Sleep Irregularity Research Articles

Sleep timing, sleep regularity, and psychological health in early late life women: Findings from the Study of Women's Health Across the Nation (SWAN)

ObjectivesTo examine the associations of actigraphy-assessed sleep timing and regularity with psychological health in early late life women, whose circadian rhythms may be impacted by aging. DesignCross-sectional. ParticipantsA racially/ethnically diverse sample of 1197 community-dwelling women (mean age 65 years) enrolled in the Study of Women's Health Across the Nation. MeasuresActigraphy-assessed sleep measures included timing (mean midpoint from sleep onset to wake-up) and regularity (standard deviation of midpoint in hours). Psychological health measures included a composite well-being score, the Center for Epidemiological Studies Depression Scale, and the Generalized Anxiety Disorder-7 Scale. Linear and logistic regression models, adjusted for covariates (including sleep duration), tested associations between sleep and psychological health measures. ResultsAfter covariate adjustment, a sleep midpoint outside of 2:00-4: 00 AM was significantly associated with depressive symptoms (β = 0.88, 95% CI = 0.06, 1.70) and scoring above the cut-point for clinically significant depressive symptoms (OR = 1.72, 95% CI = 1.15, 2.57). Sleep irregularity was significantly associated with lower psychological well-being (β = -0.18, 95% CI = −0.33, −0.03), depressive (β = 1.36, 95% CI = 0.29, 2.44) and anxiety (β = 0.93, 95% CI = 0.40, 1.46) symptoms, and scoring above the cut-point for clinically significant depressive (OR = 1.68, 95% CI = 1.01, 2.79) and anxiety (OR = 1.62, 95% CI = 1.07, 2.43) symptoms. ConclusionAbove and beyond sleep duration, a sleep midpoint outside of 2:00-4:00 AM was associated with depressive symptoms while sleep irregularity was associated with multiple psychological health domains in late life women.

O040 Associations between Sleep Irregularity and Hypertension: Sleep Sensor Data from Over Two Million Nights

Abstract Introduction Irregular sleep has been associated with worse cardio-metabolic health compared to regular sleep, but prior studies are limited in sample size and have assessed sleep irregularity over short assessment periods (7-14 days). This study investigated associations between sleep irregularity and hypertension in a large, global sample over multiple months. Methods Data from 12,300 participants (Mean ± SD; 50 ± 12 years, 12% females) who used an under-mattress sleep device and a portable blood pressure monitor between July 2020 and March 2021 were included. Each participant had ~180 nights of recordings and ~70 blood pressure entries. Sleep duration regularity was assessed as the standard deviation of device-assessed total sleep time. Sleep timing regularity was assessed as the standard deviation of sleep onset time and sleep midpoint. Logistic regressions were conducted, controlling for age, sex, BMI, and mean total sleep time. Results Across total sleep time quartiles, sleep duration irregularity was consistently associated with a 9-15% increase in hypertension risk. A 38-minute increase in sleep midpoint irregularity was associated with an 11% (1.11 [1.03, 1.20]) increase in hypertension risk, independent of mean total sleep time and mean sleep midpoint. Similarly, a ~31-minute increase in sleep onset time irregularity was associated with a 29% increased risk of hypertension (1.29 [1.18, 1.42]). Conclusions Irregular sleep, regardless of average total sleep time, was associated with increased hypertension risk. Further assessment of day-to-day fluctuations in sleep duration and timing for potential effects on next-day blood pressure and cardiovascular health outcomes is warranted.

Irregular sleep and all-cause mortality: A large prospective cohort study

ObjectivesPrevious studies using objective parameters have shown that irregular sleep is associated with the disease incidence, progression, or mortality. This study aimed to determine the association between subjective sleep duration and sleep regularity, with mortality in a large population. MethodsParticipants were from the Japan Multi-Institutional Collaborative Cohort study. We obtained information from each participant on sleep duration, sleep regularity, and demographics and overall lifestyle using self-administered questionnaires. We defined sleep regularity according to participants' subjective assessment of sleep/wake time regularity. Participants (n = 81,382, mean age: 58.1 ± 9.1years, males: 44.2%) were classified into 6 groups according to sleep duration and sleep regularity. Hazard ratios (HR) for time-to-event of death were calculated using the Cox proportional hazards model. ResultsThe mean follow-up period was 9.1 years and the mean sleep duration was 6.6 h/day. Irregular sleep significantly increased the risk of all-cause mortality in all models compared with regular sleep (HR 1.30, 95% confidence interval; CI, 1.18-1.44), regardless of sleep duration. Multivariable analysis of the 6 groups by sleep pattern (sleep regularity and duration) showed irregular sleep and sleep durations of <6 h/day, 6 to <8 h/day, or ≥8 h/day were associated with a 1.2-1.5-fold increases in mortality, compared to regular sleep and sleep duration of 6 to <8 h/day. ConclusionsOur study shows an association between sleep irregularity and all-cause mortality in a large Japanese population. Our findings provide further confirmation of the need to consider not only sleep duration, but also the regularity aspect of sleep schedules.

Sleep duration irregularity is associated with elevated blood pressure in young adults

ABSTRACT Sleep irregularity (i.e., highly variable sleep patterns) is an emerging risk factor for cardiometabolic disease. Though irregular sleep patterns are common among young adults, the cardiometabolic health (CMH) repercussions of sleep irregularity in this population are unclear. We examined associations between sleep duration and irregularity with measures of CMH in 44 (24 M/20 F, 23 ± 5y, BMI 26 ± 4 kg/m2, blood pressure (BP): 125/71 ± 14/9 mmHg) young adults. Participants wore actigraphy monitors for seven-days and sleep duration irregularity was operationalized as the standard deviation of nightly sleep duration (sleep SD). CMH variables of interest included brachial and aortic BP, arterial stiffness (cf-PWV), augmentation index (AIx75), and fasting blood glucose and lipids. Associations between sleep duration and sleep SD with CMH variables were assessed via correlations adjusted for sex and BMI. Sleep duration generally was not associated with CMH indices. However, sleep SD was associated with brachial systolic (r = 0.433, p = .027) and diastolic BP (r = 0.415, p = .035). Similarly, sleep duration SD was associated with aortic systolic BP (r = 0.447, p = .022). Our findings show that sleep irregularity, but not duration, is associated with higher brachial and central BP in young adults. Abbreviations: AIx75: augmentation index at a heart rate of 75 beats per minute; BP: blood pressure; CMH: cardiometabolic health; cf-PWV: carotid-femoral pulse wave velocity; DXA: dual x-ray absorptiometry; mg/dl: milligrams per deciliter; PWA: pulse wave analysis; PWV: pulse wave velocity; sleep duration SD: standard deviation of nightly sleep duration

Pandemic and student mental health: mental health symptoms among university students and young adults after the first cycle of lockdown in the UK.

Early COVID-19 research suggests a detrimental impact of the initial lockdown on young people's mental health. We investigated mental health among university students and young adults after the first UK lockdown and changes in symptoms over 6 months. In total, 895 university students and 547 young adults not in higher education completed an online survey at T1 (July-September 2020). A subset of 201 university students also completed a 6 month follow-up survey at T2 (January-March 2021). Anxiety, depression, insomnia, substance misuse and suicide risk were assessed. At T1, approximately 40%, 25% and 33% of the participants reported moderate to severe anxiety and depression and substance misuse risk, clinically significant insomnia and suicidal risk. In participants reassessed at T2, reductions were observed in anxiety and depression but not in insomnia, substance misuse or suicidality. Student and non-student participants reported similar levels of mental health symptoms. Student status was not a significant marker of mental health symptoms, except for lower substance misuse risk.Cross-sectionally, greater symptoms across measures were consistently associated with younger age, pre-existing mental health conditions, being a carer, worse financial status, increased sleep irregularity and difficulty since lockdown. Longitudinally, T2 symptoms were consistently associated with worse financial status and increased difficulty sleeping at T1. However, these associations were attenuated when baseline mental health symptoms were adjusted for in the models. Mental health symptoms were prevalent in a large proportion of young people after the first UK lockdown. Risk factors identified may help characterise high-risk groups for enhanced support and inform interventions.

0204 Sleep Irregularity Is Associated with Increased Risk of Hypertension: Data From Over Two Million Nights

Abstract Introduction Sleep irregularity has been associated with worse cardio-metabolic health compared to regular sleep, but prior studies have been limited in sample size and have assessed sleep irregularity by actigraphy or questionnaires over a relatively short duration (~ 14 days). The current study investigated associations between sleep regularity and hypertension in a large, global sample over multiple months. Methods Data from 12,300 participants (aged 18-90 years) who used an under-mattress sleep device and a portable blood pressure monitor between July 2020 and March 2021 were included in this study. Sleep duration regularity was assessed as the standard deviation via device-assessed total sleep time. Sleep timing regularity was assessed as the standard deviation in sleep onset time and in sleep midpoint. Logistic regressions controlling for age, sex, BMI, and mean total sleep time were conducted to investigate potential associations between sleep regularity and hypertension. Results Participants were typically middle-aged (Mean ± SD; 50 ± 12 years) and predominantly male (12% females). Each participant had ~180 nights of recordings and ~70 blood pressure entries. There were 2,499 cases of hypertension defined as SBP&amp;gt;140 and/or DBP &amp;gt;90mmHg (20% of the sample). Across total sleep time quartiles, high sleep duration irregularity was consistently associated with a 9 to 15% increase in hypertension risk. A 38-minute increase in sleep midpoint irregularity was associated with an 11% (1.11 [1.03, 1.20]) increase in hypertension risk, independent of mean total sleep time and mean sleep midpoint. Similarly, a ~31-minute increase in sleep onset time irregularity was associated with a 29% increased risk of hypertension (1.29 [1.18, 1.42]). Conclusion These novel findings provide insight into the potential important impact of sleep irregularity on cardiovascular health. Further assessment of day-to-day fluctuations in sleep duration and timing for potential effects on next-day blood pressure and other cardiovascular health outcomes are warranted. Support (If Any) This was an unfunded investigator-initiated study. De-identified data were provided by Withings for unrestricted investigator-led analysis. PE serves as a consultant for Withings.

0031 Sleep Regularity is Associated with DNA Methylation in Cognitive, Cardiovascular and Mood-related Genes: A GWAS-informed Study in Adolescents

Abstract Introduction Adolescence is associated with a delay in the circadian timing of sleep. However, social factors prevent adolescents from adapting to a later sleep-wake pattern, leading to different forms of circadian misalignment that may increase the risk of cardiovascular and mental health disorders. Several GWAS have identified genes associated with sleep and circadian phenotypes, however, little is known regarding the epigenetic basis and significance of sleep timing and its regularity in adolescence. Methods We analyzed data from 230 adolescents from the Penn State Child Cohort follow-up study who provided a blood sample for DNA extraction and had complete at-home 7-night (at least 3) actigraphy (ACT) data. ACT-measured sleep midpoint was calculated as the intra-individual mean of the 7-night midpoint (zeroed to midnight) of the sleep period. ACT-measured sleep regularity was calculated as the intra-individual standard deviation of the 7-night sleep midpoint. Epigenome-wide single nucleotide resolution of DNA methylation in cytosine-phosphate-guanine (CpG) sites and surrounding regions were obtained from peripheral leukocytes. This study focuses on methylation sites in GWAS-informed genes previously associated with sleep and circadian phenotypes. Linear regression assessed the association between sleep midpoint and sleep regularity with site-specific methylation levels, adjusting for sex, age, race/ethnicity, body mass index, and psychotropic medication use. Using the Benjamini &amp; Hochberg method to adjust for a false discovery rate. Adjusted p-values are reported as q-values. Results Sleep midpoint was not associated with a significant change in methylation at any of the measured intragenic sites. Sleep regularity was significantly associated with differential methylation at 238 intragenic sites in 147 genes with an adjusted p&amp;lt;0.05, of which, three sites were within GWAS-informed sleep/circadian-related genes. Higher sleep irregularity was associated with hypermethylation in MAD1L1 (q=2.4x10-2) and with hypomethylation in CALN1 (q=3.8 x 10-4) and ZNF618 (q=3.8 x 10-2). Conclusion Sleep irregularity is associated with altered DNA methylation in genes previously identified in GWAS of sleep/circadian phenotypes. Our data provides evidence for a potential epigenetic link between sleep irregularity and genes involved in neurocognitive functioning (CALN1), internalizing disorders (MAD1L1) and blood pressure (ZNF618). Support (If Any) National Institutes of Health (R01HL136587, R01MH118308, UL1TR000127)

0219 Interplay of School Days and Free Days with Sleep Midpoint on the Association of Visceral Adiposity with Blood Pressure in Adolescents

Abstract Introduction The circadian timing of sleep, including its variability, has emerged as an important contributor to obesity and cardiovascular health, such as elevated blood pressure. Adolescence is a particularly vulnerable period for circadian misalignment, which may express differently if youth are in school or on free-days. We examined whether deviations in sleep midpoint increase the impact of visceral adiposity on elevated blood pressure in adolescents as a function of being entrained to school or not. Methods We analyzed cross-sectional data from the Penn State Child Cohort follow-up study, a random population-based sample of 303 adolescents (16.2 ± 2.2 y; 47.5% female; 21.5% minority). Actigraphy-measured sleep midpoint was calculated as the midpoint (zeroed to midnight) of the sleep period for weekdays (5-nights) and weekends (2-nights). Actigraphy-measured sleep regularity was calculated as the intra-individual standard deviation of the 5-night weekdays sleep midpoint. Visceral adipose tissue (VAT) was measured via dual-energy X-ray absorptiometry scan. Systolic (SBP) and diastolic (DBP) blood pressure was measured three times in the seated position. Multivariable linear regression models were stratified by “in school” and “on break” to test sleep midpoint and sleep regularity as effect modifiers of VAT on SBP/DBP levels. Analyses were adjusted for sex, race/ethnicity, age, actigraphy-measured sleep duration and polysomnography-measured apnea/hypopnea index. Results When participants were studied while “in school”, significant interactions were found between VAT and weekdays sleep midpoint on SBP (p-interaction=0.027) and DBP (p-interaction=0.046), so that the later the sleep midpoint on school days, the greater the association of VAT with SBP/DBP. When participants were studied while “on break”, a significant interaction was found between VAT and weekdays sleep regularity on SBP (p-interaction=0.039), so that the higher the sleep irregularity on weekdays, the greater the association of VAT with SBP. No other significant interactions were found. Conclusion A delayed and an irregular sleep midpoint during school days and during breaks, respectively, best identified those adolescents with greater cardiovascular risk associated with visceral obesity. These data suggest that not only the circadian timing of sleep contributes to adverse cardiovascular outcomes but its distinct biomarkers require measurement under different entrainment conditions in adolescents. Support (If Any) National Institutes of Health (R01HL136587, UL1TR000127)

Subjective irregular sleep is associated with metabolic syndrome: A cross-sectional study

Several studies have been reported that sleep duration and circadian rhythms are associated with metabolic syndrome (MetS). However, there are few studies of a relationship between sleep and MetS based on subjective evaluation of sleep regularity. The aim of this study is to examine the relationship between subjective sleep irregularity and metabolic syndrome.This cross-sectional study included 3,880 participants (1,383 males, 2,497 females) from 2013 to 2017, and we use a self-administered questionnaire to acquire information about sleep (sleep regularity, duration and bedtime). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression analyses to evaluate the associations between sleep regularity and the prevalence of MetS.The irregularity of sleep was significantly associated with MetS (OR 1.231, 95% CI 1.101–1.375) adjusted for age, sex, METs, sleep duration, bedtime, drinking and smoking statuses, and a history of using sleeping pills. We examined the interaction of MetS with sleep regularity and sleep duration/bedtime, stratified by multiplying the two groups of sleep regularity/irregularity and the three groups of sleep duration/bedtime. Each group of sleep duration/bedtime showed no relationship in the sleep regularity group with MetS, but a significant relationship in the sleep irregularity group. Leptin was significantly elevated in the irregular sleep group regardless of sleep duration and bedtime.Although many studies have shown a link between sleep and MetS especially in terms of sleep duration, this study showed that irregular sleep is more strongly associated with MetS than sleep duration or bedtime.

Free Day, but Not Work Day, Sleep Duration Is Inversely Associated With Aortic Stiffness in Apparently Healthy Young Adults

Insufficiency or irregularity in sleep is associated with high blood pressure (BP) and aortic stiffness, both of which are independent predictors of all‐cause and cardiovascular mortality. The cardiovascular ramifications of short and irregular sleep are well documented in shift workers, but the health implications of possible differences between sleep duration on workdays (WD) and free days (FD) in non‐shift workers is less clear.PURPOSEWe sought to examine associations between WD and FD sleep duration, and then to inspect for relationships between WD and FD sleep duration, as well as the difference between WD and FD sleep duration (i.e., sleep irregularity), with BP and indices of arterial stiffness in apparently healthy young adults. We hypothesized 1) participants would sleep less on WD than FD, and 2) that participants with short WD sleep duration would exhibit higher BP and arterial stiffness, and 3) those with greater sleep irregularity would exhibit higher BP and arterial stiffness.METHODS16 apparently healthy young adults (21.8±4.0 yrs; 24.4±2.9 kg/m2; Mean±SD) participated in this study. All participants completed the Munich ChronoType Questionnaire to assess self‐described WD and FD sleep‐wake behavior. WD and FD sleep duration were determined, and sleep irregularity was quantified as the absolute value of the difference between WD and FD sleep duration. Following 10‐min of supine rest, we used an automated oscillometric device (SphygmoCor XCEL) to measure BP and augmentation index (AIx), an indirect measure of arterial stiffness. Aortic stiffness was then assessed using carotid‐femoral pulse wave velocity (cf‐PWV). WD and FD sleep duration were compared using a paired t‐test and associations between sleep with BP and indices of arterial stiffness were assessed using Pearson correlations, or the non‐parametric equivalent for sleep irregularity.RESULTSWD sleep duration was 492±85 min, FD sleep duration was 480±83 min, and sleep irregularity was 53±49 min. Systolic BP was 120±10 mmHg, diastolic BP was 68±7 mmHg, AIx was 10.9±9.8 %, and cf‐PWV was 5.8±0.7 m/s. WD sleep duration was significantly greater (P&lt;0.01) than FD sleep duration, and WD sleep duration was not associated (P&gt;0.05) with systolic BP (r=0.10), diastolic BP (r=0.10), AIx (r=0.07), or cf‐PWV (r=‐0.18). FD sleep duration was inversely correlated with cf‐PWV (r=‐0.65; P=0.01), but was not associated (P&gt;0.05) with systolic BP (r=‐0.12), diastolic BP (r =‐0.08), or AIx (r=0.25). Sleep irregularity was not associated (P&gt;0.05) with systolic BP (r=0.37), diastolic BP (r=0.45), AIx (r=0.08), or cf‐PWV (r=0.14).CONCLUSIONSContrary to our hypothesis, FD, but not WD, sleep duration was associated with aortic stiffness in apparently healthy young adults. Average sleep duration of our cohort exceeded the recommended minimum of 7 hours per night and sleep irregularity was small (i.e., &lt;60 min on average), thus potentially masking elevations in BP and arterial stiffness seen with short and/or irregular sleep such as in shift workers.

Sleep irregularity and nonsuicidal self-injurious urges and behaviors.

The objectives of this study were to examine the relationships between sleep regularity and nonsuicidal self-injury (NSSI), including lifetime NSSI history and daily NSSI urges. Undergraduate students (N = 119; 18-26 years), approximately half of whom endorsed a lifetime history of repetitive NSSI, completed a 10-day actigraphy and ecological momentary assessment (EMA) protocol. A Sleep Regularity Index was calculated for all participants using scored epoch by epoch data to capture rapid changes in sleep schedules. Participants responded to EMA prompts assessing NSSI urge severity and negative affect three times daily over the 10-day assessment period. Results indicate that individuals with a repetitive NSSI history were more likely to experience sleep irregularity than those without a history of NSSI. Findings also suggest that sleep irregularity was associated with more intense urges to engage in NSSI on a daily basis, even after accounting for average daily sleep duration, sleep timing, negative affect, and NSSI history. Neither sleep duration nor sleep timing was associated with NSSI history nor daily NSSI urge intensity. Findings suggest that sleep irregularity is linked with NSSI, including NSSI history and intensity of urges to engage in NSSI. The present study not only supports the growing evidence linking sleep disturbance with the risk for self-injury but also demonstrates this relationship using actigraphy and real-time assessments of NSSI urge severity. Findings highlight the importance of delineating the nuances in sleep irregularity that are proximally associated with NSSI risk and identifying targets for intervention.

Feasibility and the effects of an online mindfulness-based health promotion program on college students' sleep, circadian rhythms, and well-being: Protocol for a randomized trial [CIRCAMIND study

College students are exposed to a stressful routine, circadian misalignment, sleep irregularity and restriction, that is harmful to their health. Mindfulness training promotes well-being, reduces stress, and can improve sleep quality. Therefore, the purpose of this study is to evaluate the feasibility of the Mindfulness-Based Health Promotion (MBHP) program on sleep, circadian rhythms, stress, and mental health in college students. Data about the usability of the online format are still rare in the literature, therefore, we also intend to verify the usability of this format. A randomized controlled trial with four-time points will compare the MBHP program with a sleep psychoeducation control. Recruitment will be done from a database derived from a cross-sectional study previously conducted. Students enrolled in at least one undergraduate course at two Brazilian universities (one public, another private) with poor subjective sleep quality will be randomized and allocated in the ratio 1:1. Primary outcomes will be sleep quality (Pittsburgh Sleep Quality Index, Sleep Hygiene Index, Epworth Sleepiness Scale) and circadian rhythms (Munich Chronotype Questionnaire, actigraphy, 6-sulfatoxymelatonin and 24 h cortisol-profile). Secondary outcomes will be subjective well-being and stress. An additional weekly assessment will be done about the usability of the online mindfulness-based program (ease of use, compatibility, engagement, therapeutic pathway). This is the first study to evaluate the effects of mindfulness on the circadian rhythms and sleep at four-time points. The efficacy of the program confirmation could influence and be considered for an academic policy aimed at promoting health in college students. The results about its usability will also help to highlight the best format for its application.

Abstract MP56: Sleep Regularity Modifies The Association Of Visceral Adiposity With Elevated Blood Pressure In Adolescents

Introduction: Although obesity, insufficient sleep and sleep apnea are known risk factors for elevated blood pressure, the circadian timing of sleep is also involved in metabolic and blood pressure regulation. As a result, sleep irregularity, which is highly prevalent in adolescents, may be a potential risk factor for obesity-related adverse cardiovascular outcomes. Hypothesis: We hypothesize that greater sleep irregularity increases the impact of visceral adiposity on elevated blood pressure in adolescents. Methods: We analyzed cross-sectional data from the Penn State Child Cohort follow-up study, a random population-based sample of 303 adolescents (16.2 ± 2.2 year old; 47.5% female; 21.5% racial/ethnic minority) who had complete at-home 7-night (at least 5) actigraphy (ACT) data and in-lab dual-energy X-ray absorptiometry (DEXA) scan and polysomnography (PSG) data. ACT-measured sleep duration and sleep midpoint were calculated as the intra-individual mean of the 7-night total sleep time and the midpoint (zeroed to midnight) of the sleep period, respectively. ACT-measured sleep regularity was calculated as the intra-individual standard deviation of the 7-night sleep midpoint. DEXA-measured visceral adipose tissue (VAT) was the primary predictor. Systolic (SBP) and diastolic (DBP) blood pressure, measured three times in the seated position, were the primary outcomes. Multivariable linear regression models tested sleep midpoint and sleep regularity as effect modifiers of VAT on SBP/DBP levels, while simultaneously adjusting for sex, race/ethnicity, age, ACT-measured sleep duration and PSG-measured apnea/hypopnea index. Results: Significant interactions were found between sleep regularity and VAT on SBP (p-interaction=0.009) and DBP (p-interaction=0.039), while not between mean sleep midpoint and VAT (p-interactions=0.210 and 0.883). These findings remained valid even after further adjusting for body mass index percentile (p-interactions=0.006 and 0.034). Among adolescents with high sleep irregularity (≥ 45 minutes; n=124), each standard deviation increase in VAT was associated with a 5.55 (0.91) and 3.07 (0.70) mmHg increase in SBP and DBP, respectively (both p&lt;0.001). Among those with low sleep irregularity (&lt; 45 minutes; n=179) VAT was not significantly associated with SBP [0.69 (0.99), p=0.488] or DBP [0.04 (0.77), p=0.956]. Conclusions: An irregular circadian timing of sleep may increase the impact of visceral adiposity on elevated blood pressure in adolescents. These data support that sleep irregularity, independent of sleep apnea and insufficient sleep, may contribute to the development of cardiovascular sequelae associated with central obesity.

Abstract 040: Sleep Regularity And Subclinical Markers Of Cardiovascular Disease: The Multi Ethnic Study Of Atherosclerosis (MESA)

Background: Sleep irregularity has been linked to incident cardiovascular disease (CVD). Less is known about sleep regularity and associations with atherosclerosis. Our objective was to examine associations of sleep regularity with measures of atherosclerosis in the diverse MESA cohort. Methods: Participants from the MESA Sleep Study (2010-2013; N=2,032, Mean age: 68.6 ± 9.2 years; 53% Female, 38% White, 28% Black or African American, 23% Hispanic, 11% Chinese) completed 7-days of actigraphy. At the same exam, coronary artery calcium (CAC) was derived from computed tomography, carotid plaque presence and carotid intima-media thickness (cIMT) were derived from ultrasonography, and the ankle brachial index (ABI) was calculated from extremity measured systolic blood pressure. Sleep regularity was quantified by standard deviations in sleep durations and sleep onset time across wear days and categorized in 30 minute (mins) increments. Adjusted relative risk regression models were used to calculate prevalence ratios (PRs) and 95% confidence intervals (CI) for associations of measures of sleep regularity with each subclinical marker of CVD. Models adjusted for demographics, CVD risk factors, and objectively-assessed obstructive sleep apnea. Results: After multivariable adjustment, and compared to those with regular sleep durations (SD≤60 mins), participants with greater sleep duration irregularity (SD&gt;120 mins) were more likely to have high CAC burden [CAC &gt;300; PR (95% CI): 1.36 (1.03-1.78)], carotid plaque [1.10 (1.00-1.22)] and an abnormal ABI [ABI &lt;0.9; 1.74 (1.00-3.02)]. Compared to participants with regular sleep timing (SD≤30 mins), those with irregular sleep timing (SD&gt;90 mins) were 1.38 (1.04-1.83) times more likely to have high CAC burden. Associations did not vary by age or sex. Conclusion: Sleep regularity, particularly sleep duration regularity, was associated with measures of subclinical CVD in this diverse cohort. Sleep regularity is a modifiable sleep dimension worthy of further investigation.

Accelerometer-derived sleep onset timing and cardiovascular disease incidence: a UK Biobank cohort study.

Growing evidence suggests that poor sleep health is associated with cardiovascular risk. However, research in this area often relies upon recollection dependent questionnaires or diaries. Accelerometers provide an alternative tool for measuring sleep parameters objectively. This study examines the association between wrist-worn accelerometer-derived sleep onset timing and cardiovascular disease (CVD). We derived sleep onset and waking up time from accelerometer data collected from 103 712 UK Biobank participants over a period of 7 days. From this, we examined the association between sleep onset timing and CVD incidence using a series of Cox proportional hazards models. A total of 3172 cases of CVD were reported during a mean follow-up period of 5.7 (±0.49) years. An age- and sex-controlled base analysis found that sleep onset time of 10:00 p.m.-10:59 p.m. was associated with the lowest CVD incidence. An additional model, controlling for sleep duration, sleep irregularity, and established CVD risk factors, did not attenuate this association, producing hazard ratios of 1.24 (95% confidence interval, 1.10-1.39; P < 0.005), 1.12 (1.01-1.25; P = 0.04), and 1.25 (1.02-1.52; P = 0.03) for sleep onset <10:00 p.m., 11:00 p.m.-11:59 p.m., and ≥12:00 a.m., respectively, compared to 10:00 p.m.-10:59 p.m. Importantly, sensitivity analyses revealed this association with increased CVD risk was stronger in females, with only sleep onset <10:00 p.m. significant for males. Our findings suggest the possibility of a relationship between sleep onset timing and risk of developing CVD, particularly for women. We also demonstrate the potential utility of collecting information about sleep parameters via accelerometry-capable wearable devices, which may serve as novel cardiovascular risk indicators.

Day-to-day variation in sleep duration is associated with increased all-cause mortality.

There is a paucity of data on the association between day-to-day variation in sleep pattern and all-cause mortality. We aimed to investigate whether day-to-day variation in sleep duration and onset of sleep are associated with cardiovascular and all-cause mortality. We used data belonging to 388 unique patients from the Midlife in the United States 2 Biomarker study (2004-2009). Information on sleep onset, duration, and sleep-wake cycles was collected for 7 consecutive days using the Actiwatch device. Sleep irregularity was assessed using mean and standard deviations in sleep duration and time of onset of sleep over 7 days. Cox proportional regression analysis and the Fine and Gray subdistribution method were used with all-cause and cardiovascular mortality, respectively. Over a median of 8.6 years of follow-up, 37 patients died, including 10 deaths resulting from cardiovascular causes. There was no statistically significant increase in cardiovascular mortality with variation in sleep duration in the highest vs the lowest tertile (hazard ratio, 4.00; 0.45-35.48; P = .21). However, increased all-cause mortality was seen in the highest vs the lowest tertile (hazard ratio, 3.99; 1.33-11.94; P = .01). Multivariable model adjusting for confounders had higher all-cause mortality with increased sleep duration variation in the highest vs the lowest tertile: hazard ratio, 4.85; 1.52-15.49; P < .01). Day-to-day variation in sleep duration is associated with increased all-cause mortality but not cardiovascular mortality after adjusting for mean sleep duration, inflammation, diabetes, age, body mass index, renal function, and blood pressure. Irregularity in the onset of sleep is not associated with all-cause mortality or cardiovascular mortality. Katamreddy A, Uppal D, Ramani G, etal. Day-to-day variation in sleep duration is associated with increased all-cause mortality. J Clin Sleep Med. 2022;18(3):921-926.

The mediating effect of cognitive appraisal on the relationship between sleep habits and the stress response among Japanese female college students

BackgroundUndergraduate students tend to develop “evening-type” sleep patterns. Recent research has reported that evening-type and irregular sleep habits are related to physical and mental stress responses, particularly in female students. Although the connection between sleep habits and the stress response has been well documented, the mechanism behind this relationship is currently unknown. Using the transactional model as a framework and female students as our target population, we examined whether sleep habits predict the stress response through the mediation of cognitive appraisals of one’s own sleep habits.MethodsThree hundred twenty-one Japanese female college students participated in this study. Participants completed measures of their sleep habits (sleep patterns and sleep irregularity), cognitive appraisals of their sleep habits (including four subscales: commitment, appraisal of influence, appraisal of threat, and controllability), stress responses (depression and anxiety), and control factors. The reliability and validity of the scales used in this study, except for sleep pattern and sleep irregularity, were confirmed in previous studies.ResultsMultiple-mediation-model analysis indicated that commitment mediates the relationship between sleep pattern and anxiety. Meanwhile, cognitive appraisals, as a whole, were found to have a mediating effect on the relationship between sleep irregularity and depression.ConclusionsOur study revealed that cognitive appraisals mediated the relationship between sleep habits and the stress response. The findings also suggest that maintaining a low level of commitment might be effective for reducing anxiety, especially considering the difficulty associated with changing lifestyles. The findings of the present study should be useful for health education related to lifestyle.

Accelerometer-Derived Sleep Onset Timing and Cardiovascular Disease Incidence: A UK Biobank Cohort Study

Background: Growing evidence suggests that various aspects of sleep are associated with cardiovascular risk. However, studies in this area are often based on recollection-dependent questionnaires or diaries. Accelerometers can be used to derive sleep parameters and measure sleep patterns objectively. This study examined the associations between objectively measured sleep onset timing and cardiovascular diseases (CVD). Methods: Data from 103,413 UK Biobank participants that wore an accelerometer on their wrist for seven days were used in this study. We derived sleep onset and waking up time from the raw data, allowing for analysis of sleep timing, sleep duration, and sleep irregularity over this period. From this, we examined the association between sleep onset timing and CVD incidence using a series of Cox proportional hazards models. Findings: 3172 cases of CVD were reported during a mean follow-up period of 5.7 (±0.49) years. An age- and sex-controlled base analysis found that sleep onset time of 10:00pm-10:59pm was associated with the lowest CVD incidence. A fully adjusted model, additionally controlling for sleep duration, sleep irregularity, and established CVD risk factors, was unable to eliminate this association, producing hazard ratios of 1.24 (95% CI, 1.10–1.39; p <0.005), 1.12 (1.01–1.25; p = 0.04), and 1.25 (1.02–1.52; p = 0.03) for sleep onset <10pm, 11:00pm-11:59pm, and ≥12am, respectively, compared to 10:00pm-10:59pm. Importantly, sensitivity analyses revealed this association was largely confined to, and accentuated in, females, with only sleep onset <10pm significant for males. Interpretation: Our findings suggest an independent relationship between sleep onset timing and risk of developing CVD, particularly for women. We also demonstrate the potential utility of collecting information about sleep parameters via accelerometry-capable wearable devices, which may serve as novel cardiovascular risk indicators. Funding: Huma Therapeutics. Declaration of Interest: SN, ABR, ACC, BDO, MA, DM and DP are employees of Huma Therapeutics. Ethical Approval: Participants provided informed consent, and the UKB study received ethical approval from the North West Multi-Centre Research Ethics Committee (REC reference: 16/NW/0382) and was conducted in accordance with the principles of the Declaration of Helsinki. The current analyses were conducted under UKB application number 55668.

637 Cumulative risk associated with poor sleep health in children and adolescents

Abstract Introduction Social risk factors are associated with poor sleep outcomes across the life course. It is unclear if this association varies based on biological factors, such as age and gender. Therefore, the purpose of this analysis was to identify if age or gender moderated the association between cumulative risk and sleep duration/regularity in a national sample of children and adolescents. Methods We completed a secondary data analysis using the National Survey of Children’s Health 2017–2018 publicly available dataset. In a sample of 36,997 children age 6–17 years, we explored the association between a social cumulative risk index score (CRI) and child sleep duration and regularity. We included eight dichotomous social risk variables in the CRI: parental education Results Age was a significant moderator of the association between CRI and short sleep duration, such that the magnitude of the CRI-sleep relationship was greater in school-age children (age 6–11; b = -0.13, p&amp;lt;0.001) compared to adolescents (age 12–17 years; b = -0.05, p&amp;lt;0.001). Age was not a significant moderator between CRI and sleep irregularity. However, CRI independently predicted increased odds of sleep irregularity (OR = 1.30, p&amp;lt;.001) and older age moderately increased the odds of sleep irregularity (OR = 1.21, p = 0.06). Sex was not a significant moderator of the association between CRI and sleep duration or sleep regularity. However, female sex was positively associated with sleep duration (b = 0.06, p = 0.11), but was not a significant independent predictor of sleep irregularity. Conclusion Younger children with cumulative risk factors are at risk for short sleep duration. Further research is needed to uncover biological mechanisms underlying multiple sleep parameters across developmental ages. Support (if any):

Comparative analysis of sleep patterns and attention components in high school and college adolescents.

Adolescence is a phase with physiological and behavioral changes. One of them occurs in the sleep-wake cycle pattern, manifested by a phase delay. However, morning school start time can decrease sleep duration during weekdays, impairing adolescent cognitive performance and well-being. Adolescents of different ages and educational level might suffer the impact of academic demand on sleep-wake cycle and cognition differently. Thus, the aim of this study is to compare the sleep habits and quality, sleepiness upon awakening and attention components among adolescents in the first years of high school and college. 71 adolescents participated in the study (45 girls and 26 boys), 44 enrolled in high school morning classes (G1 - 15.5±0.7 years), from a private school, and 27 college students enrolled in morning classes (G2 - 18.8±1.04 years), from biosciences courses from a public institution. The groups did not differ in bedtime, get up time, time in bed and sleep irregularity. However, both groups showed differences according to the day of the week, bedtime and get up time became later and time in bed extended on weekends. G1 presented worse sleep quality and regarding attention, showed higher percentage of omissions in all components and worse performance in sustained attention (ANOVA, p<0.05). The poorer sleep quality of high school adolescents and reduced attention may have a negative effect on school performance. Additional studies are needed to investigate the causes of these differences between these two educational levels.