Table 3. Multiple regression model for the scales of fatigue.
| Variable | Unadjusted | Adjusted | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Regression coefficient | 95%CI | t value | p value | Regression coefficient | 95%CI | t value | p value | ||
| POMS (log-transformed) | |||||||||
| Age | 0.0002 | -0.0043 to 0.0048 | 0.10 | 0.92 | -0.0015 | -0.0070 to 0.0039 | -0.56 | 0.57 | |
| Male gender | -0.0639 | -0.1723 to 0.0445 | -1.16 | 0.25 | -0.0088 | -0.1322 to 0.1147 | -0.14 | 0.89 | |
| Dialysis duration * | 0.0146 | -0.0264 to 0.0556 | 0.70 | 0.48 | -0.0111 | -0.0713 to 0.0491 | -0.36 | 0.72 | |
| Employed | -0.0824 | -0.1831 to 0.0183 | -1.61 | 0.11 | -0.1020 | -0.2230 to 0.0191 | -1.66 | 0.10 | |
| Smoker | -0.016 | -0.195 to 0.162 | -0.18 | 0.86 | |||||
| Dialysis modality | |||||||||
| HD | Ref. | Ref. | |||||||
| Online HDF | -0.0290 | -0.1884 to 0.1303 | -0.36 | 0.72 | -0.0493 | -0.2179 to 0.1192 | -0.58 | 0.56 | |
| PD | -0.0637 | -0.2249 to 0.0975 | -0.78 | 0.44 | -0.0517 | -0.2546 to 0.1512 | -0.5 | 0.62 | |
| Combined therapy | 0.0633 | -0.1306 to 0.2572 | 0.64 | 0.52 | 0.0757 | -0.1573 to 0.3086 | 0.64 | 0.52 | |
| CVD | -0.0583 | -0.1683 to 0.0518 | -1.04 | 0.30 | -0.0834 | -0.2014 to 0.0347 | -1.39 | 0.17 | |
| Diabetes | -0.0291 | -0.1418 to 0.0837 | -0.51 | 0.61 | 0.0186 | -0.1057 to 0.1429 | 0.29 | 0.77 | |
| BMI | -0.0115 | -0.0229 to -0.0002 | -2.01 | 0.046 | -0.0149 | -0.0279 to -0.0019 | -2.26 | 0.03 | |
| Hemoglobin | -0.0154 | -0.0578 to 0.0270 | -0.72 | 0.48 | -0.0240 | -0.0694 to 0.0213 | -1.05 | 0.30 | |
| Creatinine | 0.00889 | -0.00057 to 0.01834 | 1.85 | 0.07 | 0.01117 | 0.00088 to 0.02146 | 2.14 | 0.03 | |
| Urea nitrogen | -0.00022 | -0.00394 to 0.00351 | -0.12 | 0.91 | |||||
| Serum albumin | -0.0137 | -0.1274 to 0.1001 | -0.24 | 0.81 | 0.0135 | -0.1367 to 0.1637 | 0.18 | 0.86 | |
| CRP * | -0.0005 | -0.0469 to 0.0458 | -0.02 | 0.98 | |||||
| β2 microglobulin | 0.00515 | -0.00323 to 0.01353 | 1.22 | 0.23 | |||||
| Use of ESAs | 0.0724 | -0.0828 to 0.2275 | 0.92 | 0.36 | |||||
| VAS | |||||||||
| Age | -0.138 | -0.425 to 0.150 | -0.94 | 0.35 | -0.274 | -0.616 to 0.069 | -1.58 | 0.12 | |
| Male gender | 0.00 | -6.84 to 6.84 | 0.00 | 1.00 | 3.32 | -4.36 to 11.00 | 0.85 | 0.40 | |
| Dialysis duration * | 0.59 | -1.99 to 3.18 | 0.45 | 0.65 | 1.17 | -2.59 to 4.92 | 0.61 | 0.54 | |
| Employed | -6.63 | -12.92 to -0.34 | -2.08 | 0.04 | -9.73 | -17.34 to -2.13 | -2.53 | 0.01 | |
| Smoker | 3.63 | -7.74 to 15.00 | 0.63 | 0.53 | |||||
| Dialysis modality | |||||||||
| HD | Ref. | Ref. | |||||||
| Online HDF | -2.95 | -12.90 to 6.99 | -0.59 | 0.56 | -3.70 | -14.19 to 6.79 | -0.70 | 0.49 | |
| PD | 0.19 | -9.88 to 10.27 | 0.04 | 0.97 | 0.95 | -11.74 to 13.64 | 0.15 | 0.88 | |
| Combined therapy | 5.67 | -6.55 to 17.88 | 0.92 | 0.36 | 3.71 | -10.80 to 18.21 | 0.50 | 0.61 | |
| CVD | -0.08 | -6.99 to 6.82 | -0.02 | 0.98 | -1.21 | -8.60 to 6.18 | -0.32 | 0.75 | |
| Diabetes | 2.08 | -5.02 to 9.17 | 0.58 | 0.57 | 2.88 | -4.93 to 10.68 | 0.73 | 0.47 | |
| BMI | -0.122 | -0.838 to 0.593 | -0.34 | 0.74 | -0.439 | -1.251 to 0.373 | -1.07 | 0.29 | |
| Hemoglobin | 1.30 | -1.35 to 3.95 | 0.97 | 0.34 | 0.89 | -1.95 to 3.72 | 0.62 | 0.54 | |
| Creatinine | 0.698 | 0.110 to 1.287 | 2.34 | 0.02 | 0.804 | 0.163 to 1.444 | 2.47 | 0.01 | |
| Urea nitrogen | -0.188 | -0.423 to 0.047 | -1.58 | 0.12 | |||||
| Serum albumin | -4.38 | -11.45 to 2.69 | -1.22 | 0.22 | -2.29 | -11.64 to 7.05 | -0.48 | 0.63 | |
| CRP * | 1.99 | -0.81 to 4.80 | 1.40 | 0.16 | |||||
| β2 microglobulin | 0.325 | -0.190 to 0.840 | 1.25 | 0.21 | |||||
| Use of ESAs | -0.26 | -9.98 to 9.45 | -0.05 | 0.96 | |||||
| Our original scale of fatigue | |||||||||
| Age | 0.00995 | -0.00290 to 0.02281 | 1.53 | 0.13 | -0.00397 | -0.01915 to 0.01120 | -0.52 | 0.61 | |
| Male gender | -0.126 | -0.434 to 0.182 | -0.81 | 0.42 | 0.115 | -0.230 to 0.460 | 0.66 | 0.51 | |
| Dialysis duration * | 0.0775 | -0.0389 to 0.1938 | 1.31 | 0.19 | 0.1007 | -0.0664 to 0.2678 | 1.19 | 0.24 | |
| Employed | -0.465 | -0.744 to -0.186 | -3.29 | 0.00 | -0.339 | -0.679 to -0.0003 | -1.98 | 0.050 | |
| Smoker | -0.433 | -0.932 to 0.065 | -1.72 | 0.09 | -0.230 | -0.756 to 0.296 | -0.86 | 0.39 | |
| Dialysis modality | |||||||||
| HD | Ref. | Ref. | |||||||
| Online HDF | -0.323 | -0.766 to 0.120 | -1.44 | 0.15 | -0.234 | -0.707 to 0.239 | -0.98 | 0.33 | |
| PD | -0.387 | -0.835 to 0.061 | -1.70 | 0.09 | -0.142 | -0.708 to 0.424 | -0.50 | 0.62 | |
| Combined therapy | 0.269 | -0.270 to 0.808 | 0.99 | 0.33 | 0.243 | -0.408 to 0.893 | 0.74 | 0.46 | |
| CVD | -0.066 | -0.379 to 0.247 | -0.41 | 0.68 | -0.217 | -0.547 to 0.113 | -1.30 | 0.20 | |
| Diabetes | 0.274 | -0.044 to 0.591 | 1.70 | 0.09 | 0.257 | -0.091 to 0.605 | 1.46 | 0.15 | |
| BMI | -0.0126 | -0.0451 to 0.0198 | -0.77 | 0.44 | -0.0135 | -0.0496 to 0.0226 | -0.74 | 0.46 | |
| Hemoglobin | 0.0468 | -0.0733 to 0.1669 | 0.77 | 0.44 | -0.0017 | -0.1290 to 0.1255 | -0.03 | 0.98 | |
| Creatinine | -0.0254 | -0.0522 to 0.0014 | -1.87 | 0.06 | -0.0202 | -0.0488 to 0.0084 | -1.39 | 0.17 | |
| Urea nitrogen | -0.00297 | -0.01353 to 0.00758 | -0.56 | 0.58 | |||||
| Serum albumin | -0.140 | -0.459 to 0.179 | -0.87 | 0.39 | 0.005 | -0.414 to 0.425 | 0.03 | 0.98 | |
| CRP * | 0.0403 | -0.0843 to 0.1648 | 0.64 | 0.52 | |||||
| β2 microglobulin | 0.0103 | -0.0122 to 0.0329 | 0.91 | 0.37 | |||||
| Use of ESAs | -0.145 | -0.585 to 0.296 | -0.65 | 0.52 | |||||
Abbreviations: CI, confidence interval; POMS, Profile of Mood States; HD, hemodialysis; HDF, hemodiafiltration; PD, peritoneal dialysis; CVD, cardiovascular disease; BMI, body mass index; CRP, C-reactive protein; ESAs, erythropoiesis-stimulating agents; VAS, Visual Analogue Scale.
* Dialysis duration and CRP are log-transformed.