Table 1.

Baseline descriptive statistics by study site and treatment group (n=58)

VariableUniversity of MichiganUniversity of North Carolina at Chapel Hill
Group 1, n=17Group 2, n=20Group 1, n=12Group 2, n=9
Phase 1 dietSalt restrictedUsualSalt restrictedUsual
Demographics/anthropometrics
 Age, yr56.2±14.064.0±11.456.9±14.767.0±8.6
 Men47.1% (8)75.0% (15)58.3% (7)55.6% (5)
 Black11.8% (2)15.0% (3)66.7% (8)44.4% (4)
 Body mass index, kg/m233.7±6.631.8±4.829.8±5.133.1±6.8
CKD stage
 3a, eGFR≥45 ml/min per 1.73 m229.4% (5)40.0% (8)8.3% (1)33.3% (3)
 3b, eGFR<45 to ≤30 ml/min per 1.73 m235.3% (6)25.0% (5)50.0% (6)66.7% (6)
 4, eGFR<30 to ≤15 ml/min per 1.73 m235.3% (6)35.0% (7)41.7% (5)0.0% (0)
Cause of CKD
 Diabetes17.6% (3)40.0% (8)8.3% (1)11.1% (1)
 Hypertension35.3% (6)45.0% (9)25.0% (3)33.3% (3)
 Other29.4% (5)25.0% (5)50.0% (6)33.3% (3)
 Unknown11.8% (2)10.0% (2)33.3% (4)0.0% (0)
Comorbidities
 Diabetes41.2% (7)45.0% (9)33.3% (4)55.6% (5)
 Hypertension94.1% (16)95.0% (25)91.7% (11)88.9% (8)
 Cardiovascular disease23.5% (4)20.0% (4)16.7% (2)44.4% (4)
 Cancer17.6% (3)40.0% (8)0.0% (0)22.2% (2)
 Gastrointestinal disorders11.8% (2)0.0% (0)33.3% (4)44.4% (4)
 Hyperlipidemia35.3% (6)50.0% (10)41.7% (5)77.8% (7)
Average systolic BP (SBP)
 In-center standing SBP, mm/Hg128.4±17.1137.9±17.0129.8±18.8125.1±11.5
 In-center supine SBP, mm/Hg129.9±14.6139.5±19.1130.8±19.8126.1±7.6
 24-hour ambulatory SBP, mm/Hg142.7±21.8142.3±13.0133.4±13.8128.6±12.3
 24-hour ambulatory heart rate, bpm73.3±12.168.8±8.872.7±9.172.9±10.2
Volume statusa
 Edema (yes/no)29.4% (5)50.0% (10)16.7% (2)33.3% (3)
 Clinically euvolemic (yes/no)88.2% (15)65.0% (13)83.3% (10)87.5% (7)
 Clinically hypervolemic (yes/no)11.8% (2)35.0% (7)8.3% (1)12.5% (1)
Laboratory measurements (serum)
 Creatinine, mg/dl2.0±0.81.8±0.62.1±0.51.6±0.3
 eGFR, ml/min per 1.73 m236.4±11.940.5±13.634.5±9.343.4±8.2
 Sodium, mEq/L139.2±3.8140.2±2.4140.7±3.3141.3±2.6
 Potassium, mEq/L4.5±0.64.5±0.64.7±0.74.5±0.5
 Carbon dioxide, mEq/L27.2±2.628.0±2.624.4±3.327.4±3.4
 Glucose, mg/dlb108 (90, 137)105.0 (88.5, 145.5)101.5 (80.5, 127)149 (107, 202.8)
Laboratory measurements (urine)
 Albumin excretion, mg/24 hb69.2 (17.3, 442.1)116.5 (12.8, 720.5)143.5 (44.4, 200.8)42.8 (32.5, 102.3)
 Potassium, mmol/24 h60.6±24.959.2±23.469.0±37.573.7±25.5
 Creatinine, g/24 h1.3±0.41.5±0.31.7±0.61.5±0.4
 Sodium, mEq/24 h169.9±39.9167.3±48.1180.8±51.0167.6±55.9
 Albumin-to-creatinine ratio, mg/gb41.1 (12.0, 290.1)107.7 (14.2, 447.8)80.1 (13.9, 805.7)18.5 (11.1, 70.8)
  • Continuous variables are reported as mean±SD for normally distributed variables and as median (25th, 75th percentiles) for skewed variables. Categorical variables are reported as % (n).

  • a Volume status was evaluated by physical at initial evaluation. Patients were deemed clinically euvolemic if there was no jugular venous pressure elevation, pulmonary rales, and peripheral and/or sacral edema.

  • b Median (25th, 75th percentiles) reported for skewed variables.