Table 1. Baseline characteristics of the study population by the RDW groups.
| RDW ≤ 15.3% | RDW > 15.3% | p-value | |
|---|---|---|---|
| Number of patient | 155 | 158 | |
| Sex, men | 86 (55.48%) | 78 (49.37%) | 0.332 |
| Age (years) | 51.21 ± 14.83 | 57.89 ± 16.45 | <0.001* |
| Body mass index (kg/m2) | 23.91 ± 3.77 | 23.55 ± 4.08 | 0.418 |
| Smoker | 0.763 | ||
| never | 125 (80.65%) | 124 (78.48%) | |
| current | 5 (3.23%) | 4 (2.53%) | |
| ever | 25 (16.13%) | 30 (18.99%) | |
| Medication prescription | |||
| ACE inhibitor/ARB | 105 (67.74%) | 106 (67.09%) | 0.998 |
| Erythropoiesis stimulating agents | 146 (94.19%) | 153 (96.84%) | 0.287 |
| Calcium supplement | 141 (90.97%) | 140 (88.61%) | 0.577 |
| Iron preparation | 135 (87.1%) | 123 (77.85%) | 0.038* |
| Folic acid | 149 (96.13%) | 150 (94.94%) | 0.786 |
| Vitamin B12 | 5 (3.23%) | 8 (5.06%) | 0.573 |
| Comorbidity | |||
| Hypertension | 150 (96.77%) | 154 (97.47%) | 0.748 |
| Diabetes mellitus | 60 (38.71%) | 58 (36.71%) | 0.804 |
| Cardiovascular disease | 55 (35.48%) | 72 (45.57%) | 0.089 |
| Chronic lung disease | 16 (10.32%) | 28 (17.72%) | 0.073 |
| Liver cirrhosis | 3 (1.94%) | 4 (2.53%) | 1.000 |
| Dementia | 1 (0.65%) | 4 (2.53%) | 0.371 |
| Cancer | 7 (4.52%) | 11 (6.96%) | 0.468 |
| Hyperlipidemia | 39 (25.16%) | 48 (30.38%) | 0.366 |
| PD related parameters | |||
| D/P Creatinine at 4 hours | 0.68 ± 0.12 | 0.68 ± 0.13 | 0.708 |
| Ultrafiltration (L/day) | 0.74 ± 0.06 | 0.86 ± 0.14 | 0.369 |
| 24 hrs urine volume (L) | 1.11 ± 0.65 | 0.85 ± 0.58 | <0.001* |
| Total Weekly Kt/V | 2.05 ± 0.51 | 1.95 ± 0.51 | 0.110 |
| nPNA (g/kg/day) | 0.98 ± 0.24 | 0.98 ± 0.28 | 0.940 |
| Residual renal function (mL/min/1.73 m2) | 3.42 ± 1.98 | 2.74 ± 1.87 | 0.002* |
| Laboratory data | |||
| RDW (%) | 14.37 ± 0.67 | 16.95 ± 1.74 | <0.001* |
| Serum albumin (g/L) | 34.1 ± 5.1 | 31.2 ± 5.7 | <0.001* |
| ALP (μkat/L) | 1.54 ± 1.03 | 1.85 ± 1.57 | 0.039* |
| BUN (mmol/L) | 28.20 ± 7.37 | 30.21 ± 8.25 | 0.024* |
| Creatinine (μmol/L) | 885.77 ± 240.45 | 843.34 ± 251.05 | 0.124 |
| Cholesterol (mmol/L) | 4.92 ± 1.23 | 4.62 ± 1.20 | 0.028* |
| Triglyceride (mmol/L) | 1.55 ± 0.77 | 1.39 ± 0.69 | 0.064 |
| Ferritin (ng/mL) | 297.43 ± 240.13 | 390.61 ± 406 | 0.014* |
| GPT (μkat/L) | 0.33 ± 0.31 | 0.36 ± 0.30 | 0.441 |
| Hemoglobin (g/L) | 90.1 ± 13.6 | 84.8 ± 10.9 | <0.001* |
| Intact PTH (pmol/L) | 43.81 ± 36.68 | 42.57 ± 31.98 | 0.750 |
| Calcium (mmol/L) | 2.12 ± 0.17 | 2.06 ± 0.19 | 0.006* |
| Phosphorus (mmol/L) | 1.74 ± 0.37 | 1.76 ± 0.45 | 0.756 |
| Transferrin Saturation (%) | 0.28 ± 0.13 | 0.27 ± 0.15 | 0.809 |
| WBC count (X10^9/L) | 7.32 ± 2.4 | 7.36 ± 2.33 | 0.892 |
| Calcium phosphate product (mmol2/L2) | 3.66 ± 0.83 | 3.55 ± 0.95 | 0.265 |
Values are expressed as mean ± SD or number (percentage).
Abbreviations: ACE inhibitor, angiotensin-converting enzyme inhibitor; ARB, angiotensin II receptor blocker; BMI, body mass index; GPT, glutamic-pyruvic transaminase; WBC, white blood cell count; PTH, parathyroid hormone; ALP, alkaline phosphate; BUN, blood urea nitrogen; RDW, red cell distribution width.
*p-value < 0.05.