A preliminary study of slow-wave EEG activity and insulin sensitivity in adolescents

Association of Disrupted Delta Wave Activity During Sleep With Long-Term Cardiovascular Disease and Mortality

BACKGROUND

Delta wave activity is a prominent feature of deep sleep, which is significantly associated with sleep quality.

OBJECTIVES

The authors hypothesized that delta wave activity disruption during sleep could predict long-term cardiovascular disease (CVD) and CVD mortality risk.

METHODS

The authors used a comprehensive power spectral entropy-based method to assess delta wave activity during sleep based on overnight polysomnograms in 4,058 participants in the SHHS (Sleep Heart Health Study) and 2,193 participants in the MrOS (Osteoporotic Fractures in Men Study) Sleep study.

RESULTS

During 11.0 ± 2.8 years of follow-up in SHHS, 729 participants had incident CVD and 192 participants died due to CVD. During 15.5 ± 4.4 years of follow-up in MrOS, 547 participants had incident CVD, and 391 died due to CVD. In multivariable Cox regression models, lower delta wave entropy during sleep was associated with higher risk of coronary heart disease (SHHS: HR: 1.46; 95% CI: 1.02-2.06; P = 0.03; MrOS: HR: 1.79; 95% CI: 1.17-2.73; P < 0.01), CVD (SHHS: HR: 1.60; 95% CI: 1.21-2.11; P < 0.01; MrOS: HR: 1.43; 95% CI: 1.00-2.05; P = 0.05), and CVD mortality (SHHS: HR: 1.94; 95% CI: 1.18-3.18; P < 0.01; MrOS: HR: 1.66; 95% CI: 1.12-2.47; P = 0.01) after adjusting for covariates. The Shapley Additive Explanations method indicates that low delta wave entropy was more predictive of coronary heart disease, CVD, and CVD mortality risks than conventional sleep parameters.

CONCLUSIONS

The results suggest that delta wave activity disruption during sleep may be a useful metric to identify those at increased risk for CVD and CVD mortality.

Associations of Slow-Wave Sleep With Prevalent and Incident Type 2 Diabetes in the Multi-Ethnic Study of Atherosclerosis

CONTEXT

N3 sleep (i.e., slow-wave sleep), a marker of deep restorative sleep, is implicated in hormonal and blood pressure regulation and may impact cardiometabolic health.

OBJECTIVE

We conducted cross-sectional and prospective analyses to test whether a higher proportion and longer duration of N3 sleep are associated with reduced type 2 diabetes risk.

METHODS

A subsample of participants from the Multi-Ethnic Study of Atherosclerosis completed 1-night polysomnography at Exam 5 (2010-2013) and were prospectively followed until Exam 6 (2016-2018). We used modified Poisson regression to examine the cross-sectional associations of N3 proportion and duration with prevalent diabetes and Cox proportional hazards models to estimate risk of diabetes according to N3 measures.

RESULTS

In cross-sectional analyses (n = 2026, mean age: 69 years), diabetes prevalence was 28% (n = 572). Compared with the first quartile (Q1) of the N3 proportion (<2.0%), participants in Q4 (≥15.4%) were 29% (95% CI 0.58, 0.87) less likely to have prevalent diabetes (P trend = .0016). The association attenuated after adjustment for demographics, lifestyles, and sleep-related factors (P trend = .3322). In prospective analyses of 1251 participants and 129 incident cases over 6346 person-years of follow-up, a curvilinear relationship was observed between N3 proportion and incident diabetes risk. In the fully adjusted model, the hazard ratio (95% CI) of developing diabetes vs Q1 was 0.47 (0.26, 0.87) for Q2, 0.34 (0.15, 0.77) for Q3, and 0.32 (0.10, 0.97) for Q4 (P nonlinearity = .0213). The results were similar for N3 duration.

CONCLUSION

Higher N3 proportion and longer N3 duration were prospectively associated with lower type 2 diabetes risk in a nonlinear fashion among older American adults.

Effectiveness of cognitive behavior therapy for sleep disturbance and glycemic control in persons with type 2 diabetes mellitus: A community-based randomized controlled trial in China

BACKGROUND

Poor sleep quality is a common clinical feature in patients with type 2 diabetes mellitus (T2DM), and often negatively related with glycemic control. Cognitive behavioral therapy (CBT) may improve sleep quality and reduce blood sugar levels in patients with T2DM. However, it is not entirely clear whether CBT delivered by general practitioners is effective for poor sleep quality in T2DM patients in community settings.

AIM

To test the effect of CBT delivered by general practitioners in improving sleep quality and reducing glycemic levels in patients with T2DM in community.

METHODS

A cluster randomized controlled trial was conducted from September 2018 to October 2019 in communities of China. Overall 1033 persons with T2DM and poor sleep quality received CBT plus usual care or usual care. Glycosylated hemoglobin A1c (HbAlc) and sleep quality [Pittsburgh Sleep Quality Index (PSQI)] were assessed. Repeated measures analysis of variance and generalized linear mixed effects models were used to estimate the intervention effects on hemoglobin A1c and sleep quality.

RESULTS

The CBT group had 0.64, 0.50, and 0.9 lower PSQI scores than the control group at 2 mo, 6 mo, and 12 mo, respectively. The CBT group showed 0.17 and 0.43 lower HbAlc values than the control group at 6 mo and 12 mo. The intervention on mean ΔHbAlc values was significant at 12 mo (t = 3.68, P < 0.01) and that mean ΔPSQI scores were closely related to ΔHbAlc values (t = 7.02, P < 0.01). Intention-to-treat analysis for primary and secondary outcomes showed identical results with completed samples. No adverse events were reported.

CONCLUSION

CBT delivered by general practitioners, as an effective and practical method, could reduce glycemic levels and improve sleep quality for patients with T2DM in community.

Inadequate sleep as a contributor to impaired glucose tolerance: A cross-sectional study in children, adolescents, and young adults with circadian rhythm sleep-wake disorder

BACKGROUND

Sleep deprivation and circadian disruption are associated with decreased insulin sensitivity and hyperglycemia. It is uncertain whether circadian sleep-wake disorder (CRSWD), which relates to both the homeostatic sleep system and the circadian timing system, affects glycemic regulation and insulin secretion. We aimed to examine the associations among sleep duration, sleep architecture or circadian rhythm of the sleep-wake cycle, and glucose metabolism in children, adolescents, and young adults with CRSWD.

METHODS

This cross-sectional observational study of 124 patients with CRSWD took place at Hyogo Children's Sleep and Development Medical Research Center in Hyogo, Japan. The patients underwent a 3-hour oral glucose tolerance test, anthropometric measurements, sleep-log analyses, and polysomnography. Analysis of covariance models were used to assess the association between sleep architecture or circadian rhythm of sleep-wake cycle and glucose/insulin homeostasis, adjusted for confounding variables such as age, gender, standardized body mass index, and sleep apnea index.

RESULTS

Impaired glucose tolerance was detected in 25.8% of all patients with CRSWD. After adjustment for confounding variables, we found a negative association between total sleep time (TST) and the 2-hour plasma glucose level. Stage N1 (%TST) was also a significant predictor of 3-hour glucose level. However, we did not detect an association between circadian rhythm of the sleep-wake cycle and glucose/insulin measures.

CONCLUSIONS

Decreased sleep duration and increased stage N1 (%TST) were associated with hyperglycemia in patients with CRSWD. Further research should elucidate how circadian misalignment in patients with CRSWD is associated with glucose and insulin homeostasis.

Objective Sleep Characteristics and Cardiometabolic Health in Young Adolescents

: media-1vid110.1542/5778442247001PEDS-VA_2017-4085Video Abstract BACKGROUND AND OBJECTIVES: Shorter sleep duration is associated with childhood obesity. Few studies measure sleep quantity and quality objectively or examine cardiometabolic biomarkers other than obesity.

METHODS

This cross-sectional study of 829 adolescents derived sleep duration, efficiency and moderate-to-vigorous physical activity from >5 days of wrist actigraphy recording for >10 hours/day. The main outcome was a metabolic risk score (mean of 5 sex-specific z-scores for waist circumference, systolic blood pressure, high-density lipoprotein cholesterol scaled inversely, and log-transformed triglycerides and homeostatic model assessment of insulin resistance), for which higher scores indicate greater metabolic risk. Secondary outcomes included score components and dual-energy radiograph absorptiometry fat mass. We measured socioeconomic status, race and/or ethnicity, pubertal status, and obesity-related behaviors (television-viewing and fast food and sugar-sweetened beverage consumption) using questionnaires.

RESULTS

The sample was 51.5% girls; mean (SD) age 13.2 (0.9) years, median (interquartile range) sleep duration was 441.1 (54.8) minutes per day and sleep efficiency was 84.0% (6.3). Longer sleep duration was associated with lower metabolic risk scores (-0.11 points; 95% CI: -0.19 to -0.02, per interquartile range). Associations with sleep efficiency were similar and persisted after adjustment for BMI z score and physical activity, television-viewing, and diet quality. Longer sleep duration and greater sleep efficiency were also favorably associated with waist circumference, systolic blood pressure, high-density lipoprotein cholesterol, and fat mass.

CONCLUSIONS

Longer sleep duration and higher sleep efficiency were associated with a more favorable cardiometabolic profile in early adolescence, independent of other obesity-related behaviors. These results support the need to assess the role of sleep quantity and quality interventions as strategies for improving cardiovascular risk profiles of adolescents.

Self-reported nocturnal sleep duration and glycosylated hemoglobin A in the Study of Cardiovascular Risks in Adolescents (ERICA)

OBJECTIVE

At present, epidemiologic studies regarding the relationship between sleep duration and glucose metabolism in adolescents are scarce. The objective was to investigate the association between self-reported nocturnal sleep duration and glycosylated hemoglobin A in 12- to 17-year-old Brazilian adolescents.

PATIENTS/METHODS

A school-based multicenter cross-sectional study was carried out in private and public schools from 273 municipalities with more than 100,000 inhabitants. The final sample comprised 24,923 adolescents. A self-administered questionnaire was used. Blood tests included glucose, insulin, glycosylated hemoglobin A and serum lipids. Age, sex, skin color, school type, body mass index (BMI), physical activity, and Brazilian regions were studied as possible effect modifiers and/or confounders using linear regression.

RESULTS

A significant positive association was found between more than 12 h of nocturnal sleep and glycosylated hemoglobin A in two Brazilian regions: Southeast and South, even after adjustment for age, sex, skin color, and BMI (coefficients of 0.142 and 0.339, respectively). No association was found with nocturnal sleep duration <7 h.

CONCLUSION

Notably, a significant positive relationship was found between more than 12 h of nocturnal sleep duration and glycosylated hemoglobin A in two Brazilian regions. The specific pubertal sleep curtailment can be a compensatory mechanism for dealing with the insulin resistance during adolescence. Those that escape from this regulatory strategy and sleep longer than the adequate duration, break down this balance and tend to damage their glucose metabolism. To our knowledge, this is the first large scale study, of the association between sleep duration and glucose metabolism in adolescents.

Aiding sleep in type 2 diabetes: therapeutic considerations

Insomnia and obstructive sleep apnoea (OSA) are more prevalent in patients with type 2 diabetes than in the general population. Both insomnia and OSA have been linked to cardiometabolic alterations (eg, hypertension, increased activity of the sympathetic nervous system, and systemic insulin resistance) that can exacerbate the pathophysiology of type 2 diabetes. Improvement of sleep in patients with diabetes could therefore aid the treatment of diabetes. To help health practitioners choose the best clinical tool to improve their patients' sleep without detrimentally affecting glucose regulation, this Review critically analyses the effects of common treatments for insomnia and OSA on both sleep and glucose metabolism in patients with type 2 diabetes. These treatments include pharmaceutical sleep aids (eg, benzodiazepine receptor agonists, melatonin) and cognitive behavioural therapy for insomnia, continuous positive airway pressure for OSA, and lifestyle interventions.

Relation of insulin resistance to neurocognitive function and electroencephalography in obese children

BACKGROUND

Childhood obesity may lead to neuronal impairment in both the peripheral and the central nervous system. This study aimed to investigate the impact of obesity and insulin resistance (IR) on the central nervous system and neurocognitive functions in children.

METHODS

Seventy-three obese children (38 male and 35 female) and 42 healthy children (21 male and 21 female) were recruited. Standard biochemical indices and IR were evaluated. The Wechsler Intelligence Scale for Children-Revised (WISC-R) and electroencephalography (EEG) were administered to all participants. The obese participants were divided into two groups based on the presence or absence of IR, and the data were compared between the subgroups.

RESULTS

Only verbal scores on the WISC-R in the IR+ group were significantly lower than those of the control and IR- groups. There were no differences between the groups with respect to other parameters of the WISC-R or the EEG. Verbal scores of the WISC-R were negatively correlated with obesity duration and homeostatic model assessment-insulin resistance (HOMA-IR) values. EEGs showed significantly more frequent 'slowing during hyperventilation' (SDHs) in obese children than non-obese children.

CONCLUSIONS

Neurocognitive functions, particularly verbal abilities, were impaired in obese children with IR. An early examination of cognitive functions may help identify and correct such abnormalities in obese children.

Inadequate sleep as a contributor to type 2 diabetes in children and adolescents

Lack of sleep is a modifiable risk factor for adverse health in humans. Short sleep duration and poor sleep quality are common in the pediatric population; the largest decline in sleep duration over the past decades has been seen in children and adolescents. The objective of the present narrative review was to provide for the first time an overview of the literature on sleep and its association with type 2 diabetes mellitus (T2D) biomarkers in children and adolescents. For this narrative review, 23 studies were retained (21 observational and 2 experimental studies). Notwithstanding the conflicting results found in these studies and despite being attenuated by adiposity level, maturity, sex and age, there is still some compelling evidence for an association between sleep duration (for both objective or subjective measurements of duration) and architecture with one or more T2D biomarkers in children and adolescents. The majority of the studies reviewed did focus on sleep duration and one or more T2D biomarkers in children and adolescents, but sleep architecture, more precisely the suppression of slow wave sleep and rapid eye movement sleep, has also been shown to be associated with insulin resistance. Only two studies looked at sleep quality, and the association between sleep quality and insulin resistance was not independent of level of adiposity. Future experimental studies will help to better understand the mechanisms linking insufficient sleep with T2D. Work also needs to be carried out on finding novel and effective strategies aimed at improving sleep hygiene and health outcomes of children and adolescents.

Is sleep education an effective tool for sleep improvement and minimizing metabolic disturbance and obesity in adolescents?

The prevalence of childhood obesity has increased significantly in recent years. Obesity is associated with a range of adverse physiological, psychological and social outcomes and places a huge economical burden on healthcare systems around the world. Insufficient sleep duration is common in adolescents and exacerbated by contemporary lifestyles, but may be a contributor to obesity onset and metabolic disruption. We briefly review the current evidence surrounding the associations between sleep and obesity as well as diabetes. Sleep improvement programs have been suggested as a potential avenue to raise awareness of the importance of sleep and ultimately enhance sleep behaviors/routines. A review of the current literature supporting the efficacy of such programs is tentative. Furthermore, very few studies have investigated if sleep enhancement has downstream positive effects on metabolic function or body weight in adolescents. We highlight biological and social factors that intensify sleep loss in adolescents and recommend that these be targeted components in future interventions aimed at improving adolescent sleep.

Effect of Slow Wave Sleep Disruption on Metabolic Parameters in Adolescents

STUDY OBJECTIVES

Cross-sectional studies report a correlation between slow wave sleep (SWS) duration and insulin sensitivity (SI) in children and adults. Suppression of SWS causes insulin resistance in adults but effects in children are unknown. This study was designed to determine the effect of SWS fragmentation on SI in children.

METHODS

Fourteen pubertal children (11.3-14.1 y, body mass index 29(th) to 97(th) percentile) were randomized to sleep studies and mixed meal (MM) tolerance tests with and without SWS disruption. Beta-cell responsiveness (Φ) and SI were determined using oral minimal modeling.

RESULTS

During the disruption night, auditory stimuli (68.1 ± 10.7/night; mean ± standard error) decreased SWS by 40.0 ± 8.0%. SWS fragmentation did not affect fasting glucose (non-disrupted 76.9 ± 2.3 versus disrupted 80.6 ± 2.1 mg/dL), insulin (9.2 ± 1.6 versus 10.4 ± 2.0 μIU/mL), or C-peptide (1.9 ± 0.2 versus 1.9 ± 0.1 ng/mL) levels and did not impair SI (12.9 ± 2.3 versus 10.1 ± 1.6 10(-4) dL/kg/min per μIU/mL) or Φ (73.4 ± 7.8 versus 74.4 ± 8.4 10(-9) min(-1)) to a MM challenge. Only the subjects in the most insulin-sensitive tertile demonstrated a consistent decrease in SI after SWS disruption.

CONCLUSION

Pubertal children across a range of body mass indices may be resistant to the adverse metabolic effects of acute SWS disruption. Only those subjects with high SI (i.e., having the greatest "metabolic reserve") demonstrated a consistent decrease in SI. These results suggest that adolescents may have a unique ability to adapt to metabolic stressors, such as acute SWS disruption, to maintain euglycemia. Additional studies are necessary to confirm that this resiliency is maintained in settings of chronic SWS disruption.

Effects of sleep disruption and high fat intake on glucose metabolism in mice

Poor sleep quality or quantity impairs glycemic control and increases risk of disease under chronic conditions. Recovery sleep may offset adverse metabolic outcomes of accumulated sleep debt, but the extent to which this occurs is unclear. We examined whether recovery sleep improves glucose metabolism in mice subjected to prolonged sleep disruption, and whether high fat intake during sleep disruption exacerbates glycemic control. Adult male C57BL/6J mice were subjected to 18-h sleep fragmentation daily for 9 days, followed by 1 day of recovery. During sleep disruption, one group of mice was fed a high-fat diet (HFD) while another group was fed standard laboratory chow. Insulin sensitivity and glucose tolerance were assessed by insulin and glucose tolerance testing at baseline, after 3 and 7 days of sleep disruption, and at the end of the protocol after 24h of undisturbed sleep opportunity (recovery). To characterize changes in sleep architecture that are associated with sleep debt and recovery, we quantified electroencephalogram (EEG) recordings during sleep fragmentation and recovery periods from an additional group of mice. We now report that 9 days of 18-h daily sleep fragmentation significantly reduces rapid eye movement sleep (REMS) and non-rapid eye movement sleep (NREMS). Mice respond with increases in REMS, but not NREMS, during the daily 6-h undisturbed sleep opportunity. However, both REMS and NREMS increase significantly during the 24-h recovery period. Although sleep disruption alone has no effect in this protocol, high fat feeding in combination with sleep disruption impairs glucose tolerance, effects that are reversed by recovery sleep. Insulin sensitivity modestly improves after 3 days of sleep fragmentation and after 24h of recovery, with significantly greater improvements in mice exposed to HFD during sleep disruption. Improvements in both glucose tolerance and insulin sensitivity are associated with NREMS rebound, raising the possibility that this sleep phase contributes to restorative effects of recovery sleep on glycemic control.

Association between poor glycemic control, impaired sleep quality, and increased arterial thickening in type 2 diabetic patients

Objective

Poor sleep quality is an independent predictor of cardiovascular events. However, little is known about the association between glycemic control and objective sleep architecture and its influence on arteriosclerosis in patients with type-2 diabetes mellitus (DM). The present study examined the association of objective sleep architecture with both glycemic control and arteriosclerosis in type-2 DM patients.

Design

Cross-sectional study in vascular laboratory.

Methods

The subjects were 63 type-2 DM inpatients (M/F, 32/31; age, 57.5±13.1) without taking any sleeping promoting drug and chronic kidney disease. We examined objective sleep architecture by single-channel electroencephalography and arteriosclerosis by carotid-artery intima-media thickness (CA-IMT).

Results

HbA1c was associated significantly in a negative manner with REM sleep latency (interval between sleep-onset and the first REM period) (β=-0.280, p=0.033), but not with other measurements of sleep quality. REM sleep latency associated significantly in a positive manner with log delta power (the marker of deep sleep) during that period (β=0.544, p=0.001). In the model including variables univariately correlated with CA-IMT (REM sleep latency, age, DM duration, systolic blood pressure, and HbA1c) as independent variables, REM sleep latency (β=-0.232, p=0.038), but not HbA1c were significantly associated with CA-IMT. When log delta power was included in place of REM sleep latency, log delta power (β=-0.257, p=0.023) emerged as a significant factor associated with CA-IMT.

Conclusions

In type-2 DM patients, poor glycemic control was independently associated with poor quality of sleep as represented by decrease of REM sleep latency which might be responsible for increased CA-IMT, a relevant marker for arterial wall thickening.

Association between sleep architecture and glucose tolerance in children and adolescents

BACKGROUND

Short sleep duration is a contributing factor for decreased insulin sensitivity and hyperglycemia. Sleep architecture represents a cyclical pattern of sleep that shifts between sleep Stages N1, N2, N3 (slow wave sleep) and Stage R (rapid eye movement sleep). The aim of the present study was to examine the association between sleep architecture and glucose and insulin metabolism in both normal weight and overweight/obese children and adolescents.

METHODS

A total of 118 subjects participated in the study. Subjects under-went overnight polysomnography (PSG) when the percentage of total sleep time (% TST) spent at each sleep stage was recorded and an oral glucose tolerance test together was performed the next morning. We assessed glucose tolerance, insulin sensitivity and pancreatic β-cell function using 2-h glucose levels, the Matsuda index (IS(OGTT)), and insulin secretion-sensitivity index-2 (ISSI-2), respectively.

RESULTS

After adjustment for age, gender, body mass index z-score, pubertal status, and obstructive apnea hypopnea index, Stage N3 (% TST) was positively associated with IS(OGTT), whereas Stage N1 (%TST) exerted an opposite effect on IS(OGTT). Higher sleep efficiency and longer TST were independently associated with lower 2-h glucose levels, higher ISSI-2 and/or higher IS(OGTT).

CONCLUSIONS

Stage N3, sleep efficiency and TST were protective factors in maintaining glucose and insulin homeostasis; however, Stage N1 functioned in the opposite direction.

Metabolic and glycemic sequelae of sleep disturbances in children and adults

The prevalence of obesity in adults and children has increased greatly in the past three decades, as have metabolic sequelae, such as insulin resistance and type 2 diabetes mellitus (T2DM). Sleep disturbances are increasingly recognized as contributors to this widespread epidemic in adults, and data are emerging in children as well. The categories of sleep disturbances that contribute to obesity and its glycemic co-morbidities include the following: (1) alterations of sleep duration, chronic sleep restriction and excessive sleep; (2) alterations in sleep architecture; (3) sleep fragmentation; (4) circadian rhythm disorders and disruption (i.e., shift work); and (5) obstructive sleep apnea. This article reviews current evidence supporting the contributions that these sleep disorders play in the development of obesity, insulin resistance, and T2DM as well as possibly influences on glycemic control in type 1 diabetes, with a special focus on data in pediatric populations.

An integrative review of sleep for nutrition professionals

Sleep is an essential lifestyle factor that contributes to overall health. The inverse relation between sleep duration and weight status has revealed the importance of sleep in nutritional health. This integrative review builds foundational knowledge with regard to sleep vis-à-vis nutrition by summarizing the importance and process of sleep, current sleep recommendations and trends, as well as lifestyle contributors to poor sleep. Additionally, it details the association between sleep and obesity and potential mechanisms for this association. Furthermore, guidance is offered regarding the incorporation of sleep considerations in nutrition counseling, communication, and research. Like many other lifestyle factors that contribute to nutritional health, sleep needs to be considered when examining weight management and health promotion.