The effect of constraint-induced movement therapy assessed by accelerometry: the impact on daytime activity and sleep in children with cerebral palsy / O efeito da terapia por contensão induzida avaliada por meio de acelerômetros: o impacto na atividade diurna e no sono em crianças com paralisia cerebral

Abstract Introduction Spastic hemiparetic cerebral palsy (CP) is the most prevalent type of CP. Children with spastic hemiparesis experience difficulties when using their affected upper extremities, and one effective treatment is the Constraint-Induced Movement Therapy (CIMT). The study of rest-activity patterns provides information on children's daily activities with spastic hemiparetic CP during the day and sleep. Objective To investigate the effect of CIMT on the rest-activity patterns in children with spastic hemiparetic CP vs in a healthy group. Methods Nonrandomized controlled trial was conducted at the Neuropediatric Center of the Hospital de Clínicas Complex, in Curitiba, Brazil. Children with spastic hemi-paretic CP between 5 and 16 years old participated in the study group and receive the CIMT. The healthy group was composed of children between 5 and 15 years old. Both groups used accelerometer to record rest-activity patterns, that may be studied through nonparametric variables of accelerometer: M10 (an individual's most active 10h); L5 (an individual's least active 5h); and RA (relative amplitude of the circadian rest-activity patterns). Results Forty-five children were recruited, and 38 were included in the analyses (19 allocated to each group). In the study group, there was a significant increase in M10 and L5 (p < 0.001) after CIMT. The values of M10 and L5 were significantly higher (p < 0.001) in the healthy group compared to the study group after CIMT. Conclusion Our results showed that children with spastic hemiparetic CP became more active and participant in their daily life during the day as well as more efficient sleeping.

Resumo Introdução A paralisia cerebral (PC) hemiparética espástica é o tipo de PC mais prevalente. Crianças com hemiparesia es-pástica apresentam dificuldades ao usar as extremidades superiores afetadas e um tratamento eficaz é a Terapia por Contensão Induzida (TCI). O estudo dos padrões de atividade-repouso fornece informações sobre as atividades diárias de crianças com PC hemiparética espástica durante o dia e o sono. Objetivo Investigar o efeito da TCI nos padrões de repouso-atividade em crianças com PC hemiparética espástica versus um grupo saudável. Métodos Realizou-se um ensaio controlado não randomizado no Centro de Neuropediatria do Complexo do Hospital de Clínicas, Curitiba, Brasil. Crianças com PC hemi-parética espástica entre 5 e 16 anos participaram do grupo de estudo e receberam a TCI. O grupo saudável foi composto por crianças entre 5 e 15 anos. Ambos os grupos utilizaram um acelerômetro para registrar padrões de atividade-repouso, os quais podem ser estudados através de variáveis não paramé-tricas do acelerômetro: M10 (10h mais ativas de um indivíduo); L5 (5h menos ativas de um indivíduo); e AR (amplitude rela-tiva dos padrões de atividade-repouso). Resultados Foram recrutadas 45 crianças e 38 foram incluídas nas análises (19 alocadas em cada grupo). No grupo de estudo, houve aumento significativo de M10 e L5 (p < 0,001) após TCI. Os valores de M10 e L5 foram significativamente maiores (p < 0,001) no grupo saudável em comparação ao grupo de estudo após TCI. Conclusão Os resultados do presente estudo mostraram que crianças com PC hemiparética espástica tornaram-se mais ativas e participantes de sua vida diária durante o dia, bem como dormiram mais eficientemente.

Rest-activity profiles among U.S. adults in a nationally representative sample: a functional principal component analysis.

BACKGROUND: The 24-h rest and activity behaviors (i.e., physical activity, sedentary behaviors and sleep) are fundamental human behaviors essential to health and well-being. Functional principal component analysis (fPCA) is a flexible approach for characterizing rest-activity rhythms and does not rely on a priori assumptions about the activity shape. The objective of our study is to apply fPCA to a nationally representative sample of American adults to characterize variations in the 24-h rest-activity pattern, determine how the pattern differs according to demographic, socioeconomic and work characteristics, and examine its associations with general health status. METHODS: The current analysis used data from adults 25 or older in the National Health and Nutrition Examination Survey (NHANES, 2011-2014). Using 7-day 24-h actigraphy recordings, we applied fPCA to derive profiles for overall, weekday and weekend rest-activity patterns. We examined the association between each rest-activity profile in relation to age, gender, race/ethnicity, education, income and working status using multiple linear regression. We also used multiple logistic regression to determine the relationship between each rest-activity profile and the likelihood of reporting poor or fair health. RESULTS: We identified four distinct profiles (i.e., high amplitude, early rise, prolonged activity window, biphasic pattern) that together accounted for 86.8% of total variation in the study sample. We identified numerous associations between each rest-activity profile and multiple sociodemographic characteristics. We also found evidence suggesting the associations differed between weekdays and weekends. Finally, we reported that the rest-activity profiles were associated with self-rated health. CONCLUSIONS: Our study provided evidence suggesting that rest-activity patterns in human populations are shaped by multiple demographic, socioeconomic and work factors, and are correlated with health status.

Longitudinal changes in sleep patterns and circadian rhythm metrics in preschool-age children from Northern Mexico.

OBJECTIVES: To assess changes in sleep parameters and circadian rhythm metrics measured by actigraphy in preschool-aged children. DESIGN: Longitudinal analysis over 1 year. PARTICIPANTS: Ninety-four children living in Tijuana and Ensenada, Mexico. MEASUREMENTS: Children wore accelerometers on the right hip for one continuous week at baseline and 1-year follow-up. Parents recorded child bedtime, waketime, and naps in sleep diaries. We used cosinor and nonparametric approaches to calculate circadian rhythm metrics. RESULTS: At baseline, children had a mean age of 4.2 years, and 51.1% were girls. In multivariable models adjusted for age, gender, BMI category, parental education, household income and city, at follow-up children had significantly earlier waketimes (ß = -7.99 minutes, p < .001) compared to baseline. Children also had lower sleep onset latency (ß = -2.32 minutes, p = .057), and longer nighttime sleep (ß = 9.38 minutes, p = .079), but these changes were not significant at the α < 0.05 level. We found significant increases in log relative amplitude (ß = 0.017, p = .009), and decreases in log midline estimated statistic of rhythm (ß = -0.084, p = .017) and log of the least active 5-hour period (ß = -0.057, p = .010). When we adjusted for co-sleeping, we found significant decreases in the number of nighttime awakenings (ß = -1.29, p = .011) but otherwise similar results. There were no other changes in sleep parameters or circadian rhythm metrics. CONCLUSIONS: Mean increases in nighttime sleep and earlier wake times over one year were concomitant with decreases in overall activity levels and increases in circadian rhythm robustness. Co-sleeping was a predictor of sleep disturbances. This study provides longitudinal evidence regarding changes in sleep and circadian metrics in a sample of children from an under-researched sociodemographic group during an important, early life period.

Associations of rest-activity patterns with amyloid burden, medial temporal lobe atrophy, and cognitive impairment.

BACKGROUND: We sought to investigate the possible associations of rest-activity patterns with cortical amyloid burden, medial temporal lobe (MTL) neurodegeneration, and cognitive function in patients in the early stage of cognitive impairment. METHODS: Rest-activity patterns were assessed in 100 participants (70 with mild cognitive impairment and 30 with mild dementia) using wrist actigraphy. All participants underwent 18F-flutemetamol positron emission tomography (PET) imaging to quantify cortical amyloid burden, structural brain magnetic resonance imaging (MRI) to quantify MTL grey matter volume, neuropsychological testing, and clinical diagnosis. We used multiple linear regression models adjusted for covariates, including demographics, diabetes, hypertension, depressive symptom, psychotropic medication, sleep medication, weekend effect, and apolipoprotein-ε allele status. FINDINGS: After adjusting for possible confounders, we found that the midline estimation of statistic of rhythm (MESOR) associated positively with frontal/executive function (estimate = 1.17, standard error [SE] = 0.37, p = 0.002). The least active 5-h (L5) onset time associated positively with MTL grey matter volume and memory function (estimate = 1.24, SE = 0.33, p = 0.001, and estimate = 3.77, SE = 1.22, p = 0.003, respectively), particularly in amyloid-negative participants. Additional path analysis revealed that MTL grey matter volume partially mediated the association between L5 onset time and memory function in amyloid-negative participants. INTERPRETATION: Decreased MESOR and advanced L5 onset time may be useful as early signs of cognitive decline or MTL neurodegeneration. Furthermore, amyloid pathology may act as a moderator of the relationships between rest-activity patterns, neurodegeneration, and cognitive function. FUNDING: Korea Centres for Disease Control and Prevention (#4845-303); National Research Foundation of Korea (2019M3C7A1031905, 2019R1A5A2026045).

Association of Daily Rest-Activity Patterns With Adiposity and Cardiometabolic Risk Measures in Teens.

PURPOSE: Emerging data indicate that the timing and rhythms of energetic behaviors may influence metabolism and obesity risk. Our aim was to derive diurnal rest-activity patterns from actigraphy in adolescents and analyze associations with adiposity measures and cardiometabolic risk factors. METHODS: Adolescents in the Project Viva cohort wore a wrist actigraph over 7 days. We derived markers of daily rest-activity patterns from actigraphy using nonparametric models, generating measurements of relative amplitude (RA). RA reflects the normalized difference in activity measured during the most active 10-hour period and the least active 5-hour period, averaged over multiple 24-hour periods. Using multivariable-adjusted linear regression models, we estimated associations of RA and its components with markers of adiposity (body mass index, waist circumference, skinfolds, dual-energy X-ray absorptiometry fat mass) and cardiometabolic health (cardiometabolic risk score, derived as the mean of five sex-specific internal z-scores for waist circumference, systolic blood pressure, high-density lipoprotein cholesterol scaled inversely, and log-transformed triglycerides and homeostatic model assessment of insulin resistance). RESULTS: A total of 778 adolescents provided at least 5 days of valid actigraphy data. The average age was 13.2 (±.9) years, 52% were female, and the average RA was .9 (±.1). A higher RA reflecting higher activity during wakefulness and lower activity during the night was associated with more favorable indices of adiposity (e.g., -.35 kg/m2 lower body mass index per each .04 units increment of RA; 95% confidence interval: -.60 to -.09). CONCLUSIONS: In this large sample of adolescents, a higher RA emerged as a novel biomarker, associated with more favorable cardiometabolic profiles.

Zeitgebers and their association with rest-activity patterns.

Zeitgebers such as light, eating and physical activity provide input to the circadian clock. Chronic circadian misalignment is associated with significant adverse health effects. An improved understanding of the impact of the timing of zeitgebers on the stability of 24-hour rest-activity rhythm in free-living settings may identify behavioural and environmental intervention targets. A total of 133 healthy adults, aged 21-60 years, wore a wrist actigraph for 7 consecutive days. We applied a non-parametric analysis to activity counts to derive rest-activity patterns. We administered a questionnaire through a smartphone app to collect self-reported timing of light exposure, eating episodes and physical activity. To assess the relationship between timing exposures (first and last exposure to outdoor light, first exposure to indoor light, last eating episode, first eating episode, morning physical activity proportion, evening physical activity proportion) and rest-activity or sleep outcomes (bedtimes, total sleep time, inter-daily stability, intra-daily variability, L5 and M10 midpoint), we first calculated Spearman correlations, using the false discovery rate method to control for multiple comparisons. From those significant associations, we then fit regression models adjusting for age, sex, race, household income, education level, study site, body mass index, as well as physical activity. Finally, we tested for interaction between chronotype and each timing-related exposure and stratified the analysis by morning type. All zeitgebers, except for evening physical activity proportion, were correlated with at least four of the seven sleep and rest-activity outcomes. In adjusted analysis, later timing of first (after 6:30 to 7:45 AM versus earlier) and last exposure to indoor light (after 11:00 PM versus earlier) and first (after 7:45-9:45 AM versus earlier) and last eating episode (after 8:00-09:00 PM versus earlier) were associated with a shift of 0.60-1.39 hours to later bedtimes, M10 and L5 midpoints (i.e. timing of peak activities or inactivities). Later timing of first exposure to outdoor light (after 09:30 AM versus earlier) was also associated with 0.51 (95% CI: 0.19 to 0.83) hours longer total sleep time. Higher morning physical activity proportion (> 33%) was associated with 0.95 (95% CI: -1.38 to -0.53) hours earlier in-bed time and 0.69 (95% CI: -1.14 to -0.24) hours earlier out-of-bed time, 0.92 (95% CI: -1.41 to -0.42) hours earlier M10 and 0.96 (95% CI: -1.42 to -0.49) min earlier L5 midpoint. The results did not change substantially with further adjustment for total activity. There was a significant interaction between morning chronotype and first eating episode with rest-activity patterns (p < 0.05), with first eating episode associating with timing of activities only in non-morning type adults. Timing of zeitgebers was associated with sleep and rest-activity patterns, including bedtimes, L5 and M10 midpoint. Future research should evaluate the impact of manipulating zeitgebers on both circadian rhythms and health outcomes.

Actigraphy-Derived Daily Rest-Activity Patterns and Body Mass Index in Community-Dwelling Adults.

Study Objectives: To examine associations between 24-hour rest-activity patterns and body mass index (BMI) among community-dwelling US adults. Rest-activity patterns provide a field method to study exposures related to circadian rhythms. Methods: Adults (N = 578) wore an actigraph on their nondominant wrist for 7 days. Intradaily variability and interdaily stability (IS), M10 (most active 10-hours), L5 (least active 5-hours), and relative amplitude (RA) were derived using nonparametric rhythm analysis. Mesor, acrophase, and amplitude were calculated from log-transformed count data using the parametric cosinor approach. Results: Participants were 80% female and mean (standard deviation) age was 52 (15) years. Participants with higher BMI had lower values for magnitude, RA, IS, total sleep time (TST), and sleep efficiency. In multivariable analyses, less robust 24-hour rest-activity patterns as represented by lower RA were consistently associated with higher BMI: comparing the bottom quintile (least robust) to the top quintile (most robust 24-hour rest-activity pattern) of RA, BMI was 3-kg/m2 higher (p = .02). Associations were similar in magnitude to an hour less of TST (1-kg/m2 higher BMI) or a 10% decrease in sleep efficiency (2-kg/m2 higher BMI), and independent of age, sex, race, education, and the duration of rest and/or activity. Conclusions: Lower RA, reflecting both higher night activity and lower daytime activity, was associated with higher BMI. Independent of the duration of rest or activity during the day or night, 24-hour rest, and activity patterns from actigraphy provide aggregated measures of activity that associate with BMI in community-dwelling adults.

Variation in actigraphy-estimated rest-activity patterns by demographic factors.

Rest-activity patterns provide an indication of circadian rhythmicity in the free-living setting. We aimed to describe the distributions of rest-activity patterns in a sample of adults and children across demographic variables. A sample of adults (N = 590) and children (N = 58) wore an actigraph on their nondominant wrist for 7 days and nights. We generated rest-activity patterns from cosinor analysis (MESOR, acrophase and magnitude) and nonparametric circadian rhythm analysis (IS: interdaily stability; IV: intradaily variability; L5: least active 5-hour period; M10: most active 10-hour period; and RA: relative amplitude). Demographic variables included age, sex, race, education, marital status, and income. Linear mixed-effects models were used to test for demographic differences in rest-activity patterns. Adolescents, compared to younger children, had (1) later M10 midpoints (ß = 1.12 hours [95% CI: 0.43, 1.18] and lower M10 activity levels; (2) later L5 midpoints (ß = 1.6 hours [95% CI: 0.9, 2.3]) and lower L5 activity levels; (3) less regular rest-activity patterns (lower IS and higher IV); and 4) lower magnitudes (ß = -0.95 [95% CI: -1.28, -0.63]) and relative amplitudes (ß = -0.1 [95% CI: -0.14, -0.06]). Mid-to-older adults, compared to younger adults (aged 18-29 years), had (1) earlier M10 midpoints (ß = -1.0 hours [95% CI: -1.6, -0.4]; (2) earlier L5 midpoints (ß = -0.7 hours [95% CI: -1.2, -0.2]); and (3) more regular rest-activity patterns (higher IS and lower IV). The magnitudes and relative amplitudes were similar across the adult age categories. Sex, race and education level rest-activity differences were also observed. Rest-activity patterns vary across the lifespan, and differ by race, sex and education. Understanding population variation in these patterns provides a foundation for further elucidating the health implications of rest-activity patterns across the lifespan.

Rest-Activity Patterns in Older Adults with Heart Failure and Healthy Older Adults.

The purpose of this investigation is to examine differences in rest-activity patterns and sleep characteristics in older adults with heart failure (HF) and healthy older adults. The sample included older adults with HF (n = 20) and a reference group of healthy older adults (n = 20). Traditional cosinor analysis was used to assess three parameters of rest-activity from wrist actigraphy data: amplitude (range of activity), mesor (mean activity), and acrophase (time of peak activity). Traditional sleep characteristics were also determined from actigraphy data: total sleep time (TST), sleep latency (SL), sleep efficiency (SE), and wake after sleep onset (WASO). The HF group demonstrated significantly lower mesor and amplitude than the reference group (p < .01). The HF group had significantly greater TST (p < .01), but the groups had similar SE, SL, and WASO. Despite similar sleep characteristics to healthy older adults, overall rest-activity patterns were significantly dampened in those with HF.

A pilot study of sleep quality and rest-activity patterns in persons living with HIV.

As much as 73% of persons living with HIV (PLWH) experience sleep disturbances. It has been more than 10 years since the last study that objectively measured sleep behaviors in persons with HIV. The purpose of this pilot study was to explore sleep quality and rest-activity patterns in PLWH. Eight participants completed a sleep diary and 24-hour actigraphy for 1 week. Compared to accepted norms for "good sleepers," sleep diaries described moderate sleep disturbance, and actigraphy revealed severe sleep disturbance. Bedtime was variable from day to day. Analysis of 24-hour rest-activity patterns from actigraphy also indicated disorganization of sleep timing across days. Results of this pilot study suggest that sleep disturbance remains problematic in PLWH despite advancements in the disease management. Pharmacological interventions are effective but generally recommended for short-term use. Behavioral treatments may be useful for longer-term management of sleep patterns in PLWH, but further research is needed.

Comparisons of three practical field devices used to measure personal light exposures and activity levels.

This paper documents the spectral and spatial performance characteristics of two new versions of the Daysimeter, devices developed and calibrated by the Lighting Research Center to measure and record personal circadian light exposure and activity levels, and compares them to those of the Actiwatch Spectrum (Philips Healthcare). Photometric errors from the Daysimeters and the Actiwatch Spectrum were also determined for various types of light sources. The Daysimeters had better photometric performance than the Actiwatch Spectrum. To assess differences associated with measuring light and activity levels at different locations on the body, older adults wore four Daysimeters and an Actiwatch Spectrum for five consecutive days. Wearing the Daysimeter or Actiwatch Spectrum on the wrist compromises accurate light measurements relative to locating a calibrated photosensor at the plane of the cornea.