None listed
Conditions
Brief summary
Cardiovascular disease (CVD) is the leading cause of mortality in the chronic kidney disease (CKD) population, and is independently associated with kidney function decline. Dietary sodium intake has been implicated in several traditional and novel risk factors driving both CVD and CKD progression. Despite evidence implicating dietary sodium in the pathogenesis of CVD in CKD, sodium intake in CKD patients remains high and evidence suggests that sodium restriction is not adequately emphasized for CKD patients. Part of the reason for this may be high-quality intervention trials of sodium restriction in CKD patients are lacking. Most evidence has been extrapolated from studies in non-CKD populations. However, as sodium handling is influenced by kidney function; it is highly likely that the CKD population is more susceptible to adverse effects of high dietary sodium. The aim of this study is to examine the effect of reducing sodium intake on blood pressure, progression of renal failure and other cardiovascular risk factors in patients with moderate CKD.
Interventions
This will be a 2 phase study with phase 1 encompassing a randomised, controlled, double-blinded cross-over trial, and phase 2 involving long-term follow up to six months.
Trial periods:
Phase 1:
1) Run-in (washout) period: 1 week.
All participants will begin the trial consuming a low sodium diet (containing less than 60 mmol sodium per day).
2) First intervention period: 2 week.
All participants will continue on a low sodium diet but will be randomised to receive either sodium capsules (12
This will be a 2 phase study with phase 1 encompassing a randomised, controlled, double-blinded cross-over trial, and phase 2 involving long-term follow up to six months. Trial periods: Phase 1: 1) Run-in (washout) period: 1 week. All participants will begin the trial consuming a low sodium diet (containing less than 60 mmol sodium per day). 2) First intervention period: 2 week. All participants will continue on a low sodium diet but will be randomised to receive either sodium capsules (120 mmol of sodium chloride per day, resulting in a total target intake of 180 mmol per day) or placebo capsules (sodium consumed via diet only resulting in a total sodium intake of 60 mmol per day). 3) Washout period: 1 week. Participants will continue on a low sodium diet as per 1) above 4) Second intervention period: 2 week. Participants will crossover to the other tablets as per 2) above. The order of the two interventions (low sodium intake; moderate sodium intake) will be randomised. Neither the participants nor the investigators will be aware of the treatment order. Sodium restriction to 60 mmol per day will be facilitated by dietary education from the study dietitians with the aim to replace sodium-rich foods with lower sodium alternatives, and partial provision of food including pre-prepared meals, snack foods, spreads and sauces. Participants will have minimum fortnightly contact with the study dietitians (approximately 1 hour) to verify their dietary history forms and provide dietary education. Phase 2: 20 weeks Phase 2 will not include a control group; All phase 1 participants will continue on a low salt diet (goal < 100 mmol / day) to assess the translation of phase 1 results into a practical setting and to examine long-term adherence to a low salt diet. Sodium restriction to < 100 mmol per day will be facilitated by continued dietary education from the study dietitians by minimum monthly phone calls. Follow up measurements will occur at 4 months and 6 months (from baseline)
Sponsors
Princess Alexandra Hospital
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Prevention
Masking
Blinded (masking used) (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
- CKD stage 3 or 4 (GFR 15-59 ml/min/1.73m2) patients under the care of a nephrologist at the Princess Alexandra Hospital - Aged at least 18 years - Able to provide informed consent - Systolic BP 130-169 mmHg - Diastolic BP >70 mmHg.
Exclusion criteria
- Unable or unwilling to attend the PAH for visits as specified by the study protocol - Receiving renal replacement therapy (dialysis or transplant) or likely to within the trial duration - Salt-wasting CKD (as diagnosed by nephrologist) - Prescribed > 1680 mg of sodium bicarbonate and not able to cease this medication for six weeks - Pregnant or breastfeeding - Life expectancy less than 6 months. - Current involvement in other intervention - Unable to comprehend study protocol
Outcome results
None listed