Prebiotic Supplementation in Kidney Transplant Recipients for Preventing Infections and Gastrointestinal Upset: A Randomized Controlled Feasibility Study.

OBJECTIVES: Modulating the large intestinal microbiome of kidney transplant recipients (KTRs) may reduce infectious complications. The aim of this study is to assess the feasibility of a randomized controlled trial of prebiotics in reducing infections and gastrointestinal symptoms in KTRs. (DESIGN) AND METHODS: Acute KTRs were recruited to a double-blind, placebo-controlled, randomized trial at a single kidney transplant center. Patients were provided with prebiotics or placebo for 7 weeks. The primary outcome was feasibility, defined as recruitment of ≥80% of eligible people within 6 months. Secondary outcomes included adherence and tolerability, participant retention in trial, proportions of participants providing serum and stool specimens, self-reported quality of life, gastrointestinal symptoms, and infection events. RESULTS: During the 7-week period, 72 patients met eligibility criteria, of whom 60 (83%) consented to participate (mean ± standard deviation age 53 ± 12 years; 62% males). Fifty-six (78%) participants were randomized (27 interventions and 29 controls). Although participants receiving intervention experienced reduced gastrointestinal symptoms (-0.28 [interquartile range, IQR -0.67 to 0.08] vs. -0.07 [IQR -0.27 to 0], P = .03), both control and intervention groups were similar in adherence (67% vs. 72%, P = .36), tolerability (56% vs. 62%, P = .64), quality of life (-0.2 [IQR -0.6 to 0] vs. -0.2 [IQR -0.8 to 0], P = .82), and infection events (33% vs. 34%, P = .83). Blood and stool samples were collected from ≥90% of participants in both groups. CONCLUSIONS: It is feasible to recruit and retain acute KTRs in a randomized, placebo-controlled trial examining the effect of prebiotics on infections and gastrointestinal symptoms. This study also showed that prebiotics significantly reduced gastrointestinal symptoms.

PREBIOTIC: a study protocol of a randomised controlled trial to assess prebiotic supplementation in kidney transplant recipients for preventing infections and gastrointestinal upset - a feasibility study.

BACKGROUND: Modulating the microbiota in the large intestine of kidney transplant recipients through prebiotic supplementation may prevent infectious complications from occurring. To date, there have been no interventional trials which have investigated this novel treatment in kidney transplantation. The aim of PREBIOTIC is to assess the feasibility of performing a randomised controlled trial of prebiotics in reducing infections and gastrointestinal symptoms in kidney transplant recipients. METHODS: Sixty kidney transplant patients will be recruited to a double-blind, placebo-controlled, randomised feasibility trial. Patients will be provided with prebiotic therapy or placebo for 4 to 6 weeks. Outcomes will include recruitment, adherence, tolerance, retention, laboratory parameters (including serum indoxyl sulphate, ρ-cresyl sulphate and stool collection), patients' self-assessed quality of life, gastrointestinal symptoms and clinical outcomes. DISCUSSION: This trial will assess the feasibility of prebiotic supplementation in kidney transplant recipients. Prebiotics not only may alter the gut microbiota and their inherent metabolism and production of uraemic toxins but also may prevent infections from occurring in kidney transplant recipients. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry number ACTRN12618001057279p. The date of registration was 25th June 2018, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=375370&isReview=true .

The effect of lowering salt intake on ambulatory blood pressure to reduce cardiovascular risk in chronic kidney disease (LowSALT CKD study): protocol of a randomized trial.

BACKGROUND: Despite evidence implicating dietary sodium in the pathogenesis of cardiovascular disease (CVD) in chronic kidney disease (CKD), quality intervention trials in CKD patients are lacking. This study aims to investigate the effect of reducing sodium intake on blood pressure, risk factors for progression of CKD and other cardiovascular risk factors in CKD. METHODS/DESIGN: The LowSALT CKD study is a six week randomized-crossover trial assessing the effect of a moderate (180 mmol/day) compared with a low (60 mmol/day) sodium intake on cardiovascular risk factors and risk factors for kidney function decline in mild-moderate CKD (stage III-IV). The primary outcome of interest is 24-hour ambulatory blood pressure, with secondary outcomes including arterial stiffness (pulse wave velocity), proteinuria and fluid status. The randomized crossover trial (Phase 1) is supported by an ancillary trial (Phase 2) of longitudinal-observational design to assess the longer term effectiveness of sodium restriction. Phase 2 will continue measurement of outcomes as per Phase 1, with the addition of patient-centered outcomes, such as dietary adherence to sodium restriction (degree of adherence and barriers/enablers), quality of life and taste assessment. DISCUSSION: The LowSALT CKD study is an investigator-initiated study specifically designed to assess the proof-of-concept and efficacy of sodium restriction in patients with established CKD. Phase 2 will assess the longer term effectiveness of sodium restriction in the same participants, enhancing the translation of Phase 1 results into practice. This trial will provide much-needed insight into sodium restriction as a treatment option to reduce risk of CVD and CKD progression in CKD patients. TRIAL REGISTRATION: Universal Trial Number: U1111-1125-2149. Australian New Zealand Clinical Trials Registry Number: ACTRN12611001097932.

Evaluation of dietetic advice for modification of cardiovascular disease risk factors in renal transplant recipients.

OBJECTIVE: To investigate the effect of dietitian involvement in a multidisciplinary lifestyle intervention comparing risk factor modification for cardiovascular disease with standard posttransplant care in renal transplant recipients (RTR) with abnormal glucose tolerance (AGT). DESIGN: Randomized controlled trial. SETTING: Hospital outpatient department. PATIENTS: Adult RTR with AGT. INTERVENTION: RTR with AGT were randomized to a lifestyle intervention that consisted of either regular consultations with the dietitian and multidisciplinary team or standard care. MAIN OUTCOME MEASURES: Dietary intake, physical activity (PA) levels, cardiorespiratory fitness (CF), and anthropometry. RESULTS: Total fat and percent saturated fat intake rates were significantly lower in the intervention group as compared with the control group at 2-year follow-up, 54 g (16 to 105 g) versus 65 g (34 to 118 g), P = .01 and 10% (5% to 17%) versus 13% (4% to 20%), P = .05., respectively. There was a trend for an overweight (but not obese) individual to lose more weight in the intervention group (4% loss vs. a gain of 0.25% at the 2-year follow-up). Overall, RTR were significantly less fit than age- and gender-matched controls, mean peak oxygen uptake was 19.42 ± 7.09 mL/kg per minute versus 28.35 ± 8.80 mL/kg per minute, P = .000. Simple exercise advice was not associated with any improvement in total PA or CF in either group at the 2-year follow-up. CONCLUSION: Dietary advice can contribute to healthier eating habits and a trend for weight loss in RTR with AGT. These improvements in conjunction with multidisciplinary care and pharmacological treatment can lead to improvements in cardiovascular risk factors such as lipid profile. Simple advice to increase PA was not effective in improving CF and other measures are needed.