Clinical trial NCT06381934: Validation of New Diagnostic Indices to Simplify Hyponatremia Therapy Assessment in Patients on Thiazide Diuretics
Official title: Validation of Diagnostic Indices to Simplify Hyponatremia Therapy Assessment - A Randomized, Controlled, Parallel-group Clinical Trial in Hospitalized Patients on Thiazide Diuretics (THAT Study)
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Thiazide Associated Hyponatremia
Keywords: Hyponatremia
Strong Apparent Ion Difference
Potassium Levels in Urine
Lead sponsor: University Hospital, Basel, Switzerland
Sponsor class: OTHER
First posted: 2024-04-24
Enrollment: 136
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: This study is looking at two new parameters, aSID and ChU, to see if these can help physicians to distinguish between different causes of low sodium levels (hyponatremia) in Patients taking a medicament against high blood pressure (thiazide). Researchers also want to see if using these new parameters to decide on treatment works just as well, or better, than the current standard treatments.

Detailed description: Thiazide or thiazide-like diuretics associated hyponatremia (thiazide associated hyponatremia, TAH) has a high prevalence in hospitalized patients. Patients might present either with a hypovolemic hyponatremia due to volume loss as a diuretic effect of thiazide, or with a syndrome of inadequate antidiuresis (SIAD) like hyponatremia in need of fluid restriction. Canonical urine indices are not useful in differential diagnosis, being directly influenced by thiazide itself. Current guidelines suggest the use of a clinical volume status assessment, but this approach has a poor diagnostic performance, with less than 50% of patients being rightly diagnosed thru that. The investigators showed in a retrospective analysis the possible role of strong apparent ion difference (aSID) and of chloride and potassium levels in urine (ChU) in differential diagnosis of TAH. The goal of this study is to investigate prospectively whether implementation of aSID and, in case of inconclusive aSID, ChU, allows a correct differential diagnosis and treatment of TAH.

Eligibility criteria: Inclusion Criteria:

* Hospitalized patients presenting at University Hospital Basel
* aged 18 years or older
* able to give informed consent as documented by signature
* with serum sodium level \< 130 mmol/l and serum osmolality \< 300 mOsm/kg
* with treatment with thiazide or thiazide-like diuretic

Exclusion Criteria:

* symptomatic hyponatremia in need of 3% hypertonic solution or intensive care treatment
* inability or contraindications to undergo the trial (i.e., any acute severe cardiovascular event requiring an immediate intervention)
* decompensated liver cirrhosis CHILD C
* decompensated heart failure NYHA III or higher
* severe valve impairment
* untreated adrenal insufficiency
* severe kidney disease in need of dialysis
* pregnancy or breastfeeding
* end of life care
* inability to follow the study procedures (i.e., language problem, dementia or critical illness).

Primary outcomes:
measure: Serum Sodium Level
timeFrame: at baseline, 24 hours and up to 72 hours
Secondary outcomes:
measure: Descriptive analyses: Changes in aSID in relation to changes in serum sodium levels
timeFrame: at baseline, 24 hours and up to 72 hours
measure: Descriptive analyses: Changes in ChU in relation to changes in serum sodium levels
timeFrame: at baseline, 24 hours and up to 72 hours
measure: Diagnostic performance analyses of: aSID and ChU
timeFrame: at baseline, 24 hours and up to 72 hours
measure: Diagnostic performance analyses of: aSID measured in blood gas analysis
timeFrame: at baseline, 24 hours and up to 72 hours
measure: Diagnostic performance analyses of: clinical volume status assessment
timeFrame: at baseline, 24 hours and up to 72 hours
measure: Diagnostic performance analyses of: not-invasive instrumental volume status assessment
timeFrame: at baseline, 24 hours and up to 72 hours
measure: Diagnostic performance analyses of: other hormones such as aldosterone, renin, arginine-vasopressin
timeFrame: at baseline, 24 hours and up to 72 hours
Other outcomes:
Locations:
city: Basel
country: Switzerland
facility: University Hospital Basel
Study officials:
affiliation: University Hospital, Basel, Switzerland
name: Laura Potasso, Dr. med. sc.
role: PRINCIPAL_INVESTIGATOR
References: