Potassium Intake in Patients With Chronic Kidney Disease - Full Text View

Sponsor:	Johns Hopkins University
Collaborator:	American Heart Association
Information provided by:	Johns Hopkins University
ClinicalTrials.gov Identifier:	NCT00949585

Purpose

Chronic kidney disease is associated with high blood pressure, heart disease, and strokes. Potassium lowers blood pressure and may help prevent heart disease and strokes in the general population, but has not been well-studied in people with kidney disease. This study will look at the benefits and safety of two levels of potassium intake in patients with kidney disease. We expect that a higher level of potassium intake safely lowers blood pressure compared to a lower level of potassium intake. We hope that this and other research projects will help us to learn more so that guidelines can be created for potassium intake in patients with chronic kidney disease

Condition	Intervention
Chronic Kidney Disease Blood Pressure	Other: Dietary intake of potassium

Study Type:	Interventional
Study Design:	Treatment, Randomized, Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Dose Comparison, Crossover Assignment, Safety/Efficacy Study
Official Title:	Potassium Intake in Patients With Chronic Kidney Disease

Resource links provided by NLM:

MedlinePlus related topics: Diets

Drug Information available for: Potassium chloride

U.S. FDA Resources

Further study details as provided by Johns Hopkins University:

Primary Outcome Measures:

24-hour ambulatory systolic blood pressure [ Time Frame: At screening, and at the end of each intervention period ] [ Designated as safety issue: Yes ]

Secondary Outcome Measures:

other measures of peripheral blood pressure (other types of ambulatory blood pressure measurements as well as clinic blood pressure) [ Time Frame: Ambulatory BP: same as primary outcome. Clinic BP: at screening, run-in, and weekly during intervention ] [ Designated as safety issue: Yes ]
measures of central blood pressure (pulse wave velocity and augmentation index) [ Time Frame: at screening and at the end of each intervention period ] [ Designated as safety issue: No ]
Serum potassium [ Time Frame: At screening, run-in, and at least 3 times during each intervention period ] [ Designated as safety issue: Yes ]
Serum inflammatory markers [ Time Frame: Before and and the end of each intervention period ] [ Designated as safety issue: No ]

Estimated Enrollment:	26
Study Start Date:	July 2009
Estimated Study Completion Date:	June 2012
Estimated Primary Completion Date:	June 2012 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
Dietary potassium intake: 100 mmol/day Participants will be given one of two diets: one contains 100 mmol of potassium per day, and the other contains 40 mmol of potassium per day	Other: Dietary intake of potassium Comparison of two diets: one contains 100 mmol potassium per day, and the other contains 40 mmol potassium per day
Dietary potassium intake: 40 mmol/day Diet containing 40 mmol/day of potassium	Other: Dietary intake of potassium Comparison of two diets: one contains 100 mmol potassium per day, and the other contains 40 mmol potassium per day

Detailed Description:

In individuals without chronic kidney disease (CKD), potassium (K) lowers blood pressure (BP) and may help prevent cardiovascular disease (CVD) and stroke. In animal models, K prevented kidney injury and decreased kidney inflammation. CKD patients may especially benefit from higher K intake, due to their high prevalence of hypertension, CVD, and stroke, and the possibility that K may retard CKD progression. Despite these potential benefits, there is great uncertainty about the optimal K intake in CKD patients. K is often restricted in these patients due to concerns about elevating serum K. However, renal K excretion does not appear to be substantially impaired until the glomerular filtration rate (GFR) is severely decreased (< 10-20 mL/min/1.73 m2). In this randomized feeding study with a two-period crossover design, the benefits and safety of 4 weeks of 100 mmol versus 40 mmol K/day in 26 non-diabetic adults with stage 3 CKD (estimated GFR 30-59 mL/min/1.73 m2) will be evaluated. After a one-week run-in period, all participants will be randomized to receive either a diet containing either 40 mmol K/day or 100 mmol K/day (within the current K/DOQI recommendations for K intake for stage 3 CKD) during period 1 (they will receive the other during period 2). The primary outcome variable is 24-hour ambulatory systolic BP. Secondary outcomes are other measures of peripheral BP, central BP, inflammatory markers, and serum K. We hope that this study will lead to a larger trial with sufficient power to examine the effects of increased K intake on clinical outcomes such as CKD progression. The ultimate goal of this effort is to develop the scientific basis for guidelines on K intake in CKD.

Eligibility

Ages Eligible for Study:	18 Years and older
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

Inclusion Criteria:

Stage 3 chronic kidney disease (estimated glomerular filtration rate 30-59 mL/min/1.73 m2 by the 4-variable Modification of Diet in Renal Disease (MDRD) Study Equation
Systolic blood pressure 120-159 mm Hg and diastolic blood pressure < 100 mm Hg
willingness to follow strict dietary rules for 9 weeks and to come to the clinical research unit at least 3 weekdays per week for one meal during the two study periods

Exclusion Criteria:

Baseline serum potassium of at least 5 mEq/L (or history of hyperkalemia)
Baseline serum potassium of less than 3.5 mEq/L (or history of hypokalemia)
Insulin-requiring or uncontrolled (HbA1C > 9 g/dL) diabetes mellitus
Use of potassium-sparing diuretics, potassium supplements, non-steroidal anti-inflammatory agents, steroids, digoxin, or calcineurin inhibitors
History of any organ transplant
Body mass index > 40 kg/m2
Chronic disease(s) that may interfere with trial participation
Pregnancy or lactation
> 14 alcoholic drinks/week
Major food allergies or intolerances

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00949585

Contacts

Contact: Sharon Turban, MD, MHS	410-281-1881	CKD@jhmi.edu
Contact: Charalett Diggs, BSN, RN	410-281-1881	CKD@jhmi.edu

Locations

United States, Maryland
Johns Hopkins University Pro Health Clinical Research Facility	Recruiting
Baltimore, Maryland, United States, 21207
Contact: Charalett Diggs 410-281-1881 CKD@jhmi.edu
Principal Investigator: Sharon Turban, MD, MHS
Sub-Investigator: Lawrence J. Appel, MD, MPH
Sub-Investigator: Edgar (Pete) R. Miller, 3rd, MD, PhD
Sub-Investigator: Cheryl A. Anderson, PhD, MPH, MS

Sponsors and Collaborators

Johns Hopkins University

American Heart Association

Investigators

Principal Investigator:

Sharon Turban, MD, MHS

Johns Hopkins University

More Information

No publications provided

Responsible Party:	Johns Hopkins University School of Medicine ( Sharon Turban, M.D., M.H.S. )
Study ID Numbers:	AHA 0835162N
Study First Received:	July 29, 2009
Last Updated:	July 29, 2009
ClinicalTrials.gov Identifier:	NCT00949585 History of Changes
Health Authority:	United States: Institutional Review Board

Keywords provided by Johns Hopkins University:

randomized, controlled feeding study;
crossover design
potassium intake

Additional relevant MeSH terms:

Renal Insufficiency
Urologic Diseases
Renal Insufficiency, Chronic

Kidney Failure, Chronic
Kidney Diseases
Kidney Failure

ClinicalTrials.gov processed this record on February 08, 2010