 | 1.13 (1.00–1.28) | 0.05 |
| Vintage: 9.6+ years | 33.8 | 0.95 (0.84–1.07) | 0.39 | 0.99 (0.87–1.13) | 0.88 | 1.08 (0.94–1.25 | 0.28 | 1.07 (0.92–1.24) | 0.39 |
| Interaction P | 0.52 | 0.91 | 0.33 | 0.37 | |||||
| Age: <62.3 years | 31.9 | 1.09 (0.96–1.23) | 0.18 | 1.13 (1.00–1.27) | 0.05 | 1.26 (1.11–1.43 | 0.001 | 1.24 (1.09–1.41) | 0.001 |
| Age: 62.3–71.3 years | 32.2 | 0.99 (0.88–1.12) | 0.89 | 1.02 (0.90–1.15) | 0.77 | 1.16 (1.03–1.31 | 0.01 | 1.16 (1.03–1.30) | 0.01 |
| Age: 71.3+ years | 31.0 | 0.95 (0.84–1.07) | 0.41 | 0.95 (0.84–1.08) | 0.46 | 1.13 (0.98–1.30 | 0.10 | 1.10 (0.96–1.26) | 0.17 |
| Interaction P | 0.18 | 0.10 | 0.41 | 0.37 | |||||
| nPCR: <0.85 | 29.0 | 1.08 (0.95–1.23) | 0.25 | 1.09 (0.96–1.24) | 0.20 | 1.29 (1.15–1.44) | <.0001 | 1.29 (1.14–1.45) | <.0001 |
| nPCR: 0.85–1.01 | 32.1 | 0.91 (0.81–1.02) | 0.11 | 0.92 (0.83–1.03) | 0.15 | 1.08 (0.95–1.21) | 0.24 | 1.05 (0.94–1.18) | 0.39 |
| nPCR: 1.01+ | 33.7 | 0.93 (0.82–1.05) | 0.25 | 0.98 (0.87–1.10) | 0.71 | 1.12 (0.98–1.29) | 0.09 | 1.11 (0.97–1.26) | 0.13 |
| Interaction P | 0.07 | 0.03 | 0.01 | 0.004 | |||||
| Albumin: <3.6 g/dL | 33.7 | 1.05 (0.92–1.20) | 0.48 | 1.08 (0.94–1.23) | 0.28 | 1.17 (1.02–1.35) | 0.02 | 1.15 (1.00–1.33) | 0.05 |
| Albumin: 3.6+ g/dL | 28.5 | 1.05 (0.95–1.16 | 0.32 | 1.08 (0.97–1.20) | 0.17 | 1.14 (1.02–1.27) | 0.02 | 1.12 (1.01–1.25) | 0.04 |
| Interaction P | 0.97 | 0.96 | 0.66 | 0.68 | |||||
| spKt/V urea: <1.30 | 30.3 | 0.95 (0.85–1.07) | 0.39 | 0.97 (0.87–1.08) | 0.57 | 1.17 (1.04–1.31) | 0.01 | 1.15 (1.02–1.30) | 0.02 |
| spKt/Vurea: 1.30–1.54 | 32.6 | 0.96 (0.85–1.09 | 0.56 | 0.97 (0.86–1.10) | 0.66 | 1.13 (0.99–1.30) | 0.07 | 1.11 (0.97–1.27) | 0.13 |
| spKt/Vurea: 1.54+ | 32.6 | 1.03 (0.91–1.16) | 0.68 | 1.08 (0.93–1.25) | 0.31 | 1.17 (1.01–1.36) | 0.04 | 1.16 (1.01–1.34) | 0.04 |
| Interaction P | 0.46 | 0.19 | 0.83 | 0.67 | |||||
| RKF+ | 28.6 | 1.02 (0.83–1.24) | 0.85 | 1.12 (0.92–1.35) | 0.25 | 1.44 (1.20–1.73) | 0.0001 | 1.37 (1.13–1.68) | 0.002 |
| RKF− | 32.4 | 0.94 (0.84–1.05) | 0.30 | 0.98 (0.87–1.09) | 0.68 | 1.13 (1.01–1.26) | 0.04 | 1.11 (0.99–1.24) | 0.08 |
| Interaction P | 0.53 | 0.27 | 0.02 | 0.06 | |||||
| HDF+ | 32.5 | 0.78 (0.57–1.08) | 0.13 | 0.80 (0.56–1.16) | 0.25 | 0.94 (0.68–1.31) | 0.73 | 0.93 (0.64–1.36) | 0.73 |
| HDF− | 31.6 | 0.98 (0.88–1.08) | 0.67 | 1.01 (0.92–1.11) | 0.81 | 1.17 (1.06–1.30) | 0.001 | 1.15 (1.04–1.27) | 0.01 |
| Interaction P | 0.21 | 0.24 | 0.18 | 0.27 | |||||
Associations represented as HR for tIS, per 10 μg/mL higher. Model 1 adjusts for age, sex, vintage and history of diabetes, and prior CVD. Model 2 adjusts for Model 1 covariates, plus markers of nutritional status (albumin, nPCR, BMI and creatinine) and single-pool Kt/V urea. Model 3 adjusts for Model 2 covariates, plus other potential confounders (log C-reactive protein, total calcium, alkaline phosphatase, serum phosphorus and use of HDF).