Sleep in Normal Aging

Sleep patterns change with aging, independent of other factors, and include advanced sleep timing, shortened nocturnal sleep duration, increased frequency of daytime naps, increased number of nocturnal awakenings and time spent awake during the night, and decreased slow wave sleep. Most of these changes seem to occur between young and middle adulthood; sleep parameters remain largely unchanged among healthy older adults. The circadian system and sleep homeostatic mechanisms become less robust with normal aging. The amount and pattern of sleep-related hormone secretion change as well. The causes of sleep disturbances in older adults are multifactorial.

Validity of a single PTSD checklist item to screen for insomnia in survivors of critical illness

BACKGROUND

There is no insomnia screening tool validated in intensive care unit (ICU) survivors.

OBJECTIVES

To examine the validity of a single item from the PTSD checklist-Civilian version (PCL-C) to detect insomnia by Insomnia Severity Index (ISI) METHODS: We performed a secondary analysis of data from a longitudinal investigation in 120 medical-surgical ICU survivors. At 1 year post-ICU, patients completed ISI, PCL-C, and Medical Short-Form 12 (SF-12) by telephone. A single PCL-C item rates difficulty initiating or maintaining sleep over the past month. We compared performance characteristics of this PCL-C item to ISI-defined insomnia (ISI ≥15).

RESULTS

A score of ≥3 on the PCL-C sleep item exhibited 91% sensitivity and 67% specificity for ISI-defined insomnia (ISI ≥ 15), and it demonstrated construct validity by correlation to related QOL indices.

CONCLUSIONS

A single PCL-C sleep item score ≥ 3 is a reasonable screen to identify insomnia symptoms in ICU survivors.

Prevalence of restless legs syndrome during pregnancy: A systematic review and meta-analysis

Pregnant women are more likely to be affected by restless legs syndrome (RLS) than the general population. Restless legs syndrome during pregnancy is associated with adverse maternal and fetal outcomes. Currently unknown is the worldwide and regional prevalence of RLS in pregnant women. We performed a meta-analysis to provide a full profile of the prevalence of RLS during pregnancy. A systematic search of the PubMed, Medline, EMBASE, and Web of Science databases was performed to identify studies that were published up to April 2017, followed by random-effects meta-analyses. A total of 196 articles were identified, among which 27 longitudinal and cross-sectional observational studies with 51,717 pregnant subjects were included in the analysis. The pooled overall prevalence of RLS across all three trimesters was 21%. According to the regional classification of the World health organization, the prevalence of RLS during pregnancy in the European Region, Western Pacific Region, Eastern Mediterranean Region, and Region of the Americas was 22%, 14%, 30%, and 20%, respectively. The regional prevalence in the African Region and South-East Asia Region was not assessed because of insufficient data. We also analyzed the prevalence of RLS in the first, second, and third trimesters of pregnancy, and the rates of RLS were 8%, 16%, and 22%, respectively. We also found that the high prevalence of RLS decreased to 4% after delivery. No publication bias was found in these analyses. The findings emphasize the high occurrence of RLS during pregnancy. Future studies should examine the effects of RLS during pregnancy on maternal and fetal outcomes.

Transcriptional Signatures of Sleep Duration Discordance in Monozygotic Twins

Introduction

Habitual short sleep duration is associated with adverse metabolic, cardiovascular, and inflammatory effects. Co-twin study methodologies account for familial (eg, genetics and shared environmental) confounding, allowing assessment of subtle environmental effects, such as the effect of habitual short sleep duration on gene expression. Therefore, we investigated gene expression in monozygotic twins discordant for actigraphically phenotyped habitual sleep duration.

Methods

Eleven healthy monozygotic twin pairs (82% female; mean age 42.7 years; SD = 18.1), selected based on subjective sleep duration discordance, were objectively phenotyped for habitual sleep duration with 2 weeks of wrist actigraphy. Peripheral blood leukocyte (PBL) RNA from fasting blood samples was obtained on the final day of actigraphic measurement and hybridized to Illumina humanHT-12 microarrays. Differential gene expression was determined between paired samples and mapped to functional categories using Gene Ontology. Finally, a more comprehensive gene set enrichment analysis was performed based on the entire PBL transcriptome.

Results

The mean 24-hour sleep duration of the total sample was 439.2 minutes (SD = 46.8 minutes; range 325.4-521.6 minutes). Mean within-pair sleep duration difference per 24 hours was 64.4 minutes (SD = 21.2; range 45.9-114.6 minutes). The twin cohort displayed distinctive pathway enrichment based on sleep duration differences. Habitual short sleep was associated with up-regulation of genes involved in transcription, ribosome, translation, and oxidative phosphorylation. Unexpectedly, genes down-regulated in short sleep twins were highly enriched in immuno-inflammatory pathways such as interleukin signaling and leukocyte activation, as well as developmental programs, coagulation cascade, and cell adhesion.

Conclusions

Objectively assessed habitual sleep duration in monozygotic twin pairs appears to be associated with distinct patterns of differential gene expression and pathway enrichment. By accounting for familial confounding and measuring real life sleep duration, our study shows the transcriptomic effects of habitual short sleep on dysregulated immune response and provides a potential link between sleep deprivation and adverse metabolic, cardiovascular, and inflammatory outcomes.

Differential predictors of nighttime and daytime sleep complaints in older adults with comorbid insomnia and osteoarthritis pain

OBJECTIVES

Osteoarthritis (OA) is extremely common in older adults, affecting 50% of people aged 65 or older, and more than half of older adults with OA complain of significantly disturbed sleep. This study compared predictors of nighttime sleep complaints and daytime sleep-related consequences as measured by the Insomnia Severity Index (ISI) and Pittsburgh Sleep Quality Index (PSQI) in older adults with comorbid OA pain and insomnia.

METHODS

A secondary analysis of baseline data from a large longitudinal randomized controlled trial. Multivariate regression analyses were performed to test two sets of predictive models.

RESULTS

367 older adults (mean age 72.9±8.2years; female 78.5%) with OA and insomnia were included in this analysis. In Model 1, fatigue and depression predicted daytime sleep-related consequences for both ISI and PSQI. When measures of sleep and pain beliefs/attitudes were added (Model 2), fatigue, and sleep and pain beliefs/attitudes predicted nighttime sleep complaints for both ISI and PSQI; depression was no longer a significant predictor of ISI daytime consequences, but remained in the model for PSQI daytime consequences.

CONCLUSIONS

This study found both similarities and differences in factors predicting nighttime sleep complaints and daytime sleep-related consequences. Individual beliefs/attitudes about sleep and pain were stronger predictors of sleep difficulties than were depression and pain. Fatigue was the strongest and most consistent predictor associated with both nighttime sleep complaints and daytime sleep-related consequences regardless of the scale used to measure these concepts.

Feasibility and Efficacy of a Shared Yoga Intervention for Sleep Disturbance in Older Adults With Osteoarthritis

The purpose of the current study was to test the feasibility and efficacy of a shared yoga (SY) program for sleep disturbance in older adults with osteoarthritis (OA). Participants (ages 50 to 72) with insomnia related to OA were randomized to 12 weeks of SY (n = 9) or individual yoga (IY; n = 7). The sample was 53% male and 41% self-identified as a race other than White/Caucasian. The groups did not significantly differ in class attendance, home practice, or change scores on efficacy outcomes. Pre-post comparisons in all participants showed statistically significant improvements on the Insomnia Severity Index and Patient-Reported Outcomes Measurement System sleep disturbance scale. Findings support the overall feasibility of the program, both in the shared and individual formats. Efficacy data suggest that this yoga program may improve sleep, but given the study limitations, further research is needed to draw conclusions. [Journal of Gerontological Nursing, xx(x), xx-xx.].

Open-Loop Audio-Visual Stimulation (AVS): A Useful Tool for Management of Insomnia?

Audio Visual Stimulation (AVS), a form of neurofeedback, is a non-pharmacological intervention that has been used for both performance enhancement and symptom management. We review the history of AVS, its two sub-types (close- and open-loop), and discuss its clinical implications. We also describe a promising new application of AVS to improve sleep, and potentially decrease pain. AVS research can be traced back to the late 1800s. AVS's efficacy has been demonstrated for both performance enhancement and symptom management. Although AVS is commonly used in clinical settings, there is limited literature evaluating clinical outcomes and mechanisms of action. One of the challenges to AVS research is the lack of standardized terms, which makes systematic review and literature consolidation difficult. Future studies using AVS as an intervention should; (1) use operational definitions that are consistent with the existing literature, such as AVS, Audio-visual Entrainment, or Light and Sound Stimulation, (2) provide a clear rationale for the chosen training frequency modality, (3) use a randomized controlled design, and (4) follow the Consolidated Standards of Reporting Trials and/or related guidelines when disseminating results.

Report and Research Agenda of the American Geriatrics Society and National Institute on Aging Bedside-to-Bench Conference on Sleep, Circadian Rhythms, and Aging: New Avenues for Improving Brain Health, Physical Health, and Functioning

The American Geriatrics Society, with support from the National Institute on Aging and other funders, held its eighth Bedside-to-Bench research conference, entitled "Sleep, Circadian Rhythms, and Aging: New Avenues for Improving Brain Health, Physical Health and Functioning," October 4 to 6, 2015, in Bethesda, Maryland. Part of a conference series addressing three common geriatric syndromes-delirium, sleep and circadian rhythm (SCR) disturbance, and voiding dysfunction-the series highlighted relationships and pertinent clinical and pathophysiological commonalities between these three geriatric syndromes. The conference provided a forum for discussing current sleep, circadian rhythm, and aging research; identifying gaps in knowledge; and developing a research agenda to inform future investigative efforts. The conference also promoted networking among developing researchers, leaders in the field of SCR and aging, and National Institutes of Health program personnel.

Information without Implementation: A Practical Example for Developing a Best Practice Education Control Group

This article considers methodology for developing an education-only control group and proposes a simple approach to designing rigorous and well-accepted control groups. This approach is demonstrated in a large randomized trial. The Lifestyles trial (n = 367) compared three group interventions: (a) cognitive-behavioral treatment (CBT) for osteoarthritis pain, (b) CBT for osteoarthritis pain and insomnia, and (c) education-only control (EOC). EOC emulated the interventions excluding hypothesized treatment components and controlling for nonspecific treatment effects. Results showed this approach resulted in a control group that was highly credible and acceptable to patients. This approach can be an effective and practical guide for developing high-quality control groups in trials of behavioral interventions.

Comparison of Sleep Problems in Individuals with Spinal Cord Injury and Multiple Sclerosis

STUDY OBJECTIVES

Sleep problems are common in spinal cord injury (SCI) and multiple sclerosis (MS). However, the degree to which sleep problems differ between these distinct clinical populations has not been evaluated. In this study, we examined self-reported sleep problems in individuals with SCI and those with MS, and compared these clinical groups on the Medical Outcomes Study Sleep Scale (MOS-SS).

METHODS

Participants were 1,677 individuals (SCI = 581; MS = 1,096) enrolled in longitudinal study of self-reported health outcomes in SCI and MS. Univariate and multivariate analysis of covariance examined group differences on global sleep problems and domain-specific subscales of the MOS-SS.

RESULTS

Individuals with SCI reported an average of 30 fewer min of sleep per night (Sleep Quantity subscale) and significantly greater difficulty initiating and maintaining sleep (Sleep Disturbance subscale) compared to individuals with MS. However, groups did not differ on global sleep problems (Sleep Problems Index 9).

CONCLUSIONS

Although global sleep problems are more common in SCI and MS than in the general population, these groups exhibit differing sleep problem profiles, and thus may require unique treatment approaches to address the specific domains of sleep affected. For individuals with SCI, an additional focus on increasing sleep quantity and reducing sleep disruptions may be warranted.

Sleep Duration and Area-Level Deprivation in Twins

STUDY OBJECTIVES

We used quantitative genetic models to assess whether area-level deprivation as indicated by the Singh Index predicts shorter sleep duration and modifies its underlying genetic and environmental contributions.

METHODS

Participants were 4,218 adult twin pairs (2,377 monozygotic and 1,841 dizygotic) from the University of Washington Twin Registry. Participants self-reported habitual sleep duration. The Singh Index was determined by linking geocoding addresses to 17 indicators at the census-tract level using data from Census of Washington State and Census Tract Cartographic Boundary Files from 2000 and 2010. Data were analyzed using univariate and bivariate genetic decomposition and quantitative genetic interaction models that assessed A (additive genetics), C (common environment), and E (unique environment) main effects of the Singh Index on sleep duration and allowed the magnitude of residual ACE variance components in sleep duration to vary with the Index.

RESULTS

The sample had a mean age of 38.2 y (standard deviation [SD] = 18), and was predominantly female (62%) and Caucasian (91%). Mean sleep duration was 7.38 h (SD = 1.20) and the mean Singh Index score was 0.00 (SD = 0.89). The heritability of sleep duration was 39% and the Singh Index was 12%. The uncontrolled phenotypic regression of sleep duration on the Singh Index showed a significant negative relationship between area-level deprivation and sleep length (b = -0.080, P < 0.001). Every 1 SD in Singh Index was associated with a ∼4.5 min change in sleep duration. For the quasi-causal bivariate model, there was a significant main effect of E (b(0E) = -0.063; standard error [SE] = 0.30; P < 0.05). Residual variance components unique to sleep duration were significant for both A (b(0Au) = 0.734; SE = 0.020; P < 0.001) and E (b(0Eu) = 0.934; SE = 0.013; P < 0.001).

CONCLUSIONS

Area-level deprivation has a quasi-causal association with sleep duration, with greater deprivation being related to shorter sleep. As area-level deprivation increases, unique genetic and nonshared environmental residual variance in sleep duration increases.

National Sleep Foundation's updated sleep duration recommendations: final report

OBJECTIVE

To make scientifically sound and practical recommendations for daily sleep duration across the life span.

METHODS

The National Sleep Foundation convened a multidisciplinary expert panel (Panel) with broad representation from leading stakeholder organizations. The Panel evaluated the latest scientific evidence and participated in a formal consensus and voting process. Then, the RAND/UCLA Appropriateness Method was used to formulate sleep duration recommendations.

RESULTS

The Panel made sleep duration recommendations for 9 age groups. Sleep duration ranges, expressed as hours of sleep per day, were designated as recommended, may be appropriate, or not recommended. Recommended sleep durations are as follows: 14-17 hours for newborns, 12-15 hours for infants, 11-14 hours for toddlers, 10-13 hours for preschoolers, 9-11 hours for school-aged children, and 8-10 hours for teenagers. Seven to 9 hours is recommended for young adults and adults, and 7-8 hours of sleep is recommended for older adults. The self-designated basis for duration selection and critical discussions are also provided.

CONCLUSIONS

Consensus for sleep duration recommendations was reached for specific age groupings. Consensus using a multidisciplinary expert Panel lends robust credibility to the results. Finally, limitations and caveats of these recommendations are discussed.