Cellular aging and restorative processes: subjective sleep quality and duration moderate the association between age and telomere length in a sample of middle-aged and older adults

Investigation of the possible effects of night shift on telomere length and mtDNA copy number in nurses

In this study, we aimed to investigate the impacts of altered circadian rhythm on telomere length and mtDNA copy number (mtDNA-CN) in nurses working night shifts. In our study, 52 healthy nurses working in shifts at Ondokuz Mayıs University Hospital and 45 healthy control subjects working during the day were included. qRT-PCR technique was used for the determination of telomere length and mtDNA-CN. It was observed that the shift-work group had poor sleep quality (p = 0.004), feeling tired (p < 0.01) and stressed (p = 0.02) more than control group working during the day. Nurses working in shifts were found to have 1.18 times longer telomeres with respect to the control group working during the day (p = 0.005). When compared among shift workers, poor sleep quality and insufficient sleep duration shortened telomeres (r = 0.32; p = 0.02). There was no statistically significantdisparity regarding mtDNA-CN among the nurses working in shifts and the control group working during the day (p = 0.07). Insufficient sleep was associated with decreased mtDNA-CN when shift-working nurses were compared according to sleep quality (p = 0.006). Furthermore, mtDNA-CN of nurses with poor sleep quality was correlated with lower mtDNA-CN in comparison to nurses with good sleep quality (r = 0.284; p = 0.04). The mtDNA-CN of the nurses was positively associated with the sleep duration the night sleep before the night shift (r = 0.32; p = 0.02). Inadequate sleep duration and quality were observed to cause a reduction in mtDNA-CN of nurses. In conclusion, it has been observed that poor sleep quality and duration are related to shortened telomere length and decreased mtDNA-CN in night shift nurses.

The association of sleep duration and leukocyte telomere length in middle-aged and young-old adults: A cross-sectional study of UK Biobank

BACKGROUND

The relationships between sleep duration and aging-associated diseases are intricate. Leukocyte telomere length (LTL) is a biomarker of aging, while the association of sleep duration and LTL is unclear.

METHODS

The 310,091 study participants from UK Biobank were enrolled in this cross-sectional study. Restricted cubic splines (RCS) analysis was firstly performed to assess the nonlinear relationship between sleep duration and LTL. Sleep duration was then categorized into three groups: <7 h (short sleep duration), 7-8 h (reference group), and >8 h (long sleep duration) and multiple linear regression was applied to analyze the association of short sleep and long sleep duration with LTL. We further performed subgroup analyses stratified by sex, age, chronotype and snoring.

RESULTS

RCS showed an inverted J-shaped relationship between sleep duration and LTL. Compared with the reference group, the inverse association of long sleep duration and LTL was statistically significant in fully-adjusted model (P = 0.001). Subgroup analyses showed that this association was more apparent in people over 50 years (51-60 y: P = 0.002; >60 y: P = 0.005), in men (P = 0.022), and in people preferred evening chronotype (P = 0.001).

CONCLUSION

Compared with participants sleeping 7-8 h, those sleep longer than 8 h had shorter LTL in middle-aged and young-old adults. The negative association between long sleep duration and LTL was more apparent in older people, in men, and in people preferred evening chronotype.

Childhood unpredictability and sleep quality in adulthood: the mediating roles of life history strategy and perceived stress

Background

Early environmental risk have been found to be related to lifelong health. However, the impact of childhood unpredictability, a type of early environmental risk, on health, especially on sleep quality in adulthood, has not been adequately studied. The present study aimed to examine the relationship between childhood unpredictability and sleep quality in adulthood and to explore the possible mediating roles of life history strategy and perceived stress.

Methods

A cross-sectional study was conducted on 472 participants from a university in Zhejiang Province, China. The questionnaire inquired about demography, childhood unpredictability, life history strategy (Mini-K), perceived stress (14-item Perceived Stress Scale), and Sleep Quality (Pittsburgh Global Sleep Quality Index).

Results

Higher childhood unpredictability was significantly associated with worse sleep quality in adulthood. Moreover, the link between higher childhood unpredictability and worse sleep quality in adulthood was explained by the chain mediation of life history strategy and perceived stress.

Conclusion

In line with the life history theory, individuals who have experienced higher unpredictability in childhood tend to develop a faster life history strategy and become more sensitive to stress in adulthood, and subsequently suffer a decrease in sleep quality.

Association between modifiable lifestyle factors and telomere length: a univariable and multivariable Mendelian randomization study

BACKGROUND

Telomere length has long been recognized as a valuable biomarker of aging and is inversely correlated with chronological age. Various lifestyle factors have been implicated in telomere shortening or preservation; however, the association between lifestyle factors and telomere length remains controversial. To address this issue, we conducted a Mendelian randomization (MR) analysis to investigate the potential causal associations between multiple lifestyle factors and telomere length.

METHODS

Independent genetic variants strongly associated with lifestyle factors (tobacco smoking, sleep duration, insomnia, and physical activity) were selected as instrumental variables from corresponding genome-wide association studies (GWASs). Summary-level data for telomere length was obtained from a GWAS comprising 472,174 European ancestries. Univariable and multivariable MR analyses were performed to assess the relationships.

RESULTS

The genetic liability to lifetime smoking was robustly associated with shorter telomere length (odd ratio [OR]: 0.882; 95% confidence interval [CI]: 0.847-0.918). Genetically predicted insomnia was also linked to shorter telomere length (OR: 0.972; 95% CI: 0.959-0.985), while no significant association was observed between sleep duration and telomere length. Furthermore, a suggestive association was found between moderate-to-vigorous physical activity and longer telomere length (OR: 1.680; 95% CI: 1.115-2.531). In multivariable MR analyses, adjusting for potential mediators such as body mass index, type 2 diabetes, alcohol consumption, and alcohol use disorder, the associations of lifetime smoking and insomnia with telomere length remained robust.

CONCLUSION

Our findings suggest that smoking and insomnia may contribute to telomere shortening, while physical activity may play a role in telomere length maintenance. These findings underscore the importance of managing positive risk factors and adopting a healthy lifestyle to promote telomere health.

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.

Are pregnancy and parity associated with telomere length? A systematic review

BACKGROUND

Women's reproduction requires increased energy demands, which consequently may lead to cellular damage and aging. Hence, Telomere Length (TL), a biomarker of biological aging and health status may possibly serve as a biomarker of reproductive effort. The aim of this systematic review is to evaluate telomere dynamics throughout pregnancy and the association between parity and TL.

METHODS

A systematic search was conducted across seven databases including CINAHL, Cochrane, PsycINFO, Proquest, PubMed; Scopus; and Web of Science, using keywords and MeSH descriptors of parity and TL. Predefined inclusion and exclusion criteria were used to screen abstracts and titles. After the removal of duplicates, 3431 articles were included in the primary screening, narrowed to 194 articles included in the full-text screening. Consensus was reached for the 14 studies that were included in the final review, and the Newcastle-Ottawa scale (NOS) was utilized to assess the quality of the selected studies. A mini meta-analysis utilized JASP 0.17.3 software and included 4 applicable studies, comprising a total of 2564 participants to quantitatively assess the estimated effect size of parity on TL.

RESULTS

Of the 11 studies reviewed on parity and TL, four demonstrated a negative correlation; one - a positive correlation and six -found no correlation. Studies demonstrating a negative correlation encompassed rigorous methodological practices possibly suggesting having more children is associated with enhanced telomere attrition. Of the four longitudinal studies assessing telomere dynamics throughout pregnancy, most found no change in TL from early pregnancy to postpartum suggesting pregnancy does not affect TL from early pregnancy to early postpartum. The meta-analysis revealed a negative, yet, non-significant effect, of the estimated effect size of parity on TL(ES = -0.009, p = 0.126, CI -0.021, 0.03).

CONCLUSIONS

Studies assessing pregnancy, parity and TL yielded mixed results, most likely due to the different research methods utilized in each study. Improvements in study design to better understand the short-term effects of pregnancy on TL and the effect of parity on TL over time, include precise definitions of parity, comparisons of different age groups, inclusion of reproductive lifespan and statistically adjusting for potential confounders in the parity and TL relationship.

The state of brain activity modulates cerebrospinal fluid transport

Earlier studies based on 2-photon imaging have shown that glymphatic cerebrospinal fluid (CSF) transport is regulated by the sleep-wake cycle. To examine this association, we used 3DISCO whole-body tissue clearing to map CSF tracer distribution in awake, sleeping and ketamine-xylazine anesthetized mice. The results of our analysis showed that CSF tracers entered the brain to a significantly larger extent in natural sleep or ketamine-xylazine anesthesia than in wakefulness. Furthermore, awake mice showed preferential transport of CSF tracers in the rostro-caudal direction towards the cervical and spinal cord lymphatic vessels, and hence to venous circulation and excretion by the kidneys. The study extends the current literature by showing that CSF dynamics on the whole-body scale is controlled by the state of brain activity.

Endocrine and Epigenetic Regulation as Common Pathways Underlying the Genetic Basis of Sleep Traits and Longevity

The amount of sleep needed over one's lifespan is age dependent and not sleeping enough or sleeping in excess is associated with increased morbidity and mortality. Yet, the convergent molecular mechanisms that link longevity and sleep are largely unknown. We performed a gene enrichment study that (1) identified genes associated with both longevity and sleep traits and (2) determined molecular pathways enriched among these shared genes. We manually curated two sets of genes, one associated with longevity and aging and the other with sleep traits (e.g., insomnia, narcolepsy, sleep duration, chronotype, among others), with both gene lists heavily driven by hits from recent large-scale Genome-Wide Association Studies. There were 47 overlapping genes between the gene list associated with sleep traits (1064 genes total) and the genes associated with longevity (367 genes total), indicating significantly more overlap than expected by chance. An overrepresentation analysis identified enriched pathways that suggest endocrine and epigenetic regulation as potential shared mechanisms between sleep traits and longevity. Concordantly, functional network analysis retrieved two clusters, being one associated with proteins of nuclear functions and the other, with extracellular proteins. This overlapping gene set, and the highlighted biological pathways may serve as preliminary findings for new functional investigations of sleep and longevity shared genetic mechanisms.

Remission of insomnia in older adults treated with cognitive behavioral therapy for insomnia (CBT-I) reduces p16INK4a gene expression in peripheral blood: secondary outcome analysis from a randomized clinical trial

Late life insomnia may increase risk for accelerated biological aging. Intervening to treat insomnia may provide protection from biological aging by reducing the prevalence of senescent cells in the immune system, as indicated by gene expression of a marker of cellular senescence, p16INK4a. In the present study, we determine whether treatment of insomnia in older adults with cognitive behavioral therapy for insomnia (CBT-I) would reduce p16INK4a gene expression in peripheral blood mononuclear cells (PBMC), compared to a sleep education therapy (SET), an active comparator condition. Secondly, we investigate the relationship between sustained insomnia remission and reduced expression of p16INK4a. Participants 60 + years old with insomnia were enrolled in a randomized controlled trial and assigned to CBT-I or SET. Analyses of 231 older adults (CBT-I = 119; SET = 112) examine baseline, post (2 months), and 24 months gene expression of p16INK4a. Compared to baseline, expression of p16INK4a increased in the SET group over 24 months (P = 0.03), but showed no change in the CBT-I group. Those who received CBT-I and experienced sustained remission of insomnia had a significant decline in p16INK4a expression by 24 months compared to baseline (P = 0.02). Individuals not sustaining remission of insomnia exhibited overall increase expression of p16INK4a by 24 months (P = 0.03). In older adults with insomnia, p16INK4a increases over 24 months, while CBT-I treatment of insomnia mitigates the increase in p16INK4a. Further, sustained remission of insomnia using CBT-I leads to a decrease in p16INK4a. These results suggest that behavioral interventions that are effective at treating insomnia might reduce the population of senescent cells in circulating blood.

Relationship between Pittsburgh Sleep Quality Index and Retinopathy in Diabetic Women

PURPOSE

To examine the relationship between the presence and severity of retinopathy in women with diabetes mellitus and sleep quality assessed using Pittsburgh Sleep Quality Index (PSQI).

METHODS

Among 90 female patients with type 2 diabetes, 30 patients without retinopathy were classified into Group 1, 30 patients with nonproliferative diabetic retinopathy as Group 2, and 30 patients with proliferative diabetic retinopathy as Group 3. People who had a known sleep problem, had a history of using medication other than sleeping pills that would affect sleep, had lower or upper respiratory tract disease, had history of previous surgery, or were unable to answer the survey questions appropriately were excluded from the study.

RESULTS

The mean age was 52.6 ± 6.18 years in Group 1, 55.15 ± 8.15 years in Group 2, and 60.35 ± 5.93 years in Group 3. While no statistical difference was observed between Groups 1 and 2 (P = 0.27), a statistical difference was observed between both Groups 1 and 3 (P = 0.01) and Groups 2 and 3 (P = 0.02). PSQI scores were found to be 5.10 ± 1.07 in Group 1, 7.30 ± 2.34 in Group 2, and 6.70 ± 1.21 in Group 3. In terms of these scores, there was a statistical difference between Group 1 and both Group 2 (P = 0.01) and Group 3 (P = 0.01), while no difference was observed between Groups 2 and 3 (P = 0.31).

CONCLUSION

Although the presence of retinopathy significantly impairs sleep quality in diabeticwomen, no relationship was found between the severity of retinopathy and impaired sleep quality.

Associations of sleeping, sedentary and physical activity with phenotypic age acceleration: a cross-sectional isotemporal substitution model

BACKGROUND

Physical activity was believed to be associated with reduced aging among adults, while the competing nature of the physical activity and sedentary behavior has mainly been neglected in studies. We aimed to estimate the association of sleeping, sedentary behavior, and physical activity with aging among adults, considering the competing nature between variables of activity status.

METHODS

A total of 5288 participants who were 20 years or older from the National Health and Nutrition Examination Survey were involved. The questionnaire was used to collect data regarding sociodemographics (age, sex, ethnicity/race, and education), and lifestyle behaviors (smoking, drinking). The Global Physical Activity Questionnaire was used to measure self-reported time for sedentary behavior, walking/bicycling, and moderate-to-vigorous physical activity (MVPA). The sleeping duration was obtained via interview. Phenotypic age acceleration (PhenoAgeAccel) was calculated as an aging index using nine chemistry biomarkers. Isotemporal substitution models using multivariable linear regression to examine the associations of sleeping, sedentary behavior, and physical activity with PhenoAgeAccel, stratified by MVPA (< 150 min/week, ≥ 150 min/week).

RESULTS

Thirty minutes per day spent on sedentary behavior was positively associated with PhenoAgeAccel (β = 0.07, 95% CI: 0.04, 0.11), and 30 min/day spent on leisure-time MVPA was adversely associated with PhenoAgeAccel (β =  - 0.55, 95% CI: - 0.73, - 0.38). Replacing 30 min/day sedentary behaviors with 30 min/day of MVPA (β = -3.98, 95% CI: -6.22, -1.74) or 30 min/day of walking/bicycling (β = -0.89, 95% CI: -1.10, -0.68) was adversely associated with PhenoAgeAccel. Substituting 30 min/day of walking/bicycling for 30 min/day of leisure-time MVPA was positively associated with PhenoAgeAccel (β = 3.09, 95% CI: 0.93, 5.25).

CONCLUSION

Sedentary behavior was positively associated with aging. Replacing sedentary behaviors with walking/bicycling or MVPA was adversely associated with aging among adults.

The association between sleep quality and telomere length: A systematic literature review

Several sleep parameters present an elevated risk for processes that contribute to cellular aging. Short sleep duration, sleep apnoea, and insomnia are significantly associated with shorter telomeres, a biological marker of cellular aging. However, there has been no review or analysis of studies that have examined the association between the psychological construct of sleep quality and telomere length. The present study aimed to provide a systematic review of the association between sleep quality and telomere length. A systematic review of English articles was conducted using MEDLINE/PubMed, PsycINFO, Google Scholar, and Web of Science electronic databases, with the final search conducted on 3rd September 2021. Search terms included sleep quality, poor sleep, insomnia, sleep difficulties, sleep issue*, non-restorative sleep, telomere*, cellular aging, and immune cell telomere length. Study eligibility criteria included human participants aged 18 years or older and a reproducible methodology. Study appraisal and synthesis were completed using a systematic search in line with a PICOS approach (P = Patient, problem, or population; I = Intervention, prognostic factor, exposure; C = Comparison, control, or comparator; O = Outcomes; S = Study designs). Twenty-two studies met review inclusion criteria. Qualitative synthesis of the literature indicated insufficient evidence overall to support a significant association between sleep quality and telomere length. Limitations across studies were addressed, such as the assessment of examined constructs. Findings highlight important targets for future research, including the standardised operationalisation of the sleep quality construct and experimental study designs. Research in this area has clinical significance by identifying possible mechanisms that increase the risk for age-related disease and mortality. PROSPERO Registration No.: CRD 42021233139.

Good perceived sleep quality protects against the raised risk of respiratory infection during sleep restriction in young adults

STUDY OBJECTIVES

Prospectively examine the association between sleep restriction, perceived sleep quality (PSQ) and upper respiratory tract infection (URTI).

METHODS

In 1318 military recruits (68% males) self-reported sleep was assessed at the beginning and end of a 12-week training course. Sleep restriction was defined as an individualized reduction in sleep duration of ≥2 hours/night compared with civilian life. URTIs were retrieved from medical records.

RESULTS

On commencing training, approximately half of recruits were sleep restricted (52%; 2.1 ± 1.6 h); despite the sleep debt, 58% of recruits with sleep restriction reported good PSQ. Regression adjusted for covariates showed that recruits commencing training with sleep restriction were more likely to suffer URTI during the course (OR = 2.93, 95% CI 1.29-6.69, p = .011). Moderation analysis showed this finding was driven by poor PSQ (B = -1.12, SE 0.50, p = .023), as no significant association between sleep restriction and URTI was observed in recruits reporting good PSQ, despite a similar magnitude of sleep restriction during training. Associations remained in the population completing training, accounting for loss to follow-up. Recruits reporting poor PSQ when healthy at the start and end of training were more susceptible to URTI (OR = 3.16, 95% CI 1.31-7.61, p = .010, vs good PSQ).

CONCLUSION

Good perceived sleep quality was associated with protection against the raised risk of respiratory infection during sleep restriction. Studies should determine whether improvements in sleep quality arising from behavioral sleep interventions translate to reduced respiratory infection during sleep restriction.

Children who sleep more may have longer telomeres: evidence from a longitudinal population study in Spain

BACKGROUND

Inadequate sleep duration has been suggested as a chronic stressor associated with changes in telomere length (TL). This study aimed to explore the association between sleep duration and TL using the INMA birth cohort study data.

METHODS

A total of 1014 children were included in this study (cross-sectional: 686; longitudinal: 872). Sleep duration (h/day) was reported by caregivers at 4 years and classified into tertiles (7-10 h/day; >10-11 h/day; >11-14 h/day). Leucocyte TL at 4 and 7-9 years were measured using quantitative PCR methods. Multiple robust linear regression models, through log-level regression models, were used to report the % of difference among tertiles of sleep duration.

RESULTS

In comparison to children who slept between >10 and 11 h/day, those in the highest category (more than 11 h/day) had 8.5% (95% CI: 3.56-13.6) longer telomeres at 4 years. Longitudinal analysis showed no significant association between sleep duration at 4 years and TL at 7-9 years.

CONCLUSION

Children who slept more hours per day had longer TL at 4 years independently of a wide range of confounder factors. Environmental conditions, such as sleep duration, might have a major impact on TL during the first years of life.

IMPACT

Telomere length was longer in children with longer sleep duration (>11 h/day) independently of a wide range of confounder factors at age 4 and remained consistent by sex. Sleep routines are encouraged to promote positive child development, like the number of hours of sleep duration. Considering the complex biology of telomere length, future studies still need to elucidate which biological pathways might explain the association between sleep duration and telomere length.

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.

Association between sleep parameters and longitudinal shortening of telomere length

BACKGROUND

The relationship between sleep parameters and longitudinal shortening of telomere length is unclear. This study aimed to investigate the relationship between sleep parameters and the shortening of leukocyte telomere length (LTL) over a year.

METHODS

Among the participants in the validation cohort of the Korea Brain Aging Study for the Early Diagnosis and Prediction of Alzheimer's Disease, participants who measured both baseline and follow-up (two years later) of LTL were analyzed. They were dichotomized according to the degree of LTL attrition over two years. Clinical characteristics were compared between the faster and slower LTL shortening groups (cut-off points: -0.710 kbp, n = 119 each). Multivariable logistic regression analyses were performed to determine independent relationships between faster shortening of LTL length and sleep parameters.

RESULTS

A total of 238 participants, aged 55-88 years, were included. Participants with faster LTL shortening had a shorter duration of sleep (P = 0.013) and longer sleep latency (P = 0.007). Among the components of the PSQI, subjective measures of sleep quality, sleep latency, sleep duration, and sleep efficiency were significantly worse in participants with faster LTL shortening. Multivariate logistic regression analysis showed that sleep duration (per hour, OR = 0.831, 95% CI = 0.698-0.989), sleep latency (per minute, OR = 1.013, 95% CI = 1.002-1.024), global PSQI score (OR = 1.134, 95% CI = 1.040-1.236), shortest sleep duration (OR = 5.173, 95% CI = 1.563-17.126), and lowest sleep efficiency (OR = 7.351, 95% CI = 1.943-27.946) were independently associated with faster LTL shortening.

CONCLUSIONS

Poor sleep quality, specifically short sleep duration, long sleep latency, and low sleep efficiency were associated with faster longitudinal shortening of LTL.

Cancer-related accelerated ageing and biobehavioural modifiers: a framework for research and clinical care

A growing body of evidence indicates that patients with cancer who receive cytotoxic treatments (such as chemotherapy or radiotherapy) have an increased risk of accelerated physical and cognitive ageing. Furthermore, accelerated biological ageing is a suspected driving force behind many of these observed effects. In this Review, we describe the mechanisms of biological ageing and how they apply to patients with cancer. We highlight the important role of specific behavioural factors, namely stress, sleep and lifestyle-related factors such as physical activity, weight management, diet and substance use, in the accelerated ageing of patients with cancer and cancer survivors. We also present a framework of how modifiable behaviours could operate to either increase the risk of accelerated ageing, provide protection, or promote resilience at both the biological level and in terms of patient-reported outcomes.

Changes in telomere length and serum neurofilament light chain levels in female patients with chronic insomnia disorder

STUDY OBJECTIVES

The aims of this study were to explore changes in the telomere length (relative telomere repeat copy/single-copy gene [T/S ratio]) and serum neurofilament light chain (sNfL) levels in female patients with chronic insomnia disorder (CID), examine their relationships with emotional abnormalities and cognitive impairment, and determine whether these 2 indicators were independently associated with sleep quality.

METHODS

The CID group contained 80 patients diagnosed with CID, and 51 individuals constituted a healthy control group. Participants completed sleep, emotion, and cognition assessments. Telomere length was detected through quantitative real-time polymerase chain reaction. Enzyme-linked immunosorbent assay was used to determine sNfL concentrations.

RESULTS

Relative to the healthy control group, the CID group had elevated Pittsburgh Sleep Quality Index, Hamilton Anxiety Scale-14, and Hamilton Depression Rating Scale-17 scores and reduced Montreal Cognitive Assessment scale scores, a decreased T/S ratio, and an increased sNfL concentration. Subgroup analysis according to various CID-associated sleep factors showed that poor sleep performance corresponded to a lower T/S ratio. Higher anxiety levels and more cognitive dysfunction correlated with shorter telomere lengths. The T/S ratio negatively correlated with age, whereas the sNfL concentration positively correlated with age in the CID group. The Pittsburgh Sleep Quality Index score negatively correlated with the T/S ratio but did not correlate with sNfL levels. Multiple linear regression analysis showed that the T/S ratio had a negative and independent effect on Pittsburgh Sleep Quality Index scores.

CONCLUSIONS

The CID group had shorter telomeres and higher sNfL concentrations, and reduced telomere length independently affected sleep quality.

CITATION

Ren C-Y, Liu P-P, Li J, et al. Changes in telomere length and serum neurofilament light chain levels in female patients with chronic insomnia disorder. J Clin Sleep Med. 2022;18(2):383-392.

Longitudinal Analysis of Sleep Disturbance in Breast Cancer Survivors

BACKGROUND

Breast cancer survivors (BCS) often report poor sleep quality and wakefulness throughout the night as the greatest challenges experienced during and posttreatment.

OBJECTIVES

This study aimed to elucidate characteristics of sleep disturbances and determine potential predictors that affect sleep disturbances in BCS for 2 years postchemotherapy.

METHODS

This is a secondary analysis of data from the EPIGEN study, which longitudinally examined sociodemographic and cancer-related factors, lifestyle, symptom characteristics, and epigenetic factors at baseline prior to chemotherapy (T1), the midpoint (T2), 6-month (T3), 1-year (T4), and 2-year (T5) time points postchemotherapy. Temporal lifestyle changes, symptom characteristics, and epigenetic factors were explored using linear mixed-effects models with a random intercept. A linear regression model was fitted to identify significant predictors of sleep disturbances at each time point.

RESULTS

In 74 BCS with an average age of 51 years and 70% non-Hispanic White, BCS experienced severe sleep disturbances at T2, which gradually improved over time. Significant temporal changes in midsleep awakenings, early awakenings, and fatigue at work were observed, with disturbances being elevated at T2. Anxiety (T1, T2, and T4), fatigue (T3 and T4), and perceived stress (T3) were significant predictors after adjusting for radiation therapy, surgery, and adjuvant endocrine therapy.

DISCUSSION

This study highlights that predictors of sleep disturbances change over time, with anxiety being a factor earlier in the treatment trajectory (prechemotherapy) and continuing over time with fatigue and perceived stress being involved later in the treatment trajectory. Our results indicate that symptom management strategies to address sleep disturbances should be tailored to the temporal factors that may change in severity during active treatment and early survivorship period. Findings gained from this study on sleep disturbance patterns and the potential risk factors can be incorporated into clinical practice in planning education and developing interventions.

Effect of Physical Activity, Smoking, and Sleep on Telomere Length: A Systematic Review of Observational and Intervention Studies

Aging is a risk factor for several pathologies, restricting one’s health span, and promoting chronic diseases (e.g., cardiovascular and neurodegenerative diseases), as well as cancer. Telomeres are regions of repetitive DNA located at chromosomal ends. Telomere length has been inversely associated with chronological age and has been considered, for a long time, a good biomarker of aging. Several lifestyle factors have been linked with telomere shortening or maintenance. However, the consistency of results is hampered by some methodological issues, including study design, sample size, measurement approaches, and population characteristics, among others. Therefore, we aimed to systematically review the current literature on the effects of three relevant lifestyle factors on telomere length in human adults: physical activity, smoking, and sleep. We conducted a qualitative systematic review of observational and intervention studies using the Preferred Reporting Item for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The systematic literature search covered articles published in MEDLINE and EMBASE databases (from 2010 to 2020). A total of 1400 studies were identified; 83 were included after quality control. Although fewer sedentary activities, optimal sleep habits, and non- or ex-smoker status have been associated with less telomere shortening, several methodological issues were detected, including the need for more targeted interventions and standardized protocols to better understand how physical activity and sleep can impact telomere length and aging. We discuss the main findings and current limitations to gain more insights into the influence of these lifestyle factors on the healthy aging process.

Sleep and Biological Aging: A Short Review

Obtaining healthy quantity and quality of sleep is a key to optimal mental and physical health, and cumulative evidence points to a role of sleep loss and sleep disturbances as a contributor to early disease onset and shortened survival. We propose that the molecular underpinnings that drive this risk are key drivers of the biological aging process, including altering metabolism, promoting damage, failure in repair and restoration machinery, leaving lasting impacts on cellular health, telomere loss, cellular senescence, and ultimately system failure. Our premise is that biological aging machinery is altered by sleep, and in the current short review we highlight the existing literature that links sleep with aging biology thought to drive age-related disease and shorten lifespan.

Obstructive Sleep Apnea as an Acceleration Trigger of Cellular Senescence Processes through Telomere Shortening

Obstructive sleep apnea (OSA) is chronic disorder which is characterized by recurrent pauses of breathing during sleep which leads to hypoxia and its two main pathological sequelae: oxidative stress and chronic inflammation. Both are also associated with cellular senescence. As OSA patients present with higher prevalence of age-related disorders, such as atrial hypertension or diabetes mellitus type 2, a relationship between OSA and accelerated aging is observable. Furthermore, it has been established that these OSA are associated with telomere shortening. This process in OSA is likely caused by increased oxidative DNA damage due to increased reactive oxygen species levels, DNA repair disruptions, hypoxia, chronic inflammation, and circadian clock disturbances. The aim of the review is to summarize study outcomes on changes in leukocyte telomere length (LTL) in OSA patients and describe possible molecular mechanisms which connect cellular senescence and the pathophysiology of OSA. The majority of OSA patients are characterized by LTL attrition due to oxidative stress, hypoxia and inflammation, which make a kind of positive feedback loop, and circadian clock disturbance.

Sleep disparities during the COVID-19 pandemic: An investigation of AIAN, Asian, Black, Latinx, and White young adults

OBJECTIVES

This study investigates race-related disparities in sleep duration and quality among diverse young adults during the coronavirus 2019 (COVID-19) pandemic.

DESIGN & SETTING

Online cross-sectional study of young adults in the United States in April 2020.

PARTICIPANTS

About 547 American Indian/Alaskan Native (AIAN), Asian, Black, Latinx, and White young adults ages 18-25 years.

MEASUREMENTS

Participants completed measures of sleep duration and quality, coronavirus victimization distress, depression, age, sex/gender, employment status, essential worker status, student status, residential region, socioeconomic status, concerns about contracting coronavirus and CDC health risks.

RESULTS

Black young adults reported the largest disparity in sleep duration and quality. For sleep duration, AIAN, Asian, White, and Latinx young adults reported approximately one additional hour of sleep compared to Black respondents. Mediation analyses suggest that disparities in sleep duration between Asian and Black young adults may be explained by the higher likelihood of Black respondents being essential workers. For sleep quality, Latinx, White, AIAN, and Asian young adults reported higher levels than Black respondents. Including coronavirus victimization distress as an intervening pathway decreased the effect for Asian and White respondents on sleep quality, suggesting that coronavirus victimization distress partially explains Black and Asian, as well as Black and White differences in sleep quality.

CONCLUSIONS

Black young adults reported the shortest sleep duration and lowest levels of sleep quality relative to AIAN, Asian, Latinx and White peers. Interpersonal experiences of coronavirus victimization and structural inequities may partially explain disparities during the COVID-19 pandemic.

Postpartum sleep loss and accelerated epigenetic aging

BACKGROUND

Insufficient sleep has been linked to accelerated biological aging in adults, providing a possible mechanism through which sleep may influence disease risk. In the current paper, we test the hypothesis that short sleep in postpartum would predict older biological age in women one year post birth, as indicated by accelerated epigenetic aging.

METHODS

As part of a larger study of pregnancy and postpartum health (Healthy Babies Before Birth, HB3), 33 mothers provided blood samples for epigenetic aging clock estimates. intrinsic epigenetic age acceleration (IEAA), extrinsic apigenetic age acceleration, phenotypic epigenetic age acceleration (PEAA), GrimAge, DNAmPAI-1, and DNAm telomere length (TL) were calculated using established protocols. Sleep duration was categorized as insufficient sleep (<7 hours per night) or healthy sleep duration (7+ hours per night). Sleep quality was determined using the Pittsburgh Sleep Quality Index (Global score >5).

RESULTS

Maternal postpartum sleep duration at 6 months, but not 12 months, following a birth was predictive of older 12-month IEAA, B (SE) = 3.0 (1.2), P = .02, PEAA, B (SE) = 7.3 (2.0), P = .002, and DNAmTL, B (SE) = -0.18 (0.07), P = .01, but not other indices, all P> .127. Self-reported poor sleep quality at 6 and 12 months was not significantly related to epigenetic age.

CONCLUSIONS

These findings suggest that insufficient sleep duration during the early postpartum period is associated with accelerated biological aging. As the sample size is small, additional research is warranted with a larger sample size to replicate these findings.

Telomere Length and Oxidative Stress and Its Relation with Metabolic Syndrome Components in the Aging

Simple Summary

A link between telomere length and some age-related diseases has been identified, including metabolic syndrome. So far, there is no mechanism to explain the origin or cause of telomere shortening in this syndrome; however, oxidative stress is a constant factor. Therefore, we reviewed scientific evidence that supported the association between oxidative stress and telomere length dynamics, also examining how each of the metabolic syndrome components individually affects the length. In this regard, there is strong scientific evidence that an increase in the number of metabolic syndrome components is associated with a shorter telomere length, oxidative damage at the lipid and DNA level, and inflammation, as well as its other components, such as obesity, hyperglycemia, and hypertension, while for dyslipidemia, there is a little more discrepancy. The difficulty for the correct treatment of metabolic syndrome lies in its multifactorial nature. Hence, there is a need to carry out more studies on healthy lifestyles during aging to prevent and reduce oxidative damage and telomere wear during aging, and consequently the progression of chronic degenerative diseases, thus improving the living conditions of older people.

Abstract

A great amount of scientific evidence supports that Oxidative Stress (OxS) can contribute to telomeric attrition and also plays an important role in the development of certain age-related diseases, among them the metabolic syndrome (MetS), which is characterised by clinical and biochemical alterations such as obesity, dyslipidaemia, arterial hypertension, hyperglycaemia, and insulin resistance, all of which are considered as risk factors for type 2 diabetes mellitus (T2DM) and cardiovascular diseases, which are associated in turn with an increase of OxS. In this sense, we review scientific evidence that supports the association between OxS with telomere length (TL) dynamics and the relationship with MetS components in aging. It was analysed whether each MetS component affects the telomere length separately or if they all affect it together. Likewise, this review provides a summary of the structure and function of telomeres and telomerase, the mechanisms of telomeric DNA repair, how telomere length may influence the fate of cells or be linked to inflammation and the development of age-related diseases, and finally, how the lifestyles can affect telomere length.

Premature Aging Among Trauma Survivors-The Longitudinal Implications of Sleep Disruptions on Telomere Length and Cognitive Performance

OBJECTIVES

Sleep is necessary for brain function as well as physical and cognitive processes. Sleep disruptions, common with aging, intensify among trauma survivors. Moreover, former prisoners-of-war (ex-POWs) often experience premature aging. This study investigates the longitudinal effects of sleep disruptions for ex-POWs in relation to cognitive performance and telomere length as well as between cognition and telomeres.

METHOD

This study included Israeli veterans from the 1973 Yom Kippur War who participated in four assessments (1991, 2003, 2008, 2015): (a) ex-POWs (n = 99), and (b) veterans who not were captured (controls) (n = 101). Among both groups, sleep disruptions were assessed using a self-report item in all four assessments. Cognitive performance was assessed using the Montreal Cognitive Assessment (MOCA) and telomere length was assessed via total white blood cells (leukocytes) from whole blood samples using Southern blot, both were measured only among ex-POWs in 2015. We conducted descriptive statistics, repeated measures, correlations, and path analyses.

RESULTS

Sleep disruptions were related to lower cognitive performance but not to shorter telomeres. Moreover, cognitive performance and telomere length were found to be related when sleep disruptions were taken into consideration.

CONCLUSION

Interpersonal trauma was shown to be a unique experience resulting in sleep disruptions over time, leading to cognitive impairment. These findings highlight the importance of viewing trauma survivors at high-risk for sleep disruptions. Therefore, it is imperative to inquire about sleep and diagnose cognitive disorders to help identify and treat premature aging.

Live fast, die young and sleep later: Life history strategy and human sleep behavior

Background and objectives

Life History Theory (LHT) describes trade-offs that organisms make with regard to three investment pathways: growth, maintenance and reproduction. In light of the reparative functions of sleep, we examine sleep behaviors and corresponding attitudes as proximate manifestations of an individual's underlying relative prioritization of short-term reproduction versus long-term maintenance.

Methodology

We collected survey data from 568 participants across two online studies having different participant pools. We use a mixture of segmented and hierarchical regression models, structural equation modeling and machine learning to infer relationships between sleep duration/quality, attitudes about sleep and biodemographic/psychometric measures of life history strategy (LHS).

Results

An age-mediated U- or V-shaped relationship appears when LHS is plotted against habitual sleep duration, with the fastest strategies occupying the sections of the curve with the highest mortality risk: < 6.5 hr (short sleep) and > 8.5 hr (long sleep). LH 'fastness' is associated with increased sleepiness and worse overall sleep quality: delayed sleep onset latency, more wakefulness after sleep onset, higher sleep-wake instability and greater sleep duration variability. Hedonic valuations of sleep may mediate the effects of LHS on certain sleep parameters.

Conclusions and implications

The costs of deprioritizing maintenance can be parameterized in the domain of sleep, where 'life history fastness' corresponds with sleep patterns associated with greater senescence and mortality. Individual differences in sleep having significant health implications can thus be understood as components of lifelong trajectories likely stemming from calibration to developmental circumstances. Relatedly, hedonic valuations of sleep may constitute useful avenues for non-pharmacological management of chronic sleep disorders.Lay Summary: Sleep is essential because it allows the body to repair and maintain itself. But time spent sleeping is time that cannot be spent doing other things. People differ in how much they prioritize immediate rewards, including sociosexual opportunities, versus long-term goals. In this research, we show that individual differences in sleep behaviors, and attitudes toward sleep, correspond with psychological and behavioral differences reflecting such differing priorities. Orientation toward sleep can thus be understood as part of the overall lifetime strategies that people pursue.

Discrepancies in self-reported and actigraphy-based sleep duration are associated with self-reported insomnia symptoms in community-dwelling older adults

OBJECTIVES

To establish agreement between self-reported and actigraphy-based total sleep time (TST). To determine the impact of self-reported sleep problems on these measurements.

DESIGN

Cross-sectional study using data from Wave 3 of The Irish Longitudinal Study on Ageing (2014-2015).

PARTICIPANTS

Community-dwelling older adults, aged ≥50 years, with self-reported sleep information and ≥4 days of actigraphy-based TST (n = 1520).

MEASUREMENT

Self-reported total sleep time, daytime sleepiness, insomnia symptoms (trouble falling asleep, trouble waking too early) measured during a structured self-interview. Actigraphy-based total TST was collected using GENEactiv wrist-worn accelerometers. Demographic characteristics and health information were controlled for. Analyses included descriptive statistics, reliability and agreement analysis using paired t-tests, intra-class correlations and Bland-Altman analysis. Linear regression was used to model associations with measurement discrepancies.

RESULTS

Participants reported that they slept 7.0 hours (SD: 1.4, Range: 2.0-13.0 hours) on average, compared to 7.7 hours (SD: 1.2 hours, Range: 3.0-13.0 hours) recorded by accelerometry. Trouble falling asleep or waking too early "most of the time" were associated with under-reporting of sleep by 2.3, and 2.2 hours respectively. Agreement between measurements had an intra-class correlation of 0.18 and wide 95% limits of agreement (-3.90 to 2.55 hours). Under-reporting of sleep was independently associated with insomnia symptoms.

CONCLUSION

The agreement between self-reported and actigraphy-based TST in community dwelling older adults was low. Self-reported insomnia symptoms were independently associated with under-reporting of sleep. Studies seeking to measure sleep duration should consider inclusion of questions measuring experience of insomnia symptoms to account for potential influence on measurements.

Telomere shortening velocity of patients administered with hypnotics is accelerated in a gender-differential manner

The telomere length and its distribution were compared between patients administered with and without hypnotics to see if regular administration of hypnotics is associated with their aging-related somatic telomere shortening. Male patients presented significant shortening of telomere length of circulating leukocytes in association with age (-41.9 bp/year, p = 0.045) in contrast with controls (-18.3 kb/year, p = 0.155). On the other hand, female patients presented no significant shortening of telomere length with aging (-16.4 bp/year, p = 0.372) in contrast with controls (-55.9 bp/year, p = 0.00005). These results suggested that regular administration of hypnotics is associated with aging progression in a gender-related manner. The administration of hypnotics could be an indicator as the somatic aging status and for the screening of background lifestyle-associated diseases promoting biological aging.

Objectively measured sleep and telomere length in a population-based cohort of children and midlife adults

STUDY OBJECTIVES

Poor sleep patterns in older adults are associated with chromosomal telomere shortening, a marker of cellular senescence. However, studies have relied on self-reported sleep characteristics, with few data for younger individuals. We investigated whether sleep measured via actigraphy was cross-sectionally associated with telomere length in children and midlife adults.

METHODS

A population-based sample of 1874 11-12 year olds and midlife adults (mean age 44 years, SD 5.1) had biological and physical assessments at centers across Australia in 2015-2016. Sleep characteristics, including duration, onset, offset, day-to-day variability, and efficiency, were derived from actigraphy. Relative telomere length (T/S ratio) was measured by quantitative polymerase chain reaction on genomic DNA from peripheral blood. Multivariable regression models estimated associations, adjusting for prespecified confounders.

RESULTS

Both sleep and telomere data were available for 728 children and 1070 adults. Mean (SD) T/S ratio was 1.09 (0.55) in children and 0.81 (0.38) in adults. T/S ratio was not predicted by sleep duration (β 0.04, 95% confidence interval [CI] -0.02 to 0.09, p = .16, children; β -0.004, 95% CI -0.03 to 0.02, p = .70, adults) or most other sleep metrics. The only exception was a weak association between later sleep timing (the midpoint of sleep onset and offset) and longer telomeres in adults (β 0.03, 95% CI 0.01 to 0.06, p = .01).

CONCLUSIONS

Objective sleep characteristics show no convincing associations with telomere length in two largely healthy populations up to at least midlife. Sleep-telomere associations may be a late-life occurrence or may present only with a trigger such as presence of other morbidities.

Loneliness and Telomere Length: Immune and Parasympathetic Function in Associations With Accelerated Aging

BACKGROUND

Lonely people's heightened risks for chronic health conditions and early mortality may emerge in part through cellular aging. Lonelier people have more severe sympathetic responses to acute stress, increasing their risk for herpesvirus reactivation, a possible path to shorter telomeres. Parasympathetic function may modulate this risk.

PURPOSE

The current study aimed to examine the associations among loneliness, herpesvirus reactivation, and telomere length, with parasympathetic activity as a moderator, in healthy middle-aged and older adults.

METHODS

A sample of 113 healthy men and women of ages 40-85 provided blood samples that were assayed for telomere length, as well as the latent herpesviruses cytomegalovirus (CMV) and Epstein-Barr virus (EBV). They also provided heart rate variability (HRV), a measure of parasympathetic activity, and reported on their feelings of loneliness.

RESULTS

Lonelier people with lower HRV (i.e., lower parasympathetic activity) had greater CMV reactivation and shorter telomeres compared with their less lonely counterparts, above and beyond demographics, health behaviors, resting heart rate, and social network size. However, loneliness was not associated with viral reactivation or telomere length among those with higher HRV. In turn, greater CMV and EBV reactivation was associated with shorter telomeres.

CONCLUSIONS

Taken together, these data implicate parasympathetic function in novel links between loneliness and accelerated cellular aging.

Delayed sleep-onset and biological age: late sleep-onset is associated with shorter telomere length

STUDY OBJECTIVES

We evaluated the relationship between leukocyte telomere length (LTL) and sleep duration, insomnia symptoms, and circadian rhythm, to test whether sleep and chronobiological dysregulations are associated with cellular aging.

METHODS

Data from the Netherlands Study of Depression and Anxiety (N = 2,936) were used at two waves 6 years apart, to measure LTL. Telomeres shorten during the life span and are important biomarkers for cellular aging. LTL was assessed by qualitative polymerase chain reaction and converted into base pair number. Sleep parameters were: sleep duration and insomnia symptoms from the Insomnia Rating Scale. Circadian rhythm variables were: indication of Delayed Sleep Phase Syndrome (DSPS), mid-sleep corrected for sleep debt on free days (MSFsc), sleep-onset time, and self-reported chronotype, from the Munich Chronotype Questionnaire. Generalized estimating equations analyzed the associations between LTL, sleep, and chronobiological factors, adjusted for baseline age, sex, North European ancestry, and additionally for current smoking, depression severity, obesity, and childhood trauma.

RESULTS

Indicators of delayed circadian rhythm showed a strong and consistent effect on LTL, after adjustment for sociodemographic and health indicators. Late MSFsc (B = -49.9, p = .004), late sleep-onset time (B = -32.4, p = .001), indication of DSPS (B = -73.8, p = .036), and moderately late chronotype in adulthood (B = -71.6, p = .003) were associated with significantly shorter LTL across both waves; whereas sleep duration and insomnia symptoms were not. Extremely early chronotype showed significantly less LTL shortening than intermediate chronotype (B = 161.40, p = .037). No predictors showed accelerated LTL attrition over 6 years.

CONCLUSIONS

Individuals with delayed circadian rhythm have significantly shorter LTL, but not faster LTL attrition rates.

Psychosocial Stressors and Telomere Length: A Current Review of the Science

A growing literature suggests that exposure to adverse social conditions may accelerate biological aging, offering one mechanism through which adversity may increase risk for age-related disease. As one of the most extensively studied biological markers of aging, telomere length (TL) provides a valuable tool to understand potential influences of social adversity on the aging process. Indeed, a sizeable literature now links a wide range of stressors to TL across the life span. The aim of this article is to review and evaluate this extant literature with a focus on studies that investigate psychosocial stress exposures and experiences in early life and adulthood. We conclude by outlining potential biological and behavioral mechanisms through which psychosocial stress may influence TL, and we discuss directions for future research in this area.

Association of sleep quality with telomere length, a marker of cellular aging: A retrospective cohort study of older adults in the United States

BACKGROUND

Sleep quality is a risk factor for age-related diseases, and although the underlying mechanisms remain unclear, the effects of poor sleep quality on telomere length (TL) may play a role.

OBJECTIVE

The objective of the study was to evaluate the independent association between sleep quality and salivary TL in a large sample of older adults.

DESIGN

We adopted a retrospective cohort design, and participants comprised 5,268 adults drawn from the Health and Retirement Study. We used the 2006 (baseline) and 2008 (follow-up) waves. Baseline sleep quality was assessed using 4 Likert scale questions (trouble falling asleep, waking up during the night, waking up too early and not being able to fall sleep again, and feeling well rested in the morning). The TL was assessed using the T/S ratio, a continuous variable. The associations between sleep quality and T/S were assessed using multivariable ordinary least squares regressions. All analyses were adjusted for demographics, lifestyle characteristics, psychosocial, and other factors.

RESULTS

Overall, 16% reported never feeling well rested in the morning; 25.7% of respondents always had trouble waking during the night; and 12.8% always had trouble waking up too early in the morning. Respondents who never felt rested in the morning had significantly shorter TL than those who always felt rested in the morning (adjusted beta = -0.08, standard error = 0.03, P < .01). The composite sleep measure was not significantly associated with shorter TL.

CONCLUSIONS

In this cohort of older adults, not feeling well rested in the morning was significantly and inversely associated with TL; however, the composite measure of sleep quality was not significantly associated with TL. These findings suggest a potential connection between one of the measures of impaired sleep and reduction in TL, a marker of cellular aging that has been linked to multiple chronic conditions.

Sleep and inflammation: partners in sickness and in health

The discovery of reciprocal connections between the central nervous system, sleep and the immune system has shown that sleep enhances immune defences and that afferent signals from immune cells promote sleep. One mechanism by which sleep is proposed to provide a survival advantage is in terms of supporting a neurally integrated immune system that might anticipate injury and infectious threats. However, in modern times, chronic social threats can drive the development of sleep disturbances in humans, which can contribute to the dysregulation of inflammatory and antiviral responses. In this Review, I describe our current understanding of the relationship between sleep dynamics and host defence mechanisms, with a focus on cytokine responses, the neuroendocrine and autonomic pathways that connect sleep with the immune system and the role of inflammatory peptides in the homeostatic regulation of sleep. Furthermore, I discuss the therapeutic potential of harnessing these reciprocal mechanisms of sleep-immune regulation to mitigate the risk of inflammatory and infectious diseases.

Racial discrimination and telomere shortening among African Americans: The Coronary Artery Risk Development in Young Adults (CARDIA) Study

OBJECTIVE

Telomeres are protective sequences of DNA capping the ends of chromosomes that shorten over time. Leukocyte telomere length (LTL) is posited to reflect the replicative history of cells and general systemic aging of the organism. Chronic stress exposure leads to accelerated LTL shortening, which has been linked to increased susceptibility to and faster progression of aging-related diseases. This study examined longitudinal associations between LTL and experiences of racial discrimination, a qualitatively unique source of minority psychosocial stress, among African Americans.

METHOD

Data are from 391 African Americans in the Coronary Artery Risk Development in Young Adults (CARDIA) Telomere Ancillary Study. We examined the number of domains in which racial discrimination was experienced in relation to LTL collected in Years 15 and 25 (Y15: 2000/2001; Y25: 2010/2011). Multivariable linear regression examined if racial discrimination was associated with LTL. Latent change score analysis (LCS) examined changes in racial discrimination and LTL in relation to one another.

RESULTS

Controlling for racial discrimination at Y15, multivariable linear regression analyses indicated that racial discrimination at Y25 was significantly associated with LTL at Y25. This relationship remained robust after adjusting for LTL at Y15 (b = -.019, p = .015). Consistent with this finding, LCS revealed that increases in experiences of racial discrimination were associated with faster 10-year LTL shortening (b = -.019, p = .015).

CONCLUSIONS

This study adds to evidence that racial discrimination contributes to accelerated physiologic weathering and health declines among African Americans through its impact on biological systems, including via its effects on telomere attrition. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Association of sleep-disordered breathing with total healthcare costs and utilization in older men: the Outcomes of Sleep Disorders in Older Men (MrOS Sleep) study

STUDY OBJECTIVES

To determine the associations of sleep-disordered breathing (SDB) with subsequent healthcare costs and utilization including inpatient and post-acute care facility stays among community-dwelling older men.

METHODS

Participants were 1,316 men (mean age 76.1 [SD = 5.7] years) in the Outcomes of Sleep Disorders in Older Men (MrOS sleep) study (from December 2003 to March 2005), who were enrolled in a Medicare Fee-For-Service plan. Primary SDB measures including apnea hypopnea index (AHI) and oxygen desaturation index (ODI) were collected using in-home level 2 polysomnography. Incident healthcare costs and utilization were determined from claims data in the subsequent 3-year period post-MrOS sleep visit.

RESULTS

Five hundred and twenty-nine (40.2%) men had at least one hospitalization in the 3-year period. Compared with those without sleep apnea (AHI < 5/hour), men with moderate to severe sleep apnea (AHI ≥ 15/hour) had a higher odds of all-cause hospitalization (odds ratio [OR] adjusted for age and site 1.43, 95% confidence interval [CI]: 1.07-1.90). This association was slightly attenuated after further adjustment for traditional prognostic factors including education, body mass index, comorbid medical conditions, and health status (OR = 1.36; 95% CI: 1.01-1.83). Similar associations were observed for ODI. However, measures of SDB were not related to subsequent healthcare costs (total or outpatient) or odds of post-acute skilled nursing facility stay.

CONCLUSIONS

Older men with SDB have an increased risk of hospitalization, not entirely explained by the greater prevalence of comorbid conditions, but not higher subsequent total healthcare costs. These findings indicate a need to evaluate the impact of SDB treatment on subsequent healthcare utilization.

A Cross-Sectional Analysis of Telomere Length and Sleep in the Women's Health Initiative

Telomere length is a heritable marker of cellular age that is associated with morbidity and mortality. Poor sleep behaviors, which are also associated with adverse health events, may be related to leukocyte telomere length (LTL). We studied a subpopulation of 3,145 postmenopausal women (1,796 European-American (EA) and 1,349 African-American (AA)) enrolled in the Women's Health Initiative in 1993-1998 with data on Southern blot-measured LTL and self-reported usual sleep duration and sleep disturbance. LTL-sleep associations were analyzed separately for duration and disturbance using weighted and confounder-adjusted linear regression models in the entire sample (AAs + EAs; adjusted for race/ethnicity) and in racial/ethnic strata, since LTL differs by ancestry. After adjustment for covariates, each additional daily hour of sleep beyond 5 hours, approximately, was associated with a 27-base-pair (95% confidence interval (CI): 6, 48) longer LTL in the entire sample. Associations between sleep duration and LTL were strongest among AAs (adjusted β = 37, 95% CI: 4, 70); a similar, nonsignificant association was observed for EAs (adjusted β = 20, 95% CI: -7, 48). Sleep disturbance was not associated with LTL in our study. Our models did not show departure from linearity (quadratic sleep terms: P ≥ 0.55). Our results suggest that longer sleep duration is associated with longer LTL in postmenopausal women.

Obstructive sleep apnea, nighttime arousals, and leukocyte telomere length: the Multi-Ethnic Study of Atherosclerosis

STUDY OBJECTIVES

Sleep disturbances and sleep apnea are associated with increased vulnerability to age-related disease, altering molecular pathways affecting biological aging. Telomere length captures one component of biological aging. We evaluated whether objectively assessed sleep and sleep apnea relate to leukocyte telomere length (LTL) in the Multi-Ethnic Study of Atherosclerosis (MESA).

METHODS

Men and women aged 44-84 years (n = 672) from the MESA Stress and MESA Sleep studies underwent polysomnography and 7 day actigraphy (at Exam 5) and assessment of LTL (at baseline [Exam 1] and about 10 years later [Exam 5]).

RESULTS

General linear models adjusting for age, sex, race/ethnicity, BMI, physical activity, and smoking found that severe obstructive sleep apnea (OSA; apnea-hypopnea index > 30) was cross-sectionally associated with shorter LTL (p = 0.007). Modest associations of shorter LTL with less rapid eye movement sleep, more stage 1 sleep, wake after sleep onset >30 min, and long sleep duration were found, but these effects were diminished after adjusting for lifestyle and OSA. Exploratory analyses found that higher arousal index at Exam 5 was associated with greater LTL decline over the prior 10 years (p = 0.004).

CONCLUSIONS

OSA was associated with shorter LTL. Individuals with high-arousal frequency had greater leukocyte telomere attrition over the prior decade. These findings suggest that sleep apnea and sleep fragmentation are associated with accelerated biological aging.

The Sleep-Immune Crosstalk in Health and Disease

Sleep and immunity are bidirectionally linked. Immune system activation alters sleep, and sleep in turn affects the innate and adaptive arm of our body's defense system. Stimulation of the immune system by microbial challenges triggers an inflammatory response, which, depending on its magnitude and time course, can induce an increase in sleep duration and intensity, but also a disruption of sleep. Enhancement of sleep during an infection is assumed to feedback to the immune system to promote host defense. Indeed, sleep affects various immune parameters, is associated with a reduced infection risk, and can improve infection outcome and vaccination responses. The induction of a hormonal constellation that supports immune functions is one likely mechanism underlying the immune-supporting effects of sleep. In the absence of an infectious challenge, sleep appears to promote inflammatory homeostasis through effects on several inflammatory mediators, such as cytokines. This notion is supported by findings that prolonged sleep deficiency (e.g., short sleep duration, sleep disturbance) can lead to chronic, systemic low-grade inflammation and is associated with various diseases that have an inflammatory component, like diabetes, atherosclerosis, and neurodegeneration. Here, we review available data on this regulatory sleep-immune crosstalk, point out methodological challenges, and suggest questions open for future research.

At the forefront of psychoneuroimmunology in pregnancy: Implications for racial disparities in birth outcomes: PART 2: Biological mechanisms

As reviewed in Part 1 of this two part review, birth prior to full term is a substantial public health issue. In the US, ˜400,000 babies per year are born preterm (< 37 weeks), while>1 million are early term (37-38^6/7 weeks) and remarkable racial disparities in shortened gestation are observed among African Americans as compared to Whites. Biomechanisms linking stressor exposures with birth outcomes are increasingly being explicated. The current paper reviews the mechanistic role of maternal biological functioning in the link between behavioral exposures and birth outcomes. These include the inter-related roles of neuroendocrine function, inflammatory regulation, biological aging, and the microbiome. An integrative approach which addresses both behavioral and biological factors within the same study, carefully considers the role of race/ethnicity, and rigorously defines birth outcomes (e.g., spontaneous versus medically-indicated and inclusive of early term birth) is needed to move research in this field toward better mechanistic understanding and clinical application.

Implications of sleep disturbance and inflammation for Alzheimer's disease dementia

Nearly half of all adults older than 60 years of age report sleep disturbance, as characterised either by reports of insomnia complaints with daytime consequences, dissatisfaction with sleep quality or quantity, or the diagnosis of insomnia disorder. Accumulating evidence shows that sleep disturbance contributes to cognitive decline and might also increase the risk of Alzheimer's disease dementia by increasing β-amyloid burden. That sleep disturbance would be a candidate risk factor for Alzheimer's disease might seem surprising, given that disturbed sleep is usually considered a consequence of Alzheimer's disease. However, a bidirectional relationship between sleep and Alzheimer's disease is supported by advances in our understanding of sleep disturbance-induced increases in systemic inflammation, which can be viewed as an early event in the course of Alzheimer's disease. Inflammation increases β-amyloid burden and is thought to drive Alzheimer's disease pathogenesis. Improved understanding of the mechanisms linking sleep disturbance and Alzheimer's disease risk could facilitate the identification of targets for prevention, given that both sleep disturbance and inflammatory activation might be modifiable risk factors for Alzheimer's disease.

Long Sleep Duration, Insomnia, and Insomnia With Short Objective Sleep Duration Are Independently Associated With Short Telomere Length

STUDY OBJECTIVES

We aimed to determine the association between short telomere length, sleep parameters, and sleep disorders in an adult general population sample.

METHODS

As part of the EPISONO cohort (São Paulo, Brazil), 925 individuals answered questionnaires, underwent a full-night polysomnography and clinical assessment, and had peripheral blood collected for DNA extraction. Insomnia was diagnosed based on the Diagnostic and Statistical Manual of Mental Disorders, 4th edition; and obstructive sleep apnea was defined according to apnea-hypopnea index. For the objective insomnia phenotype, we combined insomnia diagnosis with total sleep time from polysomnography with a cutoff of 360 minutes, allowing the classification of six groups. Self-reported sleep duration was used to classify the individuals as short (< 6 hours), average (6 to 8 hours) and long (> 8 hours) sleepers. The leukocyte telomere length was measured using quantitative real-time polymerase chain reaction. Based on its distribution, we considered leukocyte telomere length < 10th percentile as short telomere and leukocyte telomere length ≥ 10th percentile as non-short telomere.

RESULTS

After adjusting for sex, age, and body mass index, only insomnia disorder (odds ratio [OR] = 2.654, 95% confidence interval [CI] = 1.025-6.873, P = .044), insomnia disorder total sleep time < 360 minutes (OR = 4.205, 95% CI = 1.097-16.117, P = .036) and long sleepers (OR = 2.177, 95% CI = 1.189- 3.987, P = .012) were associated with short telomere.

CONCLUSIONS

Our findings support the existence of an association among insomnia, insomnia phenotype, and self-reported long sleep duration with the maintenance of telomere length.

COMMENTARY

A commentary on this article appears in this issue on page 1975.

Stronger Association between Insomnia Symptoms and Shorter Telomere Length in Old HIV-Infected Patients Compared with Uninfected Individuals

Growing evidence suggests that HIV infection may accelerate biological aging. Insomnia symptoms, particularly in later life, exacerbate cellular aging. We examined the association between insomnia symptoms and leukocyte telomere length (LTL), and further explored how this association was affected by HIV serostatus and age. Data were assessed from 244 HIV-infected individuals ≥40 years and 244 HIV-uninfected individuals who were frequency-matched by age, gender and education level. Insomnia symptoms were assessed by responses to four sleep-related questions covering the past month. We performed multivariable linear regression with logarithmically transformed LTL and reported exponentiated coefficients. HIV-infected individuals had shorter LTL compared to uninfected individuals (geometric mean 0.82 vs 0.89, P=0.052), and this association remained after adjustment for gender, education level, and smoking history (-7.4%, P=0.051) but markedly attenuated after additional adjustment for insomnia and depressive symptoms (-3.7%, P=0.367). Significant interactions between age group (55-82 vs 40-54 years) and insomnia symptoms on LTL were observed in the HIV-infected individuals (-28.4%, P=0.033) but not the uninfected (-17.9%, P=0.250). After stratifying by age group, LTL was independently associated with insomnia symptoms in those 55 years and older among the HIV-infected individuals (-24.5%, P=0.026) but not those 40-54 years old (-9.8%, P=0.428). Our findings suggest that elevated insomnia and depressive symptoms may partly explain the correlation between HIV serostatus and shorter LTL. Significant association between insomnia and shorter LTL observed in elderly HIV-infected but not in uninfected individuals suggest that such adverse effect may begin at an earlier age or is more pronounced in HIV-infected individuals but requires further investigation.

Dietary Fiber and Telomere Length in 5674 U.S. Adults: An NHANES Study of Biological Aging

The relationship between fiber intake and telomere length was evaluated using a cross-sectional design and an NHANES sample of 5674 U.S. adults. Another purpose was to test the impact of potential confounders on the association. Fiber consumption was measured using a 24 h recall and telomere length was indexed using the quantitative polymerase chain reaction method. Overall, the U.S. adults had low fiber intake (median: 6.6 g per 1000 kcal)—less than one-half the recommendation of the Dietary Guidelines for Americans. With age, gender, race, housing status, and misreported energy intake controlled, the relationship between fiber intake per 1000 kcal and telomere length was linear (F = 9.5, p = 0.0045). Specifically, for each 1 g increment in fiber intake per 1000 kcal, telomeres were 8.3 base pairs longer. Because each additional year of chronological age was associated with telomeres that were 15.5 base pairs shorter, results suggest that a 10 g increase in fiber intake per 1000 kcal would correspond with telomeres that are 83 base pairs longer. On average, this would equate to 5.4 fewer years of biologic aging (83 ÷ 15.5). With smoking, BMI, alcohol use, and physical activity controlled, as well as the other covariates, each 10 g increment in fiber accounted for telomeres that were 67 base pairs longer (F = 7.6, p = 0.0101), a biologic aging difference of about 4.3 years. In conclusion, significant fiber consumption accounts for longer telomeres and less biologic aging than lower levels of fiber intake.

Poor sleep during early pregnancy increases subsequent risk of gestational diabetes mellitus

OBJECTIVES

To examine the relationship between poor sleep quality during pregnancy and the risk of gestational diabetes mellitus (GDM).

METHODS

A total of 4066 singleton pregnant women from the Tongji Maternal and Child Health Cohort (TMCHC) without overt diabetes before pregnancy were analyzed. Sleep quality and duration during early pregnancy were self-reported by enrolled women at their first antenatal care visit before 16 weeks of gestation. Gestational diabetes mellitus (GDM) was assessed with a 75-g, 2-h oral glucose tolerance test at 24-28 weeks of gestation. Information about self-reported sleep quality and duration in mid-pregnancy were also collected at this time. Odds ratios (OR) and 95% CIs were calculated by multivariable logistic regression models, and adjusted for potential confounders to estimate the effect of poor sleep quality and the interaction between sleep quality and duration on the development of GDM. Stratified analyses were performed according to age, parity, family history of diabetes and napping.

RESULTS

A total of 335 (8.2%) participants were diagnosed with GDM. Poor sleep quality was reported in 259 (6.4%) women during early pregnancy and 248 (6.1%) in mid-pregnancy. The risk of GDM was increased in women with poor sleep quality during early pregnancy (OR 1.77, 95% CI 1.20-2.61). No association was found between poor sleep quality during mid-pregnancy and the risk of GDM. The risk of GDM was highest in women with poor sleep and longer nighttime sleep duration during early pregnancy (OR 2.27, 95% CI 1.20-4.29) when compared with those who reported good sleep and 7.0-8.5 h of sleep duration per night. Stratified analysis found that the association between poor sleep quality in early pregnancy and the risk of GDM was stronger among women aged ≥30 years (OR 2.35, 95% CI 1.35-4.09) and those with a family history of diabetes (OR 4.02, 95% CI 1.54-10.48).

CONCLUSIONS

Poor sleep quality during early pregnancy was associated with an increased risk of GDM. Screening for and treating sleep problems in early pregnancy could potentially reduce the risk of GDM.

The effect of the severity of obstructive sleep apnea syndrome on telomere length

Aging is associated with an increase in the prevalence of obstructive sleep apnea syndrome (OSAS) as well as the shortening of telomeres. It is known that OSAS-related factors are stimuli that can contribute to the acceleration of cellular senescence. Thus, the present study aimed to compare the leukocyte telomere length (LTL) between OSAS patients and controls, as well as to verify the correlation between LTL and sleep parameters. We used DNA extracted of 928 individuals from EPISONO to measure the LTL by the quantitative real-time polymerase chain reaction. All individuals were subjected to one full-night polysomnography. LTL was significantly shorter in OSAS patients compared to controls. The results showed negative correlations between LTL and the following variables: apnea-hypopnea index, respiratory disturbance index, desaturation index and wake after sleep onset. LTL was positively correlated with sleep efficiency, total sleep time, basal, minimum and maximum oxygen saturation. Lastly, it was observed that OSAS severity was associated with shorter LTL even after adjusting for sex, age, years of schooling, body mass index, diabetes, stroke and heart attack. In conclusion, our study indicates the presence of an association between LTL and OSAS and a significant impact of severity of OSAS in telomeres shortening.

Leukocyte telomere length variation in different stages of schizophrenia

Recent research has demonstrated that telomere maintenance might be a key integrating point for the cumulative effect of genetic and environmental factors in patients with first-episode psychosis (FEP) and schizophrenia (SCZ). Eighty-one participants with antipsychotic-naïve FEP, 173 with SCZ and 438 HC were enrolled in this study. Psychiatric diagnosis was assessed using the Semi-Structured Clinical Interview for DSM-IV Axis-I (SCID-I). The Positive and Negative Syndrome Scale (PANSS), Young Mania Rating Scale (YMRS) and Calgary Depression Scale for Schizophrenia (CDSS) were used to measure symptoms severity. Telomere length (TL) was determined using a multiplex qPCR assay. After adjustment for age, years of education, and smoking status, we found that patients with SCZ had longer TL (relative ratio (RR) = 1.08) than the HC group (RR = 1.00, Wald χ² = 12.48, p = 0.002). Further, non-remitted SCZ patients presented longer TL (RR = 1.00) compared to remitted SCZ (RR = 0.88, Wald χ² = 7.20, p = 0.007). TL in patients also correlated to psychopathology assessment in terms of total (p = 0.003) and positive PANSS scores (p = 0.001). No correlation with negative PANSS, YMRS, and CDSS or effects of medication was found on TL. Although the exact pathways underlying longer TL in SCZ patients remain unclear, these findings raise more questions than answers and suggest that TL may be of immense value on SCZ progression. Further studies are required to investigate the association of TL in FEP and SCZ.