Table 1.

Baseline characteristics of participants in the Synbiotics Easing Renal Failure by Improving Gut Microbiology Study who were randomized by treatment order (n=37)

CharacteristicAll Patients Randomized (n=37)Treatment Order 1 (n=17)aTreatment Order 2 (n=20)
Age, yr69±1068±1069±10
 Range43–8243–8250–82
Men21 (57)7 (41)14 (70)
White35 (95)16 (94)19 (95)
Cause of kidney disease
 GN5 (14)2 (12)3 (15)
 Hypertension/vascular7 (19)3 (18)4 (20)
 Diabetic nephropathy14 (38)9 (53)5 (25)
BMI, kg/m229±630±828±4
Comorbidities (treated)
 Hypertension37 (100)17 (100)20 (100)
 Hyperlipidemia29 (78)13 (76)16 (80)
No. of antihypertensive medications2.3±1.12.5±1.42.0±0.7
 Angiotensin–converting enzyme inhibitor8 (22)3 (18)5 (25)
 Angiotensin receptor II blocker22 (59)12 (71)10 (50)
 Diuretics13 (35)6(35)7 (35)
Smoking history20 (54)8 (47)12 (60)
EPI GFR, ml/min per 1.73 m224±824±925±7
Proteinuria, mg/24 h318 (165–1600)523 (160–1700)263 (168–1100)
Albuminuria, mg/24 h107 (20–1100)275 (18–1200)97 (20–677)
Uremic toxins (μmol/L)
 Total indoxyl sulfate18 (12–27)20 (16–27)15 (10–25)
 Total p-cresyl sulfate110 (71–130)128 (88–174)100 (61–119)
 Free indoxyl sulfate0.7 (0.4–1.0)0.8 (0.5–1.1)0.6 (0.3–0.9)
 Free p-cresyl sulfate3.0 (2.0–3.9)3.3 (2.0–5.2)2.5 (1.7–3.3)
Indoxyl sulfate-to-p-cresyl sulfate ratio0.23±0.170.19±0.110.27±0.22
Percentage free fraction
 Indoxyl sulfate4.1±1.54.4±1.83.8±1.0
 P-cresyl sulfate2.9±1.03.1±1.22.7±0.8
  • Data are presented as means±SDs, medians (interquartile ranges), or numbers (%). BMI, body mass index; EPI, epidemiology collaboration.

  • a The imbalance in numbers arose because of the spoiling of two randomized kits, which were replaced by the next available kits.