Temperature Optimization for Sleep

(SIESTA Trial)

Overseen By Peyton Berning

Age: 65+

Sex: Any

Trial Phase: Academic

Sponsor: Hebrew SeniorLife

Disqualifiers: Sleep disorders, Dementia, Diabetes, Neurological diseases, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 2

24 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial requires participants to have stable medication, which means you should not need to stop taking your current medications if they are stable. However, if your medications are not stable, you may not be eligible to participate.

What data supports the effectiveness of the treatment Biologically Adaptive Control of Bedroom Temperature for optimizing sleep?

Research shows that controlling bedroom temperature can improve sleep quality by increasing slow-wave sleep (deep sleep) and REM sleep (a sleep stage important for memory and mood). Additionally, warming the skin can help people fall asleep faster, suggesting that temperature adjustments can positively influence sleep patterns. ^{1 2 3 4 5}

Is temperature optimization for sleep generally safe for humans?

Research suggests that manipulating skin temperature within a comfortable range is generally safe for humans, as studies have shown it can affect sleep onset and maintenance without significant adverse effects. ^{1 3 5 6 7}

How does the treatment Biologically Adaptive Control of Bedroom Temperature differ from other sleep treatments?

This treatment is unique because it focuses on optimizing bedroom temperature to improve sleep by using biologically adaptive control, which adjusts the environment based on the body's natural temperature changes. Unlike medications or other interventions, it leverages the body's thermoregulation to enhance sleep quality without altering core body temperature. ^{1 3 6 8 9}

What is the purpose of this trial?

Nearly 50% of older adults complain of poor habitual sleep, and in many cases the underlying reason remains undiagnosed or unknown. Meanwhile, observational data suggest that bedroom temperature significantly influences sleep quality in community-dwelling older adults, including those without financial constraints that limit the use of heating and cooling. These individuals often struggle to maintain an optimal bedroom temperature, either due to impaired motor function and cognitive abilities, and/or a lack of awareness about how temperature affects their sleep. Therefore, for a non-trivial portion of older adults, optimizing the bedroom temperature presents an exciting and untapped opportunity to improve sleep without substantial cost, burden, and side effects. The intervention, biologically adaptive control of bedroom temperature, uses wearable health trackers (e.g., a Garmin watch) and smart thermostats to automate and personalize bedroom temperature control, tailoring it to each person's unique physiology and context. Initially, individuals will be monitored in their home to determine each person's specific temperature range that promotes sleep quality, as measured by the wearable device. After the initial monitoring, the smart thermostat will maintain bedroom temperature within the optimal range for sleep for as long as the individual uses the intervention. The primary purpose of this project is to test the feasibility of biologically adaptive control of bedroom temperature as an intervention to improve sleep in older adults and gather preliminary data to facilitate sample size calculations for a definitive trial. 20 Older adults, aged 65 and above, will be enrolled and their bedrooms bedrooms will be equipped with smart thermostats. The first aim focuses on assessing the feasibility of the intervention. This includes evaluating participant recruitment and retention, the acceptability of temperature adjustments (tracked through the number of temperature overrides by participants), and the self-reported likelihood of future use. The second aim involves analyzing the mean and variance of sleep outcomes during observation and intervention phases (separately for each group), examining the degree to which they vary with temperature variations and behavioral adaptations.

Research Team

Amir Baniassadi

Principal Investigator

Hebrew SeniorLife

Eligibility Criteria

This trial is for older adults aged 65 and above who experience poor sleep quality. Participants should be able to use a wearable health tracker and have a smart thermostat installed in their bedroom. There's no mention of specific exclusion criteria, but typically those with severe medical conditions or cognitive impairments that would interfere with the study may not qualify.

Inclusion Criteria

My medication doses have not changed recently.

Ability to speak and read English

Willing to follow study protocols for the duration of the study

Exclusion Criteria

Stated plans to not live within current place of residence for the duration of the study

Lack of a thermostat-controlled heating and cooling system to adjust the bedroom temperature. The existing system must be compatible with the thermostat selected in this study (Ecobee)

Evidence of severe cognitive impairment defined as a Modified Telephone Interview of Cognitive Status (TICS-m) score < 25

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

1 visit (in-person)

Observation

Participants sleep at their self-selected temperatures to gather baseline data

2 weeks

Daily monitoring (remote)

Intervention

Temperature adjustments are made to determine optimal sleep conditions

4 weeks

Daily monitoring (remote)

Experiment

Participants are divided into control and experimental groups to test optimal temperature settings

2 weeks

Daily monitoring (remote)

Follow-up

Participants are monitored for safety and effectiveness after the intervention

2 weeks

1 visit (in-person)

Treatment Details

Interventions

• Biologically Adaptive Control of Bedroom Temperature

Trial Overview The study tests if controlling bedroom temperature using smart thermostats can improve sleep in older adults. It uses wearable trackers to find each person's ideal sleeping temperature, then adjusts their room accordingly to see if it helps them sleep better.

Participant Groups

Group I: Intervention Experimental Treatment 1 Intervention

After the initial monitoring, the bedroom temperature for the experimental group will be set to what is deemed optimal for their sleep. Participants will always have the option of overriding our prescribed temperature.

Group II: Control Experimental Treatment 1 Intervention

After the initial monitoring, the control group will control their own bedroom temperature.

Who Is Running the Clinical Trial?

Hebrew SeniorLife

Lead Sponsor

Trials

52

Recruited

273,000+

Findings from Research

A study involving eight healthy subjects showed that warming the skin can significantly reduce the time it takes to fall asleep, with a 26% decrease in sleep-onset latency when skin temperature was increased by just 0.78 degrees Celsius.

This research provides experimental evidence that skin temperature changes can directly influence sleep onset, suggesting that managing skin temperature could be a potential strategy for improving sleep quality.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cutaneous warming promotes sleep onset. Raymann, RJ., Swaab, DF., Van Someren, EJ.[2022]

The study explores the relationship between body temperature and sleep, suggesting that changes in temperature may directly influence brain areas responsible for initiating sleep, indicating a potential causative link rather than just a coincidence.

Emerging evidence supports a model where thermoregulatory changes provide signals to the brain that help regulate sleep and wakefulness, potentially creating a feedback loop that maintains consolidated sleep.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Thermoregulation as a sleep signalling system. Gilbert, SS., van den Heuvel, CJ., Ferguson, SA., et al.[2022]

In a study involving six male subjects, sleep was significantly disrupted at temperatures below thermoneutrality (29°C), with 21°C being the most disruptive, indicating that colder temperatures negatively impact sleep quality.

The research found that both cold and warm temperatures outside the thermoneutral range similarly affected sleep patterns, suggesting that disruptions in REM sleep are likely due to general sleep process disturbances rather than specific thermoregulatory issues.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effects of high and low ambient temperatures on human sleep stages. Haskell, EH., Palca, JW., Walker, JM., et al.[2019]

Controlling bed temperature at a steady 32°C improved the amount of slow-wave sleep (SWS) in subjects, indicating that a comfortable sleep environment can enhance sleep quality.

Dynamic temperature adjustments that cool the bed during REM sleep and heat it during SWS led to an increased share of REM sleep, suggesting that optimal temperature settings may vary between different sleep stages.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Basic Study for Optimal Control of In-Bed Temperature during Sleep. Okada, S., Suzuki, S., Fukui, T., et al.[2020]

Skin temperature plays a significant role in regulating sleep and alertness, as it provides the brain with crucial information about sleep-permissive and wake-promoting conditions.

The review highlights the neuroanatomical pathways and physiological mechanisms through which skin temperature influences sleep regulation, suggesting potential applications for enhancing sleep, especially in individuals with insomnia.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Sleep, vigilance, and thermosensitivity. Romeijn, N., Raymann, RJ., Møst, E., et al.[2021]

A slight increase of just 0.4 degrees Celsius in skin temperature during sleep significantly reduced wakefulness and enhanced deep sleep stages in both young and elderly participants, with particularly strong effects observed in the elderly.

This method of skin warming could effectively address common sleep issues in older adults, such as reduced slow wave sleep and early morning awakenings, suggesting a promising non-invasive approach to improve sleep quality.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Skin deep: enhanced sleep depth by cutaneous temperature manipulation. Raymann, RJ., Swaab, DF., Van Someren, EJ.[2019]

The developed temperature regulation system for small mammals can precisely control body temperature during neurophysiological experiments, reacting to temperature differences as small as 0.001 degrees Celsius without introducing recording artifacts.

This innovative system, which uses a flexible, insulated blanket, has potential clinical applications, suggesting it could be beneficial for maintaining stable body temperatures in medical settings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A system with some unique features for maintaining desired body temperature in anesthetized and/or immobilized animals. Shipley, MT., Graf, M.[2019]

Whole body heating in rats, achieved by raising ambient temperature to 33-35 degrees C, significantly increased deep non-rapid eye movement sleep (NREMS2) during the first two hours of recovery compared to baseline and sleep-matched controls, suggesting a potential method to enhance sleep quality.

The study also found that brain temperature (Tbr) was lower for several hours following heating, indicating a possible link between body temperature regulation and sleep patterns, although rapid eye movement sleep did not show significant changes compared to controls.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Selective increases in non-rapid eye movement sleep following whole body heating in rats. Morairty, SR., Szymusiak, R., Thomson, D., et al.[2019]

A new mathematical model shows that ambient temperature significantly affects sleep quality by altering the normal progression of sleep stages, particularly during REM sleep.

The model incorporates thermoregulatory functions, providing insights into how humans adjust their sleep patterns in response to temperatures outside the comfortable range, highlighting the importance of temperature in sleep regulation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Modeling the long term effects of thermoregulation on human sleep. Bañuelos, S., Best, J., Huguet, G., et al.[2021]

References

1. United States pubmed.ncbi.nlm.nih.gov

Cutaneous warming promotes sleep onset. [2022]

2. England pubmed.ncbi.nlm.nih.gov

Thermoregulation as a sleep signalling system. [2022]

3. Ireland pubmed.ncbi.nlm.nih.gov

The effects of high and low ambient temperatures on human sleep stages. [2019]

4. United States pubmed.ncbi.nlm.nih.gov

Basic Study for Optimal Control of In-Bed Temperature during Sleep. [2020]

5. Germany pubmed.ncbi.nlm.nih.gov

Sleep, vigilance, and thermosensitivity. [2021]

6. England pubmed.ncbi.nlm.nih.gov

Skin deep: enhanced sleep depth by cutaneous temperature manipulation. [2019]

7. United States pubmed.ncbi.nlm.nih.gov

A system with some unique features for maintaining desired body temperature in anesthetized and/or immobilized animals. [2019]

8. Netherlands pubmed.ncbi.nlm.nih.gov

Selective increases in non-rapid eye movement sleep following whole body heating in rats. [2019]

9. England pubmed.ncbi.nlm.nih.gov

Modeling the long term effects of thermoregulation on human sleep. [2021]