Sleep and Lipid Profile During Transition from Childhood to Adolescence

Changes in sleep duration status and risk of high carotid intima-media thickness in children: A prospective cohort study

BACKGROUND

Short sleep duration is common in the pediatric population and is associated with an increased risk of high carotid intima-media thickness (cIMT), a marker of subclinical atherosclerosis. However, little is known regarding whether changes in sleep duration status over time can alter the risk of high cIMT in children.

OBJECTIVES

To examine the association between changes in sleep duration status and high cIMT in a cohort study of Chinese children.

METHODS

A total of 1115 children aged 6-11 years were enrolled in 2017 and then followed up in 2021 in the Huantai Childhood Cardiovascular Health Cohort Study. Children were categorized into four groups based on their sleep duration status (short vs. normal) at baseline and follow-up: persistent normal sleep duration, incident short sleep duration, resolved short sleep duration, and persistent short sleep duration. High cIMT was defined as cIMT levels ≥ age- and sex-specific 90th percentile values of this population.

RESULTS

Compared with children who maintained normal sleep duration, those with incident short sleep duration (odds ratio [OR]: 1.71, 95 % confidence interval [CI]: 1.05-2.77) or persistent short sleep duration (OR: 4.07, 95 % CI: 2.10-7.89) had a significantly increased risk of high cIMT at follow-up. Conversely, children who had short sleep duration at baseline but normal sleep duration at follow-up did not have an increased risk of high cIMT (OR: 1.08, 95 % CI: 0.47-2.49).

CONCLUSION

The development or persistence of short sleep duration is associated with an increased risk of high cIMT in children, whereas the resolution of short sleep duration may reduce such risk. These findings underscore the importance of preventing and managing short sleep duration to promote cardiovascular health in children.

Influence of sleep on physiological systems in atherosclerosis

Sleep is a fundamental requirement of life and is integral to health. Deviation from optimal sleep associates with numerous diseases including those of the cardiovascular system. Studies, spanning animal models to humans, show that insufficient, disrupted or inconsistent sleep contribute to poor cardiovascular health by disrupting body systems. Fundamental experiments have begun to uncover the molecular and cellular links between sleep and heart health while large-scale human studies have associated sleep with cardiovascular outcomes in diverse populations. Here, we review preclinical and clinical findings that demonstrate how sleep influences the autonomic nervous, metabolic and immune systems to affect atherosclerotic cardiovascular disease.

Is poor sleep quality associated with lipid profile in elderly population? Finding from Iranian Longitudinal Study on Ageing

BACKGROUND

Abnormal lipid profile as one of reversible cardiovascular disease risk factors might be affected by poor sleep quality.

AIM

This study aimed to assess the association between poor sleep quality and serum concentration of lipid profile in Iranian elderly population.

METHODS

The study was performed on a representative sample of 3452 Iranian older people (≥60 years) who contributed in the Iranian Longitudinal Study on Ageing (IRLSA). Sleep quality was measured through the validated Persian version of Pittsburgh Sleep Quality Index (PSQI). Fasting blood samples were collected from the participants to measure plasma levels lipid profile. We used multiple linear regression model to evaluate the independent association of poor sleep quality with lipid profile.

RESULTS

The mean age of participants was 68.0±6.7 years and 52.5% of them were male. In total, 52.4% of study population reported poor sleep quality (PSQI>5). Mean serum concentration of triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) was 143.2±74.2 mg/dl, 195.6±43.2 mg/dl, 112.9±31.0 mg/dl, and 57.3±12.4 mg/dl, respectively. Poor sleep quality was significantly associated with serum levels of TG (β=17.85; P=0.006), LDL-C (β=5.45; P=0.039) and HDL-C (β=-2.13; P=0.039) after adjusting for studied covariates.

CONCLUSION

Our study illustrates that poor sleep quality is a risk factor for poorer lipid profile. Therefore, early behavioral or pharmacological interventions that improve sleep quality are necessary to modify lipid profile in elderly population.

Catch-up sleep on free days and body mass index: results from the seventh Korea National Health and Nutrition Examination Survey, 2016

STUDY OBJECTIVES

We aimed to identify the relationship between duration of categorized catch-up sleep on free days (CUS) and measured body mass index (BMI) in adults using the data from the seventh Korean National Health and Nutrition Examination Survey (KNHANES VII), 2016.

METHODS

CUS duration was classified as ≤ 0, > 0-1, > 1-2, and > 2 hours. Being overweight or obese was defined as having a BMI ≥ 25.0 kg/m2 or ≥ 30.0 kg/m2, respectively.

RESULTS

Of 6,382 participants aged 19-80 years in the KNHANES VII survey of 2016, 201 and 583 participants were excluded because of shift-working and insufficient data, respectively. Of 5,598 participants, CUS was observed in 2,274 (44.9%) participants, of which 3,324 (55.1%), 1,043 (19.4%), 724 (14.7%), and 507 (10.8%) had CUS of ≤ 0, > 0-1, > 1-2, and > 2 hours, respectively; the prevalence of obesity was 5.6%, 5.6%, 4.8%, and 6.1%, respectively. The association between BMI and CUS duration showed a significant negative association in the CUS ≤ 0 hours group (beta [95% confidence interval], -0.394 [-0.646, -0.143], P = .002); however, other CUS groups did not show any significant association with BMI (CUS > 0-1 hours: -0.196 [-1.258, 0.865], P = .716; CUS > 1-2 hours, -0.542 [-1.625, 0.541], P = .325; CUS > 2 hours, -0.113 [-0.459, 0.233], P = .519).

CONCLUSIONS

Our findings provide an understanding of the relationship between CUS and BMI and can serve as an instructive basis for the management of BMI.

CITATION

Lee HJ, Cho S, Lee SH, Kim SJ, Kim KM, Chu MK. Catch-up sleep on free days and body mass index: results from the seventh Korea National Health and Nutrition Examination Survey, 2016. J Clin Sleep Med. 2024;20(1):39-47.

Genetic study of the causal effect of lipid profiles on insomnia risk: a Mendelian randomization trial

OBJECTIVES

In response to the controversy surrounding observational studies of the association between lipid profiles and the risk of insomnia, the aim of this study was to analyze lipid profiles, including triglycerides (TG), apolipoprotein A-1 (ApoA-1), apolipoprotein B (ApoB) and lipoprotein A (LPA), in a European population to further assess the causal relationship between these lipid types and insomnia.

MATERIALS AND METHODS

This study explores the causal effect of lipid profiles on insomnia based on a genome-wide association study (GWAS)-derived public dataset using two-sample and multivariate Mendelian randomization (MVMR) analysis. The main MR analyses used inverse variance weighting (IVW) odds ratio (OR), and the sensitivity analyses included weighted median (WM) and MR‒Egger.

RESULTS

Both MR and MVMR showed that lowering ApoA-1 and LPA levels had causal effects on the risk of insomnia [MR: per 10 units, ApoA-1: OR: 0.7546, 95% CI: 0.6075-0.9372, P = 0.011; LPA: OR: 0.8392, 95% CI: 0.7202-0.9778, P = 0.025; MVMR: per 10 units, ApoA-1: OR: 0.7600, 95% CI: 0.6362-0.9079, P = 0.002; LPA, OR: 0.903, 95% CI: 0.8283-0.9845, P = 0.021]. There were no causal effects of TG or ApoB on insomnia (all P > 0.05). The MR‒Egger intercept test, funnel plot, and IVW methods all suggested an absence of strong directional pleiotropy, and leave-one-out permutation analysis did not detect any single single-nucleotide polymorphism that had a strong influence on the results.

CONCLUSION

Elevated levels of ApoA-1 and LPA were independently and causally associated with the risk of insomnia, suggesting that elevated ApoA-1 and LPA levels may contribute to a reduced risk of insomnia.

An mHealth-Supported antenatal lifestyle intervention may be associated with improved maternal sleep in pregnancy: Secondary analysis from the PEARS trial

OBJECTIVE

To investigate the effect of an antenatal diet and exercise intervention during pregnancy on sleep duration. As a secondary objective, associations between sleep duration and gestational weight gain (GWG), maternal metabolic parameters and pregnancy outcomes were assessed.

DESIGN

Secondary analysis.

SETTING

Large tertiary Maternity Hospital in Dublin, Ireland.

POPULATION

326 women with overweight or obesity who participated in the Pregnancy Exercise And Nutrition Research Study (PEARS) randomised controlled trial between March 2013 and August 2016.

METHODS

Secondary analysis of a randomised trial.

MAIN OUTCOME MEASURES

Impact of the PEARS intervention on sleep duration, and association of sleep duration and maternal metabolic parameters, and pregnancy outcomes.

RESULTS

Participants had a mean age of 32.5 ± 4.5 years and median (interquartile range [IQR]) body mass index of 28.3 (26.6-31.2) kg/m² . The intervention group had a longer sleep duration in late pregnancy (mean difference 17.1 minutes (95% confidence interval [CI] 0.5-33.7) and a higher proportion achieving optimum sleep duration of 7-9 h (54.3 vs. 42.9%, relative risk [RR] 1.28 (95% CI 1.01-1.62). In late pregnancy, sleep duration of <6 h was associated with lower breastfeeding rates on discharge (RR 0.74, 95% CI 0.57-0.95) and higher triglyceride levels (mean difference 0.24, 95% CI 0.10-0.38). There were no significant associations between sleep and incidence of gestational diabetes mellitus or pre-eclampsia/toxaemia, or other metabolic parameters assessed (insulin, fasting glucose, HOMA-IR).

CONCLUSION

A diet and exercise intervention from early pregnancy may promote longer and optimal sleep duration, with maternal benefits such as lower triglyceride levels and higher breastfeeding rates.

Effect of sleep disturbance on biomarkers related to the development of adverse health outcomes: A systematic review of the human literature

Literature suggests that unrestricted and undisturbed sleep is vital for basic human function and performance; however, it is unclear as to what amount of sleep disturbance leads to dysregulation in biomarkers, which may underscore the development of adverse health effects. This systematic review aims to identify the amount of sleep disturbance that contributes to biomarker changes as a potential precursor to the development of adverse health effects. English-language comparative studies available in PubMed, Cochrane Central, EMBASE, and CINAHL databases from 1 January 1980 to 31 July 2021 were searched. Where possible, random-effects meta-analyses were used to examine the effect of sleep disturbances on adverse health effects. The risk of bias of individual studies was assessed using the Cochrane Risk of Bias Tool and the Risk of Bias of Nonrandomised Studies - of Exposures instruments and the certainty of the body of evidence for each outcome was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. The search identified 92 primary studies reporting on blood pressure, hypertension, heart rate, cardiac arrhythmia, cardiac output, waist circumference, cortisol, adrenaline, noradrenaline, immune system markers, glucose, insulin, cholesterol, and triglyceride levels. Although some meta-analyses suggested there may be an association between sleep disturbances and certain outcomes, the certainty in the evidence was very low due to concerns with risk of bias, inconsistency across exposures, populations, and imprecision in the estimates of effects. Further research is needed to explore the point at which types, levels and duration of sleep disturbances may begin to increase the risk of developing adverse health outcomes to inform and tailor health interventions.

Sleep duration and risk of hyperlipidemia: a systematic review and meta-analysis of prospective studies

PURPOSE

Current studies indicate that the association between sleep duration and risk of hyperlipidemia is uncertain. This systematic review aimed to evaluate relevant prospective studies and make a definite conclusion.

METHODS

Three databases were searched for prospective studies on the relationship between sleep duration and hyperlipidemia risk from their inception to October 2020.

RESULTS

We identified twelve studies involving 114,439 participants. Follow-up for incident hyperlipidemia ranged from 200 days to 10 years. Neither long (RR:1.00, 95%CI:0.90-1.11, P > 0.05) nor short (RR:0.99, 95%CI:0.94-1.05, P > 0.05) sleep duration had a significant association with increased hyperlipidemia risk in adults. However, long sleep duration was decidedly associated with low HDL-C (RR:0.19, 95%CI: - 0.03-0.40, P < 0.05) and high triglycerides (RR: - 0.20, 95%CI: - 0.43-0.03, P < 0.05) in children and adolescents.

CONCLUSION

Long sleep duration has strong associations with risks of low HDL-C and high triglycerides in children and adolescents. The mechanisms underlying this association deserves to be explored in future studies.

Gestational sleep deprivation is associated with higher offspring body mass index and blood pressure

Study Objectives

The objective of this study was to evaluate the association between gestational sleep deprivation and childhood adiposity and cardiometabolic profile.

Methods

Data were used from two population-based birth cohorts (Rhea study and Amsterdam Born Children and their Development study). A total of 3,608 pregnant women and their children were followed up until the age of 11 years. Gestational sleep deprivation was defined as 6 or fewer hours of sleep per day, reported by questionnaire. The primary outcomes included repeated measures of body mass index (BMI), waist circumference, body fat, serum lipids, systolic and diastolic blood pressure (DBP) levels in childhood. We performed a pooled analysis with adjusted linear mixed effect and Cox proportional hazards models. We tested for mediation by birthweight, gestational age, and gestational diabetes.

Results

Gestational sleep deprivation was associated with higher BMI (beta; 95% CI: 0.7; 0.4, 1.0 kg/m²) and waist circumference (beta; 95% CI: 0.9; 0.1, 1.6 cm) in childhood, and increased risk for overweight or obesity (HR; 95% CI: 1.4; 1.1, 2.0). Gestational sleep deprivation was also associated with higher offspring DBP (beta; 95% CI: 1.6; 0.5, 2.7 mmHg). The observed associations were modified by sex (all p-values for interaction < 0.05); and were more pronounced in girls. Gestational diabetes and shorter gestational age partly mediated the seen associations.

Conclusions

This is the first study showing that gestational sleep deprivation may increase offspring’s adiposity and blood pressure, while exploring possible mechanisms. Attention to glucose metabolism and preterm birth might be extra warranted in mothers with gestational sleep deprivation.

Association between Berlin Questionnaire Index and lipid profile

Objective:

This study aimed to evaluate the association between the Berlin questionnaire index and the lipid profile, according to gender.

Method:

This is a cross-sectional study. The group investigated was composed of the Bahiana School of Medicine and Public Health (EBMSP) employees by a sequential non-probabilistic sampling. Study design: The data were obtained by applying a validated questionnaire and collecting laboratory blood samples at the Outpatient Clinics of EBMSP.

Results:

The total sample consisted of 94 employees, 21 of whom were excluded because they had not been submitted to blood collection. The sample profile evaluation had a total of 73 employees and obtained the following results in the study: the female was the most prevalent with (54.8%); the age ranged from 18 to 65 years, with a mean 38 ± 10.6 years; in men with positive Berlin (with respiratory sleep disorder), higher values of total cholesterol and LDL-c, and lower HDL-c were observed when compared to men without respiratory sleep disorder, as follows: total cholesterol (202 ± 19 vs. 180±40; p=0.040); LDL-c (137± 17 vs. 113 ± 34; p=0.048); lower HDL-c (37 ± 6 vs. 42,5 ±8; p=0.047). While in women, no significant change was observed among those with positive Berlin when compared with those with negative Berlin.

Conclusion:

The findings of this study showed that men with positive Berlin (with a respiratory sleep disorder) had higher values of total cholesterol, LDL-c, and lower HDL-c when compared to men without a respiratory sleep disorder.

Sleep disturbance and the long-term impact of early adversity

Sleep disturbance may be a central, yet underappreciated mechanism by which early adversity has a long-term impact upon mental and physical health. The fundamental regulatory processes shaped by early adversity - neural, neuroendocrine, and immune - are also central to sleep. Sleep problems, in turn, lead to a similar constellation of chronic health problems that have been linked to early adversity. We bring together work from the fields of early adversity and sleep in order to suggest a model by which sleep disturbance plays a critical role in the far-reaching impacts of early adversity on health. Future research should employ more longitudinal designs and pay particular attention to the impact of developmental periods such as adolescence and midlife when maturational and environmental factors conspire to create a unique time of sleep disturbance. We also suggesting that intervening to minimize sleep disturbance may be a promising means by which to test the model, as well as potentially blunt the long-term impact of early adversity on health.

Role of nutritional status and physical activity in the relationship between sleep quality and cardiometabolic profile of children

OBJECTIVE

To verify if there is an association between sleep quality and cardiometabolic risk factors (CMRF) score of children and the role of nutritional status and physical activity (PA) levels in this relationship.

MATERIAL AND METHODS

Cross- sectional study, with 83 schoolchildren, aged 6 and 11 years, from Porto Alegre, Brazil. PA was assessed with accelerometer and nutritional status through body mass index. Total cholesterol, triglycerides, glucose, and insulin were collected to calculate CMRF score. Parents' perception of their children's sleep was evaluated through a question. Generalized linear models were used.

RESULTS

Poor sleep quality was positively associated with CMRF (ß=0.48; CI 95%=0.23;0.73) in relation to those with good sleep quality. A positive association was found in overweight children with poor sleep quality (ß=0.52; CI 95%=0.17;0.86), as well as in inactive children with poor sleep quality (ß=0.58; CI 95%=0.14;1.02) with CMRF.

CONCLUSION

Poor sleep quality integrated with overweight and physical inactivity influences on CMRF of children.

Influence of organised sports practice during adolescence on health of adult women with special emphasis on participation in aesthetic sports

This study aimed to assess the differences in psychosocial health and cardiometabolic risk during adulthood in women based on previously organised sport (OS) participation during adolescence and current activity levels, with emphasis on participation in aesthetic sports. The study included 1947 women aged 18-55 years who were categorised into four groups: 355 aesthetic athletes during adolescence, 494 non- aesthetic athletes during adolescence, 791 non-athletes during adolescence with similar current levels of physical activity (PA) to OS groups and 307 currently inactive non-athletes during adolescence. Participants answered questionnaires regarding sport participation, psychosocial health and cardiometabolic risk. The results show that non-athletes during adolescence who are currently inactive reported significantly lower psychosocial health and higher cardiometabolic risk scores. Women with currently homogenous PA levels (χ² = 0.514) reported similar physical quality of life (QoL), exercise addiction, anxiety and depression symptoms regardless of participation in OS during adolescence (P > .05), except aesthetic athletes who reported the worst sleep and mental QoL. Very high training volumes in aesthetic athletes did not influence psychological outcomes and cardiometabolic risk in adulthood compared to lower training volumes. In conclusion, the effects of PA during adulthood appear to be powerful enough to induce beneficial adaptations in health outcomes that match those observed in women who participate in OS during adolescence, except for aesthetic sports participants, who show a high risk of lower quality of sleep in adulthood. PA should be promoted in adults and especially women who have not participated in OS during adolescence.

Association between weekend catch-up sleep and high-sensitivity C-reactive protein levels in adults: a population-based study

STUDY OBJECTIVES

To investigate the association between weekend catch-up sleep (WCS) and the levels of high-sensitivity C-reactive protein (hsCRP)-a serum inflammatory maker-in adults.

METHODS

Data of 5,506 adults aged 19 years or older were obtained from the nationwide cross-sectional Korea National Health and Nutrition Examination Surveys conducted in 2016. Serum hsCRP level, weekday and weekend sleep durations, and sociodemographic and health-related characteristics were assessed. Participants whose weekend sleep duration was more than 1 h longer than their weekday sleep duration were included in the WCS group. hsCRP level was categorized into quartiles (i.e. highest, middle-high, middle-low, and lowest). Obesity was defined by body mass index ≥ 25.0 kg/m2.

RESULTS

The WCS group included 1,901 participants (34.5%). In the logistic regression analysis controlling for all variables, adults in the WCS group were significantly less likely to show the highest hsCRP level (versus the lowest level) compared with those without WCS in the complete sample (adjusted odds ratio = 0.795, 95% confidence interval [CI] = 0.662 to 0.955). In a subgroup analysis, this association was significant only for those with weekday sleep duration of 6 h or lower. Longer WCS (≥3 h) was not associated with hsCRP levels. Non-obese people with WCS demonstrated a lower risk for high hsCRP levels, while there was no significant difference in obese people with WCS.

CONCLUSIONS

Our findings indicate that WCS may be beneficial for low-grade systemic inflammation in adults, particularly among those with shorter weekday sleep durations. WCS may also interact with obesity.

Polygenic impact of morningness on the overnight dynamics of sleep spindle amplitude

Sleep spindles are thalamocortical oscillations that contribute to sleep maintenance and sleep-related brain plasticity. The current study is an explorative study of the circadian dynamics of sleep spindles in relation to a polygenic score (PGS) for circadian preference towards morningness. The participants represent the 17-year follow-up of a birth cohort having both genome-wide data and an ambulatory sleep electroencephalography measurement available ( N = 154, Mean age = 16.9, SD = 0.1 years, 57% girls). Based on a recent genome-wide association study, we calculated a PGS for circadian preference towards morningness across the whole genome, including 354 single-nucleotide polymorphisms. Stage 2 slow (9-12.5 Hz, N = 186 739) and fast (12.5-16 Hz, N = 135 504) sleep spindles were detected using an automated algorithm with individual time tags and amplitudes for each spindle. There was a significant interaction of PGS for morningness and timing of sleep spindles across the night. These growth curve models showed a curvilinear trajectory of spindle amplitudes: those with a higher PGS for morningness showed higher slow spindle amplitudes in frontal derivations, and a faster dissipation of spindle amplitude in central derivations. Overall, the findings provide new evidence on how individual sleep spindle trajectories are influenced by genetic factors associated with circadian type. The finding may lead to new hypotheses on the associations previously observed between circadian types, psychiatric problems and spindle activity.

Effect of maternal sleep in late pregnancy on leptin and lipid levels in umbilical cord blood

OBJECTIVES

To study the impact of maternal sleep in late pregnancy on birth weight (BW) and leptin and lipid levels in umbilical cord blood.

STUDY DESIGN

A total of 277 healthy and singleton pregnancy women were recruited for participation in the Shanghai Sleep Birth Cohort Study (SSBC) during their 36-38 weeks of pregnancy, from May 2012 to July 2013. Maternal night sleep time (NST), sleep efficiency (SE), sleep onset latency (SOL) and the percentage of wake after sleep onset (WASO) in NST and midpoint of sleep (MSF) were measured by actigraphy for seven consecutive days. The leptin and lipid levels were determined in cord blood samples collected from the umbilical vein immediately after delivery. Birth information (birth weight, gender, delivery type, etc.) was extracted from medical records. A multivariable linear regression model was applied to examine the effect of maternal sleep in late pregnancy on newborn leptin and lipid levels in umbilical cord blood.

RESULTS

A total of 177 women and their infants were included in the analysis. Maternal mean NST was 7.03 ± 1.10 h in late pregnancy, and 48% had a shorter sleep time (NST < 7 h). The average maternal SE was 72.54% ± 9.66%. The mean percentage WASO/NST was 21.62% ± 9.98%; the average MSF was about 3:34 (0:53); and the SOL was 46.78 ± 36.00 min. After adjustment for confounders, both maternal NST and SE were found to be significantly associated with triglyceride levels (β = -0.219, p = 0.006; β = -0.224, p = 0.006) in umbilical cord blood; and maternal NST was also observed to have positive association with newborn leptin levels (β = 0.146, p = 0.047). However, we did not find significant association between other maternal sleep parameters in late pregnancy and leptin and lipid levels and birth weight.

CONCLUSIONS

Short sleep duration and poor sleep quality during late pregnancy were associated with newborn leptin and lipid levels, and efforts on improving maternal sleep during late pregnancy should be advocated for children's health.

Association between sleep duration, sleep quality and hyperlipidemia in middle-aged and older Chinese: The Dongfeng–Tongji Cohort Study

Aims

This study aimed to evaluate the relationship between sleep duration, sleep quality and hyperlipidemia in middle-aged and older Chinese.

Methods

We included 20,712 individuals at baseline from September 2008 to June 2010, and they were followed-up until October 2013. Hyperlipidemia was defined according to the Chinese guidelines on the prevention and treatment of dyslipidemia in adults. Sleep duration was self-reported and sleep quality was evaluated with a questionnaire that was designed according to the Pittsburgh Sleep Quality Index. Logistic regression and Cox proportional hazard models were conducted to explore the associations.

Results

In the cross-sectional analyses, longer sleep duration (≥10 h) was significantly associated with higher prevalence of hyperlipidemia (odds ratio (OR) = 1.17, 95% confidence interval (CI) = 1.02–1.35) after adjusting for potential confounders. The ORs of hyperlipidemia were significantly elevated among participants with impaired sleep quality (OR = 1.14, 95% CI = 1.08–1.22) and poor sleep quality (OR = 1.20, 95% CI = 1.08–1.34) when compared to those with good sleep quality. In the longitudinal analyses, compared to participants with a sleep duration of 7–<8 h, those with a sleep duration of 9–<10 h (hazard ratio (HR) = 1.19, 95% CI = 1.04–1.35) and ≥10 h (HR = 1.27, 95% CI = 1.02–1.58) showed significantly higher risk of hyperlipidemia after adjusting for potential confounders. However, no statistically significant association was found between impaired or poor sleep quality and hyperlipidemia.

Conclusions

Longer sleep duration was significantly associated with higher risk of hyperlipidemia. Impaired or poor sleep quality were associated with elevated prevalence of hyperlipidemia, but not with the incidence of hyperlipidemia.

Autistic Traits Are Associated With Decreased Activity of Fast Sleep Spindles During Adolescence

STUDY OBJECTIVES

Autistic traits present a continuum from mild symptoms to severe disorder and have been associated with a high prevalence of sleep problems. Sleep spindles have a key function in sleep maintenance and in brain plasticity. Previous studies have found decreased spindle activity in clinical autism. Here we examine the associations between the entire range of autistic traits and sleep spindle activity in a nonclinical community cohort of adolescents.

METHODS

Our cohort is based on 172 adolescents born in 1998 (58.7% girls, mean age = 16.9 years, standard deviation = 0.1), who filled in the adult autism-spectrum quotient (AQ), consisting of total score, and social interaction and attention to details subscales. Participants underwent an ambulatory overnight sleep electroencephalography. Sleep spindles (amplitude, duration, density, and intensity) were automatically detected from stage N2 sleep, and divided to slow and fast spindles.

RESULTS

Higher AQ total sum and social interaction sum associated with lower fast spindle amplitude and intensity (P < .04). No associations were observed for attention to details.

CONCLUSIONS

Our findings indicate that a higher level of autistic traits in the nonclinical range among generally healthy adolescents associate with similar alterations in sleep spindle activity as observed in many neuropsychiatric conditions, indicating lower sleep-related brain plasticity. This indicates that sleep microstructures form a continuum that follows self-reported symptoms of autism.

Role of sleep duration and sleep-related problems in the metabolic syndrome among children and adolescents

BACKGROUND

There is increasing recognition that sleep is a risk factor for metabolic syndrome (MetS). The aim of the present study was to analyze the relationship between self-reported sleep duration, sleep-related problems and the presence of MetS in children and adolescents from Bogotá, D.C., Colombia.

METHODS

This is a cross-sectional analysis from the FUPRECOL study (2014-15). Participants included 2779 (54.2% girls) youth from Bogota (Colombia). MetS was defined as the presence of ≥3 of the metabolic abnormalities (hyperglycemia, hypertriglyceridemia, low high-density lipoprotein cholesterol [HDL-c], hypertension, and increased waist circumference) according to the criteria of de Ferranti/Magge and colleges. Self-reported sleep duration and sleep-related problems were assessed with the BEARS questionnaire.

RESULTS

Logistic regression analysis showed that boys who meet recommended duration of sleep had a decreased risk of elevated blood glucose levels (Odds Ratio [OR] = 0.71, 95%CI [0.40-0.94]; p = 0.031) compared to boys who have short-long sleep duration. Also, compared to young without sleep problems, excessive sleepiness during the day was related to low HDL-c levels in boys (OR = 1.36, 95%CI [1.02-1.83]; p = 0.036) and high triglyceride levels in girls (OR = 1.28, 95%CI [1.01-1.63]; p = 0.045). Girls with irregular sleep patterns had decreased HDL-c levels (OR = 0.71, 95%CI [0.55-0.91]; p = 0.009).

CONCLUSIONS

Recommended sleep duration was associated with a decreased risk of elevated fasting glucose levels in boys, and sleep problems was related to lower HDL-c in girls and higher triglyceride levels in boys. These findings suggested the clinical importance of improving sleep hygiene to reduce metabolic risk factors in children and adolescents.

Association of sleep duration and quality with blood lipids: a systematic review and meta-analysis of prospective studies

OBJECTIVES

To assess the longitudinal evidence of the relationships between sleep disturbances (of quantity and quality) and dyslipidaemia in the general population and to quantify such relationships.

SETTING

Systematic review and meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

METHODS

We performed a systematic search of PubMed and Embase (up to 9 September 2017), complemented with manual searches, of prospective population studies describing the association between sleep duration and quality and the incidence of dyslipidaemias. Relative risks (95% CIs) were extracted and pooled using a random effects model. Subgroup analyses by lipid type were performed. Heterogeneity and publication bias were also assessed. Quality was assessed with Downs and Black score.

PARTICIPANTS

Studies were included if they were prospective, had measured sleep quantity and/or quality at baseline and either incident cases of dyslipidaemia or changes in blood lipid fractions assessed prospectively.

PRIMARY OUTCOME MEASURES

Incidence of dyslipidaemia and changes in lipid fractions. Dyslipidaemia was defined as a high total cholesterol, triglycerides, low-density lipoprotein cholesterol or low high-density lipoprotein cholesterol compared with the reference group.

RESULTS

Thirteen studies were identified (eight using sleep duration, four sleep quality and one both). There was heterogeneity in the sleep quality aspects and types of lipids assessed. Classification of sleep duration (per hour/groups) also varied widely. In the pooled analysis of sleep duration (6 studies, 16 cohort samples; 30 033 participants; follow-up 2.6-10 years), short sleep was associated with a risk of 1.01 (95% CI 0.93 to 1.10) of developing dyslipidaemia, with moderate heterogeneity (I2=56%, P=0.003) and publication bias (P=0.035). Long sleep was associated with a risk of 0.98 (95% CI 0.87 to 1.10) for dyslipidaemia, with heterogeneity (I2=63%, P<0.001) and no significant publication bias (P=0.248).

CONCLUSION

The present analysis was unable to find supportive evidence of a significant relationship between sleep duration and the development of dyslipidaemia. However, heterogeneity and small number of studies limit the interpretation.

PROSPERO REGISTRATION NUMBER

CRD42016045242.

Circadian preference towards morningness is associated with lower slow sleep spindle amplitude and intensity in adolescents

Individual circadian preference types and sleep EEG patterns related to spindle characteristics, have both been associated with similar cognitive and mental health phenotypes. However, no previous study has examined whether sleep spindles would differ by circadian preference. Here, we explore if spindle amplitude, density, duration or intensity differ by circadian preference and whether these associations are moderated by spindle location, frequency, and time distribution across the night. The participants (N = 170, 59% girls; mean age = 16.9, SD = 0.1 years) filled in the shortened 6-item Horne-Östberg Morningness-Eveningness Questionnaire. We performed an overnight sleep EEG at the homes of the participants. In linear mixed model analyses, we found statistically significant lower spindle amplitude and intensity in the morning as compared to intermediate (P < 0.001) and evening preference groups (P < 0.01; P > 0.06 for spindle duration and density). Spindle frequency moderated the associations (P < 0.003 for slow (<13 Hz); P > 0.2 for fast (>13 Hz)). Growth curve analyses revealed a distinct time distribution of spindles across the night by the circadian preference: both spindle amplitude and intensity decreased more towards morning in the morning preference group than in other groups. Our results indicate that circadian preference is not only affecting the sleep timing, but also associates with sleep microstructure regarding sleep spindle phenotypes.