Table 2.
Characteristics of participants by quartiles of pre-systolic blood pressure
| Total N = 314 | Pre SBP, Q1 N = 77 | Pre SBP, Q2 N = 80 | Pre SBP, Q3 N = 80 | Pre SBP, Q4 N = 77 | Trend P-value | ||
|---|---|---|---|---|---|---|---|
| Age (years) | 63 ± 16 | 65 ± 14 | 64 ± 18 | 61 ± 17 | 63 ± 16 | 0.42 | |
| Female (%) | 47 | 39 | 43 | 44 | 61 | 0.01 | |
| African American (%) | 22 | 17 | 26 | 20 | 26 | 0.33 | |
| Education (%) | <12th grade | 10 | 13 | 10 | 9 | 8 | 0.51 |
| High school graduate | 55 | 47 | 60 | 59 | 53 | ||
| 2+ Years college | 35 | 40 | 30 | 33 | 39 | ||
| Medical History (%) | Stroke | 18 | 14 | 25 | 9 | 23 | 0.60 |
| PVD | 24 | 30 | 23 | 24 | 18 | 0.12 | |
| CAD | 37 | 47 | 38 | 33 | 31 | 0.04 | |
| Hypertension | 89 | 81 | 90 | 91 | 95 | 0.01 | |
| Diabetes | 48 | 43 | 53 | 44 | 52 | 0.48 | |
| Heart Failure | 36 | 43 | 34 | 29 | 39 | 0.49 | |
| Primary cause of ESRD (%) | Diabetes | 36 | 33 | 40 | 32 | 41 | 0.18 |
| Glomerulonephritis | 19 | 26 | 16 | 24 | 9 | ||
| Hypertension | 20 | 14 | 21 | 14 | 29 | ||
| Other | 17 | 16 | 17 | 22 | 13 | ||
| Unknown | 8 | 11 | 5 | 9 | 8 | ||
| Smoking History (%) | Never | 38 | 32 | 29 | 44 | 48 | 0.05 |
| Past | 53 | 59 | 59 | 47 | 45 | ||
| Current | 9 | 8 | 12 | 9 | 7 | ||
| Monthly Pre Systolic BP (mm Hg) | 141 ± 21 | 115 ± 10 | 135 ± 4 | 148 ± 4 | 168 ± 12 | <0.01 | |
| Monthly Diastolic BP (mm Hg) | 73 ± 12 | 62 ± 9 | 70 ± 8 | 76 ± 9 | 84 ± 11 | <0.01 | |
| Monthly Pulse Pressure (mm Hg) | 68 ± 15 | 53 ± 9 | 64 ± 8 | 72 ± 10 | 84 ± 11 | <0.01 | |
| Intradialytic Blood Pressure (mm Hg) | −10 ± 24 | −3 ± 19 | −7 ± 20 | −12 ± 23 | −18 ± 29 | <0.01 | |
| Intradialytic Weight Gain (kg) | 2.6 ± 1.1 | 2.7 ± 0.9 | 2.7 ± 1.2 | 2.6 ± 1.1 | 2.4 ± 1.1 | 0.03 | |
| Body Mass Index (kg/m2) | 28 ± 7 | 28 ± 6 | 29 ± 7 | 28 ± 7 | 29 ± 8 | 0.51 | |
| Hematocrit (%) | 36 ± 4 | 35 ± 4 | 36 ± 4 | 35 ± 4 | 36 ± 3 | 0.65 | |
| Serum Albumin (g/dL) | 3.8 ± 0.4 | 3.6 ± 0.4 | 3.8 ± 0.3 | 3.9 ± 0.4 | 3.9 ± 0.4 | <0.01 | |
| Phosphate (mg/dL) | 5.5 ± 1.5 | 5.5 ± 1.5 | 5.5 ± 1.8 | 5.5 ± 1.4 | 5.4 ± 1.4 | 0.57 | |
| Dialysis Vintage (months) | 14 (7–35) | 18 (7–40) | 13 (5–33) | 15 (8–34) | 15 (7–27) | 0.61 | |
| Parathyroid Hormone (pg/ml) | 228 (145–396) | 216 (148–403) | 239 (146–427) | 220 (121–336) | 249 (163–388) | 0.86 | |
| spKt/V | 1.51 ± 0.24 | 1.52 ± 0.26 | 1.49 ± 0.23 | 1.52 ± 0.25 | 1.53 ± 0.22 | 0.68 | |
Continuous data shown are mean ± standard deviation except dialysis vintage and parathyroid hormone which are median (interquartile range); categorical data are presented as percentage. P-values for education primary cause of ESRD and smoking are from Chi-square test. P-values for dialysis vintage and PTH are from Kruskal-Wallis test. Conversion factors for units: albumin in g/dL to g/L, multiply by 10; phosphate in mg/dL to mmol/L, multiply by 0.3229.
*Abbreviations: PVD, peripheral vascular disease; CAD, coronary artery disease; ESRD, End-Stage Renal Disease; SBP, systolic blood pressure