The Impact of Overnight Active Temperature Regulation on Gut Microbiome, Inflammation, and Circadian Rhythm.

Gut Microbiome Composition

alpha diversity: Shannon Index, beta diversity: Bray-Curtis, F/B ratio, genus-level abundance, SCFA concentrations

Systemic Inflammation (blood panel)

hsCRP levels

Circadian Rhythm of Core Body Temperature

Circadian core body temperature (ingested core temperature capsule). Cosinor analysis will be performed with the data collected. The capsule will stay in the participant's system until naturally excreted (1-5 days). The data recorded will be output as a temperature value (in Celsius, °C) and at a sampling rate of one temperature reading per minute.

Circadian Rhythm of Blood Pressure Rhythms

Blood Pressure (BP) Rhythms (systolic, diastolic, mean arterial pressure; MAP), including both single-point measurements and 24-hour ambulatory (mobile) measurements. The single-point BP readings will be manually enacted by the participant pressing the button on the monitor. During the 24-hour ambulatory monitoring, a BP reading will be taken every 30 minutes during the daytime and every 60 minutes once asleep, as per their reported normal bedtime. All BP readings are recorded and reported in millimeters of mercury (mmHg). The 24-hour BP readings will begin automatically 60 minutes before the participant's normal bedtime. Participants will continue wearing the BP cuff and monitor (attached to each other) for readings through the following night at that same time (therefore, it is a 24 hour reading). The protocol is marked in "Nights", however the metrics recorded in the day (AM) follow the same numerical convention (e.g. Day 11 = Night 11, where Night 11 is the nighttime of Day 11).

Objective Sleep Metrics: sleep staging, wakefulness after sleep onset and sleep onset latency (minutes)

Objective sleep metrics from sleep tracking devices (biometric tracking smart ring and Eight Sleep Pod) recorded in minutes. This includes sleep staging (N1: light sleep/N2: established light sleep/N3: deep sleep/REM: rapid eye movement) (minutes in each stage), wakefulness after sleep onset (WASO: tracks all periods of wakefulness following sleep onset, excluding the time it takes to fall asleep initially)(minutes), and sleep onset latency (the number of minutes it takes to transition from full wakefulness to the first stage of sleep).

Objective sleep metrics: Sleep efficiency (overall %)

Objective sleep metrics: Sleep efficiency (overall %) from sleep tracking devices (biometric tracking smart ring and Eight Sleep Pod). Sleep efficiency is the time spent asleep out of the total time spent in bed.

Wellbeing will be assessed by the World Health Organization Well-Being Index (WHO-5).

The WHO-5 is a validated questionnaire that measures mental well-being over the two weeks prior to completion. The WHO-5 assessment consists of five questions, each of which are rated from 0 (at no time) to 5 (all of the time). The numbers reported from those five questions are added together to get a raw total score ranging from 0-25. The final score is derived by multiplying the raw score by 4 to get a percentage (%) score of 0 to 100. This assessment is interpreted as follows: a higher score suggests better well-being, a score of 50 or below suggests poorer well-being. Clinically, this assessment is used as a screening tool to gauge quality of life rather. It is not used to provide any formal diagnoses.

Quality of life, including physical, mental and social health, will be assessed with the Patient-Reported Outcomes Measurement Information System (PROMIS) survey, a standardized and validated assessment.

PROMIS measures pain, fatigue, depression, anxiety, sleep disturbances and physical functioning. Results of the assessment will use standardized T-scores where a score of 50 represents the average (mean) of the population, with a standard deviation of 10. Higher T-scores indicate greater levels of the concept being measured. For example, a higher score in negative domains, such as fatigue, indicates greater fatigue, while a higher score in positive domains, such as physical functioning, indicates better physical functioning. Scores are interpreted based on how far they are from the population average of 50. Whether a higher or lower score indicates a greater concern depends on what is being measured, and the domain being measured.

Menopausal symptom severity will be assessed for female participants with the Menopause Rating Scale (MRS),a validated questionnaire designed to assess the severity of menopausal symptoms.

The Menopause Rating Scale (MRS) consists of 11 items, each rated from 0 (no symptoms) to 4 (very severe symptoms). Item scores are summed to produce a total score ranging from 0 to 44. Higher scores indicate greater symptom severity. This assessment is interpreted as follows; 0-4 indicates no to mild symptoms, 5-8 indicates mild symptoms, 9-15 indicates moderate symptoms, and 16 or above indicates severe symptoms. A baseline MRS score will be collected during the Preparatory Period at the participants discretion, but required to be successfully submitted by the conclusion of the Preparatory Period (Night 0).

Fatigue will be assessed with the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue) scale,a validated questionnaire designed to assess fatigue and its impact on daily activities and function.

The FACIT scale consists of 13 items, each rated from 0 (not at all) to 4 (very much), reflecting the previous seven days. Item scores are summed, with reverse scoring applied to negatively worded items, to produce a total score ranging from 0 to 52. For example, a response of 4 on a negatively worded item would be scored as 0, while a response of 0 would be scored as 4. Higher scores indicate less fatigue. A baseline FACIT score will be collected during the Preparatory Period at the participants discretion, but required to be successfully submitted by the conclusion of the Preparatory Period (Night 0).