Abstract 037: History Of Weight Cycling Is Prospectively Associated With Shorter And Poorer Quality Sleep, And Higher Sleep Apnea Risk In Diverse Us Women: Results From The AHA Go Red For Women Strategically Focused Research Network

Circulation ◽  
2021 ◽  
Vol 143 (Suppl_1) ◽  
Author(s):  
Vivian Cao ◽  
Nour Makarem ◽  
Moorea Maguire ◽  
Ivan Samayoa ◽  
Huaqing Xi ◽  
...  
Keyword(s):  
Sleep Quality ◽  
Sleep Onset ◽  
Research Network ◽  
Poor Sleep ◽  
Sleep Onset Latency ◽  
Weight Cycling ◽  
Onset Latency ◽  
Cross Sectional ◽  
History Of ◽  
Insomnia Severity

Introduction: Poor sleep and history of weight cycling (HWC) are associated with worse cardiovascular health, yet limited research has evaluated the association between HWC and poor sleep patterns. Hypothesis: We hypothesized that HWC would be associated with poor sleep in US women. Methods: The AHA Go Red for Women Strategically Focused Research Network cohort at Columbia University (n=506, mean age 37 ± 15.7y, 61% racial/ethnic minority) was used to evaluate cross-sectional associations of HWC and sleep characteristics at baseline, and prospective associations of HWC from baseline with sleep measures at 1-yr. HWC, defined as losing and gaining ≥ 10 lbs at least once (excluding pregnancy), and number of WC episodes were self-reported. Sleep duration, measures of sleep quality, insomnia severity, and obstructive sleep apnea (OSA) risk were assessed using the validated Pittsburgh Sleep Quality Index, Insomnia Severity Index, and Berlin questionnaire. Linear and logistic regression models, adjusted for age, race/ethnicity, education, health insurance status, pregnancy history, and menopausal status, were used to evaluate the relation of HWC with sleep. Results: Most women reported ≥1episode of weight cycling (72%). In linear models of cross-sectional and prospective data, each additional weight cycling episode was related to shorter sleep duration, poorer sleep quality, longer sleep onset latency, greater insomnia severity, more sleep disturbances and daytime dysfunction, lower sleep efficiency, and higher sleep medication use frequency. In logistic models, HWC (≥1 vs. 0 episodes) was associated with greater odds for short sleep, poor sleep quality, long sleep onset latency ≥26 min, high OSA risk, and sleep efficiency<85% ( Table ). Conclusion: HWC predicted poor sleep among women, suggesting that weight maintenance may represent an important strategy to promote sleep health. Long-term studies are needed to disentangle the complex relations between weight fluctuations and sleep across the life course.

scholarly journals The Impact of Sleep Timing, Sleep Duration, and Sleep Quality on Depressive Symptoms and Suicidal Ideation amongst Japanese Freshmen: The EQUSITE Study

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Atin Supartini ◽  
Takanori Honda ◽  
Nadzirah A. Basri ◽  
Yuka Haeuchi ◽  
Sanmei Chen ◽  
...  
Keyword(s):  
Depressive Symptoms ◽  
Suicidal Ideation ◽  
Sleep Quality ◽  
Sleep Duration ◽  
Sleep Onset ◽  
Poor Sleep ◽  
Sleep Onset Latency ◽  
Onset Latency ◽  
Poor Sleep Quality ◽  
The Impact

Aim. The aim of this study was to identify the impact of bedtime, wake time, sleep duration, sleep-onset latency, and sleep quality on depressive symptoms and suicidal ideation amongst Japanese freshmen.Methods. This cross-sectional data was derived from the baseline survey of the Enhancement of Q-University Students Intelligence (EQUSITE) study conducted from May to June, 2010. A total of 2,631 participants were recruited and completed the following self-reported questionnaires: the Pittsburgh Sleep Quality Index (PSQI), the Center for Epidemiologic Studies Depression Scale (CES-D), and the original Health Support Questionnaires developed by the EQUSITE study research team.Results. Of 1,992 participants eligible for analysis, 25.5% (n=507) reported depressive symptoms (CES-D total score ≥ 16), and 5.8% (n=115) reported suicidal ideation. The present study showed that late bedtime (later than 01:30), sleep-onset latency (≥30 minutes), and poor sleep quality showed a marginally significant association with depressive symptoms. Poor sleep quality was seen to predict suicidal ideation even after adjusting for depressive symptoms.Conclusion. The current study has important implications for the role of bedtime in the prevention of depressive symptoms. Improving sleep quality may prevent the development of depressive symptoms and reduce the likelihood of suicidal ideation.

Abstract P322: The Association Between Parity and Sleep Duration: a Study From the AHA Go Red for Women Strategically Focused Research Network (SFRN)

Circulation ◽  
2017 ◽  
Vol 135 (suppl_1) ◽  
Author(s):  
Natalie A Bello ◽  
Janet Catov ◽  
Brooke Aggarwal
Keyword(s):  
Sleep Quality ◽  
Sleep Duration ◽  
Research Network ◽  
Poor Sleep ◽  
Cross Sectional ◽  
Nulliparous Women ◽  
Increased Risk ◽  
The Relationship ◽  
Primiparous Women ◽  
Insomnia Severity

Background: Prior research has shown a J shaped association between parity and increased risk of cardiovascular disease (CVD), and several confounding factors have been identified. Sleep is emerging as an important, potentially modifiable risk factor for CVD, however few data have examined the relationship between parity and sleep. Methods: We studied 50 women in the AHA Go Red for Women Strategically Focused Research Network who provided information on pregnancy history and sleep patterns [56% non-white (n=28), mean age = 41±18 y]. The Pittsburgh Sleep Quality Index was used to assess sleep duration and quality, and the Insomnia Severity Index was used to assess level of insomnia. Parity was assessed using a standardized questionnaire as any pregnancies lasting > 6 mo. We used linear and logistic regression to examine the cross-sectional relation between sleep (duration, quality, and insomnia severity) and parity. Results: Prior pregnancy was reported in 32% (16 of 50) women and 36% (18 of 50) sleep ≤ 6 h/night. Parous women were significantly older (55 vs 34 y), more likely to have a BMI ≥25 kg/m 2 , HTN, and hyperlipidemia compared to nulliparous women. Sleep duration was significantly shorter in parous women (6 h vs 7 h), and the relationship remained significant for primiparous women (1 birth) after adjustment ( Figure ). More than half of parous women reported poor sleep quality (56%, 9 of 16) and insomnia (63%, 10 of 16) compared to 29% of nulliparous women (10 of 34) who reported each sleep disorder. After adjustment for age, there was no difference in sleep quality or insomnia between groups (p>0.05). Conclusion: In a diverse cohort of women, sleep duration was inversely related to parity. Primiparous women may be at heightened risk for the adverse cardiometabolic consequences of inadequate sleep duration, and may represent a teachable moment for CVD prevention. Ongoing studies to examine the relationship between sleep and pregnancy may provide important information on the pathways through which these risk factors modify future CVD.

Actigraphy assessment of sleep quality among patients with acute myeloid leukaemia during induction chemotherapy

2018 ◽  
Vol 8 (3) ◽  
pp. 274-277 ◽  
Author(s):  
Chi-Fu Jeffrey Yang ◽  
Kelli Aibel ◽  
Ryan Meyerhoff ◽  
Frances Wang ◽  
David Harpole ◽  
...  
Keyword(s):  
Acute Myeloid Leukaemia ◽  
Sleep Quality ◽  
Myeloid Leukaemia ◽  
Induction Chemotherapy ◽  
Sleep Onset ◽  
Sleep Efficiency ◽  
Poor Sleep ◽  
Sleep Onset Latency ◽  
Onset Latency ◽  
Acute Myeloid

ObjectivesPatients receiving induction chemotherapy for acute myeloid leukaemia (AML) anecdotally describe poor sleep, but sleep disturbances have not been well-characterised in this population. We aimed to test the feasibility of measuring sleep quality in AML inpatients using a wearable actigraphy device.MethodsUsing the Actigraph GT3X ‘watch’, we assessed the total sleep time, sleep onset latency, wake after sleep onset, number of awakenings after sleep onset and sleep efficiency for inpatients with AML receiving induction chemotherapy. We assessed patient self-reported sleep quality using the Pittsburgh Sleep Quality Index (PSQI).ResultsOf the 12 patients enrolled, 11 completed all actigraphy and PSQI assessments, demonstrating feasibility. Patients wore the Actigraph device for a mean (SD) of 15.92 (8.3) days, and actigraphy measures suggested poor sleep. Patients had a median average awakening length of 6.92 min, a median number of awakenings after sleep onset of 4 and a median sleep onset latency of 10.8 min. Actual median sleep efficiency (0.91) was high, suggesting that patients’ poor sleep was not due to insomnia but perhaps due to interruptions, such as administration of medications, lab draws and vital sign measurements.ConclusionsCollection of sleep quality data among inpatients with AML via a wearable actigraphy device is feasible. AML inpatients appear to have poor sleep quality and quantity, suggesting that sleep issues represent an area of unmet supportive care needs in AML. Further research in this areas is needed to inform the development of interventions to improve sleep duration and quality in hospitalised patients with AML.

scholarly journals Mindfulness-based therapy for insomnia for older adults with sleep difficulties: a randomized clinical trial

2021 ◽  
pp. 1-11
Author(s):  
Francesca Perini ◽  
Kian Foong Wong ◽  
Jia Lin ◽  
Zuriel Hassirim ◽  
Ju Lynn Ong ◽  
...  
Keyword(s):  
Older Adults ◽  
Sleep Quality ◽  
Behavioral Therapy ◽  
Sleep Onset ◽  
Exercise Program ◽  
Severity Index ◽  
Poor Sleep ◽  
Sleep Onset Latency ◽  
Post Intervention ◽  
Insomnia Severity

Abstract Objective Poor sleep is a modifiable risk factor for multiple disorders. Frontline treatments (e.g. cognitive-behavioral therapy for insomnia) have limitations, prompting a search for alternative approaches. Here, we compare manualized Mindfulness-Based Therapy for Insomnia (MBTI) with a Sleep Hygiene, Education, and Exercise Program (SHEEP) in improving subjective and objective sleep outcomes in older adults. Methods We conducted a single-site, parallel-arm trial, with blinded assessments collected at baseline, post-intervention and 6-months follow-up. We randomized 127 participants aged 50–80, with a Pittsburgh Sleep Quality Index (PSQI) score ⩾5, to either MBTI (n = 65) or SHEEP (n = 62), both 2 hr weekly group sessions lasting 8 weeks. Primary outcomes included PSQI and Insomnia Severity Index, and actigraphy- and polysomnography-measured sleep onset latency (SOL) and wake after sleep onset (WASO). Results Intention-to-treat analysis showed reductions in insomnia severity in both groups [MBTI: Cohen's effect size d = −1.27, 95% confidence interval (CI) −1.61 to −0.89; SHEEP: d = −0.69, 95% CI −0.96 to −0.43], with significantly greater improvement in MBTI. Sleep quality improved equivalently in both groups (MBTI: d = −1.19; SHEEP: d = −1.02). No significant interaction effects were observed in objective sleep measures. However, only MBTI had reduced WASOactigraphy (MBTI: d = −0.30; SHEEP: d = 0.02), SOLactigraphy (MBTI: d = −0.25; SHEEP: d = −0.09), and WASOPSG (MBTI: d = −0.26; SHEEP (d = −0.18). There was no change in SOLPSG. No participants withdrew because of adverse effects. Conclusions MBTI is effective at improving subjective and objective sleep quality in older adults, and could be a valid alternative for persons who have failed or do not have access to standard frontline therapies.

The effect of 4-h versus 6-h time restricted feeding on sleep quality, duration, insomnia severity and obstructive sleep apnea in adults with obesity

2021 ◽  
pp. 026010602110023
Author(s):  
Sofia Cienfuegos ◽  
Kelsey Gabel ◽  
Faiza Kalam ◽  
Mark Ezpeleta ◽  
Vicky Pavlou ◽  
...  
Keyword(s):  
Obstructive Sleep Apnea ◽  
Sleep Apnea ◽  
Sleep Quality ◽  
Sleep Onset ◽  
Control Group ◽  
Sleep Onset Latency ◽  
Restricted Feeding ◽  
Wake Time ◽  
Obstructive Sleep ◽  
Insomnia Severity

Background: Time restricted feeding (TRF) involves deliberately restricting the times during which energy is ingested. Preliminary findings suggest that 8–10-h TRF improves sleep. However, the effects of shorter TRF windows (4–6 h) on sleep, remain unknown. Aims: This study compared the effects of 4-h versus 6-h TRF on sleep quality, duration, insomnia severity and the risk of obstructive sleep apnea. Methods: Adults with obesity ( n = 49) were randomized into one of three groups: 4-h TRF (eating only between 3 and 7 p.m.), 6-h TRF (eating only between 1 and 7 p.m.), or a control group (no meal timing restrictions) for 8 weeks. Results: After 8 weeks, body weight decreased ( p < 0.001) similarly by 4-h TRF (–3.9 ± 0.4 kg) and 6-h TRF (–3.4 ± 0.4 kg), versus controls. Sleep quality, measured by the Pittsburgh Sleep Quality Index (PSQI), did not change by 4-h TRF (baseline: 5.9 ± 0.7; week 8: 4.8 ± 0.6) or 6-h TRF (baseline: 6.4 ± 0.8; week 8: 5.3 ± 0.9), versus controls. Wake time, bedtime, sleep duration and sleep onset latency also remained unchanged. Insomnia severity did not change by 4-h TRF (baseline: 4.4 ± 1.0; week 8: 4.7 ± 0.9) or 6-h TRF (baseline: 8.3 ± 1.2; week 8: 5.5 ± 1.1), versus controls. Percent of participants reporting obstructive sleep apnea symptoms did not change by 4-h TRF (baseline: 44%; week 8: 25%) or 6-h TRF (baseline: 47%; week 8: 20%), versus controls. Conclusion: These findings suggest that 4- and 6-h TRF have no effect on sleep quality, duration, insomnia severity, or the risk of obstructive sleep apnea.

778 Poor Sleep Quality is Associated with Reduced Myelination in Patients with Psychotic Disorders

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A303-A303
Author(s):  
Cagri Yuksel ◽  
Xi Chen ◽  
Lauren Watford ◽  
Margaret Gardner ◽  
Kathryn Lewandowski ◽  
...  
Keyword(s):  
White Matter ◽  
Sleep Quality ◽  
Psychotic Disorders ◽  
Sleep Onset ◽  
Sleep Loss ◽  
Magnetization Transfer Ratio ◽  
Poor Sleep ◽  
Sleep Onset Latency ◽  
Healthy Controls ◽  
Poor Sleep Quality

Abstract Introduction Recent studies show that sleep favors oligodendrocyte proliferation and myelination, and sleep loss is associated with alterations in white matter structure and decreased myelination. Psychotic disorders are characterized by disrupted white matter integrity, and abnormal axon and myelin structure. Despite common sleep disturbances in these disorders, little is known about the relationship between sleep quality and white matter findings. A novel in vivo neuroimaging technique that combines diffusion tensor spectroscopy (DTS) and magnetization transfer ratio (MTR) allows separately examining the axon structure and glial function, and myelin content, respectively. Using this method, we examined the association of sleep quality with white matter biology in a sample of patients with psychotic disorders and matched healthy controls. Methods Participants included patients diagnosed with bipolar disorder with psychotic features (euthymic or depressed, n=12) and schizophrenia spectrum disorders (n=9), and age and sex matched healthy controls (n=20). DTS and MTR data was collected from the right prefrontal white matter at 4T. DTS measures included apparent diffusion coefficients of water, NAA, creatine and choline. Sleep quality was measured using Pittsburgh Sleep Quality Index (PSQI). Results PSQI total score was significantly higher in patients. and patient sample included a higher percentage of poor sleepers (PSQI total score&gt;5). In patients, total PSQI score and sleep onset latency were significantly and negatively associated with MTR (F=6.9, p=0.02 and F=9.7, p=0.007, respectively). There was no difference in any DTS measures between groups. Conclusion Our preliminary results show that poor sleep quality is associated with decreased myelin content in the frontal lobe, in patients with psychotic disorders. This finding suggests that sleep loss may be a mediator of white matter alterations in psychosis. Support (if any) This work is supported by National Institute of Mental Health K23MH119322 to Cagri Yuksel

Abstract P199: Sleep Health Varies By Immigration Status And Acculturation Level In Women: Results From The American Heart Association Go Red For Women Strategically Focused Research Network

Circulation ◽  
2021 ◽  
Vol 143 (Suppl_1) ◽  
Author(s):  
Ivan A Samayoa ◽  
Nour Makarem ◽  
Vivian Cao ◽  
Moorea Maguire ◽  
Huaqing Xi ◽  
...  
Keyword(s):  
Sleep Duration ◽  
Sleep Problems ◽  
Immigrant Women ◽  
Sleep Onset ◽  
Research Network ◽  
Sleep Onset Latency ◽  
Onset Latency ◽  
Immigration Status ◽  
Sleep Health ◽  
The Us

Introduction: The Healthy Immigrant Effect refers to the phenomenon that recent immigrants are on average healthier than their native-born counterparts. Greater immigrant acculturation to the US has been linked to increased risk of cardiovascular disease (CVD), frequently attributed to factors including the adoption of Western diets and decreased physical activity. While immigrants may have healthier habits than US adults, which may confer protection from CVD, there is little research on sleep health, particularly in immigrant women. Hypothesis: We hypothesized that immigrants, particularly those with greater acculturation, would have more sleep problems. Methods: Baseline data from a 1-y, community-based cohort of 506 women (61% racial/ethnic minority, mean age=37±16y) was used to evaluate cross-sectional associations between acculturation and sleep. Women self-reported their immigration status and national origin. Acculturation was measured from responses to questions regarding language preference, nativity (sorted by regions: Asia, Caribbean, Latin America, other), length of residency in the US, and age at immigration. Sleep duration, sleep quality, risk of obstructive sleep apnea (OSA) and insomnia were assessed using validated questionnaires. Logistic regression models adjusted for age, health insurance, education and BMI were used to evaluate associations between acculturation measures and sleep characteristics. Results: Women who were immigrants (n=176) reported lower mean sleep duration (6.60 ± 1.25 vs. 6.85 ± 1.22 h, p=0.02) compared to non-immigrants (n=323); non-immigrants were more likely than immigrants to sleep ≥7h/night (OR: 1.50, CI: 1.01-2.22, p=0.04). Women who immigrated to the US before vs. after age 25 y had lower odds of having sleep onset latency ≥26 min (OR:0.97, CI:0.95-1.00, p=0.03). Immigrant women living in the US >10y vs. <10y had more than 2-fold higher odds of having longer sleep onset latency (≥26 min) (OR:2.43, CI:1.09-5.41, p=0.03). Immigrants from the Caribbean were more likely than immigrants from other regions to be at a high risk for OSA (OR:2.65, CI:1.07-6.55, p=0.04). Conclusions: Compared to non-immigrants, immigrant women exhibit shorter habitual sleep duration. Sleep problems may vary by age of immigration, years lived in the US, and region of origin, as those who immigrated when they were older and those who had lived in the US>10 y required more time to fall asleep and Caribbean immigrants had higher OSA risk.

scholarly journals 1134 Light Exposure At Daytime On Sleep Quality In Stroke Patient During Rehabilitation

SLEEP ◽  
2020 ◽  
Vol 43 (Supplement_1) ◽  
pp. A432-A432
Author(s):  
W Liao ◽  
S Lin ◽  
N Meng ◽  
H Tin ◽  
S Tsai ◽  
...  
Keyword(s):  
Sleep Quality ◽  
Stroke Patient ◽  
Light Exposure ◽  
Sleep Onset ◽  
Bright Light ◽  
Sleep Efficiency ◽  
Poor Sleep ◽  
Cross Sectional ◽  
Melatonin Concentration ◽  
Improve Sleep Quality

Abstract Introduction Lights maintain the day and night rhythm to set patients’ “wake-up cycle” and to stabilize their physiological functions, which may be expected to improve sleep. This study was aimed to investigate the relations between sleep quality and daytime light exposure in stroke patient during rehabilitation. Methods A cross-sectional study design was adopted and 120 stroke patients were recruited from rehabilitation wards of two medical centers and 116 patients completed this study. Research instruments including the Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Sleep Log, and Somnowatch (Germany) for actigaphy sleep and light were used to collect data and urinary melatonin concentration were measured. Results 47.4% of the patients had poor sleep quality (PSQI&gt;5), 74.1% had actigraphic sleep efficiency less than 85%, and 90.5% waked more than 30 minutes after sleep onset. The average exposure time at lower level light (≤149 lux) were 288.8 minutes, accounting for 48% of the day (8:00-18:00). Compared to lower light exposure group (less than 319.5 min at &gt;150 lux), those who exposed to higher level light (more than 319.5 min at &gt;150 lux) had increased 52.1 minutes in actigraphic total sleep time (TST, t=-2.134, p=0.035), increased 8% in actigraphic sleep efficiency (SE, t=-2.053, p=0.042), and decreased 41.1 minutes in actigraphic wake-after-sleep-onset (WASO, t=2.209, p=0.029). Urinary melatonin concentration increased 52.7 pg/ml, but not statistically significant (t=-1.277, p=0.205). Result of multiple regression analysis showed that after controlling for age, gender, post-stroke complications, and environmental interference, time of bright light exposure significantly affected subjective sleep satisfaction (p=0.014), TST (p=0.04), SE (p=0.041), and WASO (p=0.026). Conclusion Increasing time of bright illumination (≥150 lux) during daytime may improve sleep quality. Results of this study provide empirical references for non-drug intervention to improve sleep quality in patients with stroke. Support This study was supported by the Ministry of Science and Technology, MOST 105-2628-B-040 -005 -MY2.

Utility of Activity Monitors and Thermometry in Assessing Sleep Stages and Sleep Quality

2018 ◽  
Vol 1 (3) ◽  
pp. 108-121
Author(s):  
Natashia Swalve ◽  
Brianna Harfmann ◽  
John Mitrzyk ◽  
Alexander H. K. Montoye
Keyword(s):  
Sleep Quality ◽  
Skin Temperature ◽  
Sleep Stage ◽  
Sleep Onset ◽  
Sleep Efficiency ◽  
Sleep Stages ◽  
Sleep Onset Latency ◽  
Onset Latency ◽  
Activity Monitors ◽  
Research Grade

Activity monitors provide an inexpensive and convenient way to measure sleep, yet relatively few studies have been conducted to validate the use of these devices in examining measures of sleep quality or sleep stages and if other measures, such as thermometry, could inform their accuracy. The purpose of this study was to compare one research-grade and four consumer-grade activity monitors on measures of sleep quality (sleep efficiency, sleep onset latency, and wake after sleep onset) and sleep stages (awake, sleep, light, deep, REM) against an electroencephalography criterion. The use of a skin temperature device was also explored to ascertain whether skin temperature monitoring may provide additional data to increase the accuracy of sleep determination. Twenty adults stayed overnight in a sleep laboratory during which sleep was assessed using electroencephalography and compared to data concurrently collected by five activity monitors (research-grade: ActiGraph GT9X Link; consumer-grade: Fitbit Charge HR, Fitbit Flex, Jawbone UP4, Misfit Flash) and a skin temperature sensor (iButton). The majority of the consumer-grade devices overestimated total sleep time and sleep efficiency while underestimating sleep onset latency, wake after sleep onset, and number of awakenings during the night, with similar results being seen in the research-grade device. The Jawbone UP4 performed better than both the consumer- and research-grade devices, having high levels of agreement overall and in epoch-by-epoch sleep stage data. Changes in temperature were moderately correlated with sleep stages, suggesting that addition of skin temperature could increase the validity of activity monitors in sleep measurement.

scholarly journals Microclimate Thermal Management Using Thermoelectric Air-Cooling Duct System Operated at Five Incremental Powers and its Effect on Sleep Adaptation of the Occupants

Energies ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3695 ◽  
Author(s):  
Kashif Irshad ◽  
Salem Algarni ◽  
Mohammad Tauheed Ahmad ◽  
Sayed Ameenuddin Irfan ◽  
Khairul Habib ◽  
...  
Keyword(s):  
Sleep Quality ◽  
Cooling System ◽  
Sleep Onset ◽  
Air Cooling ◽  
Sleep Onset Latency ◽  
Onset Latency ◽  
Test Room ◽  
Environmentally Sustainable ◽  
Highly Sensitive ◽  
The Mean

In this study, the microclimate of the test room was regulated using thermoelectric air duct cooling system (TE-AD) operated at input powers-240 W, 360 W, 480 W, 600 W, 720 W, and 840 W, on subsequent nights. Fifteen (15) healthy male volunteers were recruited to sleep under these test conditions and their sleep quality was assessed by studying objective measures such as sleep onset latency (SOL), mean skin temperature and heart rate as well as subjective parameters like predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD). There was a consistent improvement on all studied parameters when the power of the system was increased from 240 W to 720 W. The mean sleep onset latency time was reduced from (M = 40.7 +/− 0.98 min) to (M = 18.33 +/− 1.18 min) when the operating power was increased from 240 W to 720 W, denoting an improvement in sleep quality. However, increasing the power further to 840 W resulted in deteriorating cooling performance of the TE-AD system leading to an increase in temperature of the test room and reduction in sleep comfort. Analysis of subjective indices of thermal comfort viz. PMV and PPD revealed that subjects are highly sensitive towards variations in microclimate achieved by changing the operating power of the TE-AD. This device was also found to be environmentally sustainable, with estimated reduction in CO2 emission calculated to be around 38% as compared to the conventional air-conditioning.

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