Actigraphy Watch Research Articles

Hawthorne effect with transient behavioral and biochemical changes in a randomized controlled sleep extension trial of chronically short-sleeping obese adults: implications for the design and interpretation of clinical studies.

ObjectiveTo evaluate the effects of study participation per se at the beginning of a sleep extension trial between screening, randomization, and the run-in visit.DesignSubjects were screened, returned for randomization (Comparison vs. Intervention) after 81 days (median), and attended run-in visit 121 days later.SettingOutpatient.PatientsObese (N = 125; M/F, 30/95; Blacks/Whites/Other, N = 73/44/8), mean weight 107.6±19.7 kg, <6.5 h sleep/night.InterventionNon-pharmacological sleep extension.MeasurementsSleep duration (diaries and actigraphy watch), sleep quality (Pittsburgh Sleep Quality Index), daily sleepiness (Epworth Sleepiness Scale), fasting glucose, insulin and lipids.ResultsPrior to any intervention, marked improvements occurred between screening and randomization. Sleep duration increased (diaries: 357.4 ±51.2 vs. 388.1±48.6 min/night; mean±SD; P<0.001 screening vs. randomization; actigraphy: 344.3 ±41.9 vs. 358.6±48.2 min/night; P<0.001) sleep quality improved (9.1±3.2 vs. 8.2±3.0 PSQI score; P<0.001), sleepiness tended to improve (8.9±4.6 vs. 8.3±4.5 ESS score; P = 0.06), insulin resistance decreased (0.327±0.038 vs. 0.351±0.045; Quicki index; P<0.001), and lipids improved, except for HDL-C. Abnormal fasting glucose (25% vs. 11%; P = 0.007), and metabolic syndrome (42% vs. 29%; P = 0.007) both decreased. In absence of intervention, the earlier metabolic improvements disappeared at the run-in visit.LimitationsRelatively small sample size.ConclusionsImprovements in biochemical and behavioral parameters between screening and randomization changed the “true” study baseline, thereby potentially affecting outcome. While regression to the mean and placebo effect were considered, these findings are most consistent with the “Hawthorne effect”, according to which behavior measured in the setting of an experimental study changes in response to the attention received from study investigators. This is the first time that biochemical changes were documented with respect to the Hawthorne effect. The findings have implications for the design and conduct of clinical research.Trial RegistrationClinicalTrials.gov NCT00261898.

Sleep efficiency and nocturnal hemodynamic dipping in young, normotensive adults.

Blunted dipping of nocturnal systolic arterial pressure (SAP) and heart rate (HR) are independent risk factors for hypertension and all-cause mortality. While several epidemiological studies report a significant association between short sleep duration and hypertension, associations between sleep efficiency and the nocturnal drop of SAP remain controversial. Moreover, relations between sleep efficiency and HR diurnal patterns have been overlooked. We hypothesized that low sleep efficiency (<85%) would be associated with blunted nocturnal SAP and HR dipping. Twenty-two normotensive subjects (13 men, 9 women; age: 18-28 yr) wore an actigraphy watch for 7 days and nights, and an ambulatory blood pressure monitor for 24 h on a nonactigraph night. There were no differences in age, sex, body mass index, mean sleep time, number of awakenings, or 24-h blood pressure between the low (n = 12) and high (n = 10) sleep efficiency groups. However, the low sleep efficiency subjects demonstrated a blunted dip of nocturnal SAP (10 ± 1% vs. 14 ± 1%, P = 0.04) and HR (12 ± 3% vs. 21 ± 3%, P = 0.03) compared with the high sleep efficiency group. The low sleep efficiency group also demonstrated a higher mean nocturnal HR (63 ± 2 vs. 55 ± 2 beats/min; P = 0.02). These findings support growing evidence that sleep efficiency, independent of total sleep time, may be an important cardiovascular risk factor.

After lunch naps reduce the afternoon motor activity of 4-5-year old enrolled in full-time childcare

Objective. To determine the relationship between napping and the afternoon motor activity of preschool-aged children. Method. Par­ticipants were 42 healthy 4-5-year olds from two child care centers (CCCs) - one where children could choose whether or not to nap after lunch (CCC I) and another one where all children were encouraged to do so (CCC II). Each participant wore an actigraphy watch for seven days so that their sleep/wake cycle and afternoon motor activity were objectively measured. In order to compare the children´s mean afternoon motor activity on napping and non-napping days, all chil­dren were required not to nap on at least one weekday. Results. The children´s mean afternoon motor activity was negatively correlated to their mean nap duration (r=-0.46; p&lt;0.05 ). The mean motor activity was smaller on nap days compared to non-nap days for the CCC II (t = -2.33; p&lt;0.03) but not for the CCC I (t=0.96; p=0.35). Conclu­sion. After lunch naps reduce the afternoon motor activity of 4-5- year olds enrolled in full-time child care.

Cochilos reduzem a atividade motora de crianças de 4-5 anos que frequentam creches em período integral

Objective. To determine the relationship between napping and the afternoon motor activity of preschool-aged children. Method. Par­ticipants were 42 healthy 4-5-year olds from two child care centers (CCCs) - one where children could choose whether or not to nap after lunch (CCC I) and another one where all children were encouraged to do so (CCC II). Each participant wore an actigraphy watch for seven days so that their sleep/wake cycle and afternoon motor activity were objectively measured. In order to compare the children´s mean afternoon motor activity on napping and non-napping days, all chil­dren were required not to nap on at least one weekday. Results. The children´s mean afternoon motor activity was negatively correlated to their mean nap duration (r=-0.46; p&lt;0.05 ). The mean motor activity was smaller on nap days compared to non-nap days for the CCC II (t = -2.33; p&lt;0.03) but not for the CCC I (t=0.96; p=0.35). Conclu­sion. After lunch naps reduce the afternoon motor activity of 4-5- year olds enrolled in full-time child care.

Sleep efficiency associated with nocturnal blood pressure and heart rate dipping in young adults. (883.1)

Short sleep and fragmented sleep are associated with blunted nocturnal blood pressure (BP) dipping in humans. Despite epidemiological evidence that blunted nocturnal heart rate (HR) dipping is an independent risk factor for all‐cause mortality, the link between sleep efficiency and nocturnal HR dipping remains unclear. We hypothesized that subjects with low sleep efficiency (&lt;85%) would have blunted nocturnal BP and HR dipping compared to subjects with high sleep efficiency (&gt;85%). Twenty‐two normotensive subjects (13 men, 9 women; age 18‐28 years) wore an Actigraph watch for 7 days and nights, and an ambulatory BP monitor for 24 hours. There were no differences in age, sex, body mass index, mean sleep time, number of awakenings, or 24‐h blood pressure between the low (n=12) and high (n=10) sleep efficiency groups. However, the low sleep efficiency group demonstrated blunted dips in nocturnal systolic BP (9.9% vs. 14.2%, P=.04) and HR (12.4% vs. 21.4%, P=.03), as well as higher mean nocturnal HR (62.5 vs. 54.7 beats/min, P=.02), when compared to the high sleep efficiency group. In conclusion, our findings support growing evidence that sleep efficiency, independent of total sleep time, may be an important cardiovascular risk factor.

A101: The Impact of Sleep and Cytokine Levels on Pain Perception in JIA

Background/Purpose:Children with JIA experience more pain and disordered sleep than healthy children. JIA and poor sleep are associated with particular cytokine abnormalities, and the correlation between the two and how they relate to a patient's pain perception have not been studied. Elevation in TNF‐a, IL‐6, IL‐17, and IFN‐g have been found in the serum of children with JIA during active disease. Levels of proinflammatory cytokines are also increased during sleep loss. Indeed, blocking TNF‐a has been shown in adults with RA to improve sleep the night after the first dose. We hypothesize that dysfunctional sleep enhances pain in our patients and may be associated with abnormal cytokine profiles. In this pilot study, we hope to identify a subgroup of children with JIA that could benefit from intervention in improving sleep patterns.Methods:We plan to enroll 60 patients with JIA. Sleep is assessed by the sleep self‐report (SSR), the children's sleep habits questionnaire (CSHQ), and actigraphy. Good concordance in measurements of sleep duration has been established between PSG and actigraphy. Patients wear an actigraphy watch and keep a daily sleep and pain diary for 14 days. Disease activity is assessed using ESR, sum of active joints, patient/parent and physician global assessment of disease activity. Serum cytokine testing will be performed by flow cytometry.Results:31 patients are enrolled. We identified 7 children with disordered sleep using CSHQ/ SSR. These patients report having pain on most days, and they trend toward having elevated disease activity (increased physician and patient global assessments as well as number of active joints, ESR was non‐contributory). To date, 9 of the 31 patients underwent actigraphy. Preliminary data does not indicate an association between disease activity and objective sleep dysfunction. There is not yet enough data to comment on the association of pain and disordered sleep in the absence of disease activity. Serum from 22 patients has been collected for cytokine studies.Conclusion:There is a trend toward an association of perceived poor sleep (as reported subjectively by SSR/CSHQ) with increased pain and disease activity in our patient population. Increased disease activity does not appear to be objectively related to disordered sleep using actigraphy, however. So far, actigraphy has been conducted on patients without subjective complaints of sleep dysfunction. We plan to collect more objective data (via actigraphy) on patients with subjective sleep complaints (with and without active disease) to better characterize the relationship of pain and sleep. When this has been accomplished, we plan to investigate cytokine profiles in these groups.

The Correlation Between Sleep Efficiency and the Risk of Obstructive Sleep Apnea

Purpose: The purpose of this correlation research was to identify the relationship between Obstructive Sleep Apnea (OSA) and sleep efficiency. Subjects: A total of six men and twelve women (N=18) form the College of Health Professions fulfilled the requirements for inclusion in this study. Method: This research integrated two investigation methods. 1) STOP-BANG questionnaire was completed by students and faculty from the College of Health Professions at Texas State University. Then, 2) each participant wore an Actigraphy watch for seven days. The result of the STOP-BANG questionnaire was compared to the result of the Actigraphy in regard to low or high risk of OSA and the normal or below normal sleep efficiency. Results: There was no significant relationship between the risk of having OSA according to STOP-BANG and sleep efficiency measured by Actigraphy watch in undiagnosed individuals (r =.240, p =.337). However, there was a positive, significant relationship between age and sleep efficiency. Conclusion and Recommendations: In order to improve the external validity, more participants need to be included in future research. Moreover, the use of medication that could affect sleep and alcohol consumption need to addressed. A full night sleep study in a sleep lab adds a standard for comparison. Finally, using other questionnaires or advanced forms of Actigraphy technology could provide better results.

Actigraphically-defined sleep disturbance in Parkinson’s disease is associated with differential aspects of cognitive functioning

The frequency of sleep disturbance and cognitive impairment in Parkinson’s disease has led to the suggestion that these processes might share common neural circuitry. This study aimed to identify the relationships between measures of cognitive functioning and an objective measure of sleep disturbance. Ninety-five patients with idiopathic Parkinson’s disease and 48 healthy controls underwent neurological and neuropsychological examination. They wore an actigraphy watch for 2weeks, from which a measure of nocturnal sleep efficiency was calculated. Multiple regression models showed that working memory and verbal memory consolidation were significantly associated with sleep efficiency, as well as education and age. By contrast, verbal fluency and attentional set-shifting were not associated with sleep efficiency, after accounting for age and education. These findings reveal that nocturnal sleep disturbance in Parkinson’s disease is associated with specific cognitive difficulties, rather than a global pattern of cognitive dysfunction. This may in part reflect common neural underpinnings.

Sleep and sadness: exploring the relation among sleep, cognitive control, and depressive symptoms in young adults

BackgroundSleep disturbance is a common feature of depression. However, recent work has found that individuals who are vulnerable to depression report poorer sleep quality compared to their low-risk counterparts, suggesting that sleep disturbance may precede depression. In addition, both sleep disturbance and depression are related to deficits in cognitive control processes. Thus we examined if poor sleep quality predicts subsequent increases in depressive symptoms and if levels of cognitive control mediated this relation. MethodsThirty-five undergraduate students participated in two experimental sessions separated by 3weeks. Participants wore an actigraph watch between sessions, which provided an objective measure of sleep patterns. We assessed self-reported sleep quality and depressive symptoms at both sessions. Last, individuals completed an exogenous cuing task, which measured ability to disengage attention from neutral and negative stimuli during the second session. ResultsUsing path analyses, we found that both greater self-reported sleep difficulty and more objective sleep stability measures significantly predicted greater difficulty disengaging attention (i.e., less cognitive control) from negative stimuli. Less cognitive control over negative stimuli in turn predicted increased depression symptoms at the second session. Exploratory associations among the circadian locomotor output cycles kaput gene, CLOCK, single nucleotide polymorphism (SNP), rs11932595, as well as sleep assessments and depressive symptoms also are presented. ConclusionsThese preliminary results suggest that sleep disruptions may contribute to increases in depressive symptoms via their impact on cognitive control. Further, variation in the CLOCK gene may be associated with sleep quality.

The Relationships Between Poor Sleep Efficiency and Mild Cognitive Impairment in Parkinson Disease

Mild cognitive impairment (MCI) and sleep disturbances are common features in Parkinson disease (PD). This study sought to investigate whether patients with MCI in PD (PD-MCI) have more pronounced sleep disturbance compared to those without PD-MCI and whether phenotypic presentations differ according to the PD-MCI subtypes. A total of 95 patients with idiopathic PD (53 meeting criteria for PD-MCI and 42 who were not cognitively impaired) and 22 controls underwent neurological and neuropsychological examination. They wore actigraphy watches for 2 weeks, from which measures of nocturnal sleep efficiency were calculated. Patients with PD-MCI has significantly poorer sleep efficiency compared to those without PD-MCI. This effect was particularly apparent in those with multiple-domain PD-MCI, compared to those with single-domain PD-MCI. Furthermore, patients in the PD-MCI group had significantly more nontremor features. These data suggest that PD-MCI is associated with greater sleep disturbance and nontremor features of PD. This is further evidence for the potential role that sleep disturbance plays in the heterogeneity of PD.

Using Actigraphy to Measure Sleep Patterns in Rheumatoid Arthritis: A Pilot Study in Patients Taking Night‐Time Prednisone

ObjectivePoor sleep quality is a commonly reported but under-investigated consequence of rheumatoid arthritis (RA). Actigraphy is a non-invasive way of measuring sleep, estimated from the frequency and intensity of physical movement at the wrist. We used actigraphy to measure sleep parameters compared with sleep questionnaire data, and assessed the practicality of actigraph use in patients with RA.MethodsIn a pilot study of actigraphy conducted within an investigation of night-time prednisone treatment and circadian interleukin-6 concentrations in ten patients with active RA, we compared actigraphy with the St Mary’s Hospital Sleep Questionnaire and assessed whether night-time administration of prednisone resulted in increased sleep disturbance.ResultsThe actigraph watch was well tolerated by our patients, producing adequate data for analysis for 128 out of 133 test days (96.2%). The results indicated reasonable concordance between actigraph and sleep questionnaire data in the present sample. Patient satisfaction with sleep (question 11) strongly correlated with sleep efficiency measured by the actigraph (r = 0.71, p = 0.22) and showed a trend for inverse correlation with the fragmentation index (r = −0.60, p = 0.067). Quality of sleep (question 9) correlated non-significantly with the fragmentation index (r = −0.59, p = 0.072). We were unable to identify any significant correlations between clinical measures of disease and sleep parameters in this sample. There were no apparent detrimental consequences of the night-time dose of prednisone on the measures of sleep quality and quantity.ConclusionIn spite of the physical disability imposed by RA, the actigraph was well tolerated and gave a useful measure of sleep in patients with active disease. It has the potential for use in larger controlled trials.

Defining the Roles of Actigraphy and Parent Logs for Assessing Sleep Variables in Preschool Children

Actigraphy provides a non-invasive objective means to assess sleep–wake cycles. In young children, parent logs can also be useful for obtaining sleep–wake information. The authors hypothesized that actigraphy and parent logs were both equally valid instruments in healthy preschool-aged children. The authors studied 59 children aged 3 to 5 years in full-time day care. Each child was screened for medical problems and developmental delays before being fitted with an actigraphy watch, which was worn for 1 week. Parents maintained logs of sleep and wakefulness during the same period, with input from day care workers. In general, parents overestimated the amount of nighttime sleep measured by actigraphy by 13% to 22% (all significant). Although there was no difference in sleep onset times, parents reported later rise times on the weekend and fewer nighttime awakenings. There was no significant difference between parent logs and actigraphy with regard to daytime napping. The authors conclude that parent logs are best utilized in assessing daytime sleep and sleep onset, whereas actigraphy should be used to assess nighttime sleep and sleep offset time.

The Effects of Napping on Cognitive Function in Preschoolers

To determine the relationship between napping and cognitive function in preschool-aged children. Daytime napping, nighttime sleep, and cognitive function were assessed in 59 typically developing children aged 3 to 5 years, who were enrolled in full-time childcare. Participants wore an actigraphy watch for 7 days to measure sleep and napping patterns and completed neuropsychological testing emphasizing attention, response control, and vocabulary. Parents of participants completed behavior ratings and sleep logs during the study. Sleep/wake cycles were scored with the Sadeh algorithm. Children who napped more on weekdays were also more likely to nap during weekends. Weekday napping and nighttime sleep were inversely correlated, such that those who napped more slept less at night, although total weekday sleep remained relatively constant. Weekday napping was significantly (negatively) correlated with vocabulary and auditory attention span, and weekday nighttime sleep was positively correlated with vocabulary. Nighttime sleep was also significantly negatively correlated with performance, such that those who slept less at night made more impulsive errors on a computerized go/no-go test. Daytime napping is actually negatively correlated with neurocognitive function in preschoolers. Nighttime sleep seems to be more critical for development of cognitive performance. Cessation of napping may serve as a developmental milestone of brain maturation. Children who nap less do not appear to be sleep deprived, especially if they compensate with increased nighttime sleep. An alternative explanation is that children who sleep less at night are sleep deprived and require a nap. A randomized trial of nap restriction would be the next step in understanding the relationship between napping and neurocognitive performance.

Recurrent sudden movements resembling startle responses accompany duloxetine treatment

Duloxetine is a widely used selective serotonin and norepinephrine reuptake inhibitor. Known motor side effects include tremor, muscle cramps and symptoms of serotonin syndrome like overactive reflexes and restlessness. Behaviours consistent with increased motor reactivity, such as increased startle response to noise and decreased habituation of locomotor activity, were observed in rat pups after their mothers had been orally exposured to 30mg/kg/day of duloxetine throughout gestation and lactation. To all our knowledge, motor side effects of this kind have not been described yet in humans treated with duloxetine. Here we report two cases of depressed patients developing identical movement disturbances soon after their duloxetine dosage had been increased. Both, a 70 year old woman and a 31 year old man, experienced annoying jerks simultaneously involving the whole body. The involuntary movements resembled startle responses, except that no trigger preceded them. They reoccurred in irregular intervals preferably during rest periods. Consciousness, body balance and recall were not disturbed. Serum concentrations and EEG recordings were within normal range. When reducing the dosage, the movements decreased in frequency and then completely disappeared. In the second case the patient was able to document the incidents with an actigraph watch showing that their course paralleled the descending serum concentrations.