A pilot prospective study of sleep patterns and DNA methylation-characterized epigenetic aging in young adults

The association between sleep quality and accelerated epigenetic aging with metabolic syndrome in Korean adults

BACKGROUND

Healthy sleep is vital for maintaining optimal mental and physical health. Accumulating evidence suggests that sleep loss and disturbances play a significant role in the biological aging process, early onset of disease, and reduced lifespan. While numerous studies have explored the association between biological aging and its drivers, only a few studies have examined its relationship with sleep quality. In this study, we investigated the associations between sleep quality and epigenetic age acceleration using whole blood samples from a cohort of 692 Korean adults. Sleep quality of each participant was assessed using the validated Pittsburgh Sleep Quality Index (PSQI), which encompassed seven domains: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbance, use of sleep medication, and daytime dysfunction. Four epigenetic age accelerations (HorvathAgeAccel, HannumAgeAccel, PhenoAgeAccel, and GrimAgeAccel) and the pace of aging, DunedinPACE, were investigated for epigenetic aging estimates.

RESULTS

Among the 692 participants (good sleepers [n = 441, 63.7%]; poor sleepers [n = 251, 36.3%]), DunedinPACE was positively correlated with PSQI scores in poor sleepers ( γ =0.18, p < 0.01). GrimAgeAccel ( β =0.18, p = 0.02) and DunedinPACE ( β =0.01, p < 0.01) showed a statistically significant association with PSQI scores only in poor sleepers by multiple linear regression. In addition, every one-point increase in PSQI was associated with a 15% increase in the risk of metabolic syndrome (MetS) among poor sleepers (OR = 1.15, 95% CI = 1.03-1.29, p = 0.011). In MetS components, a positive correlation was observed between PSQI score and fasting glucose ( γ = 0.19, p < 0.01).

CONCLUSIONS

This study suggests that worsening sleep quality, especially in poor sleepers, is associated with accelerated epigenetic aging for GrimAgeAccel and DundinePACE with risk of metabolic syndrome. This finding could potentially serve as a promising strategy for preventing age-related diseases in the future.

Does sleep link child maltreatment to depressive symptoms among incoming first-year college students?

Study Objectives

We examined whether sleep (i.e. quality, regularity, and duration) mediated associations between child maltreatment (CM) and depressive symptoms among emerging adults undergoing the major life transition of starting college.

Methods

Students (N = 1400; 44% male; 48% non-Hispanic white, 20% non-Hispanic Asian, 15% Hispanic all races, 7% non-Hispanic black, and 10% non-Hispanic other races) completed daily sleep diaries for 9 weeks, followed by the Childhood Trauma Questionnaire-Short Form, Pittsburgh Sleep Quality Index, and the Center for Epidemiologic Studies Depression Scale (CES-D). DSD data were used to compute participants' Sleep Regularity Index and average 24-hour total sleep time. We used a nonparametric structural equation modeling bootstrap approach and full information maximum likelihood to account for missing data. In model 1, we controlled for sex and race and ethnicity. In model 2, we further adjusted for baseline CES-D scores.

Results

The prevalence of self-reported moderate-to-severe CM was 22%. Small but significant indirect effects of CM on greater depressive symptoms through worse sleep quality (β = 0.06, 95% CI = 0.04, 0.09) and lower sleep regularity (β = 0.02, 95% CI = 0.005, 0.03) were observed in model 1. In model 2, only the indirect effect of sleep quality remained significant (β = 0.03, 95% CI = 0.01, 0.06).

Conclusions

Poorer sleep quality may partially account for associations between CM and depressive symptoms during the first semester of college. Including sleep as a target in student health interventions on college campuses may not only help buffer against poor mental health outcomes for students with CM, but also poor academic and socioeconomic outcomes long-term.

Short Sleep and Insomnia Are Associated With Accelerated Epigenetic Age

OBJECTIVE

Short sleep and insomnia are each associated with a greater risk of age-related disease, which suggests that insufficient sleep may accelerate biological aging. We examine whether short sleep and insomnia alone or together relates to epigenetic age among older adults.

METHODS

A total of 3795 men (46.3%) and women aged 56 to 100 years from the Health and Retirement Study were included. Insomnia was defined as reporting at least one insomnia symptom (difficulty falling asleep, waking up at night, or waking up too early in the morning) and feeling unrested when waking up most of the time. Those reporting <6 hours of bedtime were categorized as short sleepers. Three second- or third-generation epigenetic age acceleration clocks were derived from the 2016 Health and Retirement Study Venous Blood Study. The linear regression analysis was adjusted for age, sex, race/ethnicity, education, and obesity status.

RESULTS

Insomnia and short sleep were associated with acceleration of GrimAge of 0.49 (95% confidence interval [CI] = 0.03-0.94 years; p = .04) and 1.29 (95% CI = 0.52-2.07 years; p = .002) years, respectively, as well as a faster pace of aging (DunedinPACE; 0.018 [95% CI = 0.004-0.033; p = .02] and 0.022 [95% CI = -0.004 to 0.048; p = .11]). Compared with healthy sleepers, individuals with the combination of short sleep and insomnia had an accelerated GrimAge (0.97 years; 95% CI = 0.07-1.87 years, p = .04) and a greater DunedinPACE (0.032; 95% CI = 0.003-0.060, p = .04).

CONCLUSIONS

Our findings indicate that short sleep, insomnia, and the combination of the two are linked to epigenetic age acceleration, suggesting that these individuals have an older biological age that may contribute to risk of comorbidity and mortality.

Epigenetic Aging Associations With Psychoneurological Symptoms and Social Functioning in Adults With Sickle Cell Disease

Objective: Sickle cell disease (SCD), the most common inherited blood disorder in the United States, is associated with severe psychoneurological symptoms. While epigenetic age acceleration has been linked to psychoneurological symptom burden in other diseases, this connection is unexplored in SCD. This study aimed to assess the association between epigenetic age acceleration and psychoneurological symptom burden in SCD. Methods: In this cross-sectional study, emotional impact, pain impact, sleep impact, social functioning, and cognitive function were assessed in 87 adults living with SCD. DNA methylation data were generated from blood specimens and used to calculate epigenetic age using five clocks (Horvath, Hannum, PhenoAge, GrimAge, & DunedinPACE). Associations between epigenetic age acceleration and symptoms were assessed. Results: The sample (N = 87) had a mean (SD) chronologic age was 30.6 (8.1) years. Epigenetic age acceleration was associated with several symptom outcomes. GrimAge age acceleration (β = -0.49, p = .03) and increased DunedinPACE (β = -2.23, p = .004) were associated with worse emotional impact scores. PhenoAge (β = -0.32, p = .04) and the GrimAge (β = -0.48, p = .05) age acceleration were associated with worse pain impact scores. Increased DunedinPACE (β = -2.07 p = .04) were associated with worse sleep impact scores. Increased DunedinPACE (β = -2.87, p = .005) was associated with worse social functioning scores. We did not find associations between epigenetic age acceleration and cognitive function in this sample. Conclusion: Epigenetic age acceleration was associated with worse symptom experiences, suggesting the potential for epigenetic age acceleration as a biomarker to aid in risk stratification or targets for intervention to mitigate symptom burden in SCD.

The race-based stress reduction intervention (RiSE) study on African American women in NYC and Chicago: Design and methods for complex genomic analysis

RiSE study aims to evaluate a race-based stress-reduction intervention as an effective strategy to improve coping and decrease stress-related symptoms, inflammatory burden, and modify DNA methylation of stress response-related genes in older AA women. This article will describe genomic analytic methods to be utilized in this longitudinal, randomized clinical trial of older adult AA women in Chicago and NYC that examines the effect of the RiSE intervention on DNAm pre- and post-intervention, and its overall influence on inflammatory burden. Salivary DNAm will be measured at baseline and 6 months following the intervention, using the Oragene-DNA kit. Measures of perceived stress, depressive symptoms, fatigue, sleep, inflammatory burden, and coping strategies will be assessed at 4 time points including at baseline, 4 weeks, 8 weeks, and 6 months. Genomic data analysis will include the use of pre-processed and quality-controlled methylation data expressed as beta (β) values. Association analyses will be performed to detect differentially methylated sites on the targeted candidate genes between the intervention and non-intervention groups using the Δβ (changes in methylation) with adjustment for age, health behaviors, early life adversity, hybridization batch, and top principal components of the probes as covariates. To account for multiple testing, we will use FDR adjustment with a corrected p-value of <0.05 regarded as statistically significant. To assess the relationship between inflammatory burden and Δβ among the study samples, we will repeat association analyses with the inclusion of individual inflammation protein measures. ANCOVA will be used because it is more statistically powerful to detect differences.

Association between sleep traits and biological aging risk: a Mendelian randomization study based on 157 227 cases and 179 332 controls

STUDY OBJECTIVES

To investigate whether sleep traits are associated with the risk of biological aging using a case-control design with Mendelian randomization (MR) analyses.

METHODS

We studied 336 559 participants in the UK Biobank cohort, including 157 227 cases of accelerated biological aging and 179 332 controls. PhenoAge, derived from clinical traits, estimated biological ages, and the discrepancies from chronological age were defined as age accelerations (PhenoAgeAccel). Sleep behaviors were assessed with a standardized questionnaire. propensity score matching matched control participants to age-accelerated participants, and a conditional multivariable logistic regression model estimated odds ratio (OR) and 95% confidence intervals (95% CI). Causal relationships between sleep traits and PhenoAgeAccel were explored using linear and nonlinear MR methods.

RESULTS

A U-shaped association was found between sleep duration and PhenoAgeAccel risk. Short sleepers had a 7% higher risk (OR = 1.07; 95% CI: 1.03 to 1.11), while long sleepers had an 18% higher risk (OR = 1.18; 95% CI: 1.15 to 1.22), compared to normal sleepers (6-8 hours/day). Evening chronotype was linked to higher PhenoAgeAccel risk than morning chronotype (OR = 1.14; 95% CI: 1.10 to 1.18), while no significant associations were found for insomnia or snoring. Morning chronotype had a protective effect on PhenoAgeAccel risk (OR = 0.87, 95% CI: 0.79 to 0.95) per linear MR analysis. Genetically predicted sleep duration showed a U-shaped relationship with PhenoAgeAccel, suggesting a nonlinear association (pnonlinear < 0.001).

CONCLUSIONS

The study suggests that improving sleep can slow biological aging, highlighting the importance of optimizing sleep as an intervention to mitigate aging's adverse effects.

Sleep Duration Polygenic Risk and Phenotype: Associations with Biomarkers of Accelerated Aging in the Baltimore Longitudinal Study of Aging

We sought to explore whether genetic risk for, and self-reported, short sleep are associated with biological aging and whether age and sex moderate these associations. Participants were a subset of individuals from the Baltimore Longitudinal Study of Aging who had complete data on self-reported sleep (n = 567) or genotype (n = 367). Outcomes included: Intrinsic Horvath age, Hannum age, PhenoAge, GrimAge, and DNAm-based estimates of plasminogen activator inhibitor-1 (PAI-1) and granulocyte count. Results demonstrated that polygenic risk for short sleep was positively associated with granulocyte count; compared to those reporting <6 hr sleep, those reporting >7 hr demonstrated faster PhenoAge and GrimAge acceleration and higher estimated PAI-1. Polygenic risk for short sleep and self-reported sleep duration interacted with age and sex in their associations with some of the outcomes. Findings highlight that polygenic risk for short sleep and self-reported long sleep is associated with variation in the epigenetic landscape and subsequently aging.

Association of sleep duration, chronotype, social jetlag, and sleep disturbance with phenotypic age acceleration: A cross-sectional analysis

OBJECTIVE

Sleep is a critical health-related behavior; research evidence has shown that sleep duration, poor sleep quality and insomnia are associated with aging and relevant age-related diseases. However, the associations between sleep duration, chronotype, sleep disturbance, and biological age have not been comprehensively assessed. This study aimed to examine sleep characteristics with biological age.

METHODS

The study included 6534 participants aged 20 years and older from the National Health and Nutrition Examination Survey between 2017 and March 2020. Sleep questionnaires were used to collect information on sleep duration and wake behavior on workdays and workfree days and sleep disturbance. Phenotypic age acceleration (PhenoAgeAccel) was estimated as a biological age measure using 9 blood chemistry biomarkers.

RESULTS

Long sleep (>9 hours) and extremely short sleep (≤4 hours) on workdays were positively associated with PhenoAgeAccel, compared with optimal sleep duration (7-8 hours). Similar positive associations with PhenoAgeAccel were observed for sleep duration on workfree days and across the whole week. Both slightly evening and evening chronotypes were associated with faster PhenoAgeAccel compared to morning chronotype. Social jetlag and sleep disturbance were not associated with PhenoAgeAccel, while long corrected social jetlag was associated with faster PhenoAgeAccel. The associations of sleep duration, chronotype, and corrected social jetlag with PhenoAgeAccel appeared stronger among females than among males.

CONCLUSIONS

Findings suggest a U-shape relationship between sleep duration and biological aging; slightly evening and evening chronotypes may be risk factors for aging. Further studies are needed to confirm these findings.

Sleep regularity is a stronger predictor of mortality risk than sleep duration: A prospective cohort study

Abnormally short and long sleep are associated with premature mortality, and achieving optimal sleep duration has been the focus of sleep health guidelines. Emerging research demonstrates that sleep regularity, the day-to-day consistency of sleep-wake timing, can be a stronger predictor for some health outcomes than sleep duration. The role of sleep regularity in mortality, however, has not been investigated in a large cohort with objective data. We therefore aimed to compare how sleep regularity and duration predicted risk for all-cause and cause-specific mortality. We calculated Sleep Regularity Index (SRI) scores from > 10 million hours of accelerometer data in 60 977 UK Biobank participants (62.8 ± 7.8 years, 55.0% female, median[IQR] SRI: 81.0[73.8-86.3]). Mortality was reported up to 7.8 years after accelerometer recording in 1859 participants (4.84 deaths per 1000 person-years, mean (±SD) follow-up of 6.30 ± 0.83 years). Higher sleep regularity was associated with a 20%-48% lower risk of all-cause mortality (p < .001 to p = 0.004), a 16%-39% lower risk of cancer mortality (p < 0.001 to p = 0.017), and a 22%-57% lower risk of cardiometabolic mortality (p < 0.001 to p = 0.048), across the top four SRI quintiles compared to the least regular quintile. Results were adjusted for age, sex, ethnicity, and sociodemographic, lifestyle, and health factors. Sleep regularity was a stronger predictor of all-cause mortality than sleep duration, by comparing equivalent mortality models, and by comparing nested SRI-mortality models with and without sleep duration (p = 0.14-0.20). These findings indicate that sleep regularity is an important predictor of mortality risk and is a stronger predictor than sleep duration. Sleep regularity may be a simple, effective target for improving general health and survival.

Stress, epigenetics, and aging: Unraveling the intricate crosstalk

Aging, as a complex process involving multiple cellular and molecular pathways, is known to be exacerbated by various stresses. Because responses to these stresses, such as oxidative stress and genotoxic stress, are known to interplay with the epigenome and thereby contribute to the development of age-related diseases, investigations into how such epigenetic mechanisms alter gene expression and maintenance of cellular homeostasis is an active research area. In this review, we highlight recent studies investigating the intricate relationship between stress and aging, including its underlying epigenetic basis; describe different types of stresses that originate from both internal and external stimuli; and discuss potential interventions aimed at alleviating stress and restoring epigenetic patterns to combat aging or age-related diseases. Additionally, we address the challenges currently limiting advancement in this burgeoning field.

Associations between cardiorespiratory fitness and lifestyle-related factors with DNA methylation-based ageing clocks in older men: WASEDA'S Health Study

DNA methylation-based age estimators (DNAm ageing clocks) are currently one of the most promising biomarkers for predicting biological age. However, the relationships between cardiorespiratory fitness (CRF), measured directly by expiratory gas analysis, and DNAm ageing clocks are largely unknown. We investigated the relationships between CRF and the age-adjusted value from the residuals of the regression of DNAm ageing clock to chronological age (DNAmAgeAcceleration: DNAmAgeAccel) and attempted to determine the relative contribution of CRF to DNAmAgeAccel in the presence of other lifestyle factors. DNA samples from 144 Japanese men aged 65-72 years were used to appraise first- (i.e., DNAmHorvath and DNAmHannum) and second- (i.e., DNAmPhenoAge, DNAmGrimAge, and DNAmFitAge) generation DNAm ageing clocks. Various surveys and measurements were conducted, including physical fitness, body composition, blood biochemical parameters, nutrient intake, smoking, alcohol consumption, disease status, sleep status, and chronotype. Both oxygen uptake at ventilatory threshold (VO2 /kg at VT) and peak oxygen uptake (VO2 /kg at Peak) showed a significant negative correlation with GrimAgeAccel, even after adjustments for chronological age and smoking and drinking status. Notably, VO2 /kg at VT and VO2 /kg at Peak above the reference value were also associated with delayed GrimAgeAccel. Multiple regression analysis showed that calf circumference, serum triglyceride, carbohydrate intake, and smoking status, rather than CRF, contributed more to GrimAgeAccel and FitAgeAccel. In conclusion, although the contribution of CRF to GrimAgeAccel and FitAgeAccel is relatively low compared to lifestyle-related factors such as smoking, the results suggest that the maintenance of CRF is associated with delayed biological ageing in older men.

Mediating effects of DNA methylation in the association between sleep quality and infertility among women of childbearing age

BACKGROUND

This study aims to investigate the association between sleep quality and infertility among women and to explore the mediating effects of DNA methylation in this association.

METHODS

This study is a population-based case-control study. The relationship between sleep quality and infertility was investigated in women with anovulatory infertility (n = 43) and healthy controls (n = 43). Genome-wide DNA methylation was profiled from peripheral blood samples using the Illumina Infinium Human Methylation 850k BeadChip. Differentially methylated CpGs between cases and controls were identified using the ChAMP R package. The mediating effect of DNA methylation between sleep quality and infertility among women was investigated using the Bayesian estimation method provided by the R package "mediation".

RESULTS

The survey included 86 women of reproductive age, with 43 participants each in the case and control groups. The average age of the women was 27.6 ± 2.8 years (case group: 27.8 ± 3.0 years, control group: 27.4 ± 2.7 years). A total of 262 differentially methylated CpGs corresponding to 185 genes were identified. Difficulty falling asleep was a risk factor for infertility in women (OR = 3.69, 95%CI = 1.14, 11.99), and a causal mediation effect of DNA methylation CpGs was found. The mediating effect coefficient for cg08298632 was 0.10 (95%CI = 0.01-0.22), and the proportion of the total effect mediated by this methylation site increased to 64.3%.

CONCLUSION

These results suggest that DNA methylation CpGs (cg08298632) play a significant role in the relationship between difficulty falling asleep and infertility in females. These findings contribute to our understanding of the underlying mechanisms that connect difficulty falling asleep and infertility in women. Further studies are necessary to fully understand the biological significance and potential therapeutic applications of these findings. The identified DNA methylation sites provide new and valuable insights and potential targets for future studies aiming to prevent and treat female infertility.

Longitudinal assessment of the sleep suicide link in Veterans: methods and study protocol

Although sleep disruption has emerged as a theoretically consistent and empirically supported suicide risk factor, the mechanistic pathways underlying the sleep-suicide link are less understood. This paper describes the methodology of a study intended to examine longitudinal mechanisms driving the link between sleep and suicide in Veterans at elevated suicide risk. Participants will be 140 Veterans hospitalized for suicide attempt or ideation with plan and intent or those identified through the Suicide Prevention Coordinator (SPC) office as being at acute risk. After study enrollment, actigraphy and ecological momentary assessment (EMA) data will be collected for 8 weeks, with follow-up assessments occurring at 2, 4, 6, 8, and 26 weeks. Participants respond to EMA questionnaires, derived from psychometrically validated assessments targeting emotional reactivity, emotion regulation, impulsivity, suicide risk, and sleep timing constructs, five times a day. First and last daily EMA target sleep parameters including sleep quantity, quality, timing, nightmares, and nocturnal awakenings. During follow-up assessments, participants will complete self-report assessments and interviews consistent with EMA constructs and the Iowa Gambling Task. The primary outcome for aim 1 is suicide ideation severity and for the primary outcome for aim 2 is suicide behavior. Findings from this study will improve our understanding of the dynamic interactions among sleep disturbance, emotion reactivity/regulation, and impulsivity to inform conceptual Veteran sleep-suicide mechanistic models. Improved models will be critical to optimizing the precision of suicide prevention efforts that aim to intervene and mitigate risk in Veteran populations, especially during a period of acute risk.

Childhood sleep health and epigenetic age acceleration in late adolescence: Cross-sectional and longitudinal analyses

AIM

Investigate if childhood measures of sleep health are associated with epigenetic age acceleration in late adolescence.

METHODS

Parent-reported sleep trajectories from age 5 to 17, self-reported sleep problems at age 17, and six measures of epigenetic age acceleration at age 17 were studied in 1192 young Australians from the Raine Study Gen2.

RESULTS

There was no evidence for a relationship between the parent-reported sleep trajectories and epigenetic age acceleration (p ≥ 0.17). There was a positive cross-sectional relationship between self-reported sleep problem score and intrinsic epigenetic age acceleration at age 17 (b = 0.14, p = 0.04), which was attenuated after controlling for depressive symptom score at the same age (b = 0.08, p = 0.34). Follow-up analyses suggested this finding may represent greater overtiredness and intrinsic epigenetic age acceleration in adolescents with higher depressive symptoms.

CONCLUSION

There was no evidence for a relationship between self- or parent-reported sleep health and epigenetic age acceleration in late adolescence after adjusting for depressive symptoms. Mental health should be considered as a potential confounding variable in future research on sleep and epigenetic age acceleration, particularly if subjective measures of sleep are used.

The Role of Sleep and Eating Patterns in Adiposity Gain among Preschool-Aged Children

BACKGROUND

Short sleep duration is related to risk for obesity in preschool children. However, the underlying mechanism(s) are not clear.

OBJECTIVE

We evaluated the relationship between sleep characteristics with body composition, energetics and weight-regulating behaviors in preschool-aged children; and the longitudinal associations between children's sleep and eating patterns with body composition at 1-year follow-up.

METHODS

Data were drawn from a longitudinal study of 118 children aged 3-5 years. Sleep (duration, midpoint, regularity) and physical activity (PA) were measured by accelerometry over 6 consecutive days; total energy expenditure (TEE) using the doubly-labeled water method; body composition (fat mass, fat-free mass, and %body fat) by dual energy x-ray absorptiometry; and dietary intake (energy intake, timing) using two 24-h recalls. Multivariable regression was used to estimate interindividual associations of sleep parameters with body composition, PA, TEE and dietary outcomes; and to examine the relationship between sleep and dietary behaviors with body composition one year later.

RESULTS

Cross-sectionally, later sleep midpoint was associated with greater fat mass (0.33; 95% CI: 0.05, 0.60) and %body fat (0.92; 95% CI: 0.15, 1.70). Later sleep midpoint was associated with delayed morning (0.51; 95% CI: 0.28, 0.74) and evening meal times (0.41; 95% CI: 0.29, 0.53), higher nighttime (45.6; 95% CI: 19.7, 71.4), and lower morning (-44.8; 95% CI: -72.0, -17.6) energy intake. Longitudinally, shorter sleep duration (-0.02; 95% CI: -0.03, -0.00) and later meal timing (0.83; 95% CI: 0.24, 1.42) were associated with higher %body fat 1 year later.

CONCLUSIONS

Shorter sleep duration and later meal timing are associated with adiposity gain in preschoolers.

Counteracting aged DNA methylation states to combat ageing and age-related diseases

DNA methylation (DNAm) overwrites information about multiple extrinsic factors on the genome. Age is one of these factors. Age causes characteristic DNAm changes that are thought to be not only major drivers of normal ageing but also precursors to diseases, cancer being one of these. Although there is still much to learn about the relationship between ageing, age-related diseases and DNAm, we now know how to interpret some of the effects caused by age in the form of changes in methylation marks at specific loci. In fact, these changes form the basis of the so called "epigenetic clocks", which translate the genomic methylation profile into an "epigenetic age". Epigenetic age does not only estimate chronological age but can also predict the risk of chronic diseases and mortality. Epigenetic age is believed to be one of the most accurate metrics of biological age. Initial evidence has recently been gathered pointing to the possibility that the rate of epigenetic ageing can be slowed down or even reversed. In this review, we discuss some of the most relevant advances in this field. Expected outcome is that this approach can provide insights into how to preserve health and reduce the impact of ageing diseases in humans.

Role of sleep quality in the acceleration of biological aging and its potential for preventive interaction on air pollution insults: Findings from the UK Biobank cohort

Sleep has been associated with aging and relevant health outcomes, but the causal relationship remains inconclusive. In this study, we investigated the associations of sleep behaviors with biological ages (BAs) among 363,886 middle and elderly adults from UK Biobank. Sleep index (0 [worst]-6 [best]) of each participant was retrieved from the following six sleep behaviors: snoring, chronotype, daytime sleepiness, sleep duration, insomnia, and difficulties in getting up. Two BAs, the KDM-biological age and PhenoAge, were estimated by corresponding algorithms based on clinical traits, and their residual discrepancies with chronological age were defined as the age accelerations (AAs). We first observed negative associations between the sleep index and the two AAs, and demonstrated that the change of AAs could be the consequence of sleep quality using Mendelian randomization with genetic risk scores of sleep index and BAs. Particularly, a one-unit increase in sleep index was associated with 0.104- and 0.119-year decreases in KDM-biological AA and PhenoAge acceleration, respectively. Air pollution is another key driver of aging. We further observed significant independent and joint effects of sleep and air pollution (PM_2.5 and NO₂ ) on AAs. Sleep quality also showed a modifying effect on the associations of elevated PM_2.5 and NO₂  levels with accelerated AAs. For instance, an interquartile range increase in PM_2.5  level was associated with 0.009-, 0.044-, and 0.074-year increase in PhenoAge acceleration among people with high (5-6), medium (3-4), and low (0-2) sleep index, respectively. Our findings elucidate that better sleep quality could lessen accelerated biological aging resulting from air pollution.

Associations Between Sleep Quality and Health Span: A Prospective Cohort Study Based on 328,850 UK Biobank Participants

OBJECTIVE

To examine the associations between sleep quality and health span using a prospective cohort design based on the UK Biobank (UKB).

MATERIALS AND METHODS

This longitudinal cohort study enrolled 328,850 participants aged between 37 and 73 years from UKB to examine the associations between sleep quality and risk of terminated health span. End of health span was defined by eight events strongly associated with longevity (cancer, death, congestive heart failure, myocardial infarction, chronic obstructive pulmonary disease, stroke, dementia, and diabetes), and a sleep score was generated according to five sleep behavioral factors (sleep duration, chronotype, sleeplessness, daytime sleepiness, and snoring) to characterize sleep quality. The hazard ratio (HR) and 95% confidence intervals (CIs) were calculated by multivariate-adjusted Cox proportional hazards model. Moreover, we calculated population attributable risk percentage (PAR%) to reflect the public health significance of healthy sleep quality.

RESULTS

Compared with poor sleep quality, participants with healthy sleep quality had a 15% (HR: 0.85, 95% CI: 0.81-0.88) reduced risk of terminated health span, and those of less-healthy sleep quality had a 12% (HR: 0.88, 95% CI: 0.85-0.92) reduced risk. Linear trend results indicated that the risk of terminated health span decreased by 4% for every additional sleep score. Nearly 15% health span termination events in this cohort would have been prevented if a healthy sleep behavior pattern was adhered to (PAR%: 15.30, 95% CI: 12.58-17.93).

CONCLUSION

Healthy sleep quality was associated with a reduced risk of premature end of health span, suggesting healthy sleep behavior may extend health span. However, further studies are suggested for confirmation of causality and potential mechanism.

Investigation of the relationships between sleep behaviors and risk of healthspan termination: a prospective cohort study based on 323,373 UK-Biobank participants

OBJECTIVES

To examine the associations between four sleep behaviors and the risk of healthspan termination.

METHODS

This study included 323,373 participants, free of terminated healthspan at baseline, from the UK-Biobank (UKB). We applied multivariable-adjusted Cox regression models to estimate the risk of terminated healthspan based on four sleep behaviors (insomnia/sleeplessness, napping, daytime sleepiness, and difficulty getting up from bed), which were self-reported and measured on Likert scales from "usually" to "never/rarely" experiences. In this study, healthspan was defined based on eight events that are strongly associated with longevity (congestive heart failure, myocardial infarction, chronic obstructive pulmonary disease, stroke, dementia, diabetes, cancer, and death).

RESULTS

Participants who reported the following unhealthy sleep behaviors had a significantly higher risk of terminated healthspan: "usually experience sleeplessness/insomnia" (HR = 1.05, 95% CI: 1.03-1.07; P < 0.001); "usually nap" (HR = 1.22, 95% CI: 1.18-1.26; P < 0.01); "excessive daytime sleepiness" (HR = 1.25, 95% CI: 1.19-1.32; P < 0.001); and "difficult getting up from bed" (HR = 1.08, 95% CI: 1.05-1.10; P < 0.001). The corresponding population attributable risk percentage (PAR%) indicated that about 7% of healthspan termination in this cohort would have been eliminated if all participants had healthy sleep behaviors.

CONCLUSION

Participants who reported "usually experience sleeplessness/insomnia," "usually nap," "excessive daytime sleepiness," and "difficult getting up from bed" had increased risk of shortened healthspan. Therefore, adherence to healthy sleep behavior is significant for the extension of healthspan.

Potential reversal of epigenetic age using a diet and lifestyle intervention: a pilot randomized clinical trial

Manipulations to slow biological aging and extend healthspan are of interest given the societal and healthcare costs of our aging population. Herein we report on a randomized controlled clinical trial conducted among 43 healthy adult males between the ages of 50-72. The 8-week treatment program included diet, sleep, exercise and relaxation guidance, and supplemental probiotics and phytonutrients. The control group received no intervention. Genome-wide DNA methylation analysis was conducted on saliva samples using the Illumina Methylation Epic Array and DNAmAge was calculated using the online Horvath DNAmAge clock (2013). The diet and lifestyle treatment was associated with a 3.23 years decrease in DNAmAge compared with controls (p=0.018). DNAmAge of those in the treatment group decreased by an average 1.96 years by the end of the program compared to the same individuals at the beginning with a strong trend towards significance (p=0.066). Changes in blood biomarkers were significant for mean serum 5-methyltetrahydrofolate (+15%, p=0.004) and mean triglycerides (-25%, p=0.009). To our knowledge, this is the first randomized controlled study to suggest that specific diet and lifestyle interventions may reverse Horvath DNAmAge (2013) epigenetic aging in healthy adult males. Larger-scale and longer duration clinical trials are needed to confirm these findings, as well as investigation in other human populations.

Editorial Perspective: Adolescents' fragile sleep-shining light on a time of risk to mental health

As many other facets of life-biological, behavioral, psychological, cognitive, and social-undergo change during adolescence, so too does sleep. The context of sleep behavior is modified by alterations to underlying bioregulatory processes that challenge sleep's timing, regularity, and quantity. The buildup of sleep pressure during the day gets slower, opening the door for youth to stay awake later; however, the amount of sleep required does not diminish. Further, the circadian timing system delays, again providing the biological impetus for later sleep. When these changes meet societal demands for early wake, most teens cannot find a way to get enough sleep at a consistent time from night to night. Insufficient and irregular sleep provides a fragile foundation to support mental health.