bluuebunny/crossref_metadata_2025_split huggingface dataset:
0175 Sleep characteristics in older adults and the risk of Alzheimer’s Disease mortality: The NIH-AARP Diet and Health Study
Authors: Schneider Aaron , Moon Chooza , Xiao Qian 
Published: May 2022

Abstract

Introduction
Alzheimer’s Disease (AD) is the most common form of dementia (1) and the 6th leading cause of death in the U.S. (2). Additionally, it is estimated that currently 5 million individuals are living with AD in the U.S. and this number is expected to triple by 2050 (3). Decades of research has identified various risk factors for AD and a wide array of cardiometabolic risk factors, such as hypertension, type 2 diabetes, metabolic syndrome and obesity (4, 5, 6, 7). Several behavioral factors have also been suggested to play a protective role against AD, including Mediterranean-type diet (8), physical activity (9), and cognitively stimulating activities (10, 11). More recently, growing evidence has pointed sleep deficiency as a modifiable risk factor for AD. (12).

Methods
The purpose of our study was to determine if sleep and napping were associated with AD mortality. We used data from the NIH-AARP Diet and Health Study. Sleep duration and napping were self-reported and AD death were ascertained via linkage to the National Death Index. Of 566,398 members (aged 50-71) who completed baseline questionnaire in 1995-1996, 337,373 participants were included (195,656 men and 137,018 women).

Results
Long sleep and napping were both associated with increased AD mortality. Specifically, 9+ hours of sleep was associated with 50% increase (Hazard Ratio 1.50, 95% CI (1.17-1.92)) in AD mortality when compared 7-8 hours, while napping for 1+ hours was associated with 29% increase (1.29 (1.08, 1.55)) when compared to no napping. Results appeared to be stronger in men and remained after removing AD deaths within first 5 years after baseline.

Conclusion
The results of this study showed that 9+ hours sleep duration was associated with a 50% increase in AD mortality risk when compared to people who slept between 7 and 8 hours, particularly in men. Additional longitudinal studies that follow middle-aged adults through death and include objective measures of sleep and AD related biomarkers are needed to further elucidate the mechanisms contributing to cognitive decline and AD death. Such studies would be useful for informing interventions designed to reduce risk of AD and AD-related death.

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0177 Relationship Between Sleep Architecture and Age by Gender in Brazil: Baependi Heart Study
Authors: Taporoski Tâmara , Beijamini Felipe , Alexandria Shaina , Zumpf Katelyn , von Schantz Malcolm , Pereria Alexandre , Knutson Kristen 
Published: May 2022

Abstract

Introduction
Sleep stage duration has been associated with age. However, few studies have examined sleep stages across adulthood in both men and women. The objective of this analysis was to describe sleep architecture across age by gender in a large cohort of Brazilian adults.

Methods
This ancillary study added polysomnography (PSG) recordings to the Baependi Heart study, a prospective family-based cohort of Brazilian adults. Preliminary analyses used data from 812 participants (517 women). Sleep was staged following standard criteria. Generalized linear models were used to assess associations between age (cubic polynomial) and sleep outcomes in analyses stratified by gender.

Results
Age ranged between 18 and 88 years. Mean age was 50.0 (SD = 13.3) for women and 49.9 (SD = 14.9) for men. Expected means for women at age 50 were 6.35 hours total sleep time (TST) (95% CI: 6.22, 6.48), 213.5 minutes in N2 (95% CI: 207.2, 219.9), and 75.6 minutes (95% CI: 71.9, 79.3) in REM. These were similar to expected means for men at age 50, which were 6.3 hours TST (95% CI: 6.12, 6.48), 212.9 minutes in N2 (95% CI: 204.0, 221.8), and 78.3 minutes (95% CI: 73.7, 82.8) in REM. Expected N3 at 50 years was higher in women (44.7 minutes i, 95% CI: 44.0, 45.5) than men (30.2 minutes,95% CI: 29.4, 31.1) and WASO duration was lower for women (62.6 minutes; 95% CI: 61.7, 63.5) than for men (69.8 minutes; 95% CI: 68.5, 71.1).Non-linear relationships with age were demonstrated for N3, REM, and WASO. For example, in women there appears to be a steeper decline in N3 between approximately ages 20-40 years, a plateau until approximately 55-60 years and then another decline. Men also exhibit a steeper decline at younger ages followed by a more gradual decline that begins around 35-40 years. By contrast, TST showed a stable, linear decline with age in men and women.

Conclusion
Preliminary analyses suggest that the relationship between age and some sleep outcomes differ by gender. Future analyses on the full sample will consider splines for age to investigate further these non-linear relationships.

Support (If Any)
1R01HL141881
0180 Sex Differences in the Association between Mood and Actigraphic Sleep Variability in Adolescents
Authors: Mathew Gina , Reichenberger David , Master Lindsay , Buxton Orfeu , Chang Anne-Marie , Hale Lauren 
Published: May 2022

Abstract

Introduction
Poor mental health in adolescents has been linked to more variable sleep. However, most studies use self-reported measures of sleep. There is also a lack of research on sex differences in these associations, which is important given that poor emotional health is more common in female than male adolescents. The current study examined whether sleep variability measured through actigraphy was associated differently with self-reported mood in female versus male adolescents in between-person analyses.

Methods
Data were collected from a micro-longitudinal substudy of the age 15 wave of the Fragile Families and Child Wellbeing Study. Adolescents wore a wrist-actigraphy device and completed daily surveys for approximately one week (mean=5.6 actigraphy days; n range: 577-604 depending on the mood variable) where they reported levels of loneliness, happiness, excitement, and anger on a five-point Likert scale (0, not at all, to 4, extremely). Separate mixed models assessed whether sex moderated the association between mean mood and actigraphy-measured sleep variability measures including residual standard deviation (riSD) of sleep duration, onset, and offset; sleep regularity index (SRI), and social jetlag (|midpoint of sleep on school nights – midpoint of sleep on free nights|; n for social jetlag ranged from 363-376 depending on the mood variable).

Results
In both sexes, greater average happiness (β=−.11, p=.009) and excitement (β=−.11, p=006) were associated with less variability in sleep duration, and greater average excitement was associated with higher SRI (β=.13, p=.001). Male adolescents reporting greater average happiness and excitement had less variability (riSD) in sleep onset (happiness β=−.15, p=.008; excitement β=−.14, p=.016) and lower levels of social jetlag (happiness β=−.25, p&lt;.001; excitement β=−.22, p=.005), but these associations were null in female adolescents (all p&gt;.20). Neither loneliness nor anger were associated with sleep variability measures in either sex (all p&gt;.15).

Conclusion
Greater positive moods are associated with lower sleep variability, which may protect mental and physical health. Boosting positive mood in adolescents may assist in normalizing sleep schedules, and decreasing sleep variability may aid in the maintenance of positive emotional health, particularly for males. Future research may use a within-participant design to examine the direction of these associations.

Support (If Any)
R01HD073352
0182 Childhood sleep is longitudinally associated with adolescent alcohol and marijuana use
Authors: Krishnan Akshay , Reichenberger David , Strayer Stephen , Master Lindsay , Buxton Orfeu , Hale Lauren , Chang Anne-Marie 
Published: May 2022

Abstract

Introduction
Worse sleep health has been linked with greater substance use among adolescents. However, most studies have only cross-sectionally examined this relationship or examined these longitudinal effects in children with sleep disorders. This study investigates whether childhood sleep is longitudinally associated with adolescent alcohol or marijuana use.

Methods
We analyzed data from the Fragile Families and Child Wellbeing Study, a longitudinal birth cohort. Parents reported their child’s bedtime at ages 3, 5, and 9, and their child’s average sleep duration at ages 5 and 9. At age 15, adolescents self-reported their bedtime, time in bed, whether they ever drank alcohol without parents, and whether they ever tried marijuana. Only participants with complete data were included (N=1,493). Logistic regression analyses for each substance use outcome were adjusted for age, sex, race, family socioeconomic status, family structure, and caregiver education level.

Results
Later bedtime at age 3 was longitudinally associated with lower odds of ever drinking alcohol at age 15 (OR=0.73, CI=0.58, 0.91, p&lt;0.01) whereas later bedtime at age 9 was associated with greater odds (OR=1.44, CI=1.10, 1.89, p&lt;0.01). Later bedtime at age 15 was cross-sectionally associated with greater odds of ever drinking alcohol (OR=1.40, CI=1.23, 1.59, p&lt;0.01). Later bedtime at age 5 was associated with greater odds of ever trying marijuana (OR=1.25, CI=1.00, 1.57, p&lt;0.05), as was later bedtime at age 15 (OR=1.34, CI=1.19, 1.51, p&lt;0.01). Additionally, longer sleep duration at age 9 was longitudinally associated with lower odds of ever trying marijuana (OR=0.84, CI=0.74, 0.97, p&lt;0.02). Adolescents who had longer time in bed at age 15 had lower odds of ever drinking alcohol (OR=0.72, CI=0.63, 0.81, p&lt;0.01) and ever trying marijuana (OR=0.89, CI=0.79, 0.99, p&lt;0.04).

Conclusion
In general, earlier bedtimes and longer sleep duration during childhood and adolescence were associated with lower odds of ever using alcohol or marijuana during adolescence. These results are consistent with current literature indicating that healthy sleep is associated with reduced risk-taking behaviors. Future research should further investigate whether sleep patterns across childhood are linked to decision-making and risk-taking behaviors in adolescence.

Support (If Any)
R01HD073352 (to LH), R01HD36916, R01HD39135, R01HD40421
0183 Daily sleep predicts adolescents’ next-day psychomotor vigilance, sleepiness, and fatigue: Ecological momentary assessment across 28 days of school and vacation
Authors: Shen Lin , Sletten Tracey , Wiley Joshua , Bei Bei 
Published: May 2022

Abstract

Introduction
Few studies have examined the associations between daily sleep and daytime functioning in adolescents during naturalistically-occurring constrained (school term) and unconstrained (vacation) sleep opportunities.

Methods
Adolescents (n = 205; 54.1% females, age M ± SD = 16.9 ± 0.87 years) completed daily measures of sleep and daytime functioning over 28 continuous days (2-week school, and the subsequent 2-week vacation). Total sleep time (TST) and sleep efficiency (SE) were measured using actigraphy and sleep diary. Participants self-reported sleepiness and fatigue every morning and afternoon, and completed the brief, 3.2-minute psychomotor vigilance task (PVT; Joggle Research) on an iPad every afternoon. Using cross-lagged multilevel models, daily TST and SE were examined as predictors of next-day sleepiness, fatigue, and PVT performance. The associations did not differ between school and vacation. The non-significant interaction terms were dropped, and school/vacation status was maintained as a covariate. Previous-day outcome, day of the week, study day, school/vacation and sociodemographics were adjusted. Between-person associations (differences between individuals) and within-person associations (daily deviations from individual’s own mean capturing whether nights with longer- or better-than-average TST or SE respectively, relative to the individual’s average TST/SE, predict next-day outcomes) were tested simultaneously.

Results
Adolescents performed better on the PVT (faster reaction time and fewer lapses) following nights with longer-than-average TST (actigraphy and diary, p-values ≤ .044). Longer-than-average TST (actigraphy and diary) and higher diary SE also predicted lower self-reported sleepiness the next day (morning and afternoon, p-values ≤ .002). Similarly, longer-than-average TST and higher-than-average SE predicted lower self-reported fatigue the next day (morning and afternoon, all p-values ≤ .032). Compared to the vacation, school term was associated with higher self-reported fatigue in the morning and afternoon (p-values ≤ .014), but not higher sleepiness or poorer PVT performance.

Conclusion
Fluctuations in daily sleep were associated with adolescents’ next-day functioning. Importantly, longer- and better-than-average sleep consistently predicted better daytime functioning the next day. Findings were consistent across objective sustained attention and self-reported sleepiness and fatigue, highlighting the short-term effects of sleep restriction on adolescents’ daytime functioning. Protecting adolescents’ sleep duration and promoting good quality sleep on a daily basis could support optimal daytime functioning.

Support (If Any)
Dr Shen was supported by the Monash International Postgraduate Research Scholarship and Monash Graduate Scholarship.
0185 N2 Sleep Spindle Activity is Associated with Better Next-Day Emotion Regulation in Healthy Children
Authors: Myers Annika , Alfano Candice , Rech Megan , Baran Bengi , Palmer Cara 
Published: May 2022

Abstract

Introduction
Children's day-to-day mental health is dependent on adequate quantity and quality of sleep, but far less is known about the microstructural sleep features that support emotional functioning in children. NREM sleep spindles (rhythmic EEG oscillations between 10 and 15 Hz) are closely linked with intellectual abilities and cognitive processing, and have also been shown to relate to children’s emotional behavior, both concurrently and longitudinally. For example, socially-anxious youth showed reduction in sleep spindle activity compared to healthy controls, which correlated negatively with subjective reports of arousal in response to negative images (Wilhelm et al., 2017). In younger children, greater NREM 2 spindle density was associated with greater prosocial behavior concurrently and fewer behavioral and social problems one year later (Mikoteit et al., 2012; 2013). However, studies in pediatric samples are limited overall and haven’t examined spindles in relation to objective measures of emotion regulation.

Methods
We examined relationships between spindle activity during NREM stage 2 (N2) and next-day subjective and objective emotional responses among N=26 healthy children, 7-11 years old. Children completed a full-night of at-home PSG monitoring (10hr sleep opportunity) followed by two in-lab tasks. In task 1, children rated arousal/reactivity in response to negative images from the International Affective Pictures System (IAPS). In task 2, respiratory sinus arrhythmia (RSA) was measured while children were directed to suppress all facial expressions of emotion (i.e., regulate emotional responses to negative content) while watching negatively-valenced movie clips. All analyses controlled for total sleep time on PSG night and RSA analyses controlled for a resting baseline period.

Results
Greater C3 spindle count (r = .51, p &lt; .05) and density (r = .53, p &lt; .05) were significantly associated with less child-reported arousal towards negative images. Greater F3 peak spindle frequency was positively associated with higher RSA during negative movies (r = .54, p &lt; .05), suggesting better regulatory control of emotional responses to correspond with greater spindle peak frequency.

Conclusion
Together with previous data, our findings suggest that sleep spindle activity may partially reflect children’s capacity to regulate emotional responses in relation to stressful situations, thereby potentially reducing risk of mental health problems.

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0188 Associations between Preschoolers’ Behavioral Difficulties and Variability in Sleep Duration and Bedtime
Authors: Burkart Sarah , Armstrong Bridget 
Published: May 2022

Abstract

Introduction
Variability in children’s sleep patterns has been linked with health outcomes including obesity, poor mood, and behavioral difficulties. However, much of this evidence stems from parent-reported measures of sleep. Understanding these associations in preschool-age children using device-based measures is important as sleep habits tend to develop and stabilize during this time. The purpose of this study was to examine associations between parent-reported behavioral difficulties and device-measured sleep among preschoolers.

Methods
Ninety-five preschool-aged children (3-5 years, 51% female, 30% Black) with at least two valid nights of sleep were in included in this analysis. Children were asked to wear an Axivity AX3 accelerometer on their non-dominant wrist for 30 days. Parents completed the Strengths and Difficulties Questionnaire which assessed child behaviors over the past 6 months. Raw accelerometry data were processed with GGIR (v2.3). We used MixWild to conduct mixed effects location scale models with a random intercept and scale predicting nocturnal duration variability and bedtime variability. Time invariant behavior subscales (conduct problems, hyperactivity/inattention, peer relationship problems, emotional symptoms, prosocial behavior, and total difficulties) were included as predictors of child sleep duration and bedtime variability.

Results
Children had an average of 13.4 ± 7.4 (range 2-29) nights of valid data. Average nocturnal sleep duration was 9.7 ± 1.4 hours and average bedtime was 9:48 PM. There were no statistically significant associations between any SDQ subscales and variability in children’s sleep duration and bedtime. There was an association between random location and scale such that participants with later average bedtimes also had more variability in their bedtime (p &lt; 0.001).

Conclusion
Variability in nocturnal sleep was not associated with parent reported behavioral difficulties, which is contrary to recent findings. It is unclear if sleep duration and bedtime variability are associated with day-level changes in children’s behavior. Additional work that emphasizes aspects of sleep beyond sleep duration is needed to advance our understanding of preschool-age children’s sleep.

Support (If Any)
This was supported by the National Institute of General Medical Sciences of the NIH for the UofSC Research Center for Child Well-Being (P20GM130420) and by the National Heart, Lung, and Blood Institute (F32HL154530).
0193 Moving While Sleeping: On the Paradoxical Co-occurrence of Muscle Atonia and Twitching
Authors: You Zipeng , Sokoloff Greta , Blumberg Mark 
Published: May 2022

Abstract

Introduction
During active (or REM) sleep, discreet, jerky movements called myoclonic twitches occur against a background of muscle atonia. The neural mechanisms that allow these two seemingly contradictory phenomena to co-occur remain unclear. One view holds that twitches are produced when a large descending motor signal overpowers the inhibition on spinal motor neurons. An alternative view is that atonia and twitching are coordinated by the same brainstem structures that produce and regulate active sleep. One such structure is the sublaterodorsal tegmental nucleus (SLD), which plays a key role in adult rats to the production of atonia, but whose contribution to twitching has not been examined. Here, we investigated the relationship of SLD neurons to atonia and twitching during a period in early development when twitching is abundant.

Methods
We recorded extracellular neural activity from the SLD in 8 12-day-old (P12) head-fixed rats as they cycled freely between sleep and wake. To assess the relationship between twitches and neural activity, we also recorded limb movements using high-speed video.

Results
Consistent with the adult literature, the majority of SLD neurons (35/56) were significantly more active during periods of sleep-related atonia. Interestingly, a subgroup of neurons (n=15) was inhibited at the onset of a burst of twitches, whereas another subgroup of neurons (n=26) was excited around the onset of a burst of twitches. Thus, together, the activity of 41 of 56 SLD neurons was modulated by twitches.

Conclusion
These results demonstrate that the activity of SLD neurons is associated with both atonia and twitching. This finding suggests that these two early-developing components of active sleep are coordinated within the brainstem. These initial findings open new avenues for further research into the neural mechanisms that coordinate the co-occurrence of twitching and atonia during active sleep.

Support (If Any)
This research was supported by R37-HD081168 awarded to M.S.B.
0197 Increased Brain Kynurenic Acid Elicits Sex-Dependent Abnormalities in NREM Sleep Spindle Dynamics
Authors: Rentschler Katherine , Tentor Zachary , Fox Julie , Pocivavsek Ana 
Published: May 2022

Abstract

Introduction
Sleep spindles are thalamocortical oscillations which occur during non-rapid eye movement (NREM) sleep. NREM sleep spindle aberrations are a consistent clinical sleep deficiency associated with psychotic disorders and exacerbation of cognitive symptoms. Kynurenic acid (KYNA), a tryptophan metabolite synthesized from kynurenine via kynurenine aminotransferases (KATs) and modulator of glutamatergic and cholinergic neurotransmission, is elevated in the brain of patients with psychotic disorders, including schizophrenia and bipolar disorder. Currently, we sought to understand the neurodevelopmental and transient impacts of brain KYNA elevation on sleep spindle dynamics.

Methods
In Experiment #1, sleep spindles were evaluated in adult offspring, postnatal day (PD) 56 from embryonic kynurenine (EKyn) treated rat dams (Rentschler et al., 2021 Sz Bull) (N=7-9 per group). EKyn KYNA male, but not female, offspring have elevated KYNA during the light phase (Wright et al., 2021 Frontiers in Psychiatry). In Experiment #2, sleep spindles were evaluated in adult rats injected with kynurenine (100 mg/kg; i.p.) to acutely elevate brain KYNA levels at zeitgeber time 0 (N=8-12 per group). Polysomnography was recorded via EEG/EMG telemetry. Sleep spindles were evaluated using a custom-made manual scoring system during the first 4 hr of the light cycle.

Results
Male EKyn, but not female, exhibited a decrease in spindle density compared to ECon (2-wayANOVA: ***P&lt;0.001). FFT spectral power for peak spindle frequency (10-15 Hz) was reduced for all EKyn offspring (3-way ANOVA; frequency x treatment interaction: ****P&lt;0.0001; treatment: *P&lt;0.05). Kynurenine challenge reduced spindle density for both sexes (2-way ANOVA: ***P&lt;0.001; M: **P&lt;0.01; F: *P&lt;0.05). Frequency x treatment interaction for males (2-way ANOVA: ***P&lt;0.001) was observed with lower FFT spectral power for 10-10.5 Hz (*P&lt;0.05) and greater power for 14-14.5 Hz (*P&lt;0.05).

Conclusion
We determined conspicuous sex differences in spindle dynamics in the EKyn paradigm that may be related to brain KYNA levels; only males exhibited a decrease in spindle density, however all EKyn offspring had reduced FFT spectral power. Kynurenine challenge reduced spindle density in both sexes, however only males had changes in FFT spectral power. Future work will consider the efficacy of KYNA synthesis inhibition to prevent NREM sleep spindle abnormalities induced by KYNA elevation.

Support (If Any)
Funding Source: National Institute of Health Grants: NIH RO1 NS102209 & P50 MH103222.