The Hydration to Optimize Metabolism (H2O Metabolism) Pilot Study

Study Overview
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Brief Summary
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This study evaluates increased hydration (1.5 L of water daily during 6 weeks) on top of habitual water intake in the lowering of the vasopressin marker copeptin and in the lowering of plasma glucose concentration in adults with signs of low water intake at recruitment (elevated levels of copeptin, high urine osmolality, low urine volume).

Detailed Description
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High plasma concentration of vasopressin (i.e. antidiuretic hormone) is a novel and independent risk factor for type 2 diabetes, the metabolic syndrome, cardiovascular disease and premature death. The main physiological role of vasopressin is to maintain constant plasma osmolality. Previous studies in rats and a Mendelian randomization study in humans suggest causality between elevated vasopressin concentration and elevated plasma glucose concentration. As vasopressin can be suppressed by increasing water intake, the investigators hypothesize that water supplementation in individuals with high vasopressin can lower plasma glucose and prevent diabetes. The aim of this pilot study is to test if six weeks of water supplementation of 1.5 Liters of extra water per day in low-drinkers with high copeptin can significantly alter hydration markers in general and reduce plasma copeptin in particular. Furthermore, the investigators also aim at investigating whether this 6-week water intervention can significantly reduce fasting plasma glucose concentration.

Official Title
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The Hydration to Optimize Metabolism (H2O Metabolism) Pilot Study

Conditions
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Low Water Intake, High Vasopressin

Intervention / Treatment
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* Dietary Supplement: Water


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Provision of informed consent Age 20-75 years High plasma concentration of copeptin of >6.1 pmol/L in women and > 10.7 pmol/L in men 24-hour urine osmolality > 600 milliosmol (mosm) /kg water. Exclusion Criteria: 24-hour urine volume >1.5 L Pregnancy or breastfeeding Plasma sodium <135 mmol/L Use of diuretics, lithium or SSRI drugs Chronic kidney disease (estimated glomerular filtration rate < 30mL/min) Heart failure Inflammatory bowel disease Type 1 diabetes or type 2 diabetes treated with insulin Vulnerable subjects (subjects with legal guardian, with loss of personal liberty)

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Intervention Model: Single Group Assignment
Interventional Model Description: All participants of this pilot intervention study had the intervention of 1.5 Liters of increased daily water intake per day during 6 weeks.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Water intervention<br>The participants increase their habitual daily water intake with 1.5 Liters of tap water per day during 6 weeks. | Dietary Supplement: Water<br>* Increased daily water intake with 1.5 Liters of water per day on top of habitual water intake.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fasting plasma copeptin concentration (pmol/L) | Change of fasting plasma copeptin between baseline and after 6 weeks of increased water intake. | 6 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 24 hour urine osmolality (mosm/kg H2O) | Change of 24 hour urine osmolality between baseline and after 6 weeks of increased water intake. | 6 weeks | 
| 24 hour urine volume (L/24h) | Change of 24 hour urine volume between baseline and after 6 weeks of increased water intake. | 6 weeks | 
| Drinking water (L/day) | Change of intake of tap and bottled water between baseline and after 6 weeks of increased water intake. | 6 weeks | 
| Total water (L/day) | Change of total water intake between baseline and after 6 weeks of increased water intake. | 6 weeks | 
| Fasting plasma glucose concentration (mmol/L) | Change of Fasting plasma glucose concentration between baseline and after 6 weeks of increased water intake. | 6 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hydration, Water, Vasopressin, Copeptin, Glucose