Table 1.
Characteristics of the study population by hypertension classification as defined by median midweek intradialytic BP
| SN | WCH | MHTN | SHTN | Total | P | |
|---|---|---|---|---|---|---|
| n | 123 (35%) | 52 (15%) | 54 (15%) | 124 (35%) | 353 (100%) | |
| Men | 82 (67%) | 32 (62%) | 38 (70%) | 76 (61%) | 228 (65%) | 0.61 |
| Race | 0.03 | |||||
| nonblack | 14 (11%) | 5 (10%) | 15 (28%) | 21 (17%) | 55 (16%) | |
| black | 109 (89%) | 47 (90%) | 39 (72%) | 103 (83%) | 298 (84%) | |
| Age (years) | 55.7 ± 14.0 | 55.6 ± 12.5 | 56.5 ± 13.3 | 54.1 ± 11.7 | 55.2 ± 12.9 | 0.63 |
| Body mass index (kg/m2) | 28.4 ± 5.8 | 28.8 ± 7.3 | 26.5 ± 5.8 | 27.1 ± 5.4 | 27.7 ± 5.9 | 0.07 |
| Etiology of end-stage renal disease | 0.20 | |||||
| diabetes mellitus | 41 (33%) | 21 (40%) | 24 (44%) | 45 (36%) | 131 (37%) | |
| hypertensive nephrosclerosis | 57 (46%) | 23 (44%) | 21 (39%) | 51 (41%) | 152 (43%) | |
| glomerulonephritis | 9 (7%) | 0 (0%) | 0 (0%) | 11 (9%) | 20 (6%) | |
| adult autosomal polycystic kidney disease | 1 (1%) | 1 (2%) | 0 (0%) | 3 (2%) | 5 (1%) | |
| other/unknown | 9 (7%) | 4 (8%) | 8 (15%) | 9 (7%) | 30 (8%) | |
| Years on dialysis | 4.7 ± 4.9 | 2.9 ± 2.6 | 3.7 ± 4.6 | 3.0 ± 3.4 | 3.7 ± 4.1 | <0.01 |
| History of smoking | 0.55 | |||||
| current | 33 (27%) | 14 (27%) | 13 (24%) | 45 (36%) | 105 (30%) | |
| past | 46 (37%) | 17 (33%) | 18 (33%) | 41 (33%) | 122 (35%) | |
| never | 41 (33%) | 16 (31%) | 22 (41%) | 37 (30%) | 116 (33%) | |
| History of diabetes mellitus | 54 (44%) | 26 (50%) | 33 (61%) | 61 (49%) | 174 (49%) | 0.22 |
| History of cardiovascular disease | 40 (33%) | 21 (40%) | 22 (41%) | 42 (34%) | 125 (35%) | 0.62 |
| Urea reduction ratio (%) | 73.9 ± 7.8 | 73.6 ± 8.4 | 74.3 ± 6.3 | 74.4 ± 7.4 | 74.1 ± 7.5 | 0.97 |
| Albumin (g/dl) | 3.7 ± 0.4 | 3.8 ± 0.4 | 3.7 ± 0.4 | 3.7 ± 0.5 | 3.7 ± 0.4 | 0.10 |
| Hemoglobin (g/dl) | 12.3 ± 1.6 | 12.3 ± 1.5 | 12.2 ± 1.5 | 11.9 ± 1.4 | 12.2 ± 1.5 | 0.22 |
| On antihypertensive medications | 77 (63%) | 41 (79%) | 48 (89%) | 102 (82%) | 268 (76%) | <0.01 |
| Number of antihypertensives in users | 1.3 ± 1.3 | 1.9 ± 1.4 | 2.5 ± 1.6 | 2.3 ± 1.6 | 1.9 ± 1.6 | <0.01 |
| β-blocker | 66 (54%) | 33 (63%) | 37 (69%) | 88 (71%) | 224 (63%) | 0.03 |
| ACE inhibitor | 38 (31%) | 16 (31%) | 29 (54%) | 64 (52%) | 147 (42%) | <0.01 |
| ARB | 8 (7%) | 6 (12%) | 9 (17%) | 16 (13%) | 39 (11%) | 0.21 |
| α-blocker | 4 (3%) | 5 (10%) | 4 (7%) | 10 (8%) | 23 (7%) | 0.31 |
| dihydropyridine calcium-channel blocker | 29 (24%) | 21 (40%) | 29 (54%) | 64 (52%) | 143 (41%) | <0.01 |
| non-dihydropyridine calcium-channel blocker | 2 (2%) | 2 (4%) | 4 (7%) | 6 (5%) | 14 (4%) | 0.30 |
| vasodilator | 19 (15%) | 7 (13%) | 12 (22%) | 17 (14%) | 55 (16%) | 0.45 |
| centrally acting agents | 15 (12%) | 15 (29%) | 15 (28%) | 40 (32%) | 85 (24%) | <0.01 |
| Interdialytic weight gain (kg) | 2.9 ± 1.2 | 2.7 ± 1.2 | 2.8 ± 1.2 | 2.7 ± 1.3 | 2.8 ± 1.2 | 0.87 |
SN, sustained normotension; WCH, white-coat hypertension; MHTN, masked hypertension; SHTN, sustained hypertension; ACE, angiotensin-converting enzyme; ARB, angiotensin receptor blocker.