Nighttime Sleep Research Articles

The effects, mechanisms and strategies of daytime napping on athletes: a narrative review.

Athletes generally suffer from insufficient sleep duration, lower sleep efficiency, and a high overall prevalence of insomnia. Daytime napping has been demonstrated to supplement nighttime sleep in athletes; however, recent controversial findings warrant further consideration. This review synthesized existing studies on the effects of daytime naps on athletes, explored potential mechanisms of daytime napping, and analyzed instances of ineffective interventions or negative outcomes. Daytime napping functions as a restorative strategy to counteract sleep deprivation or the post-lunch dip, assisting athletes in recovering anaerobic capacity, agility, reaction time, and alertness, with potential mechanisms including the reduction of sleepiness through adherence to circadian rhythms, decreased subjective soreness and fatigue attributed to autonomic functioning, and improved respiratory performance. The optimal nap period occurs between 13:00 and 15:00, with a 5-6h interval between morning awakening and nap initiation. Depending on the athlete's nighttime sleep, opt for a 20 ~ 40 or 60 ~ 90 min nap with at least 60min between the nap and subsequent exercise to reduce sleep inertia. The intervention efficacy of daytime napping was correlated with exercise intensity. A nap program must be developed based on the specific athletic demands of the sport in practical application.

Early identification of sleep phenotypes in infants by videosomnography: a cross-sectional study.

We propose to identify different sleep phenotypes in infancy, relying on auto-videosomnography metrics. In this cross-sectional study, objective infant sleep metrics of six hundred twenty-three infants aged 9 to 13 months, recruited among users of Nanit baby-monitor in the United States, were obtained from Nanit auto-videosomnography (1 week of data averaged) in the child's natural sleep environment. A cluster analysis was conducted to group infants based on sleep metrics. Three reproducible and stable sleep phenotypes were identified: Long Sleepers (n.338), Interrupted Sleepers (n.130) and Short Sleepers (n.155). All sleep metrics were statistically significant different in the three groups. Long Sleepers had longer nighttime sleep duration than Interrupted and Short Sleepers. Interrupted Sleepers presented more awakenings than Short and Long Sleepers, and similarly more parental interventions. Short Sleepers presented later bedtimes and earlier wake up times when compared with Long and Interrupted Sleepers. Nighttime sleep efficiency was better in Long Sleepers than in Interrupted and Short Sleepers, but Short Sleepers presented better sleep efficiency than Interrupted Sleepers. Cluster analysis based on objective sleep metrics offers a novel multidimensional approach for the early identification of infants' sleep patterns. Phenotyping sleep patterns is extremely important in identifying the risk for developing neurobehavioral disorders since night wakings and reduced sleep duration in infancy might be predictive of the development of emotional and behavioral problems later in childhood.

The Association Between Sleep Duration and the Risk of Hypertension: A Systematic Review and Meta-analysis of Cohort Studies.

Hypertension onset is linked to sleep, but the precise sleep duration affecting it remains unclear. Our goal is to pinpoint the sleep duration impacting hypertension incidence, offering valuable insights for prevention and management. We conducted a systematic search in PubMed, Embase, Web of Science, CNKI, Cqvip, and Wanfang Database, up to May 30, 2023, focusing on cohort studies examining the association between nighttime sleep duration and hypertension risk in adults aged 18 and above. Two authors independently performed data extraction, quality assessment, and synthesis based on predefined criteria. A random-effects model was used to estimate pooled effect sizes with 95% confidence intervals (CIs). Heterogeneity was quantified using the I2 statistic, with potential sources explored through subgroup and sensitivity analyses to validate the robustness of the results. Out of the 173,734 participants included in the meta-analysis, 41,528 eventually developed hypertension. The analysis revealed a correlation between short sleep duration and increased risk of hypertension: 1.07 (95% CI 1.00-1.14) for those sleeping ≤ 7h, 1.04 (95% CI 1.02-1.07) for 6-7h, and 1.17 (95% CI 1.06-1.28) for < 6h. For women, with sleep duration 6-7 and < 6h, the pooled risk of hypertension incidence was 1.07 (1.02-1.12) and 1.12 (1.06-1.19). In individuals under 60years of age, an elevated risk of hypertension was observed with sleep durations of less than 6h and between 6 and 7h, with pooled risks of 1.24 (95% CI 1.10-1.39) and 1.05 (95% CI 1.00-1.11), respectively. Hypertension is significantly correlated with sleep duration under 7h, especially in women and those under 60, highlighting the importance of sleep management in hypertension prevention and treatment strategies. PROSPERO: CRD42022345513.

Treatment of Restless Legs Syndrome Improves Agitation and Sleep in Persons With Dementia: A Randomized Trial.

Restless legs syndrome (RLS), a common, treatable, sensorimotor disorder of nighttime uncomfortable leg sensations that interfere with sleep, may prompt nighttime agitation in persons with dementia. This randomized trial was double-blind and placebo-controlled. Participants received a Food and Drug Administration-approved drug for RLS, gabapentin enacarbil (GEn) (Horizant) or placebo. Older adults (N= 147) with dementia due to Alzheimer's disease, nighttime agitation, and RLS, residing in long-term care or at home, participated. The primary outcome was change from baseline to 8weeks in nighttime agitation between 5 pm and 7 am on the Cohen-Mansfield Agitation Inventory Index, Direct Observation. Multivariable linear mixed effects regression models based on multiply imputed data were estimated on nighttime agitation and sleep, with treatment group, week, the 2-way interaction of group and week as predictors, and mean arterial pressure as a covariate based on baseline group imbalances. Mean age ± SD was 83.4 ± 9.1years. Most were female (72.0%), White (92.3%), non-Hispanic (84.6%), and lived in nursing homes (76.9%). Nighttime agitation, by group over time, was significant at 8weeks (estimate,-1.67; P= .003) and 2weeks. Total sleep time (actigraphy) by group over time was significant at 8weeks (estimate, 48.45; P= .026). Observed nighttime wake by group over time was significant at 2 (estimate,-12.54; P= .006) and 8weeks (estimate,-11.12; P= .015). The number having ≥1 adverse events was 60 in the GEn group (81.1%) and 50 in the placebo group (68.5%); with 12 serious adverse events in placebo and 10 in the GEn group. The GEn group had a trend toward more falls (P=.066). Our findings suggest a novel approach for nighttime agitation in persons with dementia: assessing for RLS and initiating interventions. Larger and longer trials are needed.

Low-to-Moderate Daytime Physical Activities Predicted Higher-Quality Sleep Among Habitually Active Agropastoralists.

The positive effects of physical activity (PA) on sleep are widely promoted by public health organizations and supported by abundant empirical evidence. Nonetheless, there remains a dearth of studies investigating the association between daytime PA and nighttime sleep among non-urban and nonindustrial populations that habitually engage in PA as part of their subsistence strategy. Here, we examined the bidirectional relationship between PA and sleep. We also looked at age, gender, and occupation-level differences in moderate-to-vigorous-intensity PA (MVPA), low-intensity PA (LPA), and sedentary activity durations among Basotho and Xhoxa agropastoralists residing in rural villages in the Eastern Cape, South Africa. We analyzed activity and sleep data collected from 113 individuals using MotionWatch actigraphy wristwatches across three field seasons (7111 individual days). Percentage daily total MVPA decreased with age, though older participants maintained low activity levels and did not suffer from poorer sleep compared to younger participants. Herders spent more percentage of their day in higher-intensity activity than non-herders. Overall, women had greater daily percentage MVPA and lower percentage sedentary activity than men. Durations of total MVPA and LPA decreased total sleep time (TST) and improved sleep quality (increased sleep efficiency (SE), decreased fragmentation, and decreased percentage wake after sleep onset). Daytime PA measures were not affected by sleep duration or quality from the previous night. Among this group of habitually active agropastoralists, low-to-moderate-intensity PA durations consistently predicted higher sleep quality. Our findings showed that sleep quality was more strongly affected by PA than sleep duration.

Alcohol induces long-lasting sleep deficits in Drosophila via subsets of cholinergic neurons.

Alcohol consumption causes short- and long-term sleep impairments, which persist into recovery from alcohol use disorder (AUD). In humans, sleep quantity and quality are disturbed even after 2weeks of alcohol abstinence in as many as 72% of AUD patients. These sleep deficits are strong predictors of relapse to drinking, but their underlying biological mechanisms are poorly understood, making them difficult to treat in a targeted manner. Here, we took advantage of Drosophila melanogaster's translational relevance for human sleep and alcohol responses to model human alcohol-induced sleep deficits and determine mechanisms of these effects. While low doses of alcohol stimulate the central nervous system (CNS) in flies and in humans, high doses depress the CNS, leading to sedation. After a single, sedating alcohol exposure, flies experienced loss of nighttime sleep, increased time to fall asleep, and reduced sleep quality. These effects lasted for days but eventually recovered. Hyperactivating ethanol exposures failed to induce sleep deficits, even when repeated, suggesting that CNS-depressant effects of sedating ethanol exposures are required for long-lasting sleep deficits. By manipulating activity in neurons producing different neurotransmitters, we determined that reduced cholinergic activity synergized with a sub-sedating ethanol exposure to cause sleep deficits. We then identified subsets of cholinergic neurons mediating these effects, which included mushroom body neurons previously implicated in sleep and alcohol responses. When those neurons were excluded, sleep effects were abrogated. These data suggest that ethanol-induced suppression of cholinergic neurons induces long-lasting sleep deficits, which are conserved from Drosophila to humans.

Behavioral and sociodemographic correlates of sleep duration among children in Samoa.

To describe sleep duration, adherence to sleep recommendations, and behavioral and sociodemographic correlates of sleep among Samoan children. In a longitudinal cohort study of Samoan children aged 2-9years (n=481; 50% female), primary caregivers reported usual number of hours of nighttime sleep during 2015, 2017/2018, and 2019/2020 data collection waves. Associations between behavioral and sociodemographic characteristics and sleep duration were assessed using generalized linear and mixed effect regressions. Average reported hours of nighttime sleep for toddlers (age 2) was 9.7±1.1 (SD); for preschoolers (age 3-5) 9.5±1.0, and for school-age children (age 6-9) 9.4±1.3, with 58% of children meeting sleep recommendations. Living in a lower income household was associated with 30 more minutes of sleep for toddlers (adjusted β:0.56 [95% CI: 0.03, 1.09]) and preschoolers (adjusted β:0.51 [95% CI: 0.17, 0.85]), while higher reported physical activity was associated with longer sleep for school-age children (adjusted β:0.49 [95% CI: 0.08, 0.91]). Preschoolers with a primary caregiver who did not complete high school had shorter sleep (β: -0.80 [95% CI: -1.12, -0.48]). Among school-aged children, shorter sleep was associated with greater total carbohydrate intake (for every 100g/day, β: -0.01 [95% CI: -0.02, 0.01]) and neotraditional dietary pattern adherence (β: -0.27 [95% CI: -0.53, -0.01]). Efforts should be made to encourage adequate sleep among Samoan children. Correlates of sleep were largely consistent with existing literature. Future research should examine additional culturally and contextually-specific risk factors for insufficient sleep in Samoa and consequences for child health.

Associations between sleep opportunity, sleep problems, and social jetlag and toddlers' adiposity: A cross-sectional study.

This study aims to analyze the associations between sleep characteristics, including sleep opportunity, problems and social jetlag, and toddlers' adiposity. It is part of a larger research project involving 344 children (mean±SD age of 23.6±6.3 months). Children's length/height, weight and waist circumference were measured at childcare centers. Body Mass Index (BMI), weight-for-length/height, and waist-to-length/height were calculated and classified according to percentiles, serving as surrogates of adiposity. Sleep problems were evaluated through questionnaire. Sleep opportunity was reported by parents and defined as the difference between bedtime and wake-up time. Social jetlag was calculated based on sleep midpoints. Parental questionnaires provided sociodemographic characteristics. Total energy intake was determined from a two-day dietary record, and motor development was assessed using the Bayley-III scales. Generalized linear models were used in the analysis. We found that nighttime sleep opportunity on weekdays was inversely associated with BMI percentile (B=-5.57, 95% CI -9.79 to -1.35), even with covariates included. Additionally, later bedtime on weekend days were associated with lower weight-for-length/height and waist-to-length/height (B=-4.16, 95% CI -8.01 to -0.30, and B=-10.62, 95% CI -15.38 to -5.87, respectively), even when adjusted for potential confounders. Later bedtime on weekdays was associated with lower waist-to-length/height (B=-8.85, 95% CI -14.95 to -2.74). Social jetlag was associated with lower waist-to-length/height (B=-7.19, 95% CI -13.47 to -0.90). Future research is needed to clarify these associations and to encourage lifestyle-based interventions aimed at optimizing sleep patterns within this age group.

Physical behaviours during pregnancy may alter the association of maternal insulin sensitivity with neonatal adiposity: a prospective pre-birth cohort of mother-child pairs

BackgroundLower maternal insulin sensitivity during pregnancy is associated with greater fetal adiposity. Physical activity can improve insulin sensitivity, but it is not known if physical behaviours influence the known association of maternal insulin sensitivity with offspring adiposity. This study aimed to investigate the moderating impact of physical behaviours on this association.MethodsPregnant women (n = 812) from the Gen3G cohort were recruited during the first trimester of pregnancy and followed until delivery. At the first (V1) and second trimester (V2) hospital visits, Gen3G staff measured anthropometry, and participants reported sleep duration as well as leisure physical activity and sedentary behaviour via lifestyle questionnaires. We used plasma glucose and insulin values from the 75 g oral glucose tolerance test at V2 to calculate insulin sensitivity using the Matsuda index. We recorded birthweight from electronic medical records. Among a subset of neonates (n = 265), trained research staff measured skinfold thickness using a calibrated skinfold caliper following standardized protocols to estimate neonatal adiposity. Linear regression analyses assessed the association of insulin sensitivity with birthweight z-score and sum of neonatal skinfold thickness, adjusting for maternal age, race/ethnicity, gravidity, smoking, with and without adjustment for maternal body mass index at V1. We evaluated moderation by physical activity, sedentary behaviour, or nighttime sleep duration using interaction terms and stratified analyses for the association of maternal insulin sensitivity with offspring birthweight and with offspring adiposity.ResultsLower Matsuda index was associated with higher birthweight z-score (ß±SE= -0.180 ± 0.056, p = 0.001) and with higher sum of skinfold thickness (neonatal adiposity) (ß±SE=-0.877 ± 0.383, p = 0.02) in fully adjusted models. The association between Matsuda index and sum of skinfold thickness was weaker in women with higher levels of physical activity at V2 ([high ≥ 1.26 kcal/kg/day] ß±SE=-0.15 ± 0.65) compared to women with lower levels [low < 1.26 kcal/kg/day] ß±SE=-1.36 ± 0.51, P-interaction = 0.01). We also observed potential interactions of sleep and sedentary behaviour at V2 with Matsuda index for the association with birthweight z-score. We did not observe effect modification by levels of physical behaviours assessed at V1.ConclusionThe association between lower insulin sensitivity and higher neonatal adiposity was attenuated in women with higher physical activity levels in the second trimester, independent of maternal body mass index.

Self-Similarity Analysis of Heartbeat Fluctuations in Sleep Among Female Shift Workers

Cardiovascular signals exhibit self-similarity characteristics, which are influenced by changes in autonomic nervous system (ANS) regulation caused by shift work. This study aims to assess the self-similarity properties of inter-beat interval (IBI) in healthy female shift workers and non-shift workers in different sleep stages to detect alterations in heartbeat fluctuations due to shift work. Short- and long-term self-similarity properties of the IBI signal ([Formula: see text] and [Formula: see text] scaling exponents, respectively) were analyzed using Detrended Fluctuation Analysis. Time and frequency indices were also calculated. In addition, Principal Component Analysis (PCA) was employed to reduce dimensionality and evaluate group separability based on the obtained features. Most indices showed similar values in the different sleep stages for both groups, but [Formula: see text] during light sleep and sympathovagal balance during REM sleep showed a significant decrease in shift workers compared to non-shift workers ([Formula: see text]). In addition, PCA was able to separate shift workers from non-shift workers and differentiate between nighttime and daytime sleep of workers. This analysis aids in identifying cardiovascular impairment associated with shift work and suggests a loss of ANS self-similarity in shift workers, indicating reduced adaptive capacity. Such alterations in ANS behavior could lead to serious health consequences related to cardiovascular disease.

Optimising lighting conditions to enhance seafarer adaptation to the '6-h on/6-h off' shift pattern: a balanced crossover study.

The '6-h on/6-h off' shift pattern could potentially disrupt the physiological rhythms and cognitive performance of seafarers, attributed to its shorter and more frequent shifts. Conversely, light exposure has been demonstrated to enhance cognitive abilities and synchronise physiological processes. Therefore, we studied the fatigue, cognition, sleep and rhythm of seafarers with different shifts to determine how light can benefit their performance. A total of 16 seafarers participated in a 2 × 2 crossover study, which involved two shift types (Morning-Evening and Day-Night) and two lighting conditions (static lighting and dynamic lighting). Sleepiness, cognition and fatigue were assessed every 2 h during '6-h on' period, using the Karolinska Sleepiness Scale, psychomotor vigilance task, critical flicker frequency and visual analogue scale for fatigue. Sleep was monitored during '6-h off' period, core body temperature was continuously tracked for rhythm throughout the shift protocol. For the Day-Night shift, the static mode with stable higher illuminance than dynamic lighting significantly reduced sleepiness (p = 0.01), objective fatigue (p = 0.001), subjective fatigue (fatigue level [p = 0.004] and visual fatigue [p = 0.001]) during the night period, while increasing sleep duration during the day (6:00 a.m. to 12:00 p.m.) and delaying the rhythm. For the Morning-Evening shift, dynamic lighting with lower illuminance significantly increased sleep duration during the night (12:00 a.m. to 6:00 a.m.) without causing a significant difference in performance. Overall, static lighting is more suitable for Day-Night shift seafarers due to lower sleepiness, fatigue and longer daytime sleep duration, while dynamic lighting is more suitable for Morning-Evening shift seafarers due to longer night-time sleep duration. Therefore, different lighting patterns should be adopted for seafarers during different shifts.

U-shaped association between sleep duration and frailty in Chinese older adults: a cross-sectional study.

As the population ages, understanding the association between sleep patterns and physical frailty in older adults is crucial for formulating effective health interventions. This study aimed to explore the relationship among nap time, nighttime sleep duration, and physical frailty in older Chinese individuals; establish recommended sleep times; and provide a scientific and reasonable basis for the prevention and management of frailty in older adults. On the basis of the 2020 China Health and Retirement Longitudinal Study database, demographic information, health data, and lifestyle information of the research subjects were obtained. A total of 5,761 survey participants were included, and logistic regression and restricted cubic splines were used to explore the association between sleep duration and frailty. In our cross-sectional analysis, the duration of napping in older adults did not show a significant correlation with frailty. The optimal nighttime sleep interval for older adults was 7-8 h, and the maximum health benefit was achieved when nighttime sleep reached 7.5 h. Compared with older adults in China who slept 6-8 h at night, those with a sleep duration of <6 h (OR = 1.58, 95% CI: 1.36-1.82) were more likely to be frail. After adjusting for all covariates such as smoking, multimorbidity, self-rated health, social events, education level, and frequency of physical activity, we found no interaction between gender and age concerning sleep duration. The potential correlation between nighttime sleep duration and frailty in older adults is basically U-shaped. Older Chinese adults with a moderate nighttime sleep duration of 7-8 h exhibited the lowest likelihood of frailty than their counterparts. The duration of napping is not related to the likelihood of frailty in older people. Thus, the importance of sufficient nighttime sleep for the health of older adults must be emphasized.

Machine learning algorithms to predict depression in older adults in China: a cross-sectional study.

The 2-fold objective of this research is to investigate machine learning's (ML) predictive value for the incidence of depression among China's older adult population and to determine the noteworthy aspects resulting in depression. This research selected 7,880 older adult people by utilizing data from the 2020 China Health and Retirement Longitudinal Study. Thereafter, the dataset was classified into training and testing sets at a 6:4 ratio. Six ML algorithms, namely, logistic regression, k-nearest neighbors, support vector machine, decision tree, LightGBM, and random forest, were used in constructing a predictive model for depression among the older adult. To compare the differences in the ROC curves of the different models, the Delong test was conducted. Meanwhile, to evaluate the models' performance, this research performed decision curve analysis (DCA). Thereafter, the Shapely Additive exPlanations values were utilized for model interpretation on the bases of the prediction results' substantial contributions. The range of the area under the curve (AUC) of each model's ROC curves was 0.648-0.738, with significant differences (P < 0.01). The DCA results indicate that within various probability thresholds, LightGBM's net benefit was the highest. Self-rated health, nighttime sleep, gender, age, and cognitive function are the five most important characteristics of all models in terms of predicting the occurrence of depression. The occurrence of depression among China's older adult population and the critical factors leading to depression can be predicted and identified, respectively, by ML algorithms.

Private Tutoring, Sleep Time, and Depressive Symptoms Among Adolescent Students in China

The recent increase in mental health problems and private tutoring (also called shadow education) among adolescents has been widely documented. This study relates involvement in private tutoring to depressive symptoms using data from a nationally representative sample of middle school students (grades 7–9, Mage = 13.90, N = 25,862) in China. Results show that greater involvement in tutoring is associated with increased depressive symptoms, and a decrease in nighttime sleep duration plays a mediating role. Grade-specific subsample analyses further show that the mediating role of sleep reduction becomes more pronounced for students in higher grades. These findings highlight the essential role of private tutoring for adolescent sleep and mental health and its variation across the schooling process.

Living in Biological Darkness II: Impact of Winter Habitual Daytime Light on Night-Time Sleep.

Timing and architecture of sleep are co-driven by circadian rhythms modulated by their major Zeitgeber light and darkness. In a natural environment, one is exposed to 3.000 lx (cloudy winter sky) to 100.000 lx (bright sunny sky). The aim of the study was to assess (1) habitual daytime light exposure in urban winter and (2) impact of daytime urban light on objective night-time sleep. Eleven healthy participants (mean age ± SD: 25.4 ± 2.8 years; 6 male) wore eyeglass frames continuously recording daytime illuminance levels vertically to the eye by mounted sensors (range: 1-40.000 lx) during four consecutive days in winter 2008 in Berlin, Germany. In-lab polysomnography was performed over two nights in nine participants. Median light exposure over 4 days was the following: full day 7:00-19:00 h: 23 lx (12-37 lx); morning 7:00-11:00 h: 81 lx (19-201 lx); midday 11:00-15:00 h: 68 lx (19-164 lx); afternoon 15:00-19:00 h: 22 lx (6-58 lx), resulting in only 36 min > 500 lx per day. Timing of daytime light intensity was significantly associated with subsequent sleep: lower midday illuminance with shorter REM latency (Rho = 0.817; p = 0.049) and earlier REM polarity (less prevalence of REM at end-of-sleep; Rho = 0.817; p = 0.049). Humans, living in an urban environment, appear to be exposed to extremely low light levels, which we named as 'Living in Biological Darkness'. Most fascinating, physiology seems to adapt and responds to variation in light intensity on such low levels. Interestingly, the observed changes in sleep architecture with low light levels are reminiscent of those suspected to constitute biological markers of depression some 40-50 years ago.

SLEEP MEASUREMENT TECHNOLOGY IN THE 40 WINKS PRAGMATIC CLINICAL TRIAL: CHALLENGES AND SOLUTIONS

Abstract This presentation describes examples, challenges, and solutions for using technology as part of a pragmatic trial to both deliver a sleep promotion intervention and measure its outcomes. In this trial, target nursing home residents wear an actigraph on their wrist for one week. Actigraphs are a non-invasive way of monitoring activity and rest cycles. One effective and novel application of this technology is use of the actigraphy clinical report. As part of the intervention, the clinical report of the resident’s nighttime sleep, daytime napping, light exposure, and physical activity is shared with the nursing home staff during frontline staff huddles. The frontline staff then use the report to inform and target their sleep promotion interventions, for example, increasing daytime light exposure or activity, and to monitor effectiveness. Use of this technology is not without challenges. We will thus discuss several challenges and their solutions, including identifying the best wrist bands for securing the actigraphs and addressing manufacturer discontinuation of actigraph production and hardware service. We will also describe the trial’s initial pilot that compared the gold standard research actigraph with a less expensive and more readily available consumer-focused device and why we, ultimately, chose to use only the research device.

DAILY ASSOCIATIONS OF ACTIGRAPHIC SLEEP AND NEXT-DAY WORKING MEMORY IN MIDLIFE AND OLDER ADULTS

Abstract This study evaluates the day-to-day associations between actigraphic nighttime sleep and next day working memory in a sample of diverse midlife and older adults. The study used a subsample of the HANDLSleep Study which provided complete information of the variables of interest. Preliminary data from wave 5 (2022-current, n=104, 72% female, 55% Black adults, mean age: 62) were collected via a wrist-worn accelerometer and daily mobile phone cognitive tasks over one week, from which nighttime sleep measures and next-day working memory outcomes were derived. Multilevel linear models tested within-person associations of nightly sleep duration, timing, and quality with next-day mean reaction time calculated from the Multiple Object Tracking (MOT) Task via a mobile device, which evaluates working memory. Analyses were stratified by poverty status (above/below 125% federal poverty line) and adjusted for age, sex, race, WRAT3 literacy scores, average sleep measures, and weekend/weekday. Within individuals who live below the poverty line (n=47), on nights when participants fell asleep earlier (p=.013) and slept longer (p=.021) but had more minutes of wake (p=.0013) and less efficient sleep (p=.018) than their average, next-day mean reaction time was faster. Sleep measures were not associated with next-day working memory for individuals who live equal/above the poverty line. Our results demonstrate that within-person improvements to nightly sleep timing and duration may help next-day reaction time on working memory in adults who live below the poverty line.

TECHNOLOGY FOR SUPPORTING HEALTH AND WELLNESS

Abstract As the population ages, there is a growing need for technology to support the health and wellbeing of older people. However, technology solutions, for them to be successful, need to recognize the needs, preferences, and abilities of older people, and must be evaluated rigorously for efficacy. This talk provides an overview of the potential and pitfalls of using technology to support health and wellness. Hye Soo Lee, PhD, explores the role of technology in supporting Medicare-related decision-making by older adults, highlighting the need for improved training and the consideration of user characteristics to enhance engagement with government-provided digital tools. Paul Freddolino, PhD, MDiv, presents findings from telehealth training sessions with older adults, emphasizing the importance of end-user feedback in refining patient-focused content and increasing patient engagement in healthcare. Justin Lam, BS, discusses the design of age-friendly web interfaces, focusing on optimizing user interaction patterns and enhancing readability to accommodate the nuanced needs of older adults and their care partners. Elena Remillard, M.S., shares insights from deploying ‘Telewellness’ programs, such as Tele Tai Chi, in community settings, identifying barriers and facilitators to their delivery and discussing the potential of different models to increase access to exercise classes for older adults with mobility disabilities. Leo He, BSc, introduces a novel, radio-based, non-contact system for monitoring nighttime vital signs and sleep, offering a passive, cost-effective solution for home-based health monitoring that avoids the physical and cognitive burdens associated with existing technologies, aiming to improve health intervention and quality of life for older adults.

A Pilot Study Using a Smartwatch to Search for Biomarkers of Heart Rate Variability in Active Ulcerative Colitis

Introduction: Autonomic imbalance has been reported to correlate with clinical remission in patients with ulcerative colitis (UC). This study evaluated heart rate variability (HRV), a potential digital biomarker, in patients with active UC using a smartwatch that is easy to handle. Methods: Patients with active UC were recruited for this prospective study. The patients’ HRV was measured via the Fitbit Inspire2™ linked via Bluetooth to their smartphone. HRV during nighttime sleep was obtained from continuous data. Patients were required to input the Simple Clinical Colitis Activity Index (SCCAI) score once daily by the application on their smartphones for 3 months. Results: Nine patients with UC were included. In clinically active disease, SCCAI scores showed a weak inverse relationship with parasympathetic activity, differences of successive R-R pulse intervals (RMSSD) (r = −0.44, p < 0.0001), high frequency (HF) (r = −0.42, p < 0.0001), and total autonomic nervous activity, low frequency (LF) (r = −0.43, p < 0.0001). Receiver operating characteristic analysis indicated that the RMSSD, HF, and LF were significantly higher in patients with active UC. Meanwhile, LF showed the most correlation with severity for bowel urgency scores. Conclusion: Longitudinal nighttime HRV recorded using a smartwatch is associated with disease activity in patients with active UC. In particular, RMSSD and HF, which are indices of the parasympathetic nervous system, have been suggested as potential digital biomarkers for UC. Introduction: Autonomic imbalance has been reported to correlate with clinical remission in patients with ulcerative colitis (UC). This study evaluated heart rate variability (HRV), a potential digital biomarker, in patients with active UC using a smartwatch that is easy to handle. Methods: Patients with active UC were recruited for this prospective study. The patients’ HRV was measured via the Fitbit Inspire2™ linked via Bluetooth to their smartphone. HRV during nighttime sleep was obtained from continuous data. Patients were required to input the Simple Clinical Colitis Activity Index (SCCAI) score once daily by the application on their smartphones for 3 months. Results: Nine patients with UC were included. In clinically active disease, SCCAI scores showed a weak inverse relationship with parasympathetic activity, differences of successive R-R pulse intervals (RMSSD) (r = −0.44, p < 0.0001), high frequency (HF) (r = −0.42, p < 0.0001), and total autonomic nervous activity, low frequency (LF) (r = −0.43, p < 0.0001). Receiver operating characteristic analysis indicated that the RMSSD, HF, and LF were significantly higher in patients with active UC. Meanwhile, LF showed the most correlation with severity for bowel urgency scores. Conclusion: Longitudinal nighttime HRV recorded using a smartwatch is associated with disease activity in patients with active UC. In particular, RMSSD and HF, which are indices of the parasympathetic nervous system, have been suggested as potential digital biomarkers for UC.

Prevalence of cognitive impairment and its related factors among Chinese older adults: an analysis based on the 2018 CHARLS data.

Cognitive impairment is a major public health concern in aging societies. This study aimed to investigate the prevalence of cognitive impairment and its associated factors among Chinese adults aged 60 years and older using data from the 2018 China Health and Retirement Longitudinal Study (CHARLS). Utilizing data from the 2018 wave of CHARLS, we assessed participants' cognitive status using the Mini-Mental State Examination (MMSE), and the influencing factors related to cognitive impairment were analyzed by using the chi-square test and multifactor logistic regression. The prevalence of cognitive impairment was stratified by gender, education level, residence, marital status, daytime napping, and nighttime sleep duration, and the trend of cognitive impairment prevalence with age was observed. 9,804 participants were finally included in the study and the overall prevalence of cognitive impairment was 44.04% (95%CI, 43.02-45.06%). The prevalence was significantly higher in females (50.8%) than males (37.1%), and increased with age, from 41.5% in those aged 60-64 years to 57.7% in those aged ≥75 years. Lower educational level, rural residence, and being divorced/ widowed/unmarried were associated with a higher prevalence of cognitive impairment (all p < 0.001). Multifactor logistic regression indicated that older age (OR = 1.51, 95%CI, 1.33-1.73 for ≥75 vs. 60-64 years), female gender (OR = 1.54, 95%CI, 1.35-1.77), higher education (OR = 0.46, 95%CI, 0.42-0.51 for primary school and below vs. illiteracy), rural areas (OR = 2.35, 95%CI, 2.07-2.65 for village vs. the center of city/town), divorced/ widowed/unmarried status (OR = 1.40, 95%CI, 1.25-1.57) and participation in physical activity (OR = 0.80, 95%CI, 0.73-0.87) were significantly associated with cognitive impairment. Cognitive impairment is highly prevalent among older adults in China with substantial demographic disparities. Targeted interventions and public health strategies are needed to promote cognitive health in this rapidly aging population.