Intermittent Exogenous Ketosis (IEK) at High Altitude
NCT06097754, Not applicable, Unknown, Jozef Stefan Institute
Trial 10
As registered on ClinicalTrials.gov, in the graph's capture of the registry.
| Field | Value | Source |
|---|---|---|
| Title | Intermittent Exogenous Ketosis (IEK) at High Altitude | ClinicalTrials.gov |
| NCT number | NCT06097754 | ClinicalTrials.gov |
| Status | Unknown | ClinicalTrials.gov |
| Phases | Not applicable | ClinicalTrials.gov |
| Enrollment | 35 participants, actual | ClinicalTrials.gov |
| Lead sponsor | Jozef Stefan Institute | ClinicalTrials.gov |
| Conditions | Ketosis, Hypoxia | ClinicalTrials.gov |
| Interventions | Ketone ester, Placebo | ClinicalTrials.gov |
| First posted | 2023-10-24 | ClinicalTrials.gov |
| Last updated | 2023-10-24 | ClinicalTrials.gov |
Registered outcomes 19
Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.
| List | Outcome | Time frame | Description | Source |
|---|---|---|---|---|
| Primary | Cerebrovascular reactivity to carbon dioxide (CO2) | On Day 1 at sea level (in normoxia). On Day 2 (36 hours after) of exposure to hypobaric hypoxia. | Subjects will breathe 4 min 3% CO2 and 4 min 6% CO2 separated by 4 min of breathing ambient air. The middle cerebral artery will be continuously recorded by transcranial Doppler. | ClinicalTrials.gov |
| Primary | Cognitive function | On Day 1 at sea-level (in normoxia). On Day 0 and Day 2 (4 hours and 48 hours) after exposure to hypobaric hypoxia, respectively. | Cognitive function will be assessed by the computerized psychometric test battery: The Psychology Experiment Building Language (PEBL). The following cognitive tests will be used: The color-stroop test (measures attention, processing speed, and inhibitory control; the time it takes to complete the task and the accuracy of the responses; the number of correct and incorrect responses), the digit-span test (measures an individual's working memory capacity and short-term memory; the score of correctly remembered digit span), the ppvt test (measures the reaction time, attention, concentration; the time to react on the visual signal) the fitts test (measures the hand-eye coordination, fine motor skills, concentration; time to position the target) and the timewall test (measures the reasoning, calculating, reaction time, strategy and problem-solving; estimate the time when a moving target will reach a location behind a wall). | ClinicalTrials.gov |
| Primary | Acute Mountain Sickness (AMS) | Every day at 9.00 p.m. (before sleep) and at 6.15 a.m. (upon waking) in normoxia and hypobaric hypoxia, respectively. | Acute Mountain Sickness (AMS) will be assessed by the Lake Louise scale. The symptoms measured on the test include headache, gastrointestinal upset, fatigue/weakness, dizziness/light-headedness, and sleep disturbance. These are rated with an intensity level from 0 (the lowest) to 3 (the highest). A total score that is ≥3, including a headache, is indicative of AMS. | ClinicalTrials.gov |
| Primary | Change in lung function estimating forced vital capacity (FVC) and forced expiratory volume in 1st second (FEV1). | On Day 1 at sea level and on Day 3 of exposure to hypobaric hypoxia. | Lung function will be assessed by FVC and FEV1. | ClinicalTrials.gov |
| Primary | Change in lung function estimating peak expiratory flow (PEF). | On Day 1 at sea level and on Day 3 of exposure to hypobaric hypoxia. | Lung function will be assessed by PEF. | ClinicalTrials.gov |
| Primary | Change in lung function | On Day 1 at sea level and on Day 3 of exposure to hypobaric hypoxia. | Lung function will be assessed by the FEV1/FVC ratio. | ClinicalTrials.gov |
| Primary | Heart rate response to exercise | Every day during each 20-90 min long exercise bout performed between 9 a.m. and 6 p.m.. On Day 0 and Day 1 in normoxia. On Day 0, Day 1, Day 2, and Day 3 in hypobaric hypoxia. | Heart rate (HR, bpm) will be continuously monitored during different exercise bouts of a variety of intensities (moderate and heavy intensities will be used). | ClinicalTrials.gov |
| Primary | Respiratory response to exercise | Every day during each 20-90 min long exercise bout performed between 9 a.m. and 6 p.m.. On Day 0 and Day 1 in normoxia. On Day 0, Day 1, Day 2, and Day 3 in hypobaric hypoxia. | Oxygen consumption (VO2, L/min and mL/min/kg) will be continuously monitored during different exercise bouts of variety intensities (moderate and heavy intensities will be used). | ClinicalTrials.gov |
| Primary | Changes in muscular oxygenation during exercise | Every day during each 20-90 min long exercise bout performed between 9 a.m. and 6 p.m.. On Day 0 and Day 1 in normoxia. On Day 0, Day 1, Day 2, and Day 3 in hypobaric hypoxia. | Muscle oxygenation/deoxygenation will be continuously recorded during each exercise bout by Near Infra-Red Spectroscopy (NIRS) placed on the vastus lateralis. NIRS measure the quantity of oxygenated and deoxygenated haemoglobin and myoglobin (microM) in the investigated areas (vastus lateralis). | ClinicalTrials.gov |
| Primary | Changes in cerebral oxygenation during exercise | Every day during each 20-90 min long exercise bout performed between 9 a.m. and 6 p.m.. On Day 0 and Day 1 in normoxia. On Day 0, Day 1, Day 2, and Day 3 in hypobaric hypoxia. | Brain oxygenation/deoxygenation will be continuously recorded during each exercise bout by Near Infra-Red Spectroscopy (NIRS) placed at the frontal levels. NIRS measure the quantity of oxygenated and deoxygenated haemoglobin (microM) in the investigated areas (prefrontal cortex). | ClinicalTrials.gov |
| Primary | Changes in the rate of muscular oxygen consumption (mV#O2) | Every day before each 20-90 min long exercise bout performed between 9 a.m. and 6 p.m.. On Day 0 and Day 1 in normoxia. On Day 0, Day 1, Day 2, and Day 3 in hypobaric hypoxia. | Muscle oxygen consumption will be assessed using a previously validated protocol. Briefly, a Near Infra-Red Spectroscopy (NIRS) optode will be placed on the vastus lateralis muscle. Before the protocol, an ischemic calibration will be performed to normalize the NIRS signals by inflating the blood pressure cuff to 250-300 mmHg for a maximum of 5 min. Resting mV#O2 will be assessed from the decrease in muscle oxygenation which accompanies the arterial occlusion.Then, each subject will perform a 3 x 6 minutes moderate-intensity exercise, 8 minutes heavy-intensity exercise and graded exercise test. To measure the recovery of oxygen consumption after exercise, subject will have a series of arterial occlusion as follows: 5 occlusions 5sec on-5sec off, 5 occlusions 5sec on-5sec off, and 5 occlusions 10 sec on-20 sec off. | ClinicalTrials.gov |
| Primary | Duration of different sleep stages | Throughout the entire duration of the night, up to 8 hours after individual bedtime (between 10 p.m. and 6 a.m.). On Day 0 in normoxia. On Day 0 and Day 2 in hypobaric hypoxia. | Polysomnography will be used to assess the duration of the different sleep stages. | ClinicalTrials.gov |
| Primary | Changes in oxidative stress markers in the blood | Blood samples will be collected on Day 1 in normoxia and Day 1, Day 2 and Day 3 in hypobaric hypoxia at 6 a.m. (upon waking). | Oxidative stress markers concentration will be measured on collected venous blood sample. | ClinicalTrials.gov |
| Primary | Change in salivary cortisol concentration | Saliva samples will be collected on Day 1 in normoxia and Day 1, Day 2 and Day 3 in hypobaric hypoxia at 6 a.m. (upon waking). | Cortisol concentration will be measured on collected saliva samples. | ClinicalTrials.gov |
| Primary | Change in hydration status | Urine samples will be collected on Day 1 in normoxia and Day 1, Day 2 and Day 3 in hypobaric hypoxia at 6 a.m. (upon waking). | Urine samples will be assessed using urine specific gravity. | ClinicalTrials.gov |
| Primary | Baroreflex sensitivity | Within 24 h hours after exposure to normoxia and hypobaric hypoxia, respectively | At sea level: subjects will breath 6 min normal ambient air (21% O2, 0.03% CO2), 6 hypoxic normocapnic (13.8% O2, 0.03% CO2), and 6 min normoxic hypercapnic (21% O2, 3% CO2) air. At high altitude: subjects will breath 6 min hypobaric hypoxic (21% O2, 0.03% CO2), hypobaric normoxic (32% O2, 0.03% CO2), hypobaric normoxic hypercapnic (32% O2, 3% CO2) air. | ClinicalTrials.gov |
| Primary | Change in nocturnal oxygen saturation | Throughout the entire duration of the night, up to 8 hours after individual bedtime (between 10 p.m. and 6 a.m.). On Day 0 in normoxia. On Day 0 and Day 2 in hypobaric hypoxia. | Measured using pulse oximetry | ClinicalTrials.gov |
| Primary | Absolute amount of nocturnal urinary catecholamine excretion | From 10 p.m. to 6 a.m. on Day 0 in normoxia and Day 0, Day 1 and Day 2 in hypobaric hypoxia. | Measured using ELISA of collected nocturnal urine. Subjects empty bladder before sleep and urine will be collected throughout the entire duration of the night, up to 8 hours. Up to 8 hours from 10 p.m. to 6 a.m. on Day 0 in normoxia and Day 0, Day 1 and Day 2 in hypobaric hypoxia. | ClinicalTrials.gov |
| Secondary | Change in cerebral blood flow in the internal carotid artery | On Day 1 at sea level (in normoxia). On Day 2 (36 hours after) of exposure to hypobaric hypoxia. | Cerebral blood flow in the internal will be assessed every morning by doppler ultrasound. | ClinicalTrials.gov |
Outcomes 0
Each outcome the trial posted results for, in ClinicalTrials.gov's words.
| Type | Outcome | Time frame | Population | Units | Measured as | Source |
|---|
Results by group 0
Each measurement the trial posted, group by group, in the words and numbers it posted.
| Outcome | Group | Category | Value | Spread | Units | Source |
|---|
Participant flow 0
How many started, completed or left each group, period by period.
| Period | Milestone | Group | Participants | Units counted | Source |
|---|
Adverse events 0
Each adverse event the trial posted, group by group: the participants affected out of those at risk.
| Type | Event | Organ system | Group | Affected | At risk | Events | Source |
|---|
Adverse event totals 0
The totals the trial posted for each group.
| Total | Group | Affected | At risk | Source |
|---|
Papers 1
The papers the trial lists on ClinicalTrials.gov.
| PMID | Listed as | Source |
|---|---|---|
| 40523225 | DERIVED | PubMed |
Grants 0
The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.
| Project | Title | Principal investigators | Organization | Funder | Fiscal years | Source |
|---|
Trial comparisons 0
Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.
| Comparison | Source |
|---|
Tests 2
The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.
| Test | Named as | Source |
|---|---|---|
| Digit Span Test | Primary outcome | ConductCognition |
| Stroop Color-Word Test | Primary outcome | ConductCognition |
Source 5
| Field | Value | Source |
|---|---|---|
| Release | trials-2026-11-12-0.4.0 | ClinicalTrials.gov |
| Release manifest SHA-256 | 0f4a8d8c48aee2a7573ae0fa94ecbeab70c1adbe449bbc95c424bc7d3e97b9d4 | ClinicalTrials.gov |
| Registry capture | 2026-11-12 | ClinicalTrials.gov |
| Results copy, AACT | 2026-03-23 | ClinicalTrials.gov |
| NIH clinical studies file | 2026-11-13 | ClinicalTrials.gov |
Release trials-2026-11-12-0.4.0
ClinicalTrials.gov's posted results, through CTTI's AACT: ClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299 ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.
ClinicalTrials.gov: none stated ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.
NIH RePORTER's clinical studies and project files: Public domain (NIH RePORTER)