NCT02458248

Brief Summary

Chronic kidney disease, which affects an estimated 300,000 people in Ireland and over 50 million people in the developed world, is responsible for a considerable burden of premature mortality and morbidity. All patients with chronic kidney disease are recommended low salt diets, i.e. less than a teaspoon of salt per day (which is \<5-6g of salt, which contains \<2-2.3g of sodium). The average intake in the general population is double the recommended intake, between 1-2 teaspoons per day, which is considered 'moderate' intake. In patients with hypertension, reducing from moderate (average) to low intake is associated with a small reduction in blood pressure. However, achieving this low target salt intake is difficult, and can have a negative knock-on effect on other healthy dietary factors and kidney hormones. In addition, there is no convincing research to show that patients with chronic kidney disease and normal blood pressure benefit from low salt intake. In fact, the small amount of research that does exist shows that the change in kidney function is the same in people who consume low salt diets (\<1 teaspoon) and moderate (1-2 teaspoons=average intake) salt diets. Moreover, there are some small studies that report that low-salt diets may increase the risk of death due to heart disease. Given that all patients with chronic kidney impairment are recommended a low-salt diet, it is important that we confirm that this recommendation truly benefits patients. In this randomized controlled trial, we hope to determine whether recommending a low salt intake, compared to average/moderate intake, is associated with a slower rate of decline in kidney function in patients with chronic kidney impairment. The results of this study will provide information to guide future research that will have critical implications for management of patients with chronic kidney disease.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
105

participants targeted

Target at P50-P75 for phase_2

Timeline
Completed

Started Mar 2016

Typical duration for phase_2

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

May 15, 2015

Completed
17 days until next milestone

First Posted

Study publicly available on registry

June 1, 2015

Completed
9 months until next milestone

Study Start

First participant enrolled

March 1, 2016

Completed
4.4 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

August 1, 2020

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

August 1, 2020

Completed
Last Updated

April 28, 2021

Status Verified

April 1, 2021

Enrollment Period

4.4 years

First QC Date

May 15, 2015

Last Update Submit

April 27, 2021

Conditions

Keywords

Chronic Kidney DiseaseSodium ReductioneGFR 30-60ml/min/1.73m2

Outcome Measures

Primary Outcomes (1)

  • Change in 24-hour urinary creatinine clearance from baseline to final follow-up, measured from 24-hour urinary collection and corresponding serum creatinine measurement at randomisation and final visit.

    24 months

Secondary Outcomes (9)

  • Change in eGFR (MDRD formula) from baseline to final follow-up

    24 months

  • Change in eGFR (CKD-EPI formula) from baseline to final follow-up

    24 months

  • Rates of requirement for renal replacement therapy

    24 months

  • Change in 24-hour urinary protein from baseline to final visit

    24 months

  • Increase in risk category for prognosis of CKD as measured by the KDIGO 2012 CKD classification table

    24 months

  • +4 more secondary outcomes

Study Arms (2)

Sodium Reduction

EXPERIMENTAL

In addition to usual care, those randomised to the intervention arm will receive specific counseling on behavioural and environmental factors that promote sodium reduction after randomization and at all post-randomisation visits, targeting sodium intake of \<100mmol/day (\<2.3g/day).

Behavioral: Sodium Reduction

Usual care

NO INTERVENTION

For all participants, standard care will be provided at the nephrology clinic at GUH or by local general practitioners, and includes treatment of hypertension, underlying comorbidities and optimizing the metabolic profile. Participants randomized to usual care will also attend a dietitian-developed healthy eating guidance session but will not receive specific recommendations targeting sodium intake.

Interventions

In addition to usual care, those randomised to the intervention arm will receive specific counseling on behavioural and environmental factors that promote sodium reduction after randomization and at all specified post-randomisation visits, targeting sodium intake of \<100mmol/day (\<2.3g/day). A research dietitian will develop the specific components of the intervention, based on standardised approaches to education interventions.

Sodium Reduction

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Age 40 years or older
  • MDRD eGFR of 30-60ml/min/1.73m2 on ≥2 occasions ≥3 months apart
  • Most recent eGFR measurement within 3 months Systolic blood pressure \<160mmHg and diastolic blood pressure \<95mmHg on three office blood pressure readings at time of screening and confirmed by a study ABPM before randomisation of \<150/90mmHg
  • No change in anti-hypertensive or diuretic medications (including dose) for 3 months before screening visit
  • Consumption of moderate sodium intake at screening, defined as an estimated daily sodium intake of \>2.3g/day estimated from food frequency questionnaire (FFQ) completed during the screening visit
  • Self-reported willingness to modify dietary intake over sustained period, and adhere to directed recommendations over 2 years
  • Signed written informed consent

You may not qualify if:

  • Acute Kidney Injury in the preceding three months, defined as doubling of baseline serum creatinine or rapidly declining eGFR over the preceding six months, defined as a decline in eGFR of ≥10ml/min/1.73m2 in those with established CKD
  • Any of the following renal conditions: glomerular disease due to post-infectious glomerulonephritis, IgA nephropathy, thin basement membrane disease, Henoch-Schonlein purpura, proliferative glomerulonephritis, membranous nephropathy (including lupus nephritis), rapidly progressive glomerulonephritis, minimal change disease, or focal segmental glomerulosclerosis
  • Prior or planned renal transplantation
  • Prior, current or planned renal dialysis
  • Medical diagnosis known to be associated with abnormal renal sodium excretion, including Bartter syndrome, SIADH, diabetes insipidus, or serum sodium \<125mmol
  • Severe heart failure (defined as left ventricular ejection fraction ≤30% or NYHA Class III/IV symptoms)
  • High-dose loop or thiazide diuretic therapy, exceeding a total daily dose of frusemide 80mg, bumetanide 2mg, hydrochlorothiazide 50mg, bendroflumethiazide 2.5mg, indapamide 2.5mg, metolazone 2.5mg or the use of both a loop and thiazide diuretic
  • Unable to follow educational advice of the research team
  • Prescribed high-salt diet, low-salt diet or sodium bicarbonate
  • Symptomatic postural hypotension or receiving treatment for postural hypotension
  • Current or recent use (within one month) of immunosuppressive medications including tacrolimus, cyclosporine, azathioprine or mycophenolate mofetil
  • Pregnancy or lactation
  • Unable to comply with 24-hour urinary collections, or medical condition making collection of 24-hour urinary collection difficult (e.g. severe urinary incontinence)
  • Participant unlikely to comply with study procedures or follow-up visits due to severe co-morbid illness or other factor (e.g. inability to travel for follow-up visits, drug or alcohol misuse) in opinion of research team
  • Cognitive impairment defined as a known diagnosis of dementia, or inability to provide informed consent due to cognitive impairment in the opinion of the investigator
  • +2 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

HRB Clinical Research Facility Galway

Galway, Ireland

Location

Related Publications (3)

  • Smyth A, Judge C, Kerins C, McDermott S, Niland A, Corcoran C, Dineen R, Alvarez-Iglesias A, Nolan A, Mente A, Griffin MD, O'Shea P, Canavan M, Yusuf S, O'Donnell M. Dietary counselling to reduce moderate sodium intake: effects on cardiovascular and renal biomarkers: primary findings of the COSIP and STICK phase II feasibility randomised controlled trials. EClinicalMedicine. 2023 Feb 15;57:101856. doi: 10.1016/j.eclinm.2023.101856. eCollection 2023 Mar.

  • Smyth A, Yusuf S, Kerins C, Corcoran C, Dineen R, Alvarez-Iglesias A, Ferguson J, McDermott S, Hernon O, Ranjan R, Nolan A, Griffin M, O'Shea P, Canavan M, O'Donnell M. Clarifying Optimal Sodium InTake In Cardiovasular and Kidney (COSTICK) Diseases: a study protocol for two randomised controlled trials. HRB Open Res. 2022 Feb 7;4:14. doi: 10.12688/hrbopenres.13210.2. eCollection 2021.

  • McMahon EJ, Campbell KL, Bauer JD, Mudge DW, Kelly JT. Altered dietary salt intake for people with chronic kidney disease. Cochrane Database Syst Rev. 2021 Jun 24;6(6):CD010070. doi: 10.1002/14651858.CD010070.pub3.

MeSH Terms

Conditions

Kidney DiseasesRenal Insufficiency, ChronicRenal Insufficiency

Condition Hierarchy (Ancestors)

Urologic DiseasesFemale Urogenital DiseasesFemale Urogenital Diseases and Pregnancy ComplicationsUrogenital DiseasesMale Urogenital DiseasesChronic DiseaseDisease AttributesPathologic ProcessesPathological Conditions, Signs and Symptoms

Study Officials

  • Martin J O'Donnell, MB PhD MRCPI

    National University of Ireland, Galway

    PRINCIPAL INVESTIGATOR
  • Andrew Smyth, MB PhD

    National University of Ireland, Galway

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
phase 2
Allocation
RANDOMIZED
Masking
NONE
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Dr.

Study Record Dates

First Submitted

May 15, 2015

First Posted

June 1, 2015

Study Start

March 1, 2016

Primary Completion

August 1, 2020

Study Completion

August 1, 2020

Last Updated

April 28, 2021

Record last verified: 2021-04

Locations