Clinical trial NCT04995627: Salt Supplementation in Gitelman Syndrome
Official title: Exploratory Study Into the Effect of Salt Supplementation in Gitelman Syndrome
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Gitelman Syndrome
Lead sponsor: Radboud University Medical Center
Sponsor class: OTHER
Collaborators: name: Dutch Kidney Foundation
First posted: 2021-08-09
Enrollment: 21
Sex: ALL
Minimum age (years): 16
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Single subject multiple randomized double-blinded multi-crossover placebo-controlled trials (N-of-1 trials)
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to determine the effect of salt (NaCl) supplementation on serum potassium and clinical signs and symptoms in patients with Gitelman syndrome.

Detailed description: Single subject multiple randomized double-blinded multi-crossover placebo-controlled trials (N-of-1 trials) will be performed. Participants will enroll the study after giving written informed consent. The individual trials will consist of 3 treatment blocks which each contain a 4-week treatment period of salt supplementation (12 grams of NaCl) and a 4-week treatment period of placebo, in a randomized, blinded order. After each period of 4 weeks, outcomes measures will be measured.

Eligibility criteria: Inclusion Criteria:

* Genetically-proven, symptomatic Gitelman syndrome
* Written informed consent

Exclusion Criteria:

* inability to discontinue potassium-sparing diuretics, mineralocorticoid antagonists and NSAIDs; this means inability to reach a potassium level of 2.5 mmol/L or higher with maximally tolerable potassium supplementation after discontinuation of potassium-sparing diuretics
* pregnancy

Primary outcomes:
measure: Change in serum Potassium
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in symptoms measured by personalized symptom score sheet
timeFrame: Weekly (week 0 till week 24)
Secondary outcomes:
measure: Change in serum sodium
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in serum magnesium
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in serum chloride
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in serum bicarbonate
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in serum calcium
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in serum creatinine
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in serum aldosterone
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in serum renin
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in fractional urinary excretion of potassium
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in fractional urinary excretion of sodium
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in fractional urinary excretion of chloride
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in fractional urinary excretion of magnesium
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in urinary calcium/creatinine ratio
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in urinary excretion of renin
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Change in urinary excretion of aldosterone
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Gitelman symptom questionnaire
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Blood pressure (including orthostatic hypotension measurement)
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Weight
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
measure: Muscle strength
timeFrame: Baseline, week 4, week 8, week 12, week 16, week 20, week 24
Other outcomes:
Locations:
city: Naples
country: Italy
facility: University Hospital of University of Campania "L. Vanvitelli"
city: Nijmegen
country: Netherlands
facility: Radboudumc
state: Gelderland
city: Rotterdam
country: Netherlands
facility: Erasmus MC
state: Zuid-Holland
Study officials:
affiliation: Radboud University Medical Center
name: Tom Nijenhuis, MD PhD
role: PRINCIPAL_INVESTIGATOR
References: