Postpartum sleep health in a multiethnic cohort of women during the COVID-19 pandemic in New York City.

OBJECTIVE/DESIGN: Cross-sectional study to examine the determinants of sleep health among postpartum women during the COVID-19 pandemic in New York City (NYC). SETTING/PARTICIPANTS: A subset of participants recruited as part of the COVID-19 Mother Baby Outcomes (COMBO) cohort at Columbia University (N = 62 non-Hispanic White, N = 17 African American, N = 107 Hispanic). MEASUREMENTS: Data on maternal sleep, COVID-19 infection during pregnancy, sociodemographic, behavioral, and psychological factors were collected via questionnaire at 4 months postpartum. Self-reported subjective sleep quality, latency, duration, efficiency, disturbances, and daytime dysfunction were examined as categorical variables (Pittsburgh Sleep Quality Index [PSQI]). Associations between sleep variables and COVID-19 status, time of the pandemic, sociodemographic, behavioral, and psychological factors were estimated via independent multivariable regressions. RESULTS: Mothers who delivered between May-December 2020, who delivered after the NYC COVID-19 peak, experienced worse sleep latency, disturbances and global sleep health compared to those who delivered March-April 2020, the peak of the pandemic. Maternal depression, stress and COVID-19-related post-traumatic stress were associated with all sleep domains except for sleep efficiency. Maternal perception of infant's sleep as a problem was associated with worse global PSQI score, subjective sleep quality, duration, and efficiency. Compared to non-Hispanic White, Hispanic mothers reported worse global PSQI scores, sleep latency, duration and efficiency, but less daytime dysfunction. CONCLUSIONS: These findings provide crucial information about sociodemographic, behavioral, and psychological factors contributing to sleep health in the postpartum period.

Effects of Chinese herbal medicines on dementia risk in patients with sleep disorders in Taiwan.

ETHNOPHARMACOLOGICAL RELEVANCE: Sleep disorders affect an estimated 150 million people worldwide and result in adverse health, safety, and work performance-related outcomes that have important economic consequences. In Taiwan, Chinese herbal medicine (CHM) is a complementary natural medicine and has been widely used as an adjunctive therapy. AIM OF THE STUDY: This study aimed to investigate the effect of CHM on dementia risk in patients with sleep disorders in Taiwan. MATERIALS AND METHODS: We identified 124,605 patients with sleep disorders between the ages of 20 and 60 years. Of these, 5876 CHM users and 5876 non-CHM users were matched according to age and gender. The chi-squared test, Cox proportional hazard model, Kaplan-Meier method, and log-rank test were used for the comparisons. Association rule mining and network analysis were applied to determine a CHM pattern specialized for sleep disorders. RESULTS: More CHM users did not use sleeping pills than non-CHM users. CHM users had a lower risk of dementia than non-CHM users after adjusting for age, gender, and sleeping pill use (hazard ratio (HR): 0.469, 95% CI = 0.289-0.760; p-value = 0.002). The cumulative incidence of dementia was lower among CHM users (long-rank test, p-value < 0.001). Association rule mining and network analysis showed that Ye-Jiao-Teng (YJT; Caulis Polygoni Multiflori; Polygonum multiflorum Thunb), Suan-Zao-Ren-Tang (SZRT), Jia-Wei-Xiao-Yao-San (JWXYS), He-Huan-Pi (HHP; Cortex Albizziae; Albizia julibrissin Durazz.), and Suan-Zao-Ren (SZR; Semen Zizyphi Spinosae; Ziziphus jujuba Mill.) were important CHMs for patients with sleep disorders in Taiwan. CONCLUSIONS: A comprehensive list of herbal medicines may be useful for the clinical treatment of patients with sleep disorders, and for future scientific investigations into the prevention of dementia in these patients.

Fragmented sinoatrial dynamics in the prediction of atrial fibrillation: the Multi-Ethnic Study of Atherosclerosis.

Heart rate fragmentation (HRF), a marker of abnormal sinoatrial dynamics, was shown to be associated with incident cardiovascular events in the Multi-Ethnic Study of Atherosclerosis (MESA). Here, we test the hypothesis that HRF is also associated with incident atrial fibrillation (AF) in the MESA cohort of participants who underwent in-home polysomnography (PSG) and in two high-risk subgroups: those ≥70 yr taking antihypertensive medication and those with serum concentrations of NH2-terminal prohormone B-type natriuretic peptide (NT-proBNP) >125 pg/ml (top quartile). Heart rate time series (n = 1,858) derived from the ECG channel of the PSG were analyzed using newly developed HRF metrics, traditional heart rate variability (HRV) indices and two widely used nonlinear measures. Eighty-three participants developed AF over a mean follow-up period of 3.83 ± 0.87 yr. A one-standard deviation increase in HRF was associated with a 31% (95% CI: 3-66%) increase in risk of incident AF, in Cox models adjusted for age, height, NT-proBNP, and frequent premature supraventricular complexes. Furthermore, HRF added value to the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE)-AF models. Traditional HRV and nonlinear indices were not significantly associated with incident AF. In the two high-risk subgroups defined above, HRF was also significantly associated with incident AF in unadjusted and adjusted models. These findings support the translational utility of HRF metrics for short-term (∼4-yr) prediction of AF. In addition, they support broadening the concept of atrial remodeling to include electrodynamical remodeling, a term used to refer to pathophysiological alterations in sinus interbeat interval dynamics.NEW & NOTEWORTHY This study is the first demonstration that heart rate fragmentation (HRF), a marker of anomalous sinoatrial dynamics, is an independent predictor of atrial fibrillation (AF). Traditional measures of heart rate variability and two widely used nonlinear measures were not associated with incident AF in the Multi-Ethnic Study of Atherosclerosis. Fragmentation measures added value to the strongest contemporary predictors of AF, including ECG-derived parameters, coronary calcification score, serum concentrations of NH2-terminal prohormone B-type natriuretic peptide, and supraventricular ectopy. The computational algorithms for quantification of HRF could be readily incorporated into wearable ECG monitoring devices.

Evidence Base Update on Assessing Sleep in Youth.

BACKGROUND: Sleep is vital to youth well-being and when it becomes disturbed - whether due to environmental or individual factors - mental and physical health suffer. Sleep problems can also be a symptom of underlying mental health disorders. Assessing different components of sleep, including quality and hygiene, can be useful both for identifying mental health problems and for measuring changes in well-being over time. However, there are dozens of sleep-related measures for youth and it can be difficult to determine which to select for a specific research or clinical purpose. The goal of this review was to identify sleep-related measures for clinical and/or research use in youth mental health settings, and to update the evidence base on this topic. METHOD: We generated a list of candidate measures based on other reviews and searched in PubMed and PsycINFO using the terms "sleep" AND (measure OR assessment OR questionnaire) AND (psychometric OR reliability OR validity). Search results were limited to studies about children and adolescents (aged 2-17) published in English. Additional criteria for inclusion were that there had to be at least three publications reporting on the measure psychometrics in community or mental health populations. Sleep measures meeting these criteria were evaluated using the criteria set by De Los Reyes and Langer (2018). RESULTS: Twenty-six measures, across four domains of sleep - insomnia, sleep hygiene, sleepiness, sleep quality - met inclusion criteria. Each measure had at least adequate clinical utility. No measure(s) emerged as superior across psychometric domains. CONCLUSION: Clinicians and researchers must evaluate sleep measures for each use case, as the intended purpose will dictate which measure is best. Future research is necessary to evaluate measure performance in transdiagnostic mental health populations, including youth with serious mental illness.

Chronic Severe Sleep Problems among Non-Nordic Immigrants. Data from a Population Postal Survey in Mid-Sweden.

Sweden has a large population of both recent and established immigrants with high prevalence of risk factors for ill health. Here, we aimed to explore the prevalence of chronic severe sleep problems (CSSP) among non-Nordic-born persons, and to evaluate the risk for CSSP when fully adjusted for covariates. Our additional hypothesis was that lengthier time since immigration would reduce the risk for CSSP. We used data from a large-population postal survey covering life and health issues among inhabitants in mid-Sweden. Relationship between different countries of birth and CSSP was assessed in logistic analyses for more severe and longstanding pain, sex, employment, mental disability, gastrointestinal problems, and length of stay (short, middle time, and up to ten years of stay). Persons of non-Nordic birth reported significantly more often CSSP, regardless of short or long-term stay. Our findings indicate that non-Nordic birth, regardless of residence time and covariates, was an independent and significant predictor for CSSP. The findings may contribute to increasing awareness in healthcare personnel to recognize chronic sleep problems among immigrant patients. Thus, our study might contribute to developing strategies to enhance health for minorities.

Acculturation Associated with Sleep Duration, Sleep Quality, and Sleep Disorders at the US-Mexico Border.

Sleep disparities exist among Hispanics/Latinos, although little work has characterized individuals at the United States (US)-Mexico border, particularly as it relates to acculturation. This study examined the association of Anglo and Mexican acculturation to various facets of sleep health among those of Mexican descent at the US-Mexico border. Data were collected from N = 100 adults of Mexican descent in the city of Nogales, Arizona (AZ). Surveys were presented in English or Spanish. Acculturation was assessed with the Acculturation Scale for Mexican-Americans (ARSMA-II). Insomnia was assessed with the Insomnia Severity Index (ISI), sleepiness was assessed with the Epworth Sleepiness Scale (ESS), sleep apnea risk was assessed with the Multivariable Apnea Prediction (MAP) index, weekday and weekend sleep duration and efficiency were assessed with the Sleep Timing Questionnaire, sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI), and sleep duration and sleep medication use were assessed with PSQI items. No associations were found between Mexican acculturation and any sleep outcomes in adjusted analyses. Anglo acculturation was associated with less weekend sleep duration and efficiency, worse insomnia severity and sleep quality, and more sleep apnea risk and sleep medication use. These results support the idea that sleep disparities may depend on the degree of acculturation, which should be considered in risk screening and interventions.

Insight into the relationship between sleep characteristics and anxiety: A cross-sectional study in indigenous and minority populations in northeastern Greece.

A cross-sectional population-based study was conducted in order to evaluate the association of sleep characteristics with anxiety disorders using self-reported questionnaires and taking into account several socio-demographic, lifestyle and health related characteristics. 957 participants between 19 and 86 years old were enrolled in our study. Anxiety symptoms were assessed using the Zung Self-rating Anxiety Scale. Participants self-reported their daily sleep habits and filled in the following scales: Epworth Sleepiness Scale, Athens Insomnia Scale, Pittsburgh Sleep Quality Index and Berlin Questionnaire. Overall prevalence of anxiety was 33.6%. Anxiety symptoms were more prominent among minority groups. Subjects with anxiety reported shorter sleep duration and reduced sleep efficiency. After adjusting for all possible confounders, they were five times more likely to exhibit short sleep duration (≤6h) and 0.60 times less likely long sleep duration (>8h). These relations remained significant in both genders, but were more pronounced among men. Moreover, anxiety was associated with excessive daytime sleepiness, insomnia, poor sleep quality and higher risk of obstructive sleep apnea (OSA). Results highlight the association of sleep disturbances with anxiety disorders and call for conduction of larger scale prospective studies in order to assess causality on the clinically important relationship between sleep characteristics and anxiety disorders.

Racial disparities in sleep disturbances among patients with and without coronary artery disease: The role of clinical and socioeconomic factors.

OBJECTIVE: To investigate differences in sleep quality by race in participants with and without a prior myocardial infarction (MI). DESIGN: Case-control study. SETTING: Emory-affiliated hospitals in Atlanta, Georgia. PARTICIPANTS: Two hundred seventy-three individuals (190 Black) ≤60 years of age with a verified MI in the previous 8 months, and 100 community controls (44 Black) without a history of MI. MEASUREMENTS: Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). Psychological factors were assessed using standardized questionnaires and clinical risk factors through medical history and chart review. RESULTS: A significant interaction existed between race and MI status on sleep quality (P= .01), such that Black individuals with a history of MI, but not controls, reported worse sleep quality than their non-Black counterparts. Among MI cases, being Black was independently associated with higher PSQI scores after adjusting for baseline demographics (B = 2.17, 95% confidence interval 1.17, 3.17, P = .006). Clinical risk factors, psychological factors and socioeconomic status (household income and years of education) all contributed equally to explain race-related disparities in sleep among MI cases. After further adjustment for these factors, the association was attenuated and no longer significant (B = 0.70, 95% confidence interval = -0.10, 1.21, P = .26). CONCLUSION: Black post-MI patients, but not healthy controls, have significantly poorer sleep quality than non-Blacks. This difference is driven by a combination of factors, including clinical risk factors, psychological factors as well as adverse socioeconomic conditions among Black individuals with MI.

Racial/Ethnic Differences in Sleep Quality among Older Adults: Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) Study.

Background: We assessed cross-sectional differences in sleep quality and risk factors among Asian, Black, Latino, and White participants in the Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) Study. Methods: KHANDLE enrolled community-dwelling adults aged ≥65 years living in northern California. Participants completed a modified Pittsburgh Sleep Quality Index to measure six sleep components and a global sleep score (scored 0-24). Covariates included age, sex, central adiposity, education, income, alcohol consumption, ever smoking, physical activity, and depression. Ordinal logistic regression was used to model sleep component scores across race/ethnic groups. Linear regression was used to assess racial/ethnic differences in global sleep score and the association between risk factors and global sleep score. Results: 1,664 participants with a mean age of 76 (SD=7) and mean global sleep score of 6 (SD=4) were analyzed. Using Latinos as reference (highest average sleep score), Blacks had an average .96 (.37, 1.54) unit higher global sleep score (worse sleep) while Asians [ß: .04 (-.56, .63)] and Whites [ß: .28 (-.29, .84)] did not significantly differ. Compared with Latinos, Blacks and Asians had greater odds of a worse score on the sleep duration component; Blacks and Whites had greater odds of a worse score on the sleep disturbances component; and, Whites had greater odds of a worse score on the medication component. Risk factors for poor sleep did not differ by race/ethnicity except alcohol consumption (interaction P=.04), which was associated with poor sleep in Blacks only. Conclusions: In this cohort, racial/ethnic differences in sleep quality were common.

Mental health and sleep disparities in an urban college sample: A longitudinal examination of White and Black students.

OBJECTIVE: Racial disparities in sleep may be consequential among college students given high rates of dysfunctional sleep among this population. The present study sought to investigate whether disparities in sleep explain existing mental health disparities. METHOD: Data included secondary analysis of a college risk behaviors and health study (n = 1242, mean age = 18.5). Race was dichotomized as White or Black, excluding all others, with participants completing measures of sleep at baseline and measures of depression and anxiety at follow-up 1 to 2 years later. RESULTS: Compared to White students, Black students were more likely to report lower rates of depression and anxiety, but poorer sleep outcomes. Mediation analyses revealed that sleep partially mediated (suppressed) the association between race and depressive and anxiety symptoms. CONCLUSIONS: Results indicate that disparities in sleep may play an important role in the association between race and mental health symptoms among college students. Future health disparity research would benefit from exploring the potentially bidirectional relationship between sleep and mental health symptoms among college students.

Self-reported sleep problems and their relationship to life and living of Maori and non-Maori in advanced age.

OBJECTIVE: Life expectancy is increasing. Sleep problems are more likely with advancing age however, are largely overlooked, and the longitudinal health impact of reported sleep problems is unclear. In this study, relationships were examined between reporting prior or current sleep problems with health outcomes, among Maori and non-Maori of advanced age. METHOD: Data were available from 251 Maori and 398 non-Maori adults (79-90 years) from Wave 1 (W1) of Te Puawaitanga o Nga Tapuwae Kia Ora Tonu. Life and Living in Advanced Age: A Cohort Study in NZ (LiLACS NZ). Four years later (W5), data were available from 85 Maori and 200 non-Maori participants. Relationships between reporting problem sleep at W1 and cohort and health outcomes at W5 were investigated using generalised linear models and Cox proportional hazards models. RESULTS: Over 25% reported sleep problems at both waves. Mortality was associated with problem sleep for Maori but not non-Maori. Within the whole group, W1 problem sleepers were more likely to still have problems at W5, compared with nonproblem sleepers at W1. They also had poorer indicators of physical health and pain at W5. Problem sleepers at W5 had poorer concurrent mental health and increased likelihood of hospital admittance in the last year. CONCLUSION: Sleep health is an important characteristic of ageing well, particularly for Maori. Early recognition and management of sleep problems could improve physical and mental health with advancing age.

Monthly variation of hot flashes, night sweats, and trouble sleeping: effect of season and proximity to the final menstrual period (FMP) in the SWAN Menstrual Calendar substudy.

OBJECTIVE: Although reproductive function is influenced by season, few studies have evaluated seasonal effects on menopausal symptoms. We assessed the impact of season and proximity to the final menstrual period (FMP) on frequency of symptom reporting. METHODS: In all, 955 participants in the Study of Women's Health Across the Nation recorded whether or not they had experienced menopausal symptoms on a monthly menstrual calendar over a 10-year period. We modeled the log-odds of presence of a given symptom each month using a logistic mixed-effects model, assuming a third-order polynomial before the FMP and a different third-order polynomial after the FMP. We assumed sine and cosine functions for month of the year. RESULTS: Five to 10 years before the FMP, ∼20% of women reported hot flashes and night sweats, whereas ∼40% reported trouble sleeping. Prevalence rose ∼4 years before the FMP with a sharp jump in hot flash (∼60%) and night sweats (∼40%) prevalence coincident with the FMP. Peaks in hot flashes and trouble sleeping were observed in July with troughs in January. The peak and trough in night sweats occurred about 1 month earlier. Odds of hot flashes, night sweats, and trouble sleeping were 66%, 50%, and 24% greater, respectively, at the seasonal peak versus the seasonal minimum. CONCLUSION: Menopausal symptoms exhibit seasonal variation associated with the summer and winter equinoxes. Seasonal increases in night sweats precede increases in hot flashes. Prospectively recorded monthly symptom data demonstrate that hot flashes and night sweats increase notably coincident with the FMP. : Video Summary:http://links.lww.com/MENO/A476.

The Association Between Self-perceived Health and Sleep-Quality and Anxiety Among Newly Arrived Refugees in Sweden: A Quantitative Study.

Previous research findings suggest that insomnia could be related to decreased health status and that it could also be affected by traumatic life experiences, such as war. Good health is important for newly arrived refugees for an effective integration process. The aim of the present study is, therefore, to investigate the association between self-perceived health and sleep quality among newly arrived refugees in Sweden. The results are based on 681 migrants who participated in a survey between 2015 and 2016. There was a significant odds ratio (OR) after adjustment for confounders for newly arrived refugees that were experiencing bad self-perceived health to also experience bad sleep: OR 8.07 (4.34-15.00). Furthermore, the OR remained significant but lower after adjustments for confounders for newly arrived refugees that had bad self-perceived health to be suffering from anxiety during sleep, with OR 3.83 (2.11-6.94).

Racial Disparities in Sleep: Associations With Discrimination Among Ethnic/Racial Minority Adolescents.

This study investigates the same-day associations between discrimination and sleep among 350 adolescents ages 13-15 (M = 14.29, SD = 0.65; Asian = 41%, Black = 22%, Latinx = 37%). Assessing sleep duration, sleep onset latency, and wake minutes after sleep onset using wrist actigraphy, Black adolescents slept 35 min less than Asian and 36 min less than Latinx youth. Black adolescents suffered the most wake minutes after sleep onset, followed by Latinx and Asian youth. Latinx youth reported the highest levels of sleep disturbance, whereas Asian youth reported the highest levels of daytime dysfunction. Daily discrimination was associated with lower levels of same-night sleep onset latency, more sleep disturbance, more next-day daytime dysfunction, and higher next-day daytime sleepiness.

Discrimination and Sleep Mediate Ethnic/Racial Identity and Adolescent Adjustment: Uncovering Change Processes With Slope-as-Mediator Mediation.

This study employs slope-as-mediator techniques to explore how the daily association between ethnic/racial discrimination and sleep disturbances serves as an intermediary link between ethnic/racial identity (ERI) and psychological adjustment. In a diverse sample of 264 adolescents (Mage  = 14.3 years old, 70% female, 76% United States born, 25% African American, 32% Asian American, 43% Latinx), discrimination was associated with sleep disturbance. Furthermore, ERI commitment buffered the impact of discrimination on sleep, whereas ERI exploration exacerbated the impact of discrimination. Finally, the daily level association between discrimination and sleep (i.e., daily slope) mediated the association between ERI and adolescent adjustment. Substantive links between discrimination and sleep are discussed as well as broader applications of slope-as-mediator techniques.

Diversity in pediatric behavioral sleep intervention studies.

Studies designed to assess the efficacy of behavioral sleep interventions for infants and young children often report sleep improvements, but the generalization to children and families of diverse backgrounds is rarely assessed. The present study describes a systematic review of the racial, ethnic, and socioeconomic diversity of behavioral sleep intervention studies for young children. Thirty-two behavioral sleep intervention studies (5474 children) were identified using PRISMA guidelines. Each study was coded for racial and ethnic composition, parental educational attainment (an index of socioeconomic resources), and country of origin. Racial or ethnic information was obtained for 19 studies (60%). Study participants were primarily White and from predominantly White countries. Overall, 21 (66%) of the included studies provided information on parental education. Most of these studies had samples with moderate to high educational attainment. Behavioral sleep intervention studies to date include samples with insufficient diversity. Overall, this study highlights a critical gap in pediatric sleep intervention research and supports a call to further include families from diverse backgrounds when assessing behavioral sleep interventions.

[Ethnic features of sleep disorders in climacteric women]. / Étnicheskie osobennosti narushenii sna u zhenshchin klimaktericheskogo perioda.

AIM: To evaluate the features of sleep disorders in Caucasian and Asian menopausal women. MATERIAL AND METHODS: Five hundreds and forty-two menopausal women, aged 45 to 60 years, were divided into Caucasians (Russians (n=342)) and Asians (Buryats (n=200)). All women were examined by an obstetrician-gynecologist. Also, a general clinical examination and an analysis of medical documentation were conducted. Diagnoses of insomnia and obstructive sleep apnea syndrome (OSAS) were made according to the results of specialized somnological questionnaires and polysomnographic monitoring. RESULTS: The frequency of sleep disorders in Caucasian women in perimenopause was 61.2%, in postmenopause 65.5%; in Asian women it was 63.5% in perimenopause, 72.9% in postmenopause. Difficulties in falling asleep (69.4%) and difficulties in morning awakenings (63.5%) were found in perimenopausal Caucasian women and frequent nightly awakenings (83.5%) and OSAS (48.9%) were found in postmenopausal ones. There were no differences in the structure of sleep disorders depending on the menopause phase in Asian women. The most common complaints were frequent nighttime awakenings (69.5% in perimenopause, 76.9% in postmenopause). Ethnic differences in the sleep complaints were found only in the perimenopause. The decrease in sleep efficacy and changes in the rapid eye movement sleep were found in Asian women as compared to Caucasians. Moreover, apnea-hypopnea index was higher and oxygen saturation was lower in Asian women compared to Caucasians. CONCLUSION: The formation of sleep disorders in menopausal women has ethnogenetic features.

Epigenome-wide association analysis of daytime sleepiness in the Multi-Ethnic Study of Atherosclerosis reveals African-American-specific associations.

STUDY OBJECTIVES: Daytime sleepiness is a consequence of inadequate sleep, sleep-wake control disorder, or other medical conditions. Population variability in prevalence of daytime sleepiness is likely due to genetic and biological factors as well as social and environmental influences. DNA methylation (DNAm) potentially influences multiple health outcomes. Here, we explored the association between DNAm and daytime sleepiness quantified by the Epworth Sleepiness Scale (ESS). METHODS: We performed multi-ethnic and ethnic-specific epigenome-wide association studies for DNAm and ESS in the Multi-Ethnic Study of Atherosclerosis (MESA; n = 619) and the Cardiovascular Health Study (n = 483), with cross-study replication and meta-analysis. Genetic variants near ESS-associated DNAm were analyzed for methylation quantitative trait loci and followed with replication of genotype-sleepiness associations in the UK Biobank. RESULTS: In MESA only, we detected four DNAm-ESS associations: one across all race/ethnic groups; three in African-Americans (AA) only. Two of the MESA AA associations, in genes KCTD5 and RXRA, nominally replicated in CHS (p-value < 0.05). In the AA meta-analysis, we detected 14 DNAm-ESS associations (FDR q-value < 0.05, top association p-value = 4.26 × 10-8). Three DNAm sites mapped to genes (CPLX3, GFAP, and C7orf50) with biological relevance. We also found evidence for associations with DNAm sites in RAI1, a gene associated with sleep and circadian phenotypes. UK Biobank follow-up analyses detected SNPs in RAI1, RXRA, and CPLX3 with nominal sleepiness associations. CONCLUSIONS: We identified methylation sites in multiple genes possibly implicated in daytime sleepiness. Most significant DNAm-ESS associations were specific to AA. Future work is needed to identify mechanisms driving ancestry-specific methylation effects.

Delayed Sleep Time in African Americans and Depression in a Community-Based Population.

STUDY OBJECTIVES: Studies have shown racial differences in circadian rhythm in African Americans when compared to non-Hispanic whites, and an association between circadian dyssynchrony and depression. We hypothesized that the prevalence of delayed sleep time is greater in African Americans when compared to whites and that delayed sleep time is associated with depression. METHODS: We analyzed data from the Sleep Heart Health Study (SHHS), a large community-based sample. Delayed sleep time was defined as self-reported weeknight bedtime after midnight. Depression was defined based on participant's response to the question, "In the past 4 weeks have you felt downhearted and blue?" or reported antidepressant use. We performed multivariate linear and logistic regression, adjusting for age, sex, race, body mass index, smoking, apnea-hypopnea index, alcohol use, and caffeine consumption. RESULTS: Adjusted weekday bedtime was 15 ± 7 minutes later in African Americans compared to whites (P < .001). Similarly, weekend bedtime was 18 ± 7 minutes later in African Americans compared to whites (P = .025). The prevalence of delayed sleep time was greater in African Americans (33.3%) compared to whites (18.7%; P < .001). After adjusting for confounders, when compared to whites, a greater proportion of African Americans had delayed sleep time (adjusted odds ratio [aOR] 2.03; 95% confidence interval [95% CI] 1.5, 2.4; P < .0001). Depression was independently associated with delayed sleep time after adjustment (aOR 1.4; 95% CI 1.1, 1.7; P = .007). CONCLUSIONS: African Americans are more likely to have a delayed sleep time compared to whites, and delayed sleep time was independently associated with depression.