bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

Abstract

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&lt;.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

Abstract

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&lt;.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&lt; .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

Abstract

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 &gt;90% of studies reported age or sex, all other variables were reported in &lt;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 &lt;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

Abstract

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&lt;0.0005, fully-adjusted B=0.23, p&lt;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
224 Digital Media Use and Sleep in College Students during COVID-19 Pandemic
Authors: Li Winnie , Ye Lichuan 
Published: May 2021

Abstract

Introduction
To address the growing sleep deficiency epidemic in college students, more research is needed on recent factors that might affect sleep, such as the digital media use in this young adult population. Furthermore, sleep and the use of digital media can be heavily influenced by the COVID-19 pandemic. The purpose of this study is to examine the use of digital media during the pandemic, and its relationship with sleep disturbance, social isolation, physical and mental health in college students.

Methods
An online survey was sent out to college students enrolled in an urban university. Validated questionnaires including PROMIS (Sleep Disturbance, Global Mental Health, Global Physical Health, Social Isolation), Nighttime Media Usage, and Internet Addition Test were included in the survey. In addition, focus groups were conducted with a subsample of survey respondents to elicit a comprehensive understanding of how digital media use in daily life influences sleep during the COVID-19 pandemic. Data collection was conducted during June to December 2020.

Results
A total of 358 students completed the online survey. Sleep disturbance was significantly related to greater digital media use for recreational purposes two hours before bedtime (62.6±28.1 minutes, r=0.110, p=0.046), and a higher frequency of playing games (r=0.148, p=0.007) and using social media after going to bed (r=0.142, p=0.10). Sleep disturbance was significantly associated with social isolation (r=0.251, p&lt;0.001), poor global physical health (r=-0.186, p&lt;0.001) and mental health (r=-0.376, p&lt;0.001), and lower GPA (r=-0.167, p=0.004). Additionally, seven focus groups were conducted in a total of 32 students, suggesting that the increase in free time from the COVID-19 pandemic led to greater digital media use, compromising sleep duration and quality. With the increase of screen time also came feeling of guilt and anxiety which often led to greater awareness and self-control around media use.

Conclusion
Nighttime digital media use during the challenging pandemic time has a significant impact on poor sleep, which may lead to decreased academic performance, greater social isolation, and poor physical and mental health in college students. Effective interventions targeting digital media use are needed to improve sleep in this population.
Support (if any):
259 Tracking naturalistic sleep over the menstrual cycle with a wearable in healthy young women
Authors: Alzueta Elisabet , de Zambotti Massimiliano , Dulai Teji , Albinni Benedetta , Simon Katharine , Sattari Negin , Zhang Jing , Mednick Sara , Baker Fiona 
Published: May 2021

Abstract

Introduction
A woman’s menstrual cycle is characterized by hormonal changes that might affect sleep and therefore daily functionality. While some studies using self-reports have shown a lower sleep quality in the peri-menstruation phase, objective – in lab – studies have not found significant differences in sleep continuity during the menstrual cycle, but are limited by only a few recordings across the cycle. The aim of this study is to examine changes in sleep during the healthy menstrual cycle using a multi-sensory wearable, allowing continuous, objective, reliable and ecologically valid measurement.

Methods
12 healthy young women (28.14 ± 2.33) were monitored using Oura ring – a sleep and activity tracker – during an entire menstrual cycle. Participants also reported mood, readiness, and sleep quality using a diary. Four phases of the menstrual cycle were compared (menstruation, periovulation, mid-luteal, and late-luteal). Ovulation day was determined using a urinary luteinizing hormone test.

Results
Ovulatory cycles were confirmed by the Oura ring, which showed a significant increase in average nocturnal heart rate and skin temperature during the post-ovulatory luteal phase relative to menstruation and periovulation. Oura ring measures of sleep continuity (Sleep Onset Latency, Wake After Sleep Onset) and self-reported sleep quality did not change across the 4 menstrual phases. We observed a trend for objective sleep duration, which tended to be shorter in the mid-luteal and late-luteal phases. We also observed a small reduction in perceived readiness and mood during these two phases.

Conclusion
Physiological changes (increase in heart rate and body temperature) in the postovulatory phase of the menstrual cycle are detectable with the Oura ring. Sleep features remain quite stable during the healthy, ovulatory menstrual cycle, apart from a trend for slightly shorter sleep duration in the post-ovulatory phases. In comparison to self-reports, which rely on retrospective memory and might be biased by perception and mood, wearable technologies seem to be a sensitive and informative tool to track sleep and physiological changes during the menstrual cycle.

Support (if any)
Supported by RF1AG061355 (Baker/Mednick)
275 Evaluation of Multiple Wearable Sleep-Tracking Devices Tested Under Ad Lib Home Sleep Conditions
Authors: Chinoy Evan , Cuellar Joseph , Jameson Jason , Markwald Rachel 
Published: May 2021

Abstract

Introduction
Consumer wearable sleep-tracking devices are increasingly popular and have performed well versus gold standard sleep measurement techniques (polysomnography and actigraphy) in recent validation studies. However, most validation studies were conducted in laboratories under controlled conditions. We therefore aimed to test the validation performance of multiple consumer wearable sleep-tracking devices under real-world ad lib sleep conditions at home.

Methods
We tested 21 healthy young adults (12 women, 9 men; 29.0±5.0 years, mean±SD) for 7 nights each. Participants slept at home under ad lib sleep conditions, using a set of consumer wearable sleep-tracking devices and completed daily sleep diaries. Consumer wearables included the Fatigue Science Readiband, Fitbit Inspire HR, Oura Ring, and Polar Vantage V Titan. Participants also wore the Philips Respironics Actiwatch 2, a research-grade actigraphy watch, for comparison. To assess validity of sleep/wake measures, all devices were compared with the previously-validated Dreem 2 electroencephalography-based headband device. Analyses included agreement of epoch-by-epoch sensitivity (for sleep) and specificity (for wake), and sleep summary comparisons of time-in-bed (TIB) and total sleep time (TST).

Results
Sensitivity and specificity, respectively, were as follows: Actiwatch 2 (0.95, 0.36), Readiband (0.93, 0.43), Inspire HR (0.93, 0.45), Ring (0.94, 0.41), and Vantage V Titan (0.96, 0.33). Device average biases, in minutes±SD, for TIB and TST, respectively, were as follows: Actiwatch 2 (N/A, +0.7±42.4), Readiband (+18.2±34.9, +0.4±49.5), Inspire HR (+7.8±35.0, -5.9±44.4), Ring (+9.2±28.0, +4.4±44.5), and Vantage V Titan (+0.2±50.0, -3.2±46.1).

Conclusion
The consumer wearable devices had comparable sleep-tracking performance during real-world ad lib home sleep. Similar to prior studies, the devices all had high sensitivity and low-to-medium specificity, indicating a greater ability to accurately detect sleep than wake. Notably, specificity for most consumer wearables was higher than a research-grade actigraph, indicating potentially greater ability than actigraphy to detect wake. Sleep summary outcomes were similar among the wearables, which accurately tracked TIB and TST on most nights. However, on some nights there was still considerable bias and variability. Overall, preliminary findings indicate that consumer wearables are promising for tracking sleep and wake in real-world home conditions.

Support (if any)
Office of Naval Research, Code 34
293 Predictive utility of a brief scale to identify U.S. Army Soldiers who are genetically vulnerable and resilient to sleep loss
Authors: Mantua Janna , Mickelson Carolyn , Naylor Jacob , Ritland Bradley , Bessey Alexxa , Burke Tina , Sowden Walter , Mckeon Ashlee 
Published: May 2021

Abstract

Introduction
Sleep loss that is inherent to military operations can lead to cognitive errors and potential mission failure. Single Nucleotide Polymorphisms (SNPs) allele variations of several genes (COMT, ADORA2A, TNFa, CLOCK, DAT1) have been linked with inter-individual cognitive resilience to sleep loss through various mechanisms. U.S. Army Soldiers with resilience-related alleles may be better-suited to perform cognitively-arduous duties under conditions of sleep loss than those without these alleles. However, military-wide genetic screening is costly, arduous, and infeasible. This study tested whether a brief survey of subjective resilience to sleep loss (1) can demarcate soldiers with and without resilience-related alleles, and, if so, (2) can predict cognitive performance under conditions of sleep loss.

Methods
Six SNPs from the aforementioned genes were sequenced from 75 male U.S. Army special operations Soldiers (age 25.7±4.1). Psychomotor vigilance, response inhibition, and decision-making were tested after a night of mission-driven total sleep deprivation. The Iowa Resilience to Sleeplessness Test (iREST) Cognitive Subscale, which measures subjective cognitive resilience to sleep loss, was administered after a week of recovery sleep. A receiver operating characteristic (ROC) curve was used to determine whether the iREST Cognitive Subscale can discriminate between gene carriers, and a cutoff score was determined. Cognitive performance after sleep deprivation was compared between those below/above the cutoff score using t-tests or Mann-Whitney U tests.

Results
The iREST discriminated between allele variations for COMT (ROC=.65,SE=.07,p=.03), with an optimal cutoff score of 3.03 out of 5, with 90% sensitivity and 51.4% specificity. Soldiers below the cutoff score had significantly poorer for psychomotor vigilance reaction time (t=-2.39,p=.02), response inhibition errors of commission (U=155.00,W=246.00,p=.04), and decision-making reaction time (t=2.13,p=.04) than Soldiers above the cutoff score.

Conclusion
The iREST Cognitive Subscale can discriminate between those with and without specific vulnerability/resilience-related genotypes. If these findings are replicated, the iREST Cognitive Subscale could be used to help military leaders make decisions about proper personnel placement when sleep loss is unavoidable. This would likely result in increased safety and improved performance during military missions.

Support (if any)
Support for this study came from the Military Operational Medicine Research Program of the United States Army Medical Research and Development Command.
299 Limited Time for Sleep in Night Shift Workers is associated with Risk of Insomnia and Shift Work Disorder
Authors: Lammers-van der Holst Heidi , Zhang Yuan , Barger Laura , Wise John , Murphy Audra , Desnoyers Brian , Qadri Salim , Ronda Joseph , Duffy Jeanne 
Published: May 2021

Abstract

Introduction
Sleep deficiency is a severe problem faced by night shift workers. Approximately one-third of night workers report insomnia during daytime sleep and excessive sleepiness during nighttime work; when severe, these symptoms characterize shift work disorder (SWD). Difficulty sustaining 7 to 9 hours of sleep during the daytime is partly due to a circadian drive for wakefulness. Not much is known, however, about how non-work activities contribute to the inability to obtain recovery sleep. We sought to explore how much time night workers are able to allocate for daytime sleep, and how this relates to insomnia-like symptoms and the likelihood of developing SWD.

Methods
Night shift workers (n=452, 19–69 years old, 54% men) from various occupations who worked at least four night shifts per month completed an online survey. This included questions related to shift duration, hours per workday of non-optional non-work activities, self-rated sleep need, the Insomnia Severity Index (ISI) and a validated 4-item SWD screening questionnaire. For each participant, we calculated the duration of work plus non-optional activities and compared the remaining available time for sleep to their self-described sleep need. Non-parametric Chi-square analyses and Pearson correlations were conducted.

Results
On average, shift duration was 8.9±1.6 hours, non-optional activities were 3.6±2.9 hours, and sleep need was 7.6±1.6 hours, leaving 15% of shift workers with insufficient free time to obtain the amount of sleep they needed. The percentage of workers at high risk for SWD was significantly greater among those who did not have enough free time for sleep compared to those whose schedules allowed sufficient sleep time (72% vs. 42%; χ2=20.2, p&lt;0.0001). We also found that shift workers with insufficient free time for sleep reported higher insomnia severity (r2=-0.20, p&lt;0.0001).

Conclusion
About 15% of night workers have non-optional activities outside work that limit their time to obtain sufficient sleep, and this contributes to greater insomnia-like symptoms and increased risk for SWD. Future research should focus on understanding what these non-optional activities are and whether they differ between night and day workers. These insights will enable personalized countermeasures to maximize the sleep and health of shift workers.

Support (if any)
Supported by US NIH grant R01-AG044416.