Actigraphy Monitoring Research Articles

A - 91 Nocturnal Motor Activity and Wake after Sleep Onset and Neuropsychological Health in Veterans with Gulf War Illness

Abstract Objective To examine the association between actigraphy-based sleep parameters and neuropsychological health in Veterans with Gulf War Illness (GWI). Methods Objective sleep data was obtained from 85 GW Veterans (Mage = 54.2, 79% Male) using an actigraphy monitor (Phillips Respironics Actiwatch-2) worn for 24 hours/day for seven consecutive days. Actigraphy data was manually scored to define time in bed (TIB), and total sleep time (TST), wake after sleep onset (WASO), number of awakenings (NWAK), and motor activity counts (MAC) during sleep were derived using the device software. Participants completed a battery of questionnaires: Patient Health Questionnaire (PHQ-9), Posttraumatic Symptom Checklist (PCL-5), and Pittsburgh Sleep Quality Index (PSQI). Cognitive function was assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Correlation analysis was conducted to discover associations between sleep parameters, self-reported measures, and cognitive function. Results MAC was positively correlated with elevated scores on PSQI (r = 0.35, p < 0.01), PHQ-9 (r = 0.26, p < 0.05), and PCL-5 (r = 0.26, p < 0.05), and negatively correlated with RBANS Total Index score (r = −0.27, p < 0.05). WASO was also positively correlated with PSQI scores (r = 0.29, p < 0.01). TIB and TST were positively correlated with age (r = 0.25, r = 0.28; all p < 0.05). Conclusion Objective parameters of disrupted sleep – nocturnal MAC and WASO – were associated with greater self-reported sleep disturbance. MAC was additionally correlated with increased self-reported symptoms of depression and PTSD, as well as lower performance on a measure of objective cognitive function. This study identifies aspects of sleep disruption as potential sleep intervention targets related to both mood and cognitive symptoms.

Rest-Activity Rhythm Phenotypes in Adults with Epilepsy and Intellectual Disability.

Sleep and rest-activity rhythms (RARs) are perturbed in many forms of neuropsychiatric illness. In this study, we applied wrist actigraphy to describe the extent of RAR perturbations in adults with epilepsy and intellectual disability ("E+ID"), using a cross-sectional case-control design. We examined whether RAR phenotypes correlated with epilepsy severity, deficits in adaptive function and/or comorbid psychopathology. Primary caregivers of E+ID adults provided informed consent during routine ambulatory clinic visits and were asked to complete standardized surveys of overall epilepsy severity (GASE, Global Assessment of Severity of Epilepsy), adaptive function (ABAS-3, Adaptive Behavior Assessment System-3) and psychopathology (ABCL, Adult Behavior Checklist). Caregivers were also asked to ensure that subjects wore an Actiwatch-2 device continuously on their nondominant wrist for at least ten days. From recorded actograms, we calculated RAR amplitude, acrophase, robustness, intradaily variability (IV), interdaily stability (IS) and estimates of sleep quantity and timing. We compared these RAR metrics against those from (i) a previously published cohort of adults with epilepsy without ID (E-ID), and (ii) a cohort of age- and sex-matched intellectually able subjects measured within the Study of Latinos (SOL) Ancillary actigraphy study (SOL). Within E+ID subjects, we applied k-means analysis to divide subjects into three actigraphically distinct clusters. 46 E+ID subjects (median age 26 [20-68], 47% female) provided a median recording duration of 11 days [range 6-27]. Surveys reflected low to extremely low levels of adaptive function (ABAS3 General Adaptive Composite score: median 50 [49-75]), and low/subclinical levels of psychopathology (ABCL total score: median 54.5 [25-67]). Compared with E-ID (n=57) and SOL (n=156) cohorts, E+ID subjects displayed significantly lower RAR amplitude, robustness and IS, with significantly higher IV and total daily sleep. K-means clustering of E+ID subjects recognized an intermediate cluster "B", with RAR values indistinguishable to E-ID. Cluster "A" subjects displayed pronounced hypoactivity and hypersomnia with high rates of rhythm fragmentation, while cluster "C" subjects featured hyper-robust and high amplitude RARs. All three clusters were similar in age, body mass index, antiseizure medication (ASM) polytherapy, ABAS3 and ABCL scores. We qualitatively describe RAR examples from all three clusters. We show that adults with epilepsy and intellectual disability display a wide spectrum of RAR phenotypes that do not neatly correlate with measures of adaptive function or epilepsy severity. Prospective studies are necessary to determine whether continuous actigraphic monitoring can sensitively capture changes in chronobiological health that may arise with disease progression, iatrogenesis (e.g., ASM toxicity) or acute health deteriorations (e.g., seizure exacerbation, pneumonia). Similar long-term data is necessary to recognize whether behavioral interventions targeted to 'normalize' RARs may promote improvements in adaptive function and therapy engagement.

Relationship Between Patient-reported Outcome Measures and Accelerometer-measured Physical Activity and Sleep in Patients With Postherpetic Neuralgia.

Available treatment for chronic neuropathic pain is still limited, and the positive effects are modest. Thus, clinicians aim to improve activity and quality of life despite pain. The objective monitoring of activity is attracting attention in chronic pain assessments. Therefore, we objectively evaluated daytime activity and sleep in patients with postherpetic neuralgia (PHN), using actigraphy to determine risk factors for decreased activity. Participants with PHN wore an actigraph (a wristwatch-like accelerometer) on the nondominant hand. The actigraph measured day-time activity and sleep, which were compared with participant-reported subjective pain and sleep assessments. Fifty-four individuals with PHN who visited our outpatient clinic completed questionnaires and a week of actigraph monitoring. Subjective scores of pain intensity, neuropathic pain, disability in daily life, pain-catastrophizing thoughts, and insomnia were all well correlated. However, the actigraph-monitored activity levels, using 2 equations, and sleep quality were not associated with any pain or sleep-related subjective scores. The discrepancy between the subjective and objective scores in this study may be due to (1) features of PHN, an archetype of peripheral neuropathic pain affecting no motor nerves, (2) actigraph measurement limitations regarding the sedentary life of the elderly, or (3) activity misperception, a new proposition explaining the discrepancy between subjective and objective measures of activity, similar to the sleep state misperception. In patients with PHN, high pain intensity may be reported in those with highly maintained activity, in which treatment must be selected cautiously to prevent interruption of their physical abilities.

Agreement of activity monitors for assessment of patients with sub-acute stroke in an inpatient rehabilitation facility

Purpose Determine the level of agreement of three activity monitors compared with the gold standard (video review) on the activity level of patients with stroke. Methods A prospective, observational, agreement study was performed on 47 individuals with sub-acute stroke in an inpatient rehabilitation facility. Data was collected during one physical therapy session. Individuals wore three device types; Actigraph (AG), Activpal (AP), and stepwatch activity monitor (SAM). Variables assessed were step counts for each limb (hemiparetic and non-hemiparetic) and percent time standing and other. Analysis Results from the activity monitors were compared to the video review and assessed for agreement using the intraclass correlation coefficient (ICC) and accuracy of mean difference from video observation. Results The step counts with the SAM on the non-hemiparetic limb had the highest ICC for step counts (ICC = 0.98, p < 0.001) and were overestimated with 21% accuracy. The SAM on the hemiparetic limb had 9.7% accuracy (ICC = 0.92, p < 0.001). For percent standing time all devices overestimated with poor reliability. For percent other activity time, the AP had the best accuracy and underestimated for both the hemiparetic limb (9.9% accuracy; ICC = 0.90, p < 0.001) and non-hemiparetic limb (8.3% accuracy; ICC = 0.84, p < 0.001). Conclusions The use of multiple devices may be warranted to capture an accurate understanding of activity levels in this population of individuals with sub-acute stroke. There are concerns with all monitors and clinicians and researchers should be aware of what measures they are wanting to understand about their population.

Characterization of sleep disturbance in established rheumatoid arthritis patients: exploring the relationship with central nervous system pain regulation

BackgroundTo characterize sleep disturbance in patients with established rheumatoid arthritis (RA) and explore the relationship between sleep and mechanisms of central nervous system pain regulation.MethodsForty-eight RA participants completed wrist-worn actigraphy monitoring and daily sleep diaries for 14 days to assess sleep-wake parameters. Participants underwent quantitative sensory testing to assess pressure pain thresholds, temporal summation, and conditioned pain modulation. Data were analyzed using descriptive statistics, Spearman’s correlation, and multivariable median regression analyses.ResultsMedian actigraphy and sleep diary derived sleep duration was 7.6 h (interquartile range (IQR) 7.0, 8.2) and 7.1 h (IQR 6.7, 7.6), respectively. Actigraphy based sleep fragmentation (rho = 0.34), wake after sleep onset (rho = 0.36), and sleep efficiency (rho = -0.32) were each related to higher temporal summation values in unadjusted analyses, but these relationships did not persist after controlling for age, body mass index, disease duration, and swollen joint count. No significant relationships were observed between sleep with pressure pain thresholds and conditioned pain modulation.ConclusionActigraphy and sleep diary monitoring are well tolerated in established RA patients. Future investigations should include both subjective and objective assessments, as they may provide information relating to different components and mechanisms.

Actigraphy-based sleep and muscle sympathetic nerve activity in humans.

Short and insufficient sleep are prevalent and associated with cardiovascular disease, with the sympathetic nervous system as a suspected mediator. The purpose of the present study was to investigate the association between objective, actigraphy-based total sleep time (TST), sleep efficiency (SE), and cardiovascular and sympathetic regulation in healthy adults. We hypothesized that short TST and low SE would be associated with elevated resting blood pressure, heart rate (HR), and muscle sympathetic nerve activity (MSNA). Participants included 94 individuals [46 males, 48 females, age: 30 ± 15 yr, body mass index (BMI): 26 ± 4 kg/m2]. All participants underwent at least 7 days of at-home, wristwatch actigraphy monitoring (avg: 10 ± 3 days). Seated blood pressures were assessed using brachial blood pressure measurements, followed by a 10-minute supine autonomic testing session consisting of continuous HR (electrocardiogram), beat-by-beat blood pressure (finger plethysmograph), and MSNA (microneurography) monitoring. Partial correlations were used to determine the relationship between sleep and cardiovascular parameters while accounting for the influence of age, sex, and BMI. TST was not associated with MAP (R = -0.105, P = 0.321), HR (R = 0.093, P = 0.383), or MSNA burst frequency (BF; R = -0.168, P = 0.112) and burst incidence (BI; R = -0.162, P = 0.124). Similarly, SE was not associated with MAP (R = -0.088, P = 0.408), HR (R = -0.118, P = 0.263), MSNA BF (R = 0.038, P = 0.723), or MSNA BI (R = 0.079, P = 0.459). In contrast to recent preliminary findings, our results do not support a significant association between actigraphy-based sleep duration or efficiency and measures of resting blood pressure, heart rate, and MSNA.NEW & NOTEWORTHY The present study investigated the independent association between actigraphy-based sleep duration, efficiency, and measures of blood pressure, heart rate, and muscle sympathetic nerve activity (MSNA) in adult males and females. Contrary to our hypothesis, the findings do not support an independent association between habitual sleep and cardiovascular or sympathetic neural activity. However, these findings do not preclude a potential association between these parameters in populations with sleep disorders and/or cardiovascular disease.

Physical Activity Influences the Relationship between Objectively Measured Hot Flashes and Endothelial Function in Perimenopausal Women

Hot flashes (HF) are disruptive symptoms experienced by approximately 80% of women undergoing menopause. The transition to menopause is associated with increases in CVD risk factors. The frequency and severity of HF have been associated with poorer cardiovascular health but most of these studies have quantified HF by self-report and have not considered physical activity (PA), known for its cardiovascular benefits. The association between HFs and CVD risk may be through their effect on endothelial health. The objective of this study was to evaluate the relationship between objectively measured HF and endothelial function and determine the effect of physical activity on the relationship in healthy perimenopausal women. We hypothesized that more HF would be associated with lower endothelial function and PA would influence this relationship. Healthy perimenopausal women (n=52, age 43-54) were included in this analysis. Perimenopause was defined as ≥7d difference in the length of consecutive cycles to &lt;12 months of amenorrhea. Hot flashes were measured objectively using sternal skin conductance for 24 hours. The number of HF experienced and HF rate (normalized to actual wear time) were quantified. Endothelial function was assessed with measures of brachial artery flow mediated dilation (FMD, %) on the non-dominant arm. Moderate to vigorous physical activity (MVPA) was assessed with 7-days of actigraphy monitoring on the non-dominant wrist. The R package GGIR and Hildebrand (2016) cut points were used to quantify PA intensity and reported as sum of the average minutes of moderate and vigorous physical activity per day. Pearson correlations and multiple regression analyses were used to evaluate relationships between variables. Data met all assumptions for statistical tests. Modeling was performed to evaluate whether HFs were predictors of the main outcome of FMD (R version 4.2.3 and RStudio version 2023.06.2+561). Age and BMI were included in all models. Lower FMD was significantly correlated with a higher objective HF rate ( r (52) =-0.27, p=0.05). Objective HF rate predicted FMD (β=-3.91, p=0.04) when controlling for age and BMI (adj R2=0.100, F(3,48) =2.892, p=.05). When MVPA was added to the model, MVPA alone was not a significant predictor but the interaction between MVPA and HF was (β=0.12, p=0.04; adj R2=0.147, F(5,46) =2.761, p&lt;0.03). This interaction was such that higher levels of MVPA were related to a less strongly negative relationship between objective HF rate and FMD. A simple slopes analysis found that the HF rate effect at one SD below the mean MVPA was significantly negative, (β=-8.64, p=0.004), whereas the HF rate effect at one SD above the mean MVPA was not significant, (β=0.18, p=0.95). These data provide strong evidence that support the hypothesis that a greater number of objectively-assessed hot flashes is associated with lower endothelial function in perimenopausal women and that higher amount of physical activity serves as a buffer against the negative relation between hot flashes and FMD. NIH NHLBI R15 Grant 1R15HL145650-01A1 (Witkowski); Smith College McKinley s Honors Fellowship (Tha Ra Wun); Smith College STRIDE (Buszkiewicz). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Objective Assessment of Physical Activity at Home Using a Novel Floor-Vibration Monitoring System: Validation and Comparison With Wearable Activity Trackers and Indirect Calorimetry Measurements.

The self-monitoring of physical activity is an effective strategy for promoting active lifestyles. However, accurately assessing physical activity remains challenging in certain situations. This study evaluates a novel floor-vibration monitoring system to quantify housework-related physical activity. This study aims to assess the validity of step-count and physical behavior intensity predictions of a novel floor-vibration monitoring system in comparison with the actual number of steps and indirect calorimetry measurements. The accuracy of the predictions is also compared with that of research-grade devices (ActiGraph GT9X). The Ocha-House, located in Tokyo, serves as an independent experimental facility equipped with high-sensitivity accelerometers installed on the floor to monitor vibrations. Dedicated data processing software was developed to analyze floor-vibration signals and calculate 3 quantitative indices: floor-vibration quantity, step count, and moving distance. In total, 10 participants performed 4 different housework-related activities, wearing ActiGraph GT9X monitors on both the waist and wrist for 6 minutes each. Concurrently, floor-vibration data were collected, and the energy expenditure was measured using the Douglas bag method to determine the actual intensity of activities. Significant correlations (P<.001) were found between the quantity of floor vibrations, the estimated step count, the estimated moving distance, and the actual activity intensities. The step-count parameter extracted from the floor-vibration signal emerged as the most robust predictor (r2=0.82; P<.001). Multiple regression models incorporating several floor-vibration-extracted parameters showed a strong association with actual activity intensities (r2=0.88; P<.001). Both the step-count and intensity predictions made by the floor-vibration monitoring system exhibited greater accuracy than those of the ActiGraph monitor. Floor-vibration monitoring systems seem able to produce valid quantitative assessments of physical activity for selected housework-related activities. In the future, connected smart home systems that integrate this type of technology could be used to perform continuous and accurate evaluations of physical behaviors throughout the day.

The use of actigraphy to objectively define motion and function before and after shoulder arthroplasty

IntroductionActigraphy is a quantitative means of measuring activity data that has proven viable in post-surgery recovery analysis for arthroplasties in lower extremities, but scant literature has been published on the utilization actigraphy to evaluate shoulder motion and function before and after shoulder arthroplasty. The purpose of this prospective cohort study is to identify if actigraphy can serve as a valid means for objective evaluation of shoulder function and motion before and after shoulder arthroplasty. Secondarily, the data collected by the actigraphy can be analyzed with standard patient-reported outcomes to report correlations between the subjective and objective methods used in this study. Materials and methodsSixty-four subjects wore an actigraphy device for one day at pre-op, six, twelve and twenty-four weeks. In addition, subjects completed three patient-reported outcome surveys at each time-point. Student t-tests were used to compare percent activity preoperatively with 24-weeks and to compare PROs preoperatively with 24-week results; categorical variables were compared with one-way ANOVAs. ResultsAll Patient reported outcome scores significantly improved following arthroplasty (p-value<0.001). The percent of physical activity was highly correlated with vector magnitude (p-value<0.001), but neither percent activity or the vector magnitude were correlated with any of the PROs: UCLA Pain p-value = 0.656, SANE p-value = 0.328, UCLA Function p-value = 0.532. ConclusionsActigraphy results from this study mirror findings in previous literature utilizing the technology in similar manners and demonstrate its potential for motion and function analysis before and after total shoulder arthroplasties. Despite both being suitable methods independently for the evaluation of shoulder function, there was no significant correlation between standard actigraphy measurements and PROs at 24-weeks. Future research to determine clinical utility and an overall broader scope for actigraphy monitoring could benefit from improved technology, such as increased battery life for prolonged durations of data collection during observation periods.

Alteration of circadian sleep-wake rhythm and salivary melatonin secretion in idiopathic/isolated REM sleep behavior disorder: Preliminary evidence

Objective/BackgroundIdiopathic/isolated REM sleep behavior disorder (iRBD) is widely regarded as an early sign of neurodegeneration leading to synucleinopathies. While circadian rhythm alterations in iRBD have been preliminarily demonstrated, evidence on melatonin secretion patterns in this clinical condition is limited. To address this knowledge gap, this exploratory study aimed to integrate salivary melatonin measurement with actigraphic monitoring in individuals with iRBD and age-matched healthy controls (HC) under real-life conditions. MethodsParticipants diagnosed with iRBD and HC underwent clinical evaluation and wore an actigraph for seven days and nights. Salivary melatonin concentrations were measured at five time points during the last night of recording. Comparative analyses were conducted on clinical data, actigraphic parameters, and melatonin levels between the two groups. ResultsiRBD participants (n = 18) showed greater motor (p < 0.01) and non-motor symptoms (p < 0.001), alongside disruptions in circadian sleep-wake rhythm compared to HC (n = 10). Specifically, actigraphy revealed a delayed central phase measurement (p < 0.05), reduced activity during the most active hours (p < 0.001), and decreased relative amplitude (p < 0.05). Total salivary melatonin concentration was significantly lower in iRBD (p < 0.05), with a slight but non-significant phase delay in dim light melatonin onset. ConclusionsThis exploratory study highlights a dysregulation of circadian sleep-wake rhythm coupled with reduced melatonin secretion in iRBD. Future research could add to these preliminary findings to evaluate novel treatment approaches to regulate the sleep-wake cycle and elucidate the implications of circadian dysregulation in the conversion from iRBD to neurodegeneration.

Objective and subjective sleep patterns and biomarkers of stress among women with a history of sexual abuse in childhood.

Childhood sexual abuse (CSA) is associated with posttraumatic stress symptoms (PTSSs) and sleep disturbance into adulthood. The latter is thought to emerge from dysregulation in biobehavioral systems, including nighttime hyperarousal; however, studies investigating specific mechanisms to explain these long-term sleep problems are limited. The present study examined presleep arousal, fear of sleep, and the cortisol awakening response (CAR) as putative mediators between PTSS and sleep disturbance in women with a history of CSA. N = 64 cis-gendered women with a self-reported history of CSA completed a baseline diagnostic interview, self-reported mental health and sleep measures, 7 days of actigraphy monitoring with concurrent sleep diary, and 2 days of saliva sampling. PTSSs were not significantly associated with actigraphy-estimated sleep variables but were positively associated with self-reported sleep onset latency (SOL) and negatively associated with self-reported sleep quality. Similarly, PTSSs were not significantly associated with CAR but were associated with higher presleep arousal and fear of sleep ratings. Mediational models identified greater presleep cognitive arousal to partially explain the PTSS-SOL relationship. Specific features of CSA (i.e., age at time of abuse, location of abuse, relationship to the perpetrator) did not moderate this association. Findings suggest that targeting maladaptive cognitions (e.g., worries, rumination) that occur during the presleep period may be a potential intervention target in mitigating sleep disturbance and PTSSs in this population. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

A 90- followed by a 30-min nap reduces fatigue whereas a 30- followed by a 90-min nap maintains cognitive performance in night work: A randomized crossover-pilot study

ObjectiveTo investigate the effects of combinations of brief naps (a 90- followed by a 30-min nap vs. a 30- followed by a 90-min nap) on sleep inertia, reducing sleepiness and fatigue, and maintaining performance during night hours. MethodsThis randomized, comparative, repeated-measure, cross-over study investigated subjective and cognitive performance in 12 healthy females, evaluated in three experimental nap conditions: 1) from 22:30 to 00:00 and 02:30 to 03:00 (Pre90-NAP group), 2) from 23:30 to 00:00 and 02:30 to 04:00 (Pre30-NAP) group, and 3) no naps (NO-NAP group). Participants’ body temperature, psychomotor vigilance task (PVT) and Uchida-Kraepelin test (UKT) scores, and subjective feelings of drowsiness and fatigue were evaluated. Sleep state was determined by an actigraphy monitoring device worn by participants. ResultsRegardless of timing, both 90-min naps were associated with sleep inertia, and both 30-min naps with minimal sleep inertia. Reaction times were shorter and fewer errors were committed at 2 h post-nap in the Pre30-NAP and Pre90-NAP groups compared with those at the same time in the NO-NAP group. Adding a 90-min nap to a 30-min nap reduced subjective fatigue and shortened reaction times, and adding a 30-min nap to a 90-min nap was effective in maintaining performance, suggesting a synergistic effect. ConclusionsTaking two naps during a night work can mitigate sleepiness and fatigue, and maintain performance. A 90- followed by a 30-min nap reduced fatigue and reaction time, and a 30- followed by a 90-min nap maintained cognitive performance in the early morning.

Feasibility and acceptability of collecting biobehavioral data from Latinx transgender and nonbinary people

Background Latinx transgender and nonbinary (TGNB) people are at high risk of poor health compared to cisgender (i.e., non-TGNB) people. Most studies about the health of Latinx TGNB people have collected self-reported data. There is an urgent need for inclusion of biobehavioral measures to better understand and target the underlying mechanisms of health disparities among Latinx TGNB people. We conducted the first study to assess the feasibility and acceptability of collecting biobehavioral data that we are aware of in this population. Methods Participants were recruited from an existing longitudinal study of TGNB individuals and through outreach to the community. Data collection involved structured surveys, saliva samples, actigraphy, sleep dairies, and blood pressure monitoring. We administered a survey with Likert scale items and open-ended questions to assess the acceptability of our study procedures. Results The sample consisted of 41 Latinx TGNB adults with a mean age of 35.7 (+/− 11.9) years. The majority of participants completed all phases of data collection, demonstrating feasibility of study procedures. Acceptability was overall good, but there were a few exceptions; some participants disliked ambulatory blood pressure monitoring or saliva collection. The open-ended responses on the acceptability survey organized around each aspect of the data collection procedures, and the following additional categories were derived: 1) perceived benefits of participating in research, 2) interest in receiving individual data, and 3) the importance of TGNB cultural awareness for study staff. Conclusions This study is one of the first to demonstrate the feasibility and acceptability of collecting biobehavioral data with Latinx TGNB people. Biobehavioral research can help to illuminate mechanisms underlying the substantial health disparities experienced by this multiply minoritized group. Future research with this population should consider augmenting self-reported data by including biobehavioral measures relevant for the research question.

Exploring the Association Between Physical Activity and Cognitive Function Among People Living with Dementia.

Physical activity preserves cognitive function in people without dementia, but the relationship between physical activity and cognitive domains among people living with dementia is unclear. The objective of this study was to explore the association between physical activity and cognition domains among people living with dementia. Participants living with dementia in residential care facilities (complete case analysis: n = 24/42) completed a battery of cognitive tests (global cognition: Montreal Cognitive Assessment; executive function: Trail-Making Test, Digit Span Forward Test; perception and orientation: Benton Judgement of Line Orientation Test; language: Boston Naming Test; learning and memory: Rey Auditory Verbal Learning Test; complex attention: Digit Symbol Substitution Test). Participants wore an actigraphy monitor on their non-dominant wrist over seven days. We conducted a linear regression for total physical activity (independent variable) with race (white/black), fall risk (Morse Fall Scale), and the number of comorbidities (Functional Comorbidities Index) as covariates, and cognitive tests as variables of interest. Participants were primarily male (75%), white (87.5%), and 50%had unspecified dementia (Alzheimer's disease: 33%). Greater physical activity was associated with poorer global cognition, better executive function, and better learning and memory (ps < 0.05). Physical activity was not related to visuospatial perception, language, or complex attention. Physical activity may preserve executive function and learning and memory among people living with dementia. Wandering is more common in later stages of dementia, which may explain greater physical activity observed with lower global cognition. Regularly assessing physical activity may be useful in screening and monitoring cognitive changes.

Reallocating time between device-measured 24-hour activities and cardiovascular risk in Asian American immigrant women: An isotemporal substitution model.

The 24-hour day consists of physical activity (PA), sedentary behavior, and sleep, and changing the time spent on one activity affects the others. Little is known about the impact of such changes on cardiovascular risk, particularly in Asian American immigrant (AAI) women, who not only have a higher cardiovascular risk but also place greater cultural value on family and domestic responsibilities compared to other racial/ethnic groups. The purpose of this study was to evaluate the effects of reallocating 30 minutes of each 24-hour activity component for another on BMI, waist circumference, and blood pressure in AAI women. Seventy-five AAI women completed 7 days of hip and wrist actigraphy monitoring and were included in the analysis (age = 61.5±8.0 years, BMI = 25.5±3.6 kg/m2, waist circumference = 85.9±10.2 cm). Sleep was identified from wrist actigraphy data, and moderate-to-vigorous PA (MVPA), light PA, and sedentary behavior identified from hip actigraphy data. On average, the women spent 0.5 hours in MVPA, 6.2 hours in light PA, 10 hours in sedentary activities, and 5.3 hours sleeping within a 24-hour day. According to the isotemporal substitution models, replacing 30 minutes of sedentary behavior with MVPA reduced BMI by 1.4 kg/m2 and waist circumference by 4.0 cm. Replacing that same sedentary time with sleep reduced BMI by 0.5 kg/m2 and waist circumference by 1.4 cm. Replacing 30 minutes of light PA with MVPA decreased BMI by 1.6 kg/m2 and waist circumference by 4.3 cm. Replacing 30 minutes of light PA with sleep also reduced BMI by 0.8 kg/m2 and waist circumference by 1.7 cm. However, none of the behavioral substitutions affected blood pressure. Considering AAI women's short sleep duration, replacing their sedentary time with sleep might be a feasible strategy to reduce their BMI and waist circumference.

Evaluation of cognitive and psychomotor faculties in relation to mood-related symptoms under the conditions of sleep deprivation.

Deprivation of sleep (DS) has been associated with changes in mood and cognitive function, rapidly but transiently improving the severity of depression symptoms. However, it remains unclear whether there are differences in performance between DS responders and non-responders. The relationship between DS, mood, cognitive, and psychomotor function is also poorly understood. Participants (n = 77) underwent a baseline assessment of sleep under the control of polysomnography (PSG). Later they were subjected to DS with actigraphy monitoring. Evaluation of mood as well as completing a battery of tests assessing cognitive functions and eye-hand coordination was conducted four times, pre/post PSG and DS. Participants were further divided into respondents (RE, n = 48) and non-respondents (NR, n = 29) depending on alleviation of depression symptoms severity following DS. All participants exhibited increased response speed to visual triggers after DS compared to baseline (p = 0.024). Psychomotor vigilance test (PVT) results remained intact in the RE, whereas it was increased in the NR (p = 0.008). Exposure time in the eye-hand coordination test improved in both groups, but total error duration was reduced only in RE individuals (p < 0.001, p = 0.009 for RE and NR, respectively). All subjects were more proficient at trail-making test (p ≤ 0.001 for Part 1 and 2 in all, NR, RE). Stroop test also improved regardless of mood changes after DS (p = 0.007, p = 0.008 for Part 1 and 2, respectively); cognitive interference remained at a similar level within groups (p = 0.059, p = 0.057 for NR and RE, respectively). A positive correlation was observed between the difference in PSG morning/DS morning depression severity and vigilance (R = 0.37, p = 0.001, R = 0.33, p = 0.005, for error duration eye-hand coordination test and PVT total average score, respectively). RE tend to maintain or improve cognitive function after DS, oppositely to NR. Vigilance in particular might be tightly associated with changes in depression symptoms after DS. Future studies should examine the biological basis behind the response to sleep loss.

THE RELATIONSHIP BETWEEN SEDENTARY BEHAVIOR AND COGNITIVE DOMAINS AMONG PEOPLE LIVING WITH DEMENTIA

Abstract Greater sedentary behavior negatively impacts cognition among older adults without dementia; however, the relationship between sedentary behavior and cognitive domains among people living with dementia (PWD) is unclear. Our aim was to explore the association between sedentary behavior and cognitive domains in PWD in residential care facilities. The testing took place at one nursing home (n=15/23), one memory care unit (n=4/23), and one assisted living facility (n=4/23). Participants completed a battery of cognitive tests (global cognition: Montreal Cognitive Assessment; executive function: Trail Making test, Digit Span Backwards Test; perception and orientation: Benton Judgment of Line Orientation Test; language: Boston Naming Test; learning and memory: Rey Auditory Verbal Learning Test; complex attention: Digit Symbol Substitution Test). We used the Morse Fall Scale to measure fall risk. Participants wore an actigraphy monitor on their wrist over seven days to measure sedentary behavior. Most participants were male (74%), white (87%), and had unspecified dementia (48%). Participants were sedentary for 8.0±2.7 hours/day. The regression model for sedentary behavior was significant (R2=0.82, F(10, 12)=5.39, RMSE=92.47, p&amp;lt; 0.05). Greater sedentary behavior was associated with poorer language function (β=-0.82, p=0.02), poorer learning and memory (β=-0.82, p=0.002), and greater fall risk (β=-0.43, p=0.03). Sedentary behavior was not associated with the other cognitive domains. Greater sedentary behavior may indicate a decline in language function, learning and memory, and increase fall risk in PWD. Sedentary behavior should be considered in routine assessments, as it may play an important role in monitoring cognitive decline in PWD in residential care facilities.

INVESTIGATING THE RELATIONSHIP BETWEEN HABITUAL ACTIVITY AND COGNITIVE DOMAINS AMONG PEOPLE LIVING WITH DEMENTIA

Abstract Habitual activity preserves cognitive function in people without dementia, but the relationship between habitual activity and cognitive domains among people living with dementia is unclear. The purpose of this study was to explore the association between habitual activity and cognition domains among people living with dementia. Participants living with dementia in residential care facilities (complete case analysis: n=24/42) completed a battery of cognitive tests (global cognition: Montreal Cognitive Assessment; executive function: Trail-Making Test, Digit Span Forward Test; perception and orientation: Benton Judgement of Line Orientation Test; language: Boston Naming Test; learning and memory: Rey Auditory Verbal Learning Test; complex attention: Digit Symbol Substitution Test). Participants wore an actigraphy monitor on their non-dominant wrist over seven days. We conducted a linear regression for total habitual activity (independent variable) with race (white/black), fall risk (Morse Fall Scale), and the number of comorbidities (Functional Comorbidities Index) as covariates, and cognitive tests as variables of interest. Participants were primarily male (75%), white (87.5%), and 50% had unspecified dementia (Alzheimer’s disease: 33%). Greater habitual activity was associated with poorer global cognition, better executive function, and better learning and memory (ps&amp;lt; 0.05). Habitual activity was not related to visuospatial perception, language, or complex attention. Habitual activity may preserve executive function and learning and memory among people living with dementia. Wandering is more common in later stages of dementia, which may explain greater habitual activity observed with lower global cognition. Regularly assessing habitual activity may be useful in screening and monitoring cognitive changes.

Children with Autism Spectrum Disorder Exhibit Elevated Physical Activity and Reduced Sedentary Behavior.

According to previous research, individuals with autism spectrum disorder (ASD) have lower levels of physical activity than their typically developed (TD) counterparts. There have been conflicting reports about physical activity (PA) levels in people with ASD. Given the conflicting evidence, further investigation is required. We believe that evaluating PA in individuals with ASD is critical in order to offer PA intervention plans aiming at increasing their health-related physical fitness on a daily, systematic, and individualized basis. In the current study, an ActiGraph monitor (GT3X+) was used to accurately measure PA and sedentary activity in 21 children with autism aged 6.43 ± 2.29 years and 30 TD children aged 7.2 ± 3.14 years. Our data indicated that while the light and moderate activity counts were not significantly different between the two groups, the vigorous activity was significantly higher in ASD compared to TD. This finding was attributed to ASD characteristic stereotypy and self-stimulating behaviors. The significantly higher vigorous PA is discussed in relation to altered neurochemistry, oxidative stress, and neuroinflammation as etiological mechanisms in ASD. This research provides a better understanding of the status of PA participation in individuals with ASD.

90 Association Between Sedentary-To-Light Physical Activity Time Ratio and Cognitive Function in Bariatric Surgery Candidates

Objective:Class III obesity is associated with increased risk for cognitive impairment. Though hypothesized to be partially attributable to sedentary time (ST), past research examining the association between ST and cognitive function has produced mixed findings. One possible explanation is that studies do not typically account for the highly correlated and almost inverse relationship between ST and light intensity physical activity (LPA), such that ST displaces time engaging in LPA. Therefore, we aimed to evaluate whether: (1) higher ST-to-LPA time ratio associates with poorer performance across multiple cognitive domains in patients with Class III obesity seeking bariatric surgery; and (2) the associations differ by sex.Participants and Methods:Participants (N = 121, 21-65 years of age, BMI &gt; 40 kg/m2) scheduled for either Roux-en-Y Gastric Bypass (RYGB) or Sleeve Gastrectomy (SG) completed the NIH Toolbox, a computerized neuropsychological assessment battery and wore a waist-mounted ActiGraph monitor during waking hours for 7 days to measure minutes/day spent in ST, LPA, and moderate-to-vigorous physical activity (MVPA). A ratio of time spent in ST-to-LPA was calculated by dividing the percentage of daily wear time spent in sedentary behavior (SB) by the percentage of daily wear time spent in LPA.Results:On average, participants (mean age = 43.22 years old and BMI = 45.83 kg/m2) wore the accelerometer for 909±176 minutes/day and spent 642±174 minutes/day in ST, 254±79 minutes/day in LPA, and 14±13 minutes/day in MVPA. Mean daily ST-to-LPA time ratio was 2.81 ± 1.3 (0.73-7.11). Overall, bivariate Pearson correlations found no significant relationships between LPA and cognitive performance on any of the NIH Toolbox subtests (r values = -.002 to -.158, all p values &gt;.05). Additionally, bivariate Pearson correlations also found no significant relationships between daily ST-to-LPA time ratio and cognitive performance on any of the subtests (r values = .003 to .108, all p values &gt;.05). However, higher ST-to-LPA was associated with lower scores on the Dimensional Change Card Sort Test in women (r = -.26, p = .01).Conclusions:Results showed that participants’ mean daily time spent in ST was 2.5 times higher than that spent in LPA and a higher ratio of ST-to-LPA was associated with poorer set-shifting in women with Class III obesity. Future studies should look to clarify underlying mechanisms, particularly studies examining possible sex differences in the cognitive benefits of PA. Similarly, intervention studies are also needed to determine if increasing LPA levels for individuals with Class III obesity would lead to improved cognitive performance by means of reducing ST.