Increased Sleep Onset Latency Research Articles

Sleep Patterns, Pain, and Emotional Functioning in Youth with Inflammatory Bowel Disease.

Youth with inflammatory bowel disease (IBD) may be at increased risk for sleep difficulties due to the painful and inflammatory nature of their disease. Moreover, children and adolescents with IBD experience impairment across a variety of psychosocial domains. However, researchers have yet to investigate the complex interplay between sleep, disease-related symptoms, and psychosocial factors in this population. The purpose of this study was to examine sleep patterns, pain, and mood in pediatric IBD. A sample of 25 children and adolescents with IBD (Mage = 14.24, Range = 10-18 years; 56% male) were recruited from a pediatric gastroenterology clinic. Youth wore an actigraphy watch and completed daily measures of affect and pain over the course of 14 days. Statistical analyses involved repeated measures general estimating equations. No significant association for sleep with negative affect was demonstrated. Despite majority of this sample being in disease remission, results revealed that increased sleep onset latency was associated with presence of next day pain and pain was associated with better next night sleep efficiency. Findings of the current study suggest youth with IBD experience poor sleep quality, which is significantly related to the pain they experience. Consequently, healthcare providers should screen for and address sleep quality to optimize outcomes in their pediatric patients. Objectively assessing sleep patterns (e.g., actigraphy) may prove useful for pediatric IBD samples; however, additional research is needed to determine actigraphy's feasibility and efficacy in assessing sleep patterns in real world settings (e.g., pediatric medical clinics).

Analysis on the Application of Exercise in Resolving Increased Sleep-Onset Latency

As insufficient sleep has been coined a “public health epidemic” by the U.S Centers for Disease Control and Prevention (CDC), interventions should be executed as to ease the global crisis. Currently, considerable accounts of research have been done using various outcome measures as to help put a stop to the health crisis. Moreover, a decrease in sleep quality and times is often times caused by the delay in overall sleep-onset latency. Exercise and sleep are thought to be interconnected, however, uncertainty is present around the debate of whether or not exercise may affect sleep-onset latency. This article examines the various accounts of research done on the topic by analyzing current studies through literature review, attempting to form a comprehensive and thorough conclusion based on current findings, while simultaneously introducing the severity, background and biological basis behind the issue to provide further insight on the correlation between exercise and sleep-onset latency. However, conflicting results and conclusions were found, most likely due to multivariate aims, creating a variety of contrasting variables such as differing demographics, settings, and outcome measures. Nonetheless, through compilation of various sources, new insight can be made regarding how an increase in sleep-onset latency can be combated with consideration of definitive demographics and settings. Moreover, while a generalization can not be made based on the research conducted in this article, exercise can still be utilized and applied in specific circumstances.

O050 The Dose and Timing Relationship between Caffeine and Subsequent Sleep

Abstract Introduction There is currently a lack of evidence to guide recommendations for the consumption of caffeine to mitigate its effects on sleep. Therefore, the aim of this study was to investigate the effect of caffeine dose and timing combinations on subsequent sleep. Methods Twenty-three healthy adult males with a moderate habitual caffeine intake (<300mg/d) participated in a randomised, repeated-measures study. Participants completed seven conditions, including a placebo and two caffeine doses (100mg and 400mg) consumed at three different time points (12, eight, and four hours prior to habitual bedtime) with a 48-hour washout period. Sleep was measured using in-home partial polysomnography and subjective sleep diaries. Linear mixed effects models were used to estimate the effect of each caffeine condition on sleep characteristics. Results Caffeine negatively impacted sleep when compared to the placebo. The largest impact was observed when the highest dose of caffeine (400mg) was consumed closest to bedtime, with a 54.0 minute reduction in total sleep time (p=<0.001), a 10.2% reduction in sleep efficiency (p= <0.001), a 14.4 minute increase in sleep onset latency (p=0.047), a 25.3 minute increase in wake after sleep onset (p=<0.001), a 5.5% increase in the proportion of light sleep (N1&N2)(p=0.029), and a 4.55% reduction in deep sleep (N3)(p=0.026). Discussion The largest decrements in sleep occurred when caffeine was consumed at a high dose in close proximity to bedtime. These findings highlight the importance of considering the amount and timing of caffeine intake when aiming to minimise the effect of caffeine on subsequent sleep.

First-night effect in insomnia disorder: a systematic review and meta-analysis of polysomnographic findings.

Polysomnographic studies have been performed to investigate the first-night effect in insomnia disorder. However, these studies have revealed discrepant findings. This meta-analysis aimed to summarise and quantify the characteristics of the first-night effect in insomnia disorder. We performed a systematic search of the PubMed, Medline, EMBASE, Web of Science and PsycINFO databases to identify studies published through October 2019. A total of 11,862 articles were identified, and seven studies with eight independent populations were included in the meta-analysis. A total of 639 patients with insomnia disorder and 171 healthy controls underwent more than 2 consecutive nights of in-laboratory polysomnography. Pooled results demonstrated that both variables of sleep continuity and sleep architecture, other than slow-wave sleep were significantly altered in the first-night effect in insomnia disorder. Furthermore, the results indicated that patients with insomnia disorder had a disruption of sleep continuity in the first-night effect, including increased sleep onset latency and reduced total sleep time, compared to healthy controls. Overall, the findings show that patients with insomnia disorder experience the first-night effect, rather than reverse first-night effect, and the profiles of the first-night effect in patients with insomnia are different from healthy controls. These indicate that an adaptation night is necessary when sleep continuity and sleep architecture is to be studied in patients with insomnia disorder. More well-designed studies with large samples are needed to confirm the results.

Impact of sleep chronotype on in-laboratory polysomnography parameters.

Morningness-eveningness preference, also known as chronotype, is the tendency for a person to sleep during certain hours of the day and is broadly categorised into morning and evening types. In-laboratory polysomnography (iPSG) is the gold-standard to assess sleep, however, an individual's chronotype is not accounted for in current protocols, which may confound collected sleep data. The objective of our study was to assess if chronotype had an association with sleep physiology. Patients who completed the diagnostic iPSG and the Morningness-Eveningness Questionnaire (MEQ), which categorises patients into morning type, neither or evening type, were assessed. Multivariable linear regression models were used to assess if chronotype was associated with sleep quality, duration, and physiology during iPSG. The study sample included 2612 patients (mean age of 53.6 years, 48% male) recruited during 2010-2015. Morning type, compared with neither type, was significantly associated with an increase in total sleep time and rapid eye movement (REM) sleep, and a decrease in sleep onset latency and the arousal index. Evening type, compared with neither type, was significantly associated with a decrease in total sleep time, sleep efficiency, and REM sleep, and an increase in sleep onset latency and wake after sleep onset. Additionally, iPSG lights out time was significantly different between the different chronotypes. Overall, a morningness chronotype was associated with favourable sleep quality and duration while an eveningness chronotype was associated with reduced sleep quality. Our study quantifies the association of chronotype with iPSG metrics and suggests that laboratory protocols should consider chronotype in their evaluations.

Sleep profile in a population of community‐dwelling nonagenarians: data from the Mugello study

Very few studies have investigated sleep characteristics in the oldest-old individuals (aged ≥85 years) and data collected often rely on self-reported information. This study had three aims: (i) to objectively assess, using a wearable device, the sleep characteristics of a large community of oldest-old subjects; (ii) to assess differences in sleep parameters between self-reported 'good sleepers' and 'bad sleepers'; (iii) to assess whether there was a relationship between sleep parameters and cognitive status in this community-dwelling population. There were 178 subjects (74.2% women, median age 92 years) included in the 'Mugello study', who wore an armband 24 h/day for at least two consecutive nights to estimate sleep parameters. The perceived sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), the cognitive status through the Mini-Mental State Examination. Continuous variables were compared between men/women, and good/bad sleepers with the independent t-test or Mann-Whitney U-test, according to data distribution. Chi-square test was used for categorical/dichotomous variables. An ordinal logistic regression model was used to study the possible association between sleep parameters and cognitive function. Participants spent in bed nearly 9 h, with a total sleep time of 7 h, a sleep onset latency of 17 min, and a sleep efficiency of 83%. Sleep onset latency was significantly associated with different cognitive levels when age and education level were considered. No significant difference in sleep parameters estimated using the SenseWear armband were found between poor (n= 136, 76.4%) and good sleepers (n= 42, 23.6%), identified according to the PSQI. In this study, actigraphic measurements revealed that subjects with a cognitive decline were more prone to increased sleep onset latency. Sleep quality assessed using the PSQI was not coherent with actigraphic measurements in this sample, supporting the need for objective measures when investigating sleep quality in the oldest-old population.

Evaluation of sleep and therapeutic education needs of military with PTSD

Sleep disorders in post-traumatic stress disorder (PTSD) are both diagnostic (nocturnal reliving) and prognostic. Poor sleep worsens the daytime symptomatology of PTSD and makes it resistant to treatment. However, no specific treatment is codified in France to treat these sleep disorders although sleep therapies (cognitive behavioural therapy for insomnia, psychoeducation and relaxation) have proven for years to be effective in treating insomnia. Therapeutic sessions can be part of a therapeutic patient education program, which is a model for the management of chronic pathologies. It allows for an improvement in a patient's quality of life and enhanced medication compliance. We therefore carried out an inventory of sleep disorders of patients with PTSD. First, we collected data by means of sleep diaries concerning the population's sleep disorders at home. Then we assessed the population's expectations and needs regarding its management of sleep, thanks to a semi-qualitative interview. The data from sleep diaries, which was consistent with the literature, showed that our patients suffered from severe sleep disorders that strongly impact their daily lives, with 87% of patients having an increased sleep onset latency, and 88% having nightmares. We observed a strong demand from patients for specific support for these symptoms, 91% expressing an interest in a TPE program targeting sleep disorders. Thanks to the data collected, the emerging themes for a future therapeutic patient education program targeting sleep disorders of soldiers with PTSD are: sleep hygiene; management of nocturnal awakenings, including nightmares; and psychotropic drugs.

Excessive daytime sleepiness in a model of Parkinson’s disease improved by low-frequency stimulation of the pedunculopontine nucleus

Patients with Parkinson’s disease often complain of excessive daytime sleepiness which negatively impacts their quality of life. The pedunculopontine nucleus, proposed as a target for deep brain stimulation to improve freezing of gait in Parkinson’s disease, is also known to play a key role in the arousal system. Thus, the putative control of excessive daytime sleepiness by pedunculopontine nucleus area stimulation merits exploration for treating Parkinson’s disease patients. To this end, two adult nonhuman primates (macaca fascicularis) received a deep brain stimulation electrode implanted into the pedunculopontine nucleus area along with a polysomnographic equipment. Stimulation at low frequencies and high frequencies was studied, in healthy and then MPTP-treated nonhuman primates. Here, we observed that MPTP-treated nonhuman primates suffered from excessive daytime sleepiness and that low-frequency stimulation of the pedunculopontine nucleus area was effective in reducing daytime sleepiness. Indeed, low-frequency stimulation of the pedunculopontine nucleus area induced a significant increase in sleep onset latency, longer continuous periods of wakefulness and thus, a partially restored daytime wake architecture. These findings may contribute to the development of new therapeutic strategies in patients suffering from excessive daytime sleepiness.

The impact of COVID-19 on the daily lives and study habits of the MBBS students

Introduction: COVID-19 pandemic has significantly impacted the academic and personal life of all college students.However, it has had a more profound impact on medical undergraduates. Objectives: 1) Survey of changes in the daily routine,views about their career and study habits of the MBBS students 2) To document changes in eating habits, other health-related habits, and self-perception of body image Methods: Permission of Institutional Ethics Committee (IEC) was obtained. An online observational cross-sectional study was conducted, using an online Google Docs-based questionnaire; circulated among MBBS students of all years, studying in 12 medical colleges both government and private medical institutions of India via WhatsApp. Results: We observed an increase in sleeping hours in 75.1% of students, an increase in sleep onset latency (62.6%),and difficulty maintaining sleep (38.3%). About 67.1% of students reported dedicating more hours to their hobbies, and 71.1% reported a decrease in time spent studying throughout the lockdown. We even observed contrasting responses towards the pandemic wherein 50.3% of the students wanted to volunteer and join the workforce while 37% were worried about the situation becoming worse. The frequency of meals and snacking in between meals had increased. Binge eating habits were noticed in around 13% on a daily basis. As a means to cope with this overeating, around 11% of students used laxatives and induced vomiting. Students also reported medical problems like fluctuations in weight, stomach cramps, syncope, and fatigue. Conclusion: Significant disturbances were observed in the daily routine, eating habits, and study habits of medical students, which had perhaps led to bigger perplexities of career-related uncertainty and improper coping techniques of varying degrees.These can have a nationwide impact on our health care system, stressing the need to strengthen its budding doctors to make them healthier and more resilient for the future

Basal Ganglia Local Field Potentials as a Potential Biomarker for Sleep Disturbance in Parkinson's Disease.

Sleep disturbances, specifically decreases in total sleep time and sleep efficiency as well as increased sleep onset latency and wakefulness after sleep onset, are highly prevalent in patients with Parkinson's disease (PD). Impairment of sleep significantly and adversely impacts several comorbidities in this patient population, including cognition, mood, and quality of life. Sleep disturbances and other non-motor symptoms of PD have come to the fore as the effectiveness of advanced therapies such as deep brain stimulation (DBS) optimally manage the motor symptoms. Although some studies have suggested that DBS provides benefit for sleep disturbances in PD, the mechanisms by which this might occur, as well as the optimal stimulation parameters for treating sleep dysfunction, remain unknown. In patients treated with DBS, electrophysiologic recording from the stimulating electrode, in the form of local field potentials (LFPs), has led to the identification of several findings associated with both motor and non-motor symptoms including sleep. For example, beta frequency (13–30 Hz) oscillations are associated with worsened bradykinesia while awake and decrease during non-rapid eye movement sleep. LFP investigation of sleep has largely focused on the subthalamic nucleus (STN), though corresponding oscillatory activity has been found in the globus pallidus internus (GPi) and thalamus as well. LFPs are increasingly being recognized as a potential biomarker for sleep states in PD, which may allow for closed-loop optimization of DBS parameters to treat sleep disturbances in this population. In this review, we discuss the relationship between LFP oscillations in STN and the sleep architecture of PD patients, current trends in utilizing DBS to treat sleep disturbance, and future directions for research. In particular, we highlight the capability of novel technologies to capture and record LFP data in vivo, while patients continue therapeutic stimulation for motor symptoms. These technological advances may soon allow for real-time adaptive stimulation to treat sleep disturbances.

Internet Addiction and Sleep Problems among Russian Adolescents: A Field School-Based Study.

This study aims to establish a link between disturbances in the night sleep habitus, quality of sleep, and daytime sleepiness in adolescents with Internet addiction and different types of content consumed. Methods: This is a cross-sectional observational study of a school sample in three large cities in Central Siberia. 4615 schoolchildren of 12–18 years old were examined. The Russian-language versions of the Chen Internet Addiction Scale, the Game Addiction Scale for Adolescents, and the Social Media Disorder Scale were used to identify Internet addiction. Questions from the Pittsburgh Sleep Quality Index questionnaire were used to assess nighttime sleep. Daytime sleepiness was assessed using the Pediatric Daytime Sleepiness Scale questionnaire. Results: Adolescents with Internet addiction go to bed and wake up late; they are characterized by a decrease in the duration of nighttime sleep, an increase in sleep onset latency, and frequent nighttime awakenings, as well as more pronounced daytime sleepiness. Among the sleep parameters studied, the indicators of daytime sleepiness and night awakening scales have the highest effect size in Internet-addicted adolescents, regardless of the media consumed. Conclusion: Internet-addicted adolescents are characterized by significant disturbances in the quality of nighttime sleep and excessive daytime sleepiness, which requires appropriate psychological correction.

Relationships Among Sleep Disturbance, Reward System Functioning, Anhedonia, and Depressive Symptoms

Recent models propose reward system dysfunction as a key mediator of the relationship between sleep and depression and anhedonia. This study explored interrelationships among sleep disturbance, depressive symptoms, anhedonia, and reward responsiveness. Two-hundred and sixty undergraduate students completed questionnaires and a daily diary paradigm assessing sleep, reward responsiveness, depression, anhedonia, and positive affect over 1 week. Baseline sleep disturbance was associated with depressive symptoms, anhedonia, and reward responsiveness. Daily diary sleep parameters showed differential associations with anticipatory versus consummatory reward responsiveness and positive affect. Poorer sleep quality, shorter sleep duration, and longer awakening after sleep onset predicted blunted anticipatory and consummatory reward responsiveness, while increased sleep onset latency and lower sleep efficiency predicted only decreased consummatory reward responsiveness. All sleep indices, except sleep onset latency, were associated with positive affect. Findings demonstrate unique associations between disparate sleep disturbance and reward responsiveness elements, highlighting new treatment mechanisms for anhedonia and depression.

The Impact of Television, Electronic Games, and Social Technology Use on Sleep and Health in Adolescents with an Evening Circadian Preference.

There are mixed findings when examining if technology use is harmful for adolescent sleep and health. This study builds on these mixed findings by examining the association between technology use with sleep and health in a high-risk group of adolescents. Adolescents with an evening circadian preference (N = 176; 58% female, mean age = 14.77, age range = 10-18) completed measures over one week. Sleep was measured via actigraphy. Technology use and health were measured using ecological momentary assessment. Technology use was associated with an increase in sleep onset latency; with better emotional, social, cognitive, and physical health; and with worse behavioral health. This study offers support for technology use having some benefits and expands research on technology use to adolescents with an evening circadian preference.

Chapter 24 - Chronotherapy

The objective of chronotherapy is to optimize medical treatments taking into account the body's circadian rhythms. Chronotherapy is referred to and practiced in two different ways: (1) to alter the sleep-wake rhythms of patients to improve the sequels of several pathologies; (2) to take into account the circadian rhythms of patients to improve therapeutics. Even minor dysfunction of the biological clock can greatly affect sleep/wake physiology causing excessive diurnal somnolence, increase in sleep onset latency, phase delays or advances in sleep onset, frequent night awakenings, reduced sleep efficiency, delayed and shortened rapid eye movement sleep, or increased periodic leg movements. Chronotherapy aims to restore the proper circadian pattern of the sleep-wake cycle, through adequate sleep hygiene, timed light exposure, and the use of chronobiotic medications, such as melatonin, that affect the output phase of circadian rhythms, thus controlling the clock. Concerning the second use of chronotherapy, therapeutic outcomes as diverse as the survival after open-heart surgery or the efficacy and tolerance to chemotherapy vary according to the time of day. However, humans are heterogeneous concerning the timing of their internal clocks. Not only different chronotypes exist but also the endogenous human circadian period (τ) is not a stable trait as it depends on many internal and external factors. If any scheduled therapeutic intervention is going to be optimized, a tool is needed for simple diagnostic and objectively measurement of an individual's internal time at any given time. Methodologic advances like the use of single-sample gene expression and metabolomics are discussed.

How do children with drug-resistant epilepsy sleep? A clinical and video-PSG study

AimThe aim of this study was to assess sleep architecture and sleep problems among three homogenous groups of children including children with drug-resistant focal epilepsy, children with newly diagnosed, drug-naïve focal epilepsy, and healthy children using overnight video-polysomnography (V-PSG) and a sleep questionnaire. MethodsWe compared sleep architecture among 44 children with drug-resistant focal epilepsy, 41 children with newly diagnosed, drug naïve focal epilepsy, and 36 healthy children. All children underwent an overnight V-PSG recording, and their parents completed the Children's Sleep Habits Questionnaire (CSHQ). Sleep recordings were scored according to the American Academy of Sleep Medicine criteria. ResultsCompared with children with newly diagnosed epilepsy and healthy controls, children with drug-resistant epilepsy receiving antiepileptic treatment showed disturbed sleep architecture, a significant reduction in time in bed, total sleep time, sleep efficiency, NREM3%, REM%, and a significant increase in awakenings, wake after sleep onset, and periodic leg movement. Children with drug-naïve, newly diagnosed focal epilepsy showed a statistically significant increase in sleep onset latency, rapid eye movement (REM) latency, N1%, awakenings, and a significant decrease in time in bed when compared with the controls. Children with drug-resistant epilepsy had the highest CSHQ total scores, while children with drug-naïve, newly diagnosed focal epilepsy had higher scores than healthy children. ConclusionThis is one of the few polysomnographic studies adding to the limited research on the sleep macrostructure of children with drug-resistant epilepsy compared with children with drug-naïve, newly diagnosed focal epilepsy and healthy children by obtaining objective measurements of sleep concurrently with a validated questionnaire. Children with drug-resistant epilepsy had a greater incidence of sleep disturbance on the basis of qualitative aspects and architecture of sleep than children with newly diagnosed epilepsy, suggesting the need for referral of children with drug-resistant epilepsy for overnight sleep evaluation in order to improve the clinical management and optimize therapeutic strategies.

Associations of Sleep Measures with Retinal Microvascular Diameters among Police Officers

ABSTRACT Purpose We examined cross-sectional associations of sleep measures with central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE) and investigated whether sex and race/ethnicity modified these associations. Methods Participants (N = 202; 78% white; 71% men) were enrolled in the Buffalo Cardio-metabolic Occupational Police Stress study (2011–2014). Wrist actigraphy was used to assess sleep measures including sleep duration, sleep efficiency, sleep onset latency, wake after sleep onset, number of awakenings, and longest wake episode. CRAE and CRVE were obtained from fundus photography of retina and were averaged from both eyes per officer. Results We observed significant associations between sleep efficiency and CRVE (β = -2.81 µm; P= .046), and between longest wake episode and CRVE (β = 3.24 µm; P= .021). Adjustments for demographics, lifestyles, and physical and psychological factors attenuated these associations. Sex modified the independent associations of sleep onset latency and longest wake episode with CRVE. One standard deviation (SD) increase in sleep onset latency was associated with 4.81 µm larger CRVE (P= .028) (P-interaction = 0.098), and one SD increase in longest wake episode was associated with 4.62 µm larger CRVE (P= .032) (P-interaction = 0.115) among men. Race/ethnicity also modified the association between longest wake episode and CRVE (P-interaction = 0.088). A significant association was observed only among white officers (β = 4.96 µm; P= .025). Conclusions We found that poor sleep quality, measured by longest wake episode, was positively and independently associated with retinal venular diameter among white and male officers. Longitudinal studies are warranted to assess whether poor sleep quality is a risk factor for retinal diameter changes.

0831 Hot Flashes and Insomnia Throughout the Life Span of Women from the Episono Cohort

Abstract Introduction Hormonal changes may trigger sleep disturbances in women. Insomnia affects one in every three-to-four of them, most likely during pre to post menopause, and especially in association with hot flashes. Thus, the present study aimed to investigate the occurrence of hot flashes among women with and without insomnia and on different reproductive stages. Methods Sampling procedure was a three-stage clustering of the population of Sao Paulo, Brazil according to gender, age (20-80 years), and socio-economic status. A total of 574 women were interviewed, underwent polysomnographic recording (PSG), and had fasting-blood samples collected. Hormone levels and a gynecological questionnaire were used to classify reproductive stages. Premenopausal women were classified either in the follicular, luteal, or periovulatory stage or as anovulatory or under hormonal contraceptives; whereas those menopausal were classified in perimenopause or in early or late stages. Individuals reporting frequent and persistent insomnia symptoms accompanied by relevant daytime impairment were classified with insomnia syndrome. Objective insomnia was defined by increased sleep onset latency and/or awake after sleep onset, decreasing sleep duration. Results The final sample included 550 women, representing 53% of the EPISONO cohort (n=1,042). Hot flashes were reported by 9% of the premenopausal women (n=339) and by 42% of the menopausal. Complaints were more frequent among women in perimenopause (67%) and those in use of hormonal therapy (60%), and it tended to decrease in later stages (33%); whereas before menopause, hot flashes were especially reported by anovulatory women (26%), while significantly less by those using contraceptives (6%). Hot flashes were associated with a 2-fold increase in insomnia symptoms and while it predicted objective sleep alterations among premenopausal women, they did not after menopause, when alterations in sleep were better explained by an effect of aging. Conclusion Our current findings suggest that hot flashes are associated with irregular menstrual cycles among premenopausal women, and particularly with early stages of menopause, predicting both subjective and objective sleep alterations. Support This research was supported by fellowships from Associação Fundo de Incentivo à Pesquisa (AFIP) and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) - Finance Code 001.

Changes in dietary inflammatory potential predict changes in sleep quality metrics, but not sleep duration.

Non-pharmacological sleep interventions may improve sleep profiles without the side-effects observed with many pharmacological sleep aids. The objective of this research was to examine the association between sleep and inflammation and to examine how changes in dietary inflammatory potential influence changes in sleep. The Inflammation Management Intervention Study (IMAGINE), which was a dietary intervention designed to lower inflammation, provided access to 24-h dietary recalls (24HR), objectively measured sleep using SensewearTM armbands, and a range of self-reported demographics, health histories, lifestyle behaviors, psychosocial metrics, anthropometric measurements, and inflammatory biomarkers. Dietary Inflammatory Index® (DII®) scores were calculated from three unannounced 24HR-derived estimated intakes of whole foods and micro and macronutrients over a 2-week period at baseline and post-intervention (i.e. month 3). Statistical analyses primarily utilized linear regression. At baseline, for every 1-min increase in sleep onset latency, tumor necrosis factor-α increased by 0.015 pg/mL (±0.008, p = 0.05). Every one-percentage increase in sleep efficiency was associated with decreased C-reactive protein (CRP) of -0.088 mg/L (±0.032, p = 0.01). Every 1-min increase in wake-after-sleep-onset (WASO) increased both CRP and interleukin-6. Compared to participants with pro-inflammatory DII changes over 3 months, those with anti-inflammatory changes decreased WASO (0 vs. -25 min, respectively, p < 0.01) and improved sleep efficiency (-2.1% vs. +2.6%, respectively, p = 0.04). Non-pharmacological treatments, such as anti-inflammatory diets, may improve sleep in some adults. Future research involving dietary treatments to improve sleep should not only focus on the general population, but also in those commonly experiencing co-morbid sleep complaints. NCT02382458.

Associations of objectively measured sleep characteristics and incident hypertension among police officers: The role of obesity.

This study investigated the associations of baseline sleep onset latency, wake after sleep onset, longest wake episode, number of awakenings, sleep efficiency and sleep duration with incident hypertension during a 7-year follow-up (n=161, 68% men) and the joint effect of insufficient sleep and obesity on incident hypertension. Sleep parameters were derived from 15-day actigraphy data. Relative risks and 95% confidence intervals were estimated using a robust Poisson regression model. Each 10-min increase in sleep onset latency was associated with an 89% higher risk of hypertension (95% confidence interval [CI]=1.12-3.20). Each 10-min increase in longest wake episode was associated with a 23% higher risk of hypertension (95% CI=1.01-1.50) and each 10% decrease in sleep efficiency was associated with a 50% higher risk of hypertension (95% CI=1.02-2.22). These associations were independent of demographic and lifestyle characteristics, depressive symptoms, shift work, sleep duration and body mass index. Having <6hr of sleep and a body mass index ≥30kg/m2 increased the risk of hypertension (relative risk=2.81; 95% CI=1.26-6.25) compared with having ≥6hr of sleep and a body mass index <30 after controlling for confounders. Relative excess risk due to interaction was 3.49 (95% CI=-1.69-8.68) and ratio of relative risk was 3.21 (95% CI=0.72-14.26). These results suggest that poor sleep quality is a risk factor for hypertension. Longitudinal studies with larger sample sizes are warranted to examine the joint effect of insufficient sleep and obesity on development of hypertension.

Lying Awake at Night: Cardiac Autonomic Activity in Relation to Sleep Onset and Maintenance

Insomnia, i.e., difficulties initiating and/or maintaining sleep, is one of the most common sleep disorders. To study underlying mechanisms for insomnia, we studied autonomic activity changes around sleep onset in participants without clinical insomnia but with varying problems with initiating or maintaining sleep quantified as increased sleep onset latency (SOL) and wake after sleep onset (WASO), respectively. Polysomnography and electrocardiography were simultaneously recorded in 176 participants during a single night. Cardiac autonomic activity was assessed using frequency domain analysis of RR intervals and results show that the normalized spectral power in the low frequency band (LFnu) after sleep onset was significantly higher in participants with long SOL compared to participants with short SOL. Furthermore, the normalized spectral power in the high frequency band (HFnu) was significantly lower in participants with long SOL as compared to participants with short SOL over 3 time periods (first 10 min in bed intending to sleep, 10 min before, and 10 min after sleep onset). These results suggest that participants with long SOL are more aroused in all three examined time periods when compared to participants with short SOL, especially for young adults (20–40 years). As there is no clear consensus on the cutoff for an increased WASO, we used a data-driven approach to explore different cutoffs to define short WASO and long WASO groups. LFnu, HFnu, and LF/HF differed between the long and the short WASO groups. A higher LFnu and LF/HF and a lower HFnu was observed in participants with long WASO for most cutoffs. The highest effect size was found using the cutoff of 66 min. Our findings suggest that autonomic cardiac activity has predictive value with respect to sleep characteristics pertaining to sleep onset and maintenance.