bluuebunny/crossref_metadata_2025 huggingface dataset:
065 Sleep and Gray Matter Volume: The Role of Physiological Arousal
Authors: Curtis Ashley , Nair Neetu , McGovney Kevin , Craggs Jason , McCrae Christina S
Published: May 2021

Introduction

Insomnia is associated with increased arousal. Brain regions involved in chronic insomnia are diffuse and the potential interactive role of physiological arousal in the association between insomnia symptoms and neural regions is unknown. This study examined whether physiological arousal (heart rate variability, HRV) moderated the association between sleep and gray matter (GM) volume of frontal [dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex (ACC)] and temporal [right/left (R/L) hippocampus] regions in adults with comorbid chronic widespread pain and insomnia (CWPI).

Methods

Forty-seven adults with CWPI (Mage=46.00, SD=13.88, 89% women) completed two weeks of diaries measuring sleep onset latency (SOL), wake time after sleep onset (WASO) and total sleep time (TST). Resting HRV was assessed via Holter monitoring (5 minutes). Root mean squared standard deviation of successive normal-to-normal heartbeats (RMSDNN) was computed. T1-weighted magnetic resonance images were obtained, segmented and co-registered to MNI space. GM volumes (DLPFC, ACC, R/L hippocampus) were estimated (FSL). Multiple regressions examined whether SOL, WASO or TST were independently associated with or interacted with RMSDNN in their associations with GM volumes, controlling for age.

Results

SOL interacted with RMSDNN in its association with ACC (B=-4.60, SE=2.06, p=.03, R-squared=.06). Longer SOL was associated with lower ACC volume at highest RMSDNN (lowest arousal; B=-103.54, SE=42.82, p=.02), not average/lowest RMSDNN (highest arousal, ps>.05). TST interacted with RMSDNN in its association with R hippocampus (B=-.22, SE=.10, p=.04, R-squared=.07). Shorter TST was associated with lower R hippocampal volume at lowest RMSDNN (highest arousal; B=7.39, SE=2.29, p=.002) and average RMSDNN (B=4.18, SE=1.50, p=.008), not highest RMSDNN (lowest arousal; p=.64). There was a trending association between WASO and R hippocampus volume (B=-13.67, SE=7.28, p=.07).

Conclusion

In patients with CWPI and highest physiological arousal, achieving longer TST may be important in terms of associations with right hippocampus volume. Improving (reducing) SOL may only impact ACC volume in those with lower physiological arousal. Trends of association between longer WASO and reduced right hippocampus volume warrant follow-up in larger samples. Findings highlight the interactive role of physiological arousal (HRV) in the neural mechanisms associated with sleep in CWPI.

Support (if any)

National Institute of Nursing Research (NR017168; Clinical trial: NCT02001077; PI: McCrae).
071 Actigraphy-Derived Sleep Metrics are Not Related to Central Hemodynamics or Arterial Stiffness in Healthy Adults
Authors: Culver Meral , Montoye Alexander , McMillan Nathan , Cross Brett , Riemann Bryan , Flatt Andrew , Grosicki Gregory
Published: May 2021

Introduction

Insufficient sleep is an emerging risk factor for cardiovascular disease. To evaluate the hypothesis that decrements in vascular function, due to poor sleep, may serve as a mechanistic link between sleep and cardiovascular disease, we explored relationships of actigraphy-derived sleep metrics with central hemodynamics and arterial stiffness in healthy young adults.

Methods

A total of 23 women and 27 men (23±5 yrs), free of known cardiovascular, metabolic, and renal disease, and not using sleep medication, participated in this study. ActiGraph GT9X wrist-worn accelerometers were used to measure sleep efficiency, total sleep time, wake after sleep onset, and number of awakenings over a seven-day period. Vascular health measures including central pressures and augmentation index at a heart rate of 75 beats per minute (AIx@75) were quantified via pulse wave analysis, and carotid femoral pulse wave velocity (cf-PWV) was assessed using applanation tonometry. Gender-specific z-scores for each of the sleep metrics were summed to assign each participant a “sleep score” (higher score = better sleep), and relationships between sleep scores and vascular health measures were explored using Pearson correlation coefficients.

Results

In men, sleep score (range: -4.92 to 9.10) was not related (P>0.05) to central systolic (114±15 mmHg, r=-0.26) or diastolic (72±7 mmHg, r=-0.21) pressures. Similarly, in women, sleep score (range: -5.02 to 5.34) was not related (P>0.05) to central systolic (103±11 mmHg, r=-0.09) or diastolic (72±10 mmHg, r=-0.21) pressures. Sleep score also failed to predict (P>0.05) indices of arterial stiffness, AIx@75 (men = 3.1±12.3, r=0.04; women = 5.2±9.5, r=-0.25) and cf-PWV (men = 6.2±0.8 m/s, r=-0.12; women = 5.7±0.5 m/s, r=-0.10).

Conclusion

In young healthy individuals, actigraphy-derived sleep characteristics were not related to central hemodynamics or non-invasive indices of arterial stiffness. Previously documented relationships between sleep and vascular function may be limited to less healthy populations, poorer sleepers, or only for certain sleep metrics.

Support (if any):
079 Sleep Quality Prediction During the Menstrual Cycle based on Daily Sleep Diary Reports
Authors: Sattari Negin , Mehrabadi Milad Asgari , Aqajari Seyed Amir Hossein , Zhang Jing , Simon Katharine , Alzueta Elisabet , Dulai Teji , de Zambotti Massimiliano , Baker Fiona , Rahmani Amir , Mednick Sara
Published: May 2021

Introduction

Estrogen and progesterone cycle through two main phases across a typical 28-day menstrual cycle: a perimense phase, when both hormones are low; and a non-perimenses phase, when both hormones are high. These fluctuations affect a range of daily activities, including sleep, mood, and physical feelings such as bloating. Here we aimed to predict differences in sleep quality during the perimenses and non-perimenses phases based on their daily reports.

Methods

We analyzed over 1200 nights of sleep diaries collected from 20 (18–35 yo) women across two months. We categorized days into perimenses when a night fell within 4 days prior to and 6 days after their self-reported first day of menses, and non-perimenses when a night fell 4 days before and 4 days after their reported positive ovulation. A random forest model was utilized in three different cases: 1) including the data associated with perimenses days 2) non-perimenses days and 3) considering the full data.

Results

Using the full data set we predicted subjects’ sleep quality with 70% accuracy. For the perimenses group our model predicted sleep quality with more than 80% accuracy while the prediction accuracy for non-perimenses was as high as 75%. Further, we observed that for perimenses women, overall alertness and alcohol consumption were among the most important features extracted from daily reports, while for the non-perimenses group, subjective happiness ratings and physical feelings of bloating were predicting sleep quality. Together our result showed that sleep quality reported on a daily basis can be predicted more accurately based on the phase of the menstrual cycle, where different daily features may play differential roles.

Conclusion

Sex hormones’ fluctuations across a month of menstrual cycle can affect a range of women’s daily functioning. We showed that the phase in menstrual cycle can influence women’s daily reports of their routines. Furthermore the fluctuations in these reports can be used to predict females’ sleep quality with higher accuracy compared to when the phase of menstrual cycle is not accounted for. Our results show the importance of considering the role of menstrual cycle when investigating sleep quality.

Support (if any):
091 The Feasibility of At-home Sleep Extension in Adolescents and Young adults: A Meta-Analysis and Systematic Review
Authors: Niu Xinran , Zhou Shijing , Casement Melynda
Published: May 2021

Introduction

Insufficient sleep duration has negative consequences for health and performance and is alarmingly common in adolescents and young adults. The primary aim of the meta-analysis and systematic review was to assess whether at-home sleep extension is a feasible means to improve sleep duration and daytime sleepiness without negative consequences for sleep quality or efficiency in adolescents and young adults. An additional aim of the review was to provide a qualitative summary of the health and performance outcomes associated with at-home sleep extension.

Methods

Peer-reviewed journal articles and doctoral dissertations available in English were searched and screened. Eligible studies had at least five consecutive days of at-home sleep extension, measurement of sleep duration during baseline/habitual sleep and extension of sleep opportunity, and participants 13–30 years of age. Information on primary sleep outcome (i.e., sleep duration), available secondary sleep outcomes (i.e., sleep opportunity, sleep efficiency, sleep quality, daytime sleepiness), and health and performance outcomes were extracted for quantitative synthesis and qualitative review.

Results

Of the 2254 articles assessed for eligibility, 17 studies (seven in adolescents and ten in young adults) met the eligibility criteria for this review. The average number of days of sleep manipulation was 14.29 (range: 5 to 49 nights). At-home extension of sleep opportunity reliably increased objective (ES = 0.97) and subjective sleep duration (ES = 2.19) and sleep quality (ES = 0.24), and decreased daytime sleepiness (ES = -0.39), when compared to unmanipulated sleep opportunity. Sleep extension was also found to have additional health (e.g., lower psychological stress) and performance benefits (e.g., better athletic performance) across ages and populations. A potential upward publication bias was found based on the distribution of within-subject effect sizes of actigraphic sleep duration.

Conclusion

The review indicates that at-home sleep extension is feasible in adolescents and young adults to improve sleep duration and daytime sleepiness, and maintain or improve sleep quality. However, the degree of improvement in sleep duration, sleep quality, and daytime sleepiness varied by study population and sleep extension method. Future research should investigate how variations in population and methods of sleep extension impact health and performance outcomes.

Support (if any):
112 Chronic sleep restriction disrupts slow-wave sleep homeostatic regulation and damages monoaminergic structures in the rat brain
Authors: Guzeev Mikhail , Kurmazov Nikita , Simonova Valentina , Belan Daria , Lapshina Ksenia , Pazi Maria , Ekimova Irina , Pastukhov Yuri
Published: May 2021

Introduction

The neurophysiological mechanisms underlying long-term neurological and cognitive disorders associated with chronic sleep restriction (CSR) are not fully understood. Here we evaluated how the sleep-wake cycle changes during and after a period of sleep restriction in rats, and whether CSR results in neurodegeneration in monoaminergic brain structures.

Methods

For CSR, 7-8-month-old Wistar rats underwent cycles of 3 h of sleep deprivation (SD) and 1 h of sleep opportunity (SO) continuously for 5 days on the orbital shaker. Telemetric sleep recordings were made before, during, and after CSR. Neurodegeneration in brain monoaminergic structures was assessed immunohistochemically.

Results

During SD, wakefulness comprised 85% of the total registration time; the remaining time was represented by drowsiness with low EEG delta power. Rapid eye movement sleep (REMS) was absent. During CSR, slow-wave sleep (SWS) and REMS were reduced by 62% and 57%. Total SWS time during SO periods increased on the first CSR day, but decreased to the baseline by the fifth CSR day. SWS EEG delta power (a measure of sleep intensity) decreased gradually from the first to the fifth CSR day. REMS total time remained elevated during all SO periods. During the first recovery day after CSR, SWS did not change, but REMS increased by 30%. No changes in total sleep time were found on the second recovery day but sleep intensity was decreased. In 14 days after CSR, all sleep parameters returned to the baseline. We revealed a loss of 24% of noradrenergic locus coeruleus neurons, 29% and 17% of dopaminergic neurons in the substantia nigra, the ventral tegmental area as well as in their striatal terminals.

Conclusion

We consider CSR as a damaging factor leading to a gradual suppression of homeostatic mechanisms governing sleep recovery. CSR can provoke neurodegeneration in monoaminergic structures involved in the regulation of emotional behavior, sleep, and autonomic functions.

Support (if any)

Ministry of Science and Higher Education of the Russian Federation grant (No. 075-15-2020-916 dated November 13, 2020) for the establishment and development of the Pavlovsky Center “Integrative Physiology for Medicine, High-Tech Healthcare and Stress Resilience Technologies”.
115 Age and Sex Differences in Behavioral Attention Across Baseline, Sleep Loss, and Recovery
Authors: Yamazaki Erika , Casale Courtney , Brieva Tess , Antler Caroline , Goel Namni
Published: May 2021

Introduction

There are established individual differences in performance resulting from sleep loss. However, differences in behavioral attention performance between demographic subgroups remain unclear, especially during recovery after sleep loss. Thus, we examined demographic subgroup performance differences during baseline, sleep loss (sleep restriction [SR] and total sleep deprivation [TSD]), and recovery (R).

Methods

Forty-one healthy adults participated in a 13-night experiment (2 baseline nights [10h-12h time-in-bed, TIB], 5 SR nights [4h TIB], 4 recovery nights [12h TIB], and 36h TSD). The 10-minute Psychomotor Vigilance Test (PVT), measuring behavioral attention, was administered every 2h during wakefulness. PVT lapses (reaction time [RT]>500ms) and 1/RT (response speed) were measured. PVT performance differences were investigated by sex (18 females) and by median split on age (range: 21-49y; median: 32y). Repeated measures ANOVAs on each study day examined PVT performance with demographic groups as the between-subject factor.

Results

SR1-2 and R1-2 showed significant between-subject effects by age: the older group had faster mean 1/RT than the younger group. SR2 showed a significant time*age group interaction: the older group had faster 1/RT from 0800h-1400h. B2, SR1, and R1 showed significant between-subject effects by sex: males had faster mean 1/RT than females. SR3 showed a significant time*sex interaction: males had faster 1/RT at 0800h and 1200h. PVT lapses (log transformed) analyses by age and by sex revealed significant between-subject effects at SR1 and R1. The direction of effects for lapses paralleled those for 1/RT: the younger group and females had more lapses than the older group and males, respectively. No other study days showed significant between-subjects or interaction effects.

Conclusion

For both age and sex, significant between-subject effects and/or interactions were revealed only in the beginning half of SR or recovery and not during TSD. These findings suggest that group differences exist when the effects of sleep loss are mild (i.e., SR1-3) or when the post-effects of sleep loss have diminished (i.e., R3-4); however, when the effects of sleep loss become more severe (i.e., SR4-5 or after a night of TSD), the well-established individual differences in response to sleep loss may overwhelm group differences.

Support (if any)

ONR Award No.N00014-11-1-0361;NIH UL1TR000003;NASA NNX14AN49G and 80NSSC20K0243;NIH R01DK117488
120 Seeking Treatment for Daytime Sleepiness: Beliefs and Attitudes Among People with Excessive Daytime Sleepiness
Authors: Kapoor Ashna , Wills Chloe , Tubbs Andrew , Grandner Michael
Published: May 2021

Introduction

Sleepiness impacts health and functioning, but many people with sleepiness do not seek care. Beliefs and attitudes about treatments for sleepiness may be useful to know in designing and targeting interventions.

Methods

N=28 participants with excessive daytime sleepiness (ESS>=10) but no other major medical problems were recruited from the community. They were administered an Epworth Sleepiness Scale and Fatigue Severity Scale at baseline, and asked about a wide range of beliefs/attitudes about seeking medical care about sleepiness, and whether they Strongly Agree (SA), Agree (A), Disagree (D), or Strongly Disagree (SD) with them. Ordinal logistic regressions examined agreement associated with baseline sleepiness and fatigue, adjusted for age, sex, and race/ethnicity. Nominal significance was determined as p<0.05.

Results

Rates of baseline agreement were as follows: People with insomnia (SA:50%,A:50%), sleep apnea (SA:68%,A:32%), and daytime sleepiness (SA:50%,A:36%,D:14%) “should discuss their problems with their doctor or health care provider.” “I have talked to my doctor about sleep problems” (SA:18%,A:23%,D:41%,SD18%). “I have talked to my doctor about daytime sleepiness (SA:23%,A:14%,D:45%,SD:18%). “If I had problems sleeping, I would discuss it with my doctor or health care provider” (SA:27%,A:50%,D:23%). “If I had problems with daytime sleepiness, I would discuss it with my doctor or health care provider” (SA:23%,A:50%,D:27%). “Excessive daytime sleepiness is something that can be improved with medical treatment” (SA:14%,A:55%,D:32%). “Excessive daytime sleepiness is something that can be improved with psychological treatment” (SA:9%,A:64%,D:27%). “Excessive daytime sleepiness is something that can be improved with complementary/alternative medicine treatment” (SA:9%,A:68%,D:18%,SD:5%). “I am concerned about side effects of medical treatments for daytime sleepiness” (SA:45%,A:42%,D:14%). These factors were not associated with baseline sleepiness. Those with higher baseline fatigue were more likely to report having talked to their doctor about sleepiness (oOR=1.33, p=0.02) and having talked to their doctor about sleep problems in general (oOR=1.54, p=0.02).

Conclusion

Real-world beliefs and attitudes about treatments for sleepiness reflect a general positive attitude towards addressing these issues with medical providers, not a very strong one. Side effects of medications are a common concern. Baseline fatigue may spur individuals to talk to their doctor.

Support (if any)

This work was supported by Jazz Pharmaceuticals
126 Exposure to simulated military operational stress decreases alertness in the morning but not the evening
Authors: LaGoy Alice , Beckner Meaghan , Sinnott Aaron , Conkright William , Eagle Shawn , Proessl Felix , Connaboy Christopher , Germain Anne , Flanagan Shawn , Martin Brian , Nindl Bradley , Ferrarelli Fabio
Published: May 2021

Introduction

Alertness, essential for optimal performance, may be modulated by acute stressors including: sleep loss, caloric restriction, cognitive load, and physical exertion. Prior sleep may attenuate sleep loss-related alertness decrements, thereby influencing performance and safety. We examined the effects of prior sleep and changes in alertness throughout the day and across days during a simulated military operational stress (SMOS) protocol.

Methods

As part of a 5-day SMOS protocol, fifty-eight active-duty or recently-separated military personnel (45 men; 26±6 years) completed subjective (Profile of Mood States, Vigor subscale) and objective (3-minute Psychomotor Vigilance Task; PVT) alertness assessments each morning (~0900) and evening (~2200). PVT outcomes included median reaction time (RT) and lapses. Day 2 (D2) reflected baseline testing, in which participants received an 8-hour sleep opportunity (2300-0700) and 100% of their estimated caloric need. Day 4 (D4) reflected peak stress, after two nights of participants receiving two 2-hour sleep opportunities (0100-0300, 0500-0700) and 50% of their estimated caloric need. Mixed effects ANOVAs were used to assess the effects of day (D2, D4) and time (Morning, Evening) on alertness. D2 and D4 reflected alertness at baseline and peak stress, respectively. Separate ANOVAs were performed to assess the effects of prior sleep: the Pittsburgh Sleep Quality Index (PSQI) assessed at intake, baseline polysomnography-measured sleep efficiency (SE), and baseline frontal slow wave activity (SWA; 0.5-4Hz). All analyses controlled for age.

Results

No significant interaction or main effects of day and time were found for Vigor or PVT lapses. Participants with higher PSQI scores reported lower Vigor (p=.01, η_p^2=.11). A significant interaction was found for PVT RT (p=.04, η_p^2=.07); morning RT was slower on D4 than D2, while evening RT did not differ across days. SE and SWA did not significantly influence alertness.

Conclusion

SMOS led to objective alertness deficits in the morning but not evening. Subjective alertness did not change during SMOS but was influenced by prior sleep quality (PSQI). Thus, both circadian and prior sleep-related factors influence performance during operational stress. Fatigue mitigation strategies delivered before and during military operations may support performance and safety.

Support (if any)

Department of Defense Award #W81XWH-17-2-0070
131 Sleep Quality as a Pathway from Stress to Cold Symptom Severity
Authors: Bansal Muskan , Ghose Sarah , Dautovich Natalie
Published: May 2021

Introduction

Stress is a known contributor to immune system suppression associated with higher illness susceptibility, including acute infectious respiratory illness, or the common cold. Sleep quality, shown to impact immunity, is an additional mechanism that may underlie the association between stress and cold symptomatology. Although the associations between stress and sleep and cold symptomatology have been examined separately, little is known about the mechanistic role of sleep in these associations. The present study examined sleep quality as a potential pathway between stress and cold symptomatology difference scores.

Methods

Archival data from the Common Cold Project (Pittsburgh Cold Study 3) were utilized for the present study. Participants were 213 adults (Mean Age=30.1 yrs., SD=10.9 yrs., 42.3% female) who completed a 5-day viral challenge and self-report measures of cold severity (Jackson Symptom Score; measured from beginning to end of viral challenge), baseline sleep quality (PSQI), and perceived stress as part of study participation. SPSS v 27 and Hayes’ PROCESS mediation macro were used to assess study aims. Age and sex were included as covariates.

Results

Greater perceived stress was significantly associated with worse sleep quality [B=.15, 95% CI .10, .21]. Sleep quality fully mediated the association between stress and changes in symptomatology; better sleep was associated with larger changes in cold severity [B=-.23, 95% CI -.43, -.04], defined as differences in symptomatology from beginning to end of the viral challenge, beyond stress alone. Zero-order correlation analyses revealed a trend level (r=.04, p=.06) association between sleep quality and aggregate cold severity, suggesting that as sleep improves, symptoms decrease.

Conclusion

Within the present sample, sleep quality surfaced as an indirect pathway linking stress to changes in cold severity. Better sleep was associated with greater changes in cold severity above perceived stress. These findings, together with the trend level, positive association between sleep quality and cold symptomatology, suggest that better sleep may be associated with less severe symptomatology. Future research should attend to mechanisms underlying the associations between stress, sleep, and cold symptomatology.

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149 Perceived sleep need, cumulative sleep deficit, and associations with daily affect in adolescents: 28 days over school & vacation
Authors: Shen Lin , Wiley Joshua , Bei Bei
Published: May 2021

Introduction

This study aimed to describe trajectories of daily perceived sleep need and sleep deficit across 28 consecutive days, and examine if cumulative sleep deficit predicts next-day affect.

Methods

Daily sleep and affect were measured over 2 weeks of school and 2 weeks of vacation in 205 adolescents (54.1% females, Mage = 16.9 years). Each day, participants completed actigraphy and self-reported the amount of sleep needed to function well the next day (i.e., perceived sleep need), sleep duration, and high- and low-arousal positive and negative affect. Cumulative actigraphy and diary sleep deficit were calculated as difference between perceived sleep need and sleep duration, weighted by sleep deficit over the past 3 days. Cross-lagged, multilevel models were used to test cumulative sleep deficit as a predictor of next-day affect. Lagged affect, day of the week, study day, and sociodemographics were controlled.

Results

Perceived sleep need was lower early in the school week, before increasing in the second half of the week. Adolescents accumulated sleep deficit across school days and reduced it during weekends. During weekends and vacations, adolescents’ self-reported, but not actigraphy sleep duration, met perceived sleep need. Higher cumulative actigraphy sleep deficit predicted higher next-day high arousal negative affect; higher cumulative diary sleep deficit predicted higher negative affect (regardless of arousal), and lower low arousal positive affect the following day.

Conclusion

Adolescents experienced sustained cumulative sleep deficit across school days, and whilst non-school nights appeared to be opportunities for reducing sleep deficit. Trajectories of sleep deficit during vacation suggested recovery from school-related sleep restriction. Cumulative sleep deficit was related to affect on a daily basis, highlighting the value of this measure for future research and interventions.

Support (if any):
162 Age, sex, and sleep continuity disturbance: Does binary sex impact sleep continuity while co-varying for age across the lifespan?
Authors: Boyle Julia , Muench Alexandria , Vargas Ivan , Bashian Hannah , Williams Natasha , Perlis Michael
Published: May 2021

Introduction

It is well-documented that insomnia symptoms can worsen with age and that women have a greater predisposition to insomnia symptoms than men. Additionally, it has been found that women are more likely to report insomnia symptoms across the lifespan (i.e., increased prevalence of insomnia regardless of age). The aim of the present study was to 1) confirm the finding that women are more likely to endorse having insomnia problems (specifically as they pertain to SL, WASO, and EMA) and 2) evaluate if there are binary sex differences with respect to sleep continuity disturbance (SCD) while accounting for age.

Methods

Sleep continuity (SL, WASO, EMA) duration (in minutes) and problem endorsement data was collected from individuals with insomnia complaints in an archival/community-based sample (n=1837;56.9% female; ages 18-87) (www.sleeplessinphilly.com). A multivariate analysis of covariance was conducted to determine a significant difference between sex (male, female) on SL, WASO, and EMA in minutes while controlling for age. Pearson correlations were run to determine relationships between age and SL, WASO, and EMA. Chi-Square tests were run to determine if there were sex differences in problem endorsement of SL, WASO, and EMA.

Results

Significant sex differences were observed in reports of SCDs as problematic, where more women endorsed SL (58.5%;p<.001), WASO (58.1%;p<.001), and EMA (56.9%;p<.001) as a problem than men. There were no significant effects of binary sex on sleep continuity disturbances when controlling for age. Age was significantly negatively related to SL(p<.001) and significantly positively related to WASO(p<.001) and EMA(p<.001).

Conclusion

These results confirm that women are more likely to report SCDs as a problem and that men and women experience similar levels of insomnia severity with respect to SL, WASO, and EMA. Clinically speaking, it may be important to evaluate insomnia with explicit questions about specific measures of SCD, followed by an inquiry regarding whether each SCD symptom “is a problem.” Future studies should consider gender identification as a relevant factor when evaluating for sleep continuity disturbances across the lifespan.

Support (if any):
164 Greater Light Exposure Is Associated with More Robust Rest-Activity Rhythms in Community-Dwelling Older Adults
Authors: Kim Minjee , Reid Kathryn , Maas Matthew , Vu Thanh-Huyen , Braun Rosemary , Daviglus Martha , Zee Phyllis
Published: May 2021

Introduction

Disrupted circadian rest-activity rhythms in older adults have been associated with an increased risk of cognitive decline and mortality. While light is one of the most potent synchronizing agents for the human circadian system, little is known about how light may influence rest-activity rhythms in older adults. We aimed to investigate the relationship between the amount of light exposure and rest-activity rhythm parameters using actigraphy data from a large cohort study.

Methods

553 community-dwelling older adults (aged 72±5, 142 (25.5%) female) from the Chicago Healthy Aging Study cohort underwent recording of activity and ambient light exposure for a minimum of five 24-hour periods, using Actiwatch-L (Phillips Respironics). The average recording duration was 6.7±0.5 days. An extension to the traditional cosine model was used to compute circadian rest-activity rhythm parameters, including the amplitude (a measure of strength), the goodness of fit (pseudo F statistic; a measure of robustness), and acrophase (timing of peak activity). Light exposure was measured by time spent above light thresholds of 100, 200, 500, and 1000 lux per day (TAT100, TAT200, TAT500, TAT1000, respectively). Bivariate associations between rhythm parameters and TAT values were examined with Spearman’s correlation coefficients. Variables that met a significant threshold (p<0.05) were entered into multivariable models to adjust for potential confounders including age, sex, race, and season.

Results

Robustness of the rest-activity rhythm, measured by extended cosine pseudo-F statistics, was associated with TAT100 (partial Spearman’s correlation coefficient 0.12, p=0.008), TAT200 (coefficient 0.13, p=0.03), TAT500 (coefficient 0.16, p<0.001), and TAT 1000 (coefficient 0.18, p<0.001). TAT100/200/500/1000 were also associated with the strength of the rest-activity rhythm, measured by amplitude of the extended cosine fit (partial Spearman’s correlation coefficient vs. TAT100: 0.12, p=0.006, TAT200: 0.14, p=0.002, TAT500: 0.16, p<0.001, TAT1000: 0.18, p<0.001), after adjusting for age, sex, race, and season.

Conclusion

Across the seasons, greater daily light exposure is associated with more robust circadian rest-activity rhythm in community-dwelling older adults. Whether the enhancement of light exposure can improve the strength and robustness of rest-activity rhythm needs to be tested with future intervention studies.

Support (if any):
165 Sex differences in the relationship between self-reported sleep quality and frailty in South Florida older adult outpatients
Authors: Kaur Sonya , McInerney Katalina , Slugh Mitchell , Bure Annelly , Sarno Marina , Getz Sarah , Levin Bonnie
Published: May 2021

Introduction

Frailty, a multidimensional construct of decreased reserve is an important predictor of functional independence and quality of life in older adults. There is a growing body of evidence highlighting reduced sleep efficiency and sleep duration predicts frailty in older adults. However, the sex differences in these relationships have been understudied.

Methods

253 participants (163) ranging in age from 50-92 years (mean= 67.59 years, S.D.= 9.22 years), underwent frailty assessment and completed the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS). Statistical moderation was assessed using nonparametric bootstrapping. All models statistically controlled for age, education and depression status.

Results

Higher scores on the PSQI predicted higher levels of fatigue (β=1.87, 95% CI= 0.48-3.27) and higher grip strength with the left hand (β= 0.81, 95% CI= 0.85-1.53). These relationships were significantly moderated by sex (β=-0.77, p=0.05 & β=-0.52, p=0.01). Specifically, high scores on the PSQI predicted more fatigue stronger grip strength in men (β=1.11, 95% CI=0.41-1.81) and weaker grip strength in women (β=-0.25, 95% CI=-0.51--0.02). There was no association between scores on the ESS and any of the frailty measures.

Conclusion

The relationships between PSQI scores and measures of fatigue and grip strength were statistically moderated by sex. These differences are not explained by sex differences in overall sleep quality or baseline frailty. This is consistent with the literature emphasizing sex differences in the effects of risk/lifestyle factors. It is possible that the relationship between sleep quality and frailty is altered by additional hormonal factors and warrant further investigation.

Support (if any)

This research was supported by the Evelyn F. McKnight Brain Research Foundation
170 Hispanic Ethnicity May Be Associated with Short Sleep Duration and Elevated Sleep Distress in U.S. Air Force Trainees
Authors: Burns Rosemary Estevez , Wang Xin Qun , Patience Marc , Ellis Jordan , Talcott Wayne , Hryshko-Mullen Ann , Star John Blue , Copeland Carol
Published: May 2021

Introduction

Sleep research among Hispanic populations is limited. Hispanics may be at higher risk of poor sleep when compared to other race/ethnicities. Non-white and other socioeconomically disadvantaged populations have higher rates of chronic health conditions. Epidemiological studies have substantiated the correlation between short sleep and a variety of negative health outcomes. Sleep is foundational to overall good health and functioning, impacting academic and physical performance in technical training, and crucial for an airmen’s adjustment to the rigor of a military career. Authors explored the role of race/ethnicity on perceived sleep health (e.g., sleep duration and sleep distress) among airmen attending technical school.

Methods

Sleep health survey was administered to two groups of Airmen at an Air Force technical training: In-processing: Airmen who just arrived to begin technical training, (n=187), Age: M= 20.83 (SD 3.26), 82.55% Male; upon completion of training, i.e., Out-processing: Airmen about to complete technical training, (n=302), Age M = 20.7 (SD 3.09), 85.81% Male. To account for correlations between Airmen from the same squadron, a covariates-adjusted generalized mixed-effects model was used. Associations between race/ethnicity and short sleep duration (≤6 hours), and between race/ethnicity and sleep pattern distress—among shorter sleepers as a sub-group—were examined. Racial/Ethnic frequency among short sleepers (n=135): 19.3 % Hispanic, 13.3% NH-Black, 55.6% NH-White, 6.6% NH-Multiracial, and 5.2% NH-Other.

Results

Among Hispanic Airmen, the out-processing group was 2.25 times as likely as the in-processing group to be short sleepers on weekdays (95% CI: 1.15 to 4.38, p=0.017). Among short sleepers in the out-processing group, Hispanic Airmen were significantly more worried/distressed about their sleep pattern than Black and White Airmen (OR=2.29, 95% CI: 1.18 to 4.42, p=0.014 and OR=2.29, 95% CI: 1.10 to 4.76, p=0.026, respectively).

Conclusion

Short sleep duration is a significant problem in the military and results suggest that race/ethnicity-related contextual factors may point to at risk subgroups. Others have considered the influence of perceived prejudice, access to social capital, cultural barriers to academic success, and potential sensitivity to somatic discomfort on sleep complaints. Future directions involve repeating this assessment with another cohort of technical training Airmen to see if findings replicate.

Support (if any)

none
185 Associations between Diet and Sleep Health in the UK Biobank Study
Authors: Hepsomali Piril , Groeger John
Published: May 2021

Introduction

It is well known that the prevalence of clinical and subclinical sleep issues is quite high, with a great economic and social burden on the society. As it is expected that the numbers of people suffering from clinical and subclinical sleep problems will increase in the coming years, new primary and/or complementary methods to improve and prevent poor sleep health across the population are urgently needed. In the current study, we aimed to conduct the largest investigation of diet and sleep health to date, through systematically examining the UK Biobank (UKB) data to find out whether diet quality and food groups play a role on sleep health.

Methods

This cross-sectional population-based study involved 502,494 participants. UKB food frequency and sleep questionnaires at baseline were used. Also, healthy diet, healthy sleep, and partial fibre intake scores were created. ANCOVA and regression models were used to examine the associations of healthy diet and dietary fibre intake scores with sleep health. Adjusted models included age, sex, BMI, and mental health symptomatology.

Results

We showed that both healthy diet and high partial fibre intake scores were associated with increased healthy sleep scores. Also, higher intakes of vegetables, fruits, fish, and unprocessed red meat were found to be associated with increased healthy sleep scores. On the other hand, processed meat intake was inversely associated with sleep health.

Conclusion

A healthy dietary pattern, and food groups (vegetables, fruits, fish, water) and nutrients (fibre) that are consumed as a part of a healthy dietary pattern were associated with better sleep health. Further work is needed to identify underlying mechanisms behind the impact of diet on sleep health.

Support (if any)

Acknowledgements: This research has been conducted using the UK Biobank Resource under Application Number ‘61818’. Funding: Funds received from Unilever UK Central Resources Limited to cover application fees.
191 Dream features of the Italian population across the first and second wave of the COVID-19 pandemic
Authors: Rescott Marisssa , Conte Francesca , De Rosa Oreste , Cellini Nicola , Malloggi Serena , Giganti Fiorenza , Ficca Gianluca
Published: May 2021

Introduction

The Italian government has responded to the second wave of the COVID-19 pandemic (autumn 2020) with a partial lockdown (PL). Here we aim to investigate the effects of the PL on dream features in the Italian population and to follow up on previous data collected during the total lockdown (TL) effected during the first wave of the pandemic (spring 2020).

Methods

Using a longitudinal approach, 214 participants (Mage=36.78±14.2y; 159F) who had participated in a previous survey (April 2020 – TL) completed the same online survey from November 10th to December 1st (PL). The questionnaires administered included the Pittsburgh Sleep Quality Index (PSQI) and a set of specific ad hoc questions on dream features (frequency, length, vividness, emotional tone, relation of content to the current health emergency) and their possible changes relative to the month preceding the lockdown, resulting in four time points (pre-TL, TL, pre-PL, PL).

Results

Frequency and length of dreams significantly increased from pre-PL to PL (both p’s<.01), while no difference emerged for vividness. As in TL, almost 30% of the subjects reported having COVID-19-related dreams during PL and, among these, 51% reported to face, in these dreams, problematic situations similar to those of their daily life. Both PSQI and dream negative emotionality scores significantly increased from pre-TL to TL, decreased in pre-PL and increased again in PL, indicating a parallel worsening of sleep quality and dream emotionality with both lockdowns. Dream negative emotionality in PL also showed positive correlations with PSQI scores and with negative mood, stress levels, general fear and fear about the COVID-19.

Conclusion

In line with the continuity hypothesis on the relationships between dreaming and the wake state, our data confirm that dream features are significantly and immediately affected by major life changes such as those brought about by the COVID-19 pandemic and related restrictions. Interestingly, dream emotionality and subjective sleep quality show a parallel profile across the different time points, suggesting the possible role of sleep quality as a modulating factor on dream affect.

Support (if any)

N/A
193 Sleep Variability and Affect Dynamics Among College Students during COVID-19 Pandemic
Authors: Mousavi Zahra , Lai Jocelyn , Yunusova Asal , Rivera Alexander , Hu Sirui , Labbaf Sina , Jafarlou Salar , Dutt Nikil , Jain Ramesh , Rahmani Amir , Borelli Jessica
Published: May 2021

Introduction

Sleep disturbance is a transdiagnostic risk factor that is so prevalent among emerging adults it is considered to be a public health epidemic. For emerging adults, who are already at greater risk for psychopathology, the COVID-19 pandemic has disrupted daily routines, potentially changing sleep patterns and heightening risk factors for the emergence of affective dysregulation, and consequently mood-related disturbances. This study aimed to determine whether variability in sleep patterns across a 3-month period was associated with next-day positive and negative affect, and affective dynamics, proximal affective predictors of depressive symptoms among young adults during the pandemic.

Methods

College student participants (N=20, 65% female, Mage=19.80, SDage=1.0) wore non-invasive wearable devices (the Oura ring https://ouraring.com/) continuously for a period of 3-months, measuring sleep onset latency, sleep efficiency, total sleep, and time spent in different stages of sleep (light, deep and rapid eye movement). Participants reported daily PA and NA using the Positive and Negative Affect Schedule on a 0-100 scale to report on their affective state.

Results

Multilevel models specifying a within-subject process of the relation between sleep and affect revealed that participants with higher sleep onset latency (b= -2.98, p<.01) and sleep duration on the prior day (b= -.35, p=.01) had lower PA the next day. Participants with longer light sleep duration had lower PA (b= -.28, p=.02), whereas participants with longer deep sleep duration had higher PA (b= .36, p=.02) the next day. On days with higher total sleep, participants experienced lower NA compared to their own average (b= -.01, p=.04). Follow-up exploratory bivariate correlations revealed significant associations between light sleep duration instability and higher instability in both PA and NA, whereas higher deep sleep duration was linked with lower instability in both PA and NA (all ps< .05). In the full-length paper these analyses will be probed using linear regressions controlling for relevant covariates (main effects of sleep, sex/age/ethnicity).

Conclusion

Sleep, an important transdiagnostic health outcome, may contribute to next-day PA and NA. Sleep patterns predict affect dynamics, which may be proximal predictors of mood disturbances. Affect dynamics may be one potential pathway through which sleep has implications for health disparities.

Support (if any):
194 Revealing the Sex Data Gap in Sleep and Chronobiology Research: A Systematic Review
Authors: Tir Selma , Spitschan Manuel
Published: May 2021

Introduction

Many aspects of sleep and circadian physiology appear to be sensitive to characteristics of the studied population, most notably sex. While recent research robustly highlights the importance of considering participant-level demographic information, it is not clear to what extent this information is available in the large body of already published literature. In this systematic review, we evaluated the study sample characteristics in the published sleep and chronobiology research over the past 40 years.

Methods

Articles published between 1979 and 2019 (odd years) in the top eight sleep and chronobiology journals, identified by their five-year Impact Factor, were found through MEDLINE. 6,777 articles were initially included for screening. Inclusion requirements included conducting original research, reporting human data, and recruiting volunteers. The reporting of sample size, age, sex, gender, ethnicity, level of education, socio-economic status, and profession of the study population was scored binarily (0 = not reported), and any reported aggregate summary statistics for these variables were recorded. Funding source, geographical location and clinical focus of the article were examined, as well as whether data were analyzed including any of the demographic variables as covariates.

Results

~75% of screened articles met inclusion criteria. While >90% of studies reported age or sex, all other variables were reported in <10% of cases. We found that sex balance greatly changed over the years, from a ~3:1 male to female ratio in the 1990s to a near-equal representation in the 2010s. Overall, ~75% of studies recruited both male and female participants. Of studies recruiting a single sex, ~50% all-female studies focused on a sex-dependent feature, compared to <5% in all-male studies.

Conclusion

In this comprehensive review, we found that the majority of studies report at least sex or age, while many other important variables are typically not reported. Reporting quality is highly variable, indicating an opportunity to standardize reporting guidelines for participant-level characteristics to facilitate disaggregated data analyses.

Support (if any)

Wellcome Trust (204686/Z/16/, 204686/Z/16/A); Linacre College, University of Oxford.
198 COVID-19 Pandemic Nightmares at the US-Mexico Border
Authors: Begay Tommy , Valencia Dora , Ghani Sadia , Delgadillo Marcos , Bastien Célyne , Madhivanan Purnima , Krupp Karl , Ruiz John , Killgore William D S , Wills Chloe , Grandner Michael
Published: May 2021

Introduction

The COVID-19 pandemic has impacted individuals in many ways, including anecdotal reports of nightmares. However, little data exists regarding the experience of COVID-related nightmares, especially among the distressed population at the US-Mexico Border. This is especially relevant given the clinical importance of nightmares as risk factors for poor mental health and sleep disturbances.

Methods

Participants were N=155 individuals who completed the Nogales Cardiometabolic Health and Sleep (NOCHES) and were contacted about completing a COVID sub-study (95% Hispanic/Latino). Participants were asked for the number of nightmares that they have experienced since the pandemic started. They were also asked whether they had nightmares about confinement, claustrophobia, suffocation, oppression, drowning, failure, helplessness, natural disasters, anxiety, evil forces, war, separation from loved ones, being chased, sickness, death, COVID, and apocalypse. They were also asked whether they experienced, due to the pandemic, increased general, financial, food, housing, familial, relationship, and media-related stress. Each of these items was coded from 0 (“Strongly Disagree”) to 3 (“Strongly Agree”), with total scores ranging from 0-21. Regression analyses (linear for frequency and binary logistic for content) examined stress score as independent variable, adjusted for age, sex, financial status, education, and mental health (PHQ4).

Results

Those who experienced greater pandemic-related stress reported more nightmares (age/sex-adjusted B=0.23, p<0.0005, fully-adjusted B=0.23, p<0.0005). They were also more likely to have nightmares about confinement (adjusted odds ratio [OR]=1.69, p=0.008), suffocation (OR=1.41, p=0.020), failure (OR=1.23, p=0.049), being chased (OR=1.24, p=0.013), sickness (OR=1.26, p=0.022), and COVID (OR=1.37, p=0.003).

Conclusion

Those who experienced more pandemic-related stress reported more nightmares, even after adjusting for depression/anxiety symptoms. In addition, those with more pandemic-related stress were more likely to have nightmares about COVID itself, as well as confinement and suffocation, being chased, failure, and sickness in general. Perhaps efforts to reduce pandemic-related stress will reduce these nightmare experiences, which may have beneficial effects on other areas of mental health.

Support (if any)

R01MD011600, R01DA051321