Abstract: Importance Sleep and circadian problems are very common in Alzheimer disease (AD). Recent animal studies suggest a bidirectional relationship between sleep and β-amyloid (Aβ), a key molecule involved in AD pathogenesis. Objective To test whether Aβ deposition in preclinical AD, prior to the appearance of cognitive impairment, is associated with changes in quality or quantity of sleep. Design Cross-sectional study conducted from October 2010 to June 2012. Setting General community volunteers at the Washington University Knight Alzheimer's Disease Research Center. Participants Cognitively normal individuals (n = 145) 45 years and older were recruited from longitudinal studies of memory and aging at the Washington University Knight Alzheimer's Disease Research Center. Valid actigraphy data were recorded in 142. The majority (124 of 142) were recruited from the Adult Children Study, in which all were aged 45 to 75 years at baseline and 50% have a parental history of late-onset AD. The rest were recruited from a community volunteer cohort in which all were older than 60 years and healthy at baseline. Main Outcome Measures Sleep was objectively measured using actigraphy for 2 weeks. Sleep efficiency, which is the percentage of time in bed spent asleep, was the primary measure of sleep quality. Total sleep time was the primary measure of sleep quantity. Cerebrospinal fluid Aβ42 levels were used to determine whether amyloid deposition was present or absent. Concurrent sleep diaries provided nap information. Results Amyloid deposition, as assessed by Aβ42 levels, was present in 32 participants (22.5%). This group had worse sleep quality, as measured by sleep efficiency (80.4% vs 83.7%), compared with those without amyloid deposition, after correction for age, sex, and APOE ϵ4 allele carrier status (P = .04). In contrast, quantity of sleep was not significantly different between groups, as measured by total sleep time. Frequent napping, 3 or more days per week, was associated with amyloid deposition (31.2% vs 14.7%; P = .03). Conclusions and Relevance Amyloid deposition in the preclinical stage of AD appears to be associated with worse sleep quality but not with changes in sleep quantity.

Abstract: Objective Cross-sectional studies suggest that sleep fragmentation is associated with cognitive performance in older adults. We tested the hypothesis that sleep fragmentation is associated with incident Alzheimer's disease (AD) and the rate of cognitive decline in older adults. Design Prospective cohort study. Setting Community-based. Participants 737 community dwelling older adults without dementia. Measurements and results Sleep fragmentation was quantified from up to 10 consecutive days of actigraphy. Subjects underwent annual evaluation for AD with 19 neuropsychological tests. Over a follow-up period of up to 6 years (mean 3.3 years), 97 individuals developed AD. In a Cox proportional hazards model controlling for age, sex, and education, a higher level of sleep fragmentation was associated with an increased risk of AD (HR = 1.22, 95%CI 1.03-1.44, P = 0.02 per 1SD increase in sleep fragmentation). An individual with high sleep fragmentation (90th percentile) had a 1.5-fold risk of developing AD as compared with someone with low sleep fragmentation (10th percentile). The association of sleep fragmentation with incident AD did not vary along demographic lines and was unchanged after controlling for potential confounders including total daily rest time, chronic medical conditions, and the use of common medications which can affect sleep. In a linear mixed effect analysis, a 0.01 unit increase in sleep fragmentation was associated with a 22% increase in the annual rate of cognitive decline relative to the average rate of decline in the cohort (Estimate = -0.016, SE = 0.007, P = 0.03). Conclusions Sleep fragmentation in older adults is associated with incident AD and the rate of cognitive decline. Citation Lim ASP; Kowgier M; Yu L; Buchman AS; Bennett DA. Sleep fragmentation and the risk of incident alzheimer's disease and cognitive decline in older persons. SLEEP 2013;36(7):1027-1032.

Abstract: While there is a large body of evidence that poor subjective sleep quality is related to lower subjective well-being, studies on the relation of objective sleep measures and subjective well-being are fewer in number and less consistent in their findings. Using data of the Survey of Mid-Life in the United States (MIDUS), we investigated whether duration and quality of sleep, assessed by actigraphy, were related to subjective well-being and whether this relationship was mediated by subjective sleep quality. Three hundred and thirteen mainly white American individuals from the general population and 128 urban-dwelling African American individuals between 35 and 85 years of age were studied cross-sectionally. Sleep duration, variability of sleep duration, sleep onset latency, and time awake after sleep onset were assessed by actigraphy over a period of 7 days. Subjective sleep quality was assessed with the Pittsburgh Sleep Quality Index, positive psychological well-being and symptoms of psychological distress were assessed with the Satisfaction with Life Scale and the Mood and Anxiety Symptom Questionnaire. In both white and African Americans high day-to-day variability in sleep duration was related to lower levels of subjective well-being controlling age, gender, educational and marital status, and BMI. By contrast, sleep duration, sleep onset latency, and time awake after sleep onset were not related to subjective well-being controlling covariates and other sleep variables. Moreover, the relationship between variability in sleep duration and well-being was partially mediated by subjective sleep quality. The findings show that great day-to-day variability in sleep duration – more than average sleep duration – is related to poor subjective sleep quality and poor subjective well-being.

Abstract: Background Short sleep duration and decreased sleep quality are emerging risk factors for obesity and its associated morbidities. Chronotype, an attribute that reflects individual preferences in the timing of sleep and other behaviors, is a continuum from morningness to eveningness. The importance of chronotype in relation to obesity is mostly unknown. Evening types tend to have unhealthy eating habits and suffer from psychological problems more frequently than Morning types, thus we hypothesized that eveningness may affect health parameters in a cohort of obese individuals reporting sleeping less than 6.5 hours per night. Methodology and Principal Findings Baseline data from obese (BMI: 38.5±6.4 kg/m2) and short sleeping (5.8±0.8 h/night by actigraphy) participants (n = 119) of the Sleep Extension Study were analyzed (www.ClinicalTrials.gov, identifier NCT00261898). Assessments included the Horne and Ostberg Morningness-Eveningness questionnaire, a three-day dietary intake diary, a 14-day sleep diary, 14 days of actigraphy, and measurements of sleep apnea. Twenty-four hour urinary free cortisol, 24 h urinary norepinephrine and epinephrine levels, morning plasma ACTH and serum cortisol, fasting glucose and insulin, and lipid parameters were determined. Eveningness was associated with eating later in the day on both working and non-working days. Progression towards eveningness was associated with an increase in BMI, resting heart rate, food portion size, and a decrease in the number of eating occasions and HDL-cholesterol. Evening types had overtly higher 24 h urinary epinephrine and morning plasma ACTH levels, and higher morning resting heart rate than Morning types. In addition, Evening types more often had sleep apnea, independent of BMI or neck circumference. Conclusions Eveningness was associated with eating later and a tendency towards fewer and larger meals and lower HDL-cholesterol levels. In addition, Evening types had more sleep apnea and higher stress hormones. Thus, eveningness in obese, chronically sleep-deprived individuals compounds the cardiovascular risk associated with obesity.

Abstract: Objective: Toward explicating relations between economic adversity and children’s sleep, we examined associations between multiple indicators of socioeconomic status (SES)/adversity and children’s objectively and subjectively derived sleep parameters; ethnicity was examined as potential moderator. Methods: Participants were 276 third- and fourth-grade children and their families (133 girls; M age 9.44 years; SD .71): 66% European American (EA) and 34% African American (AA). Four SES indicators were used: income-to-needs ratio, perceived economic well-being, maternal education, and community poverty. Children wore actigraphs for 7 nights and completed a self-report measure to assess sleep problems. Results: Objectively and subjectively assessed sleep parameters were related to different SES indicators, and overall worse sleep was evident for children from lower SES homes. Specifically, children from homes with lower income-to-needs ratios had higher levels of reported sleep/wake problems. Parental perceived economic well-being was associated with shorter sleep minutes and greater variability in sleep onset for children. Lower mother’s education was associated with lower sleep efficiency. Children who attended Title 1 schools had shorter sleep minutes. Ethnicity was a significant moderator of effects in the link between some SES indicators and children’s sleep. AA children’s sleep was more negatively affected by income-to-needs ratio and mother’s education than was the sleep of EA children. Conclusions: The results advocate for the importance of specifying particular SES and sleep variables used because they may affect the ability to detect associations between sleep and economic adversity.

Abstract: Study objective To examine the relationship between sleep and dietary intake in adolescents using an experimental sleep restriction protocol. Design Randomized crossover sleep restriction-extension paradigm. Setting Sleep obtained and monitored at home, diet measured during an office visit. Participants Forty-one typically developing adolescents age 14-16 years. Interventions The 3-week protocol consisting of a baseline week designed to stabilize the circadian rhythm, followed randomly by 5 consecutive nights of sleep restriction (6.5 hours in bed Monday-Friday) versus healthy sleep duration (10 hours in bed), a 2-night washout period, and a 5-night crossover period. Measurements Sleep was monitored via actigraphy and teens completed validated 24-hour diet recall interviews following each experimental condition. Results Paired-sample t-tests examined differences between conditions for consumption of key macronutrients and choices from dietary categories. Compared with the healthy sleep condition, sleep-restricted adolescents' diets were characterized by higher glycemic index and glycemic load and a trend toward more calories and carbohydrates, with no differences in fat or protein consumption. Exploratory analyses revealed the consumption of significantly more desserts and sweets during sleep restriction than healthy sleep. Conclusions Chronic sleep restriction during adolescence appears to cause increased consumption of foods with a high glycemic index, particularly desserts/sweets. The chronic sleep restriction common in adolescence may cause changes in dietary behaviors that increase risk of obesity and associated morbidity.

Abstract: Women are at increased risk of developing mood disorders during the postpartum period, and poor postpartum sleep may be a modifiable risk factor for the development of depression. This longitudinal study investigated the relationship between sleep variables and postpartum depression symptoms using wrist actigraphy and self-report surveys. Twenty-five healthy primiparous women were recruited from their outpatient obstetricians’ offices from July 2009 through March 2010. Subjects wore wrist actigraphs for 1 week during the third trimester of pregnancy and again during the 2nd, 6th, 10th, and 14th weeks postpartum while completing sleep logs and sleep surveys. Subjective assessments of mood were collected at the end of each actigraph week. Subjective sleep assessments were strongly predictive of depression severity scores as measured by the Edinburgh Postnatal Depression Scale (EPDS) across all weeks (p < 0.001). Actigraphic measures of sleep maintenance, such as sleep fragmentation, sleep efficiency, and wake time after sleep onset, were also significantly correlated with EPDS scores postpartum. However, there was no relationship between nocturnal sleep duration and EPDS scores. This study provides additional evidence that poor sleep maintenance as measured by wrist actigraphy, rather than lesser amounts of sleep, is associated with EPDS scores during the postpartum period and that subjective assessments of sleep may be more accurate predictors of postpartum depression symptoms than wrist actigraphy. It also supports the hypothesis that disrupted sleep may contribute to the development and extent of postpartum depression symptoms.

Abstract: The rhythms of activity across the 24-h sleep-wake cycle, determined in part by the circadian clock, change with aging. Few large-scale studies measured the activity rhythm objectively in the general population. The present population-based study in middle-aged and elderly persons evaluated how activity rhythms change with age, and additionally investigated sociodemographics, mental health, lifestyle, and sleep characteristics as determinants of rhythms of activity. Activity rhythms were measured objectively with actigraphy. Recordings of at least 96 h (138 ± 14 h, mean ± SD) were collected from 1734 people (age: 62 ± 9.4 yrs) participating in the Rotterdam Study. Activity rhythms were quantified by calculating interdaily stability, i.e., the stability of the rhythm over days, and intradaily variability, i.e., the fragmentation of the rhythm relative to its 24-h amplitude. We assessed age, gender, presence of a partner, employment, cognitive functioning, depressive symptoms, body mass index (BMI), coffee ...

Abstract: Background:Exercise improves sleep quality, mood, and quality of life among older adults with insomnia. The purpose of the study was to evaluate the daily bidirectional relationships between exerci...

Abstract: Background In research and clinical contexts, parent reports are often used to gain information about the sleep patterns of their adolescents; however, the degree of concordance between parent reports and adolescent-derived measures is unclear. The present study compares parent estimates of adolescent sleep patterns with adolescent self-reports from surveys and sleep diaries, together with actigraphy. Methods A total of 308 adolescents (59% male) aged 13-17 years completed a school sleep habits survey during class time at school, followed by a 7-day sleep diary and wrist actigraphy. Parents completed the Sleep, Medical, Education and Family History Survey. Results Parents reported an idealized version of their adolescent's sleep, estimating significantly earlier bedtimes on both school nights and weekends, significantly later wake times on weekends, and significantly more sleep than either the adolescent self-reported survey, sleep diary, or actigraphic estimates. Conclusion Parent reports indicate that the adolescent averages a near-optimal amount of sleep on school nights and a more than optimal amount of sleep on weekends. However, adolescent-derived averages indicate patterns of greater sleep restriction. These results illustrate the importance of using adolescent-derived estimates of sleep patterns in this age group and the importance of sleep education for both adolescents and their parents.

Abstract: Study Objectives The majority of adolescent sleep research has utilized self-reported sleep duration and some have based information on a solitary question. Whilst some have claimed to have validated sleep survey data with objective actigraphy measures in adolescents, the statistical approach applied only demonstrates the strength of the association between subjective and objective sleep duration data and does not reflect if these different methods actually agree.

Abstract: The success of interplanetary human spaceflight will depend on many factors, including the behavioral activity levels, sleep, and circadian timing of crews exposed to prolonged microgravity and confinement. To address the effects of the latter, we used a high-fidelity ground simulation of a Mars mission to objectively track sleep–wake dynamics in a multinational crew of six during 520 d of confined isolation. Measurements included continuous recordings of wrist actigraphy and light exposure (4.396 million min) and weekly computer-based neurobehavioral assessments (n = 888) to identify changes in the crew's activity levels, sleep quantity and quality, sleep–wake periodicity, vigilance performance, and workload throughout the record-long 17 mo of mission confinement. Actigraphy revealed that crew sedentariness increased across the mission as evident in decreased waking movement (i.e., hypokinesis) and increased sleep and rest times. Light exposure decreased during the mission. The majority of crewmembers also experienced one or more disturbances of sleep quality, vigilance deficits, or altered sleep–wake periodicity and timing, suggesting inadequate circadian entrainment. The results point to the need to identify markers of differential vulnerability to hypokinesis and sleep–wake changes during the prolonged isolation of exploration spaceflight and the need to ensure maintenance of circadian entrainment, sleep quantity and quality, and optimal activity levels during exploration missions. Therefore, successful adaptation to such missions will require crew to transit in spacecraft and live in surface habitats that instantiate aspects of Earth's geophysical signals (appropriately timed light exposure, food intake, exercise) required for temporal organization and maintenance of human behavior.

Abstract: Summary The prevalence of insomnia increases with age. Short sleep duration is associated with deficits in cognitive performance. We hypothesized that short sleep duration and sleep quality influence cognitive performance in older adults. The study included 78 adults aged 60 years and over (72.2 ± 5.9 years). Total sleep time and sleep efficiency (total sleep time/time in bed × 100) were calculated using actigraphy. We evaluated cognitive performance with the continuous performance test-identical pairs and the number-back test. Sleep apnea was evaluated overnight with a portable home monitoring system. The accuracy of the 0-back test significantly decreased in participants with total sleep time less than 5 h compared with those with total sleep time greater than 7 h, but there was no significant difference in continuous performance test-identical pairs between the two groups. Participants with sleep efficiency <85% showed a significant decrease in 0- and 1-back test accuracy compared with those with sleep efficiency ≥85%. There were no significant differences in the accuracy of number-back tests and continuous performance test-identical pairs between apnea–hypopnea index ≥15 h−1 and apnea–hypopnea index <15 h−1 groups, or among lowest SpO2 ≥ 90%, lowest 80–90%, and lowest SpO2 < 80% groups. Age, total sleep time and sleep efficiency were significantly correlated with accuracy on the 0-back test. Age and sleep efficiency were significantly correlated with accuracy on the 1-back test. Multiple regression analysis revealed that total sleep time was independently correlated with accuracy on the 0-back test, while age was independently correlated with accuracy on the 1-back test. Our findings suggest that sleep duration and sleep quality may play a role in cognitive performance in older adults.

Abstract: Objective To evaluate the effectiveness of a behavioural-educational sleep intervention delivered in the early postpartum in improving maternal and infant sleep. Design Randomised controlled trial. Setting Postpartum units of two university affiliated hospitals. Participants 246 primiparous women and their infants randomised while in hospital with an internet based randomisation service to intervention (n=123) or usual care (n=123) groups. Interventions The behavioural-educational sleep intervention included a 45-60 minute meeting with a nurse to discuss sleep information and strategies to promote maternal and infant sleep, a 20 page booklet with the content discussed, and phone contacts at one, two, and four weeks postpartum to reinforce information, provide support, and problem solve. The usual care group received calls at weeks one, two, and four to maintain contact without provision of advice. Main outcome measures Primary outcome was maternal nocturnal (9 pm to 9 am) sleep (minutes) and secondary outcome was longest stretch of infant nocturnal sleep (minutes) measured at six and 12 weeks postpartum by actigraphy. Other outcomes measured at six and 12 weeks were number of maternal and infant night time awakenings by actigraphy, fatigue visual analogue scale, general sleep disturbance scale, and Edinburgh postnatal depression scale. Rates of exclusive breast feeding were measured at 12 weeks postpartum only. Results All women who completed any outcome measures at six or 12 weeks were included in analysis. Sleep outcomes were completed at one or both of six and 12 weeks postpartum for 215 of 246 (87%) women (110/123 intervention and 105/123 usual care). Longitudinal mixed effects model analyses indicated no significant differences between the groups on any of the outcomes. The estimated mean difference in maternal nocturnal sleep between the intervention and usual care groups was 5.97 minutes (95% confidence interval −7.55 to 19.5 minutes, P=0.39). No differences in any outcomes were noted based on the specific nurse delivering the intervention or the number of phone contacts received. Conclusion A behavioural-educational intervention delivered in the early postpartum, in hospital, and in the first weeks at home, was ineffective in improving maternal and infant sleep or other health outcomes in the first months postpartum. Trial registration ISRCT No 13501166.

Abstract: Study Objectives: Although currently more affordable than polysomnography, actigraphic sleep estimates have disadvantages. Brand-specific differences in data reduction impede pooling of data in large-scale cohorts and may not fully exploit movement information. Sleep estimate reliability might improve by advanced analyses of three-axial, linear accelerometry data sampled at a high rate, which is now feasible using microelectrome-chanical systems (MEMS). However, it might take some time before these analyses become available. To provide ongoing studies with backward compatibility while already switching from actigraphy to MEMS accelerometry, we designed and validated a method to transform accelerometry data into the traditional actigraphic movement counts, thus allowing for the use of validated algorithms to estimate sleep parameters. Design: Simultaneous actigraphy and MEMS-accelerometry recording. Setting: Home, unrestrained. Participants: Fifteen healthy adults (23-36 y, 10 males, 5 females). Interventions: None. Measurements: Actigraphic movement counts/15-sec and 50-Hz digitized MEMS-accelerometry. Analyses: Passing-Bablok regression optimized transformation of MEMS-accelerometry signals to movement counts. Kappa statistics calculated agreement between individual epochs scored as wake or sleep. Bland-Altman plots evaluated reliability of common sleep variables both between and within actigraphs and MEMS-accelerometers. Results: Agreement between epochs was almost perfect at the low, medium, and high threshold (kappa = 0.87 ± 0.05, 0.85 ± 0.06, and 0.83 ± 0.07). Sleep parameter agreement was better between two MEMS-accelerometers or a MEMS-accelerometer and an actigraph than between two actigraphs. Conclusions: The algorithm allows for continuity of outcome parameters in ongoing actigraphy studies that consider switching to MEMS-accel-erometers. Its implementation makes backward compatibility feasible, while collecting raw data that, in time, could provide better sleep estimates and promote cross-study data pooling.

Abstract: Study Objectives:The algorithms used to derive sleep variables from actigraphy were developed with adults. Because children change position during sleep more often than adults, algorithms may detec...

Abstract: Background Sleep loss produces abnormal increases in reward seeking but the mechanisms underlying this phenomenon are poorly understood. The present study examined the influence of one night of sleep deprivation on neural responses to a monetary reward task in a sample of late adolescents/young adults. Method Using a within-subjects crossover design, 27 healthy, right-handed late adolescents/young adults (16 females, 11 males; mean age 23.1 years) underwent functional magnetic resonance imaging (fMRI) following a night of sleep deprivation and following a night of normal sleep. Participants' recent sleep history was monitored using actigraphy for 1 week prior to each sleep condition. Results Following sleep deprivation, participants exhibited increased activity in the ventral striatum (VS) and reduced deactivation in the medial prefrontal cortex (mPFC) during the winning of monetary reward, relative to the same task following normal sleep conditions. Shorter total sleep time over the five nights before the sleep-deprived testing condition was associated with reduced deactivation in the mPFC during reward. Conclusions These findings support the hypothesis that sleep loss produces aberrant functioning in reward neural circuitry, increasing the salience of positively reinforcing stimuli. Aberrant reward functioning related to insufficient sleep may contribute to the development and maintenance of reward dysfunction-related disorders, such as compulsive gambling, eating, substance abuse and mood disorders

Abstract: Objectives: Evidence for a causal relationship between sleep-loss and metabolism is derived primarily from short-term sleep deprivation studies in the laboratory. The objective of this study was to investigate whether small changes in sleep duration over a three week period while participants are living in their normal environment lead to changes in insulin sensitivity and other metabolic parameters. Methods: Nineteen healthy, young, normal-weight men were randomised to either sleep restriction (habitual bedtime minus 1.5 h) or a control condition (habitual bedtime) for three weeks. Weekly assessments of insulin sensitivity by hyperinsulinaemic-euglycaemic clamp, anthropometry, vascular function, leptin and adiponectin were made. Sleep was assessed continuously using actigraphy and diaries. Results: Assessment of sleep by actigraphy confirmed that the intervention reduced daily sleep duration by 01:19 ± 00:15 (SE; p < 0.001). Sleep restriction led to changes in insulin sensitivity, body weight and plasma concentrations of leptin which varied during the three week period. There was no effect on plasma adiponectin or vascular function. Conclusions: Even minor reductions in sleep duration lead to changes in insulin sensitivity, body weight and other metabolic parameters which vary during the exposure period. Larger and longer longitudinal studies of sleep restriction and sleep extension are warranted. © 2013 Elsevier Inc.

Abstract: The purpose of this study was to examine the nutritional effects on sleep using actigraphy measures. A repeated-measures, counterbalanced, crossover study design was used to administer treatment diets to 44 adult participants. Participants served as their own control and consumed high-protein, high-fat, high-carbohydrate, and control diets. The study participants wore Motionlogger Actigraph sleep watches while consuming weighed food intakes for 4 days over four different treatment periods. Demographic and laboratory data were also analyzed. Actigraph results showed that the wake episodes and sleep latencies were significantly different when comparing the macronutrient intakes of the participants. Post hoc test results showed that high-protein diets were associated with significantly fewer (p = .03) wake episodes and high-carbohydrate diets were associated with significantly shorter (p < .01) sleep latencies than control diets. Thus, consumption of specific macronutrient intakes may have a significant influence on sleep.

Abstract: Study Objectives:To establish the extent to which the developmental changes in sleep timing experienced by Australian adolescents meet the International Classification of Sleep Disorders (ICSD-2) d...

Abstract: The Centers for Disease Control and Prevention Statistics reported that across the last decade, there have been over four million childbirths each year in the United States (Martin et al., 2011). With the birth of each child, new parents are required to adjust to the demands of parenthood. Accordingly, sleep disturbance is commonly experienced among new parents during the early postpartum period, and sleep disturbance is known to have a multitude of adverse effects on health and functioning (see reviews: Alvarez & Ayas, 2004; Copinschi, 2005; Harrison & Horne, 2000). Postpartum sleep disturbance is caused by factors that include infant signaling during nocturnal periods (Nishihara, Horiuchi, Eto, & Uchida, 2000; Nishihara, Horiuchi, Eto, & Uchida, 2001), maternal postpartum endocrine and physiological changes that affect sleep (Manber & Armitage, 1999; Santiago, Nolledo, Kinzler, & Santiago, 2001), and the sleep disturbances experienced by the other bed partner within the postpartum parent dyad (Meijer & vanden Wittenboer, 2007). Sleep within the family system can be interrupted by multiple factors, all of which result in sleep disturbance experienced by both mothers and fathers. Maternal postpartum sleep profiles have been well described (see reviews: Ross, Murray, & Steiner, 2005; Hunter, Rychnovsky, & Yount, 2009). Maternal sleep worsens progressively throughout pregnancy and is most affected, primarily by sleep fragmentation immediately following delivery after which it improves steadily throughout the postpartum period (Shinkoda, Matsumoto, & Park, 1999; Kang, Matsumoto, Shinkoda, Mishima, & Seo, 2002; Rychnovsky & Hunter, 2009; Montgomery-Downs, Insana, Clegg-Kraynok, & Mancini, 2010). Paternal sleep profiles during the postpartum period have been less extensively profiled. Among the existing literature, there are reported changes in postpartum fathers’ sleep from the prenatal to the postpartum period (Condone, Boyce, & Corkindale, 2004). Gay and colleagues reported that both mothers and fathers had less sleep, more self-reported sleep disturbance, and higher ratings of fatigue during the first month postpartum when compared to their levels during the pregnancy period (Gay, Lee, & Lee, 2004). Although postpartum maternal, and to a lesser extent, paternal sleep disturbances are recognized, to date no investigations have objectively quantified the extent of sleepiness, and functional impact of sleep disturbance experienced among postpartum mothers or fathers. The study objective was to fill this void through examination of sleep, sleepiness, fatigue, and neurobehavioral performance among healthy first-time mothers and fathers during their early postpartum period. All values were compared within postpartum couples, and between postpartum and childless control couples.

Abstract: Obstructive sleep apnea (OSA) may be associated with increased energy expenditure (EE) during sleep. As actigraphy is inaccurate at estimating EE from body movement counts alone, we aimed to compare a multiple physiological sensor with polysomnography for determination of sleep and wake, and to test the hypothesis that OSA is associated with increased EE during sleep. We studied 50 adults referred for routine overnight polysomnography. In addition to polysomnography, the SenseWear Pro3 ArmbandTM (Bodymedia Inc.) was placed on the upper right arm. Epoch-by-epoch agreement rate between the measures of sleep versus wake was calculated. Linear regression analyses were performed for EE against apnea–hypopnea index (AHI), 3% oxygen desaturation index (ODI), body mass index (BMI), waist–hip ratio (WHR), gender, age, and average heart rate during sleep. The epoch-by-epoch agreement rate was high (79.9 ± 1.6%) and the ability of the SenseWear to estimate sleep was very good (sensitivity, 88.7 ± 1.5%). However, it was less accurate in determining wake (specificity 49.9 ± 3.6%). Sleep EE was associated with AHI, 3% ODI, BMI, WHR, and male gender (p < 0.001 for all). Stepwise multiple linear regression however revealed that BMI, male gender, age, and average heart rate during sleep were independent predictors of EE (Model R 2 = 0.78). The SenseWear armband provides a reasonable estimation of sleep but a poor estimation of wake. Furthermore, in a selected population of OSA patients, increasing OSA severity is associated with increased EE during sleep, although primarily through an association with increased BMI. However, as our data are not adjusted for fat-free mass and the SenseWear has yet to be validated for EE in OSA patients, these data should be interpreted with caution.