The Influence of Sleep on Cardiovascular Outcomes
NCT Number: NCT06535178
Acronym: DISCO
Status: RECRUITING
Study Type: INTERVENTIONAL
Phases: NA
Conditions: Circadian Rhythm|Cardiometabolic Health|Vascular Health
Interventions: BEHAVIORAL: Sleep Regularity Group
Sponsor: Oregon Health and Science University
Collaborators: Medical Research Foundation, Oregon
Sex: ALL
Age: ADULT
Enrollment: 30
Study Design: Allocation: NON_RANDOMIZED|Intervention Model: PARALLEL|Masking: SINGLE (PARTICIPANT)|Primary Purpose: OTHER
Start Date: 2024-07-01
Completion Date: 2025-09-30
Locations: Oregon Health & Science University, Portland, Oregon, 97239, United States

Summary:
The goal of this study is to identify the effects of sleep regularity on cardiovascular regulatory mechanisms. The investigators are hoping to discover if improving the regularity of sleep timing will improve metabolic and vascular health markers. The protocol is a 12-week prospective cohort study that includes both field and in-laboratory data collection in ostensibly healthy male and female adults, aged 18-40years.

Primary Outcome Measures: Changes in dim-light melatonin onset, Saliva samples will be collected pre- and post-12-week intervention and will be assayed for melatonin using standardized assays. Dim-light melatonin onset will be calculated using the linear interpolated point in time in which each participant's melatonin crosses and remains elevated above a 4pg/mL threshold. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in SRI, SRI will be calculated from 2-weeks actigraphy data prior to the first in-laboratory visit. Changes in SRI will be measured for 2-weeks during Weeks 1-2, Weeks 6-7, and Weeks 11-12 for the intervention group and during Weeks 11-12 for the control group. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in vascular endothelial function, Vascular endothelial function will be assessed via flow mediated dilation pre- and post-12-week intervention. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in heart rate, Heart rate will be measured every \~30 minutes via a blood pressure cuff. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in blood pressure, Changes in resting blood pressure will be measured every \~30 minutes via ambulatory blood pressure machines for up to 48-hours during Weeks 1-2, Weeks 6-7, and Weeks 11-12 for the intervention group and Weeks 11-12 for the control group. Blood pressure patterns during the day and night will be assessed, as well as a contrast of day and nighttime blood pressure levels. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in resting cardiac vagal tone, High frequency power of the heart rate variability power spectrum will be used to estimate cardiac parasympathetic activity (vagal tone). These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in heart rate response to exercise, Beat by beat heart rate will be recorded during a Monark bicycle ergometer exercise test where workload will be increased every 3-min until \~75% age predicted heart rate max is achieved. Heart rate will be averaged at rest, during each 3-min stage, and each minute during a 2-minute recovery. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in blood pressure response to exercise, Beat by beat blood pressure will be recorded during a Monark bicycle ergometer exercise test. Blood pressure will be averaged at rest, during each 3-min stage, and each minute during a 2-minute recovery. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in energy metabolism, Resting energy expenditure and macronutrient oxidation will be measured via indirect calorimetry. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in glucose, Changes in glucose will be measures during Weeks 1-2, Weeks 6-7, and Weeks 11-12 for the intervention group and Weeks 11-12 for the control group. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12
Secondary Outcome Measures: Changes in MDA, Changes in malondialdehyde \[MDA\] will be measured pre- and post-12-week intervention. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in TAC, Changes in total antioxidant capacity \[TAC\] will be measured pre- and post-12-week intervention. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in CRP, Changes in C-reactive protein \[CRP\] will be measured pre- and post-12-week intervention. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in triglycerides, Changes in triglycerides will be measured pre- and post-12-week intervention. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in percent body fat, Percent body fat will be assessed via dual x-ray absorptiometry \[DEXA\] and a Tanita body composition scale in all participants at baseline. Changes in percent body fat will be assessed via DEXA (Intervention Group) and Tanita body composition scale (Control Group) post-12-weeks. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in weight, Weight will be assessed via dual x-ray absorptiometry \[DEXA\] and a Tanita body composition scale in all participants at baseline. Changes in weight will be assessed via DEXA (Intervention Group) and Tanita body composition scale (Control Group) post-12-weeks. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in BMI, Body mass index \[BMI\] will be assessed via dual x-ray absorptiometry \[DEXA\] and a Tanita body composition scale in all participants at baseline. Changes in BMI will be assessed via DEXA (Intervention Group) and Tanita body composition scale (Control Group) post-12-weeks. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12|Changes in PIPR, Changes in post illumination pupil response \[PIPR\] will be measured using a near-infrared illumination and solid-state video pre-and post-12-week intervention. These data will be used to calculate mean differences and standard deviations between the control and intervention group for future experiments. Examined using planned comparison dependent t-tests to compare the changes pre- and post-12-weeks., Week 0 and Week 12