Is there an association between adolescent sleep restriction and obesity

The Longitudinal Interplay between Sleep, Anthropometric Indices, Eating Behaviors, and Nutritional Aspects: A Systematic Review and Meta-Analysis

Sleep is fundamental for adolescents' healthy development but undergoes dramatic changes in quantity and quality due to the conflict between biological and social rhythms. Insufficient sleep has been associated with worse physical health status and irregular eating behaviors in adolescents. This review aims to systematically synthesize the longitudinal associations between adolescents' sleep dimensions (i.e., duration, timing, quality, and insomnia symptoms) and physical health indicators (i.e., anthropometric indices, fat percentage, and risk of obesity), eating behaviors, and nutritional aspects (i.e., type of diet related to the intake of specific foods and nutrients, amount and timing of food consumption, energy expenditure). A total of 28 longitudinal studies were included. The meta-analytic results showed that longer sleep duration, better sleep quality, and lower insomnia symptoms were associated with lower BMI and fat percentage and that shorter sleep duration (<7 h) and lower sleep quality were associated with a higher risk of obesity. Conversely, anthropometric indices were not related to sleep over time. Limited literature examined the bidirectional association between adolescents' sleep and their eating behaviors and nutritional aspects. Such knowledge sheds new light on the role of sleep for adolescents' health, highlighting the need to examine further the interplay between these variables.

Weekday time in bed and obesity risk in adolescence

INTRODUCTION

Sleep curtailment is associated with obesity in children, but few studies have investigated this relationship in a longitudinal sample of adolescents. The aim of the present study was to examine the longitudinal association between weekday time in bed (TIB) at age 10-13 and overweight at age 16-19.

METHODS

Adolescents and their parents (N = 3025 families), participating in a longitudinal population-based study, completed questionnaires assessing habitual bedtime and wake time on weekdays, weight and height, socioeconomic status (SES), internalizing mental health problems and disturbed eating. Two surveys were administered with a 6-year interval (T1 and T2). A one-way analysis of covariance (ANCOVA) was performed examining the association between TIB and weight category 6 years later, with SES, internalizing problems and disturbed eating at baseline entered as covariates. Hierarchical and logistic regression analyses were used to assess TIB at age 10-13 years to as a predictor of body mass index (BMI) standardized deviation scores (SDS) and overweight status at age 16-19 adjusting for the same confounders and baseline BMI.

RESULTS

A linear inverse relationship between TIB at age 10-13 and BMI category at age 16-19 was demonstrated by the ANCOVA, p < 0.001. Shorter TIB was related to higher weight, but the effect size was small (partial eta squared = 0.01). When adjusting for the included baseline confounders in the hierarchical regression model TIB significantly predicted later BMI SDS (β = -0.039, p = 0.02). The adjusted logistic regression model showed that for each hour reduction of TIB at T1 the odds of being overweight/obese at T2 increased with a factor of 1.6.

CONCLUSION

Shorter TIB was found to be a significant, yet modest, independent predictor of later weight gain in adolescence. The findings implicate that establishing healthy sleep habits should be addressed in prevention and treatment strategies for adolescent obesity.

Sleep duration and obesity in children and adolescents: evidence from an updated and dose-response meta-analysis

BACKGROUND AND OBJECTIVES

The association between sleep duration and obesity in children and adolescents has been widely evaluated, whereas the current findings are mixed and prospective studies are limited. To shed more light on this issue and explore the dose-response relationship, we performed the present updated meta-analysis by synthesizing the results of prospective cohorts.

METHODS

Literature retrieval, study selection and data extraction were completed independently and in duplicate. Effect-size estimates are expressed as relative risk (RR) with 95% confidence interval (CI) or standardized regression coefficient (β) with standard error.

RESULTS

Data from 33 articles, involving 57,848 children and adolescents, were meta-analyzed. Overall analyses revealed statistically significant associations of short (adjusted RR = 1.57, 95% CI: 1.36 to 1.81, P < 0.001) and long sleep duration (0.83, 0.75 to 0.93, 0.001) with obesity. Short sleep duration was also associated with significant changes in body mass index z-score (mean difference = -0.06; 95% CI: -0.09 to -0.04; P < 0.001). By contrast, long sleep duration was identified as a protective factor for childhood obesity. In dose-response analyses, short sleep duration was significantly associated with obesity in toddlers (1-2 years) (adjusted RR = 1.20, 95% CI: 1.07 to 1.34, P = 0.001), preschool-aged (3-5 years) children (1.58, 1.36 to 1.83, <0.001), and school-aged (6-13 years) children (1.82, 1.51 to 2.21, <0.001). In subgroup analyses, geographic region, sleep duration assessment, age, and follow-up interval were possible sources of heterogeneity.

CONCLUSIONS

Our findings indicate that short sleep duration can increase the risk of obesity in children and adolescents, especially within 3-13 years of age, and long sleep duration seemed beneficial in preventing obesity.

Sleep Extension Increases the Effect of Caloric Restriction Over Body Weight and Improves the Chronic Low-Grade Inflammation in Adolescents With Obesity

PURPOSE

Diminution of sleep may be associated with obesity. However, evidence that extending sleep duration might favor weight loss is insufficient. The aim of this study was to compare the effect of dietary restriction with or without prescription of sleep extension on weight loss in adolescents with obesity.

METHODS

A total of 52 adolescents with obesity (24 males and 28 females) received a diet with 500 calories restriction, randomly allocated to groups without (n = 27) and with sleep extension (n = 25) for 4 weeks. We collected data on anthropometry, caloric intake, and self-reported sleep diaries. Serum interleukin 6, tumor necrosis factor α, leptin, and insulin levels were quantified by enzyme-linked immunosorbent assay. Cortisol and 6-sulfatoxymelatonin excretions were measured in the first urine collection in the morning by liquid chromatography-mass spectrometry. Measurements were carried out at baseline and at the end of the intervention.

RESULTS

After diet, weight decreased in both groups. Sleep extension, improved weight loss (p < .00001), and waist girth reduction (p = .00003), with diminution of insulin (p = .002) and interleukin 6 levels (p = .02). Caloric restriction was less effective in adolescent females. No differences in cortisol or 6-sulfatoxymelatonin excretion were found.

CONCLUSIONS

A sleep extension favors weight loss in adolescents under caloric restriction and improves inflammation and metabolic conditions, thus supporting a possible additional benefit to diet in the treatment of obesity in adolescents.

Psychophysiological insomnia and respiratory tract infections: results of an infection-diary-based cohort study

STUDY OBJECTIVES

The immune theory of sleep suggests an important role of sleep for a functioning immune system. Insomnia has been associated with heightened risk for infections. The aim of the study was to test whether psychophysiological insomnia (PI) is associated with subsequent respiratory tract infections (RTIs) in the context of an infection-diary-based cohort study.

METHODS

We recruited 674 adults from a cross-sectional survey on airway infections into the airway infection susceptibility (AWIS) cohort and invited them to self-report in diaries incident RTIs experienced during 7097 months (mean of 11.9 months of completed infection diaries per individual). The Regensburg Insomnia Scale (RIS) was assessed at baseline to measure PI. As outcome, we considered an infection diary score summing up prospectively reported RTIs.

RESULTS

The RIS score correlated significantly with the infection diary score summarizing reported RTIs (correlation coefficient = 0.265, p < 0.001). Adjustments by putative confounders did only marginally affect this relationship. No significant differences in the relationship between RIS score and diary score were found for subgroups including those by gender, body mass index, perceived stress, and comorbidity. People affected by a combination of high PI and obesity were eight times more likely to belong to the group reporting the highest 10% of RTIs compared to the nonobese group with low RIS score (p < 0.001). A high RIS score in men was associated with a higher neutrophil-to-lymphocyte ratio, an indicator of inflammation.

CONCLUSIONS

Our data support the relevance of adequate sleep for an immune system ready to fight pathogens and prevent airway infections.

[Factors associated with sleep disorders in university students]

The objective was to investigate sleep disorders and associated sociodemographic and behavioral factors. A census of university students was carried out. Questions extracted from the Munich Chronotype Questionnaire investigated: insufficient sleep duration (< 6 hours/day for < 65 years and < 5 hours/day for other ages), long latency (> 30 minutes), low self-rated sleep quality, nocturnal awakenings (involuntary, in the middle of the night), and daytime sleepiness (difficulty concentrating). Independent variables included sociodemographic and behavioral characteristics. Adjusted analyses were performed with Poisson regression. Of the 1,865 students, 32% exhibited insufficient sleep on class days, 8.2% insufficient sleep on weekends, 18.6% long latency on class days, 17.2% long latency on weekends, 30% low self-rated sleep quality, 12.7% nocturnal awakenings, and 32.2% daytime sleepiness. Higher alcohol consumption was associated with insufficient sleep duration and long latency on class days, low quality sleep, awakenings, and daytime sleepiness. Smoking was associated with insufficient sleep duration on weekends, awakenings, and low-quality sleep. Black and brown skin color were associated with insufficient sleep duration on class days, low-quality sleep, and awakenings. Morning classes were associated with insufficient sleep and daytime sleepiness. Female gender was associated with low-quality sleep and awakenings. The most frequent sleep disorders were insufficient sleep on class days, low self-rated quality of sleep, and daytime sleepiness. Alcohol consumption and smoking and black and brown skin color were the principal factors associated with sleep disorders.

The association of sleep disturbances with glycemia and obesity in youth at risk for or with recently diagnosed type 2 diabetes

OBJECTIVE

Poor sleep may increase obesity and type 2 diabetes (T2D) risk in youth. We explored whether subjective sleep duration, sleep quality, or risk for obstructive sleep apnea (OSA) are associated with glycemia, body mass index (BMI), or blood pressure (BP) in overweight/obese youth.

METHODS

Two-hundred and fourteen overweight/obese youth of 10 to 19 years of age at risk for or recently diagnosed with T2D who were screened for the Restoring Insulin Secretion (RISE) Study had a 2-hour oral glucose tolerance test (OGTT) and completed a Cleveland Adolescent Sleepiness questionnaire and a Sleep Disturbances Scale questionnaire. Independent associations between sleep variables and measures of glycemia, BMI, and BP were evaluated with regression models.

RESULTS

The multiethnic cohort was 67% female, 14.1 ± 2.1 years, and BMI 35.9 ± 6.5 kg/m² . Habitual sleep duration <8 hours was reported in 74%. Daytime sleepiness was reported in 51%, poor sleep quality in 26%, and 30% had high obstructive sleep apnea (OSA) risk. Daytime sleepiness was associated with higher HbA1c (0.2%, P = .02) and 2-hour glucose (13.6 mg/dL, P < .05). Sleep duration, sleep quality, and OSA risk were not associated with the evaluated outcomes. Poor sleep quality and OSA risk were associated with higher BMI (2.9 kg/m² , P = .004 and 2.83 kg/m² , P < .003, respectively).

CONCLUSIONS

In overweight/obese youth with or at risk for T2D, daytime sleepiness was associated with higher HbA1c. In addition, poor sleep quality and OSA risk were associated with higher BMI. These findings support intervention studies aimed at improving sleep quality in obese youth.

Behavioral, contextual and biological factors associated with obesity during adolescence: A systematic review

INTRODUCTION/OBJECTIVE

Adolescence is a critical period for the development of obesity. Obesity arises from a complex interaction between several factors, which are not yet fully understood. Therefore, the purpose of this review was to identify and assess the peer-reviewed scientific literature on the behavioral, contextual and biological factors associated with obesity in adolescents.

METHODS

PubMed and Scopus were systematically searched to identify prospective cohort studies concerning the relation between behavioral, contextual and biological factors and obesity in adolescents aged 10 to 18 years.

RESULTS

40 studies published between the year 2000 and 2018 were included. A positive consistent association between genetic factors and obesity during adolescence was found. Also, there is evidence to support the association between socioeconomic status and obesity. There was conflicting evidence for the contribution of dietary intake, physical activity, sedentary behavior, sleep, food store environment, school food environment. For the remaining factors no associations were found, or no conclusions could be drawn due to the limited number of studies identified.

CONCLUSIONS

Further prospective studies that assess multiple obesity determinants simultaneously and use state-of-art measures are warranted to aid in the development of effective strategies and interventions to prevent obesity during adolescence.

Effect of Sleep Duration, Diet, and Physical Activity on Obesity and Overweight Elementary School Students in Shanghai

BACKGROUND

This was a cross-sectional survey to investigate the relationship of age, parent education, sleep duration, physical activity, and dietary habits with overweight or obesity in school-age children in Shanghai.

METHODS

The survey gathered information from 13,001 children in grades 1 through 5 (age 6 to 10 years) among 26 elementary schools in 7 districts. Activity level was evaluated using the International Children's Leisure Activities Study Survey Questionnaire (CLASS-C). The definitions of normal, overweight, and obese were adjusted for each age.

RESULTS

Logistic regression analysis indicated that age, being male, having ≤10 hours of sleep on non-school days, eating ≥1 vegetable/day, or drinking ≥1 sugar-sweetened drink/day increased the risk for a child being overweight or obese compared with having >10 hours of sleep or ≤3 vegetables or ≤3 sugar-sweetened drinks/month (p ≤ .008). Having >2 hours of outdoor activities on non-school days reduced the risk of being overweight or obese compared with ≤2 hours of outdoor activities on non-school days (p < .001).

CONCLUSIONS

We found that age, sex, sleep, and some dietary habits impacted weight, and suggests that specific cultural and economic factors may impact risk of a child being overweight or obese.

Physical Activity, TV Watching Time, Sleeping, and Risk of Obesity and Hyperglycemia in the Offspring of Mothers with Gestational Diabetes Mellitus

We investigated the association of physical activity, TV watching time, sleeping time with the risks of obesity and hyperglycemia among 1263 offspring aged 1-5 years of mothers with gestational diabetes (GDM) in a cross-sectional study. Logistic regression models were used to obtain the odd ratios (ORs) (95% confidence intervals [CI]) of childhood obesity and hyperglycemia associated with different levels of indoor activity, outdoor activity, TV watching, and sleeping time. The multivariable-adjusted ORs of obesity based on different levels of TV watching time (0, <1.0, and ≥1.0 hour/day) were 1.00, 1.21 (95% CI 0.72-2.05), and 2.20 (95% CI 1.33-3.63) (P_trend = 0.003), respectively. The multivariable-adjusted ORs of hyperglycemia based on different levels of indoor activity (<5.0, 5.0-6.9, and ≥7.0 hours/day) were 1.00, 0.74 (95% CI 0.45-1.21), and 0.49 (95% CI 0.28-0.84) (P_trend = 0.034), respectively. The multivariable-adjusted ORs of hyperglycemia associated with different levels of sleeping time (<11.0, 11.0-11.9, and ≥12.0 hours/day) were 1.00, 0.67 (95% CI 0.42-1.05), and 0.39 (95% CI 0.23-0.67) (P_trend = 0.003), respectively. The present study indicated a positive association of TV watching with the risk of obesity, and an inverse association of either indoor activity or sleeping time with the risk of hyperglycemia among offspring born to GDM mothers in Tianjin, China.

Insomnia and obesity

PURPOSE OF REVIEW

Accumulating data suggest that short sleep plays a role in the development of obesity in general population. Insomnia disorder is characterized by short sleep and may persist for years. The question whether these patients have a higher risk of obesity is of socioeconomic as well as therapeutic interest.

RECENT FINDINGS

Numerous recently published cross-sectional and longitudinal studies show positive as well as negative associations between short sleep and overweight. Critical reviews note several methodological limitations that weaken the assumption of short sleep duration as the potential cause for obesity. From a sleep medical perspective, a basic methodological problem is the lack of a biological cut-off for short sleep duration. Therefore, recent findings on the relation between emotional stress in short sleepers and incident of obesity opens a more promising perspective on sleep quality as a possible factor. A few studies on patients with insomnia disorder, however, do not show higher BMIs adding data to a research puzzle.

SUMMARY

The relation of sleep duration and incident obesity so far has insufficient evidence base. Few data on patients with insomnia disorder do not confirm the association. Further research is necessary with focus on sleep quality instead of sleep duration.

The Origins of Mental Toughness - Prosocial Behavior and Low Internalizing and Externalizing Problems at Age 5 Predict Higher Mental Toughness Scores at Age 14

Background: The concept of mental toughness (MT) has gained increasing importance among groups other than elite athletes by virtue of its psychological importance and explanatory power for a broad range of health-related behaviors. However, no study has focused so far on the psychological origins of MT. Therefore, the aims of the present study were: to explore, to what extent the psychological profiles of preschoolers aged five were associated with both (1) MT scores and (2) sleep disturbances at age 14, and 3) to explore possible gender differences.

Method: Nine years after their first assessment at age five (preschoolers), a total of 77 adolescents (mean age: 14.35 years; SD = 1.22; 42% females) took part in this follow-up study. At baseline, both parents and teachers completed the Strengths and Difficulties Questionnaire (SDQ), covering internalizing and externalizing problems, hyperactivity, negative peer relationships, and prosocial behavior. At follow-up, participants completed a booklet of questionnaires covering socio-demographic data, MT, and sleep disturbances.

Results: Higher prosocial behavior, lower negative peer relationships, and lower internalizing and externalizing problems at age five, as rated by parents and teachers, were associated with self-reported higher MT and lower sleep disturbances at age 14. At age 14, and relative to males, females had lower MT scores and reported more sleep disturbances.

Conclusion: The pattern of results suggests that MT traits during adolescence may have their origins in the pre-school years.