Table 1.
Study cohort characteristics
| All (n = 50) | RLS (n = 14) | No RLS (n = 36) | P-value | |
|---|---|---|---|---|
| Age, mean (SD), years | 64 (12.4) | 60.9 (12.0) | 62.2 (12.5) | 0.28 |
| Gender, n (%) | 0.007 | |||
| Male | 26 (52) | 3 (21.4) | 23 (63.9) | |
| Female | 24 (48) | 11 (78.6) | 13 (36.1) | |
| Dialysis treatments, n (%) | 0.74 | |||
| Two times weekly | 2 (4) | 1 (7.1) | 1 (2.8) | |
| Three or more times weekly | 48 (96) | 13 (92.9) | 35 (97.2) | |
| Duration of HD, mean (SD), h | 3.6 (0.4) | 3.6 (0.48) | 3.6 (0.43) | 0.92 |
| Vascular access, n (%) | 0.30 | |||
| Fistula | 24 (48) | 9 (64.3) | 15 (41.7) | |
| Graft | 3 (6) | 1 (7.1) | 2 (5.6) | |
| Catheter | 23 (46) | 4 (28.6) | 19 (52.8) | |
| URR, mean (SD), % | 69.5 (6.2) | 72.1 (5.2) | 68.5 (6.3) | 0.07 |
| Etiology of ESRD, n (%) | 0.019 | |||
| DN | 19 (38) | 5 (35.7) | 14 (38.9) | |
| HTN | 4 (8) | 1 (7.1) | 3 (8.3) | |
| GN | 12 (24) | 5 (35.7) | 7 (19.4) | |
| Other | 15 (30) | 3 (21.4) | 12 (33.3) | |
| Comorbidities, n (%) | ||||
| Diabetes | 24 (48) | 7 (50.0) | 17 (47.2) | 0.86 |
| CAD | 13 (26) | 2 (14.3) | 11 (30.6) | 0.24 |
| PVD | 9 (18) | 1 (7.1) | 8 (22.2) | 0.21 |
| CVD | 10 (20) | 1 (7.1) | 9 (25.0) | 0.16 |
| OSA | 11 (22) | 3 (21.4) | 8 (22.2) | 0.95 |
| Dopamine, n (%) | 1 (2) | 0 (0) | 1 (2.7) | 0.53 |
| Dopamine agonist, n (%) | 2 (4) | 1 (7.1) | 1 (2.7) | 0.48 |
| Alpha 2 delta ligand, n (%) | 9 (18) | 2 (14.3) | 7 (19.4) | 0.18 |
| Hemoglobin, mean (SD), g/dL | 10.6 (0.99) | 10.4 (1.0) | 10.6 (0.99) | 0.50 |
| Serum iron, mean (SD), g/dL | 11.0 (2.7) | 10.3 (2.5) | 11.2 (2.8) | 0.28 |
| TIBC, mean (SD), μmol/L | 31.5 (6.2) | 35.9 (6.1) | 34.8 (6.3) | 0.59 |
| Transferrin saturation, mean (SD), % | 32.2 (10.6) | 29.7 (10.0) | 33.2 (10.7) | 0.30 |
| Ferritin, mean (SD), μmol/L | 724 (654) | 959 (1083) | 632 (362) | 0.11 |
| Calcium, mean (SD), mmol/L | 2.28 (0.2) | 2.33 (0.24) | 2.26 (0.17) | 0.26 |
| Phosphate, mean (SD), mmol/L | 1.72 (0.5) | 1.82 (0.49) | 1.69 (0.57) | 0.46 |
| Albumin, mean (SD), g/L | 31.5 (2.8) | 32 (2.3) | 31 (3.0) | 0.30 |
| PTH, mean (SD), pmol/L | 60.3 (42.2) | 72.1 (51.7) | 55.8 (37.8) | 0.22 |
P-value is for the comparison of RLS versus no RLS.
HD, hemodialysis; URR, urea reduction ratio; DN, diabetic nephropathy; HTN, hypertension; GN, glomerulonephritis; CAD, coronary artery disease; PVD, peripheral vascular disease; CVD, cerebrovascular disease; OSA, obstructive sleep apnea; TIBC, total iron binding capacity; PTH, parathyroid hormone.