Cerebromicrovascular Effects of Time-Restricted Eating in Older Adults

Study Overview
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Brief Summary
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The central hypothesis of this study is that closer adherence to time restricted eating (TRE) will improve endothelial function, neurovascular (NVC) responses, resulting in improved cognitive performance, potentially through activation of SIRT1-dependent vasoprotective pathways.

Detailed Description
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This hypothesis will be tested by assessing the effect of TRE (not more than 10hr eating window each day for 6 months) in healthy adults (≥21 years of age). The group of subjects enrolled into TRE arm will be compared to control group. All participants will be randomized into either arm of the study.

Official Title
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Cerebromicrovascular Effects of Time-Restricted Eating in Older Adults

Conditions
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Time Restricted Eating

Intervention / Treatment
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* Other: Time restricted eating


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: -Healthy adults ≥21 years of age Exclusion Criteria: -Inability to read or write in English

Ages Eligible for Study
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Minimum Age: 21 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: Other
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>no intervention | |
| Experimental: Time restricted eating<br>not more than 10 hrs. eating window daily goal for 6 months | Other: Time restricted eating<br>* not more than 10 hrs. eating window daily goal for 6 months<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in neurovascular coupling using functional near infrared spectroscopy (fNIRS) | Functional near infrared spectroscopy (fNIRS) will be performed during the cognitive n-back task. fNIRS approach generates data that represent a relative change in oxygenated and deoxygenated hemoglobin measured over the cortical brain tissues. Neurovascular coupling will be evaluated as a change in oxy- and deoxy-hemoglobin between before and after treatment. | baseline, up to 6 months | 
| Change in neurovascular coupling using transcranial Doppler | Transcranial Doppler sonography will be used to measure the change in the blood flow velocities during the cognitive n-back task between before and after treatment. | baseline, up to 6 months | 
| Change in neurovascular coupling using the dynamic retinal vessel analysis | Flicker light-induced dilation of the retinal vessels (percentage increase over baseline diameter) will be measured in the right or left eye of each study participant using the Dynamic Vessel Analyzer (DVA, IMEDOS Systems, Jena, Germany). The change in retinal vessel diameters is tracked and reported as a %change from baseline, before and after treatment. . | baseline, up to 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in microvascular endothelial function | Changes in microvascular endothelial function will be assessed using laser speckle contrast imaging (LSCI) in the hand using the flow mediated dilation approach. The change in skin perfusion is calculated and reported as a %change from baseline, between before and after treatment. | baseline, up to 6 months | 
| Change in macrovascular endothelial function | Changes in macrovascular endothelial function will be assessed using sonography during flow mediated dilation approach. The change in brachial artery diameter is calculated and reported as a %change from baseline, between before and after treatment. | baseline, up to 6 months | 
| Change in deep tissue oxygen saturation | Transcutaneous deep tissue oxygen saturation will be measured using the inSpectra near infrared device. The data are calculated and reported as a %change from baseline, between before and after treatment. | baseline, up to 6 months | 
| Change in arterial stiffness | The arterial stiffness will be measured using the pulse wave analysis approach (SphygmoCor, Atcor medical, Itasca IL, or similar). Analysis generated the augmentation index which will be used for comparison before and after treatment. | baseline, up to 6 months | 
| Change in ECG | ECG will be recorded for heart rate variability analysis. The values of high frequency domain, low frequency domain, their ratio, as well as total power will be calculated and used for comparison before and after treatment. . | baseline, up to 6 months | 
| Change in Glycocalyx - perfused boundary region | Video recordings of the sublingual vasculature will be performed using the high definition video camera GlycoCheck (Microvascular health solutions). Data collected will include perfused boundary region (um), and will be used for comparison before and after treatment. | baseline, up to 6 months | 
| Change in capillary density | Video recordings of the sublingual vasculature will be performed using the high definition video camera GlycoCheck (Microvascular health solutions). Data collected will include capillary density (mm/mm^2), and will be used for comparison before and after treatment. | baseline, up to 6 months | 
| Change in red blood cell velocity | Video recordings of the sublingual vasculature will be performed using the high definition video camera GlycoCheck (Microvascular health solutions). Data collected will include red blood cell velocity (um/sec), and will be used for comparison before and after treatment. | baseline, up to 6 months | 
| Change in Attention | The allocation of one's limited capacities to deal with an abundance of environmental stimulation will be measured in a combined Flanker Inhibitory Control and Attention Test.Units of measure - score (from 0 to 10, bigger number is better). Reported as a %change from baseline, before and after treatment. | baseline, up to 6 months | 
| Change in Episodic Memory | Cognitive processes involved in the acquisition, storage and retrieval of new information, will be measured using the Picture Sequence Memory Test. Unit of measure - overall score (bigger number is better). Reported as a %change from baseline, before and after treatment. | baseline, up to 6 months | 
| Change in Working Memory | The ability to store information until the amount of information to be stored exceeds one's capacity to hold that information will be measured using the List Sorting Working Memory Test. Unit of measure - overall score (bigger number is better). Reported as a %change from baseline, before and after treatment. | baseline, up to 6 months | 
| Change in Language | Picture Vocabulary Test measures receptive vocabulary administered in a computer-adaptive test (CAT) format. Respondents select the picture that most closely matches the meaning of the word, before and after treatment. Unit of measure - overall score (bigger number is better). Reported as a %change from baseline, before and after treatment. | baseline, up to 6 months | 
| Change in Executive Function | The capacity to plan, organize and monitor the executive of behaviors that are strategically directed in a goal-oriented manner, will be measured using the Dimensional Change Card Sort Test. Units of measure - score (from 0 to 10, bigger number is better). Reported as a %change from baseline, before and after treatment. | baseline, up to 6 months | 
| Change in Processing Speed | Pattern Comparison Processing Speed Test assesses the amount of information that can be processed within a certain unit of time. Items are simple so as to purely measure processing speed. Units of measure - score (from 0 to 130, bigger number is better). Reported as a %change from baseline, before and after treatment. | baseline, up to 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Time restricted eating, Intermittent fasting, neurovascular coupling, cognitive function, aging