Is self-reported short sleep duration associated with obesity? A systematic review and meta-analysis of cohort studies

Association of sleep duration with Visceral Adiposity Index: a cross-sectional study based on the NHANES 2007-2018

OBJECTIVE

We aimed to assess the associations between sleep duration and Visceral Adiposity Index (VAI).

DESIGN

Cross-sectional study.

SETTING

The National Health and Nutrition Examination Survey (2007-2018).

PARTICIPANTS

A total 11 252 eligible participants who have complete information for sleep duration and VAI.

OUTCOME MEASURE

The VAI index, which is sex-specific and takes into consideration factors such as waist circumference, body mass index, high-density lipoprotein cholesterol and triglycerides, was calculated in accordance with prior research. Multiple linear regressions and subgroup analyses were employed to evaluate the connection between the duration of sleep and the VAI.

RESULTS

The mean sleep duration and VAI of included participants were 7.05 hours/day and 2.03, respectively. After adjusting for the sociodemographic, lifestyle and other covariates, short sleep was significantly linked to increased VAI (β=0.15, 95% CI 0.01 to 0.28) in relation to middle sleep duration, whereas no significant association was found between long sleep duration and VAI. An L-shaped relationship was observed between sleep duration and VAI. When sleep duration was less than 7.5 hours/day, a negative association between sleep duration and VAI was obvious. However, when sleep duration was >7.5 hours/day, VAI was increased with a longer sleep duration, although it was not significant.

CONCLUSIONS

An L-shaped relationship was observed between sleep duration and VAI, with insufficient sleep, being independently linked to a higher VAI. This implies that sleep deprivation might be associated with visceral adipose distribution and disfunction.

SGLT2 inhibition, circulating proteins, and insomnia: A mendelian randomization study

BACKGROUND

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) initially emerged as oral antidiabetic medication but were subsequently discovered to exhibit pleiotropic actions. Insomnia is a prevalent and debilitating sleep disorder. To date, the causality between SGLT2 inhibitors and insomnia remains unclear. This study aims to evaluate the causality between SGLT2 inhibitors and insomnia and identify potential plasma protein mediators.

METHODS

Using a two-sample Mendelian Randomization (MR) analysis, we estimated the causality of SGLT2 inhibition on insomnia and sleep duration. Additionally, employing a two-step and proteome-wide MR analysis, we evaluated the causal link of SGLT2 inhibition on 4907 circulating proteins and the causality of SGLT2 inhibition-driven plasma proteins on insomnia. We applied a false discovery rate (FDR) correction for multiple comparisons. Furthermore, mediation analyses were used to identify plasma proteins that mediate the effects of SGLT2 inhibition on insomnia.

RESULTS

SGLT2 inhibition was negatively correlated with insomnia (odds ratio [OR] = 0.791, 95 % confidence interval [CI] [0.715, 0.876], P = 5.579*10^-6) and positively correlated with sleep duration (β = 0.186, 95 % CI [0.059, 0.314], P = 0.004). Among the 4907 circulating proteins, diadenosine tetraphosphatase (Ap4A) was identified as being linked to both SGLT2 inhibition and insomnia. Mediation analysis indicated that the effect of SGLT2 inhibition on insomnia partially operates through Ap4A (β = -0.018, 95 % CI [-0.036, -0.005], P = 0.023), with a mediation proportion of 7.7 %.

CONCLUSION

The study indicated a causality between SGLT2 inhibition and insomnia, with plasma Ap4A potentially serving as a mediator.

Association between evacuation and becoming overweight after the Great East Japan Earthquake: a 7-year follow-up of the Fukushima Health Management Survey

OBJECTIVES

Disaster evacuation increases the risk of becoming overweight or obese owing to lifestyle changes and psychosocial factors. This study evaluated the effect of evacuation on becoming overweight during a 7-year follow-up among residents of Fukushima Prefecture during the Great East Japan Earthquake.

STUDY DESIGN

This was a prospective cohort study.

METHODS

We analysed data collected from 18,977 non-overweight Japanese participants who completed the 'Comprehensive Health Checkup Program' and 'Mental Health and Lifestyle Survey', as part of the Fukushima Health Management Survey, between July 2011 and November 2012. An evacuation was defined as the moving out of residents of municipalities designated as an evacuation zone by the government or having a self-reported experience of moving into shelters or temporary housing. Follow-up examinations were conducted in March 2018 to identify patients who became overweight. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated using a Cox proportional hazards regression model.

RESULTS

Among 15,875 participants (6091 men and 9784 women; mean age 63.0 ± 11.1 years) who received follow-up examination (mean follow-up, 4.29 years), 2042 (856 men and 1186 women) became overweight. Age-, baseline body mass index-, lifestyle-, and psychosocial status-adjusted HRs (95% CIs) for becoming overweight after evacuation were 1.44 (1.24-1.66) for men and 1.66 (1.47-1.89) for women.

CONCLUSION

Evacuation was associated with the risk of becoming overweight 7 years after the disaster. Thus, maintaining physical activity, healthy diet, and sleep quality and removing barriers to healthy behaviour caused by disasters, including anxiety concerning radiation, may prevent this health risk among evacuees.

Chronic Mild Sleep Restriction Does Not Lead to Marked Neuronal Alterations Compared With Maintained Adequate Sleep in Adults

BACKGROUND

Sleep restriction (SR) has been shown to upregulate neuronal reward networks in response to food stimuli, but prior studies were short-term and employed severe SR paradigms.

OBJECTIVE

Our goal was to determine whether mild SR, achieved by delaying bedtimes by 1.5 h, influences neuronal networks responsive to food stimuli compared with maintained adequate sleep (AS) >7 h/night.

METHODS

A randomized controlled crossover study with 2 6-wk phases, AS (≥7 h sleep/night) and SR (-1.5 h/night relative to screening), was conducted. Adults with AS duration, measured using wrist actigraphy over a 2-wk screening period, and self-reported good sleep quality were enrolled. Resting-state and food-stimulated functional neuroimaging (fMRI) was performed at the endpoint of each phase. Resting-state fMRI data analyses included a priori region-of-interest seed-based functional connectivity, whole-brain voxel-wise analyses, and network analyses. Food task-fMRI analyses compared brain activity patterns in response to food cues between conditions. Paired-sample t tests tested differences between conditions.

RESULTS

Twenty-six participants (16 males; age 29.6 ± 5.3 y, body mass index 26.9 ± 4.0 kg/m2) contributed complete data. Total sleep time was 7 h 30 ± 28 min/night during AS compared with 6 h 12 ± 26 min/night during SR. We employed different statistical approaches to replicate prior studies in the field and to apply more robust approaches that are currently advocated in the field. Using uncorrected P value of <0.01, cluster ≥10-voxel thresholds, we replicated prior findings of increased activation in response to foods in reward networks after SR compared with AS (right insula, right inferior frontal gyrus, and right supramarginal gyrus). These findings did not survive more rigorous analytical approaches (Gaussian Random Field theory correction at 2-tailed voxel P < 0.001, cluster P < 0.05).

CONCLUSIONS

The results suggest that mild SR leads to increased reward responsivity to foods but with low confidence given the failure to meet significance from rigorous statistical analyses. Further research is necessary to inform the mechanisms underlying the role of sleep on food intake regulation. This trial was registered at clinicaltrials.gov as NCT02960776.

Dietary polyphenols and sleep modulation: Current evidence and perspectives

Polyphenols are plant compounds with several biological activities. This review aims to summarize current knowledge on the potential role of polyphenols in modulating sleep. A total of 28 preclinical studies, 12 intervention studies and four observational studies exploring the role of polyphenol intake on sleep were identified. From animal studies, 26 out of the 28 studies found beneficial effects of polyphenols on sleep architecture. Three out of four human observational studies found a beneficial association between polyphenol intake and sleep parameters. And, among clinical intervention studies, eight from a total of 12 studies found some beneficial effect of polyphenol intake on various sleep parameters, although some discrepancies between studies were found. Overall, emerging evidence suggests a benefit of polyphenol intake on sleep. Several mechanisms of action have been suggested, ranging from effects on neurotransmitters to an action through the gut-brain axis. However, more research in this field is needed, emphasizing the use of nutritional doses in mechanistic studies and interventions targeting participants with sleep problems. This would allow to elucidate whether an additional biological effect of polyphenols is modulation of sleep, a behavior associated with adverse health outcomes.

Sleep deprivation in development of obesity, effects on appetite regulation, energy metabolism, and dietary choices

Sleep deprivation, which is a decrease in duration and quality of sleep, is a common problem in today's life. Epidemiological and interventional investigations have suggested a link between sleep deprivation and overweight/obesity. Sleep deprivation affects homeostatic and non-homoeostatic regulation of appetite, with the food reward system playing a dominant role. Factors such as sex and weight status affect this regulation; men and individuals with excess weight seem to be more sensitive to reward-driven and hedonistic regulation of food intake. Sleep deprivation may also affect weight through affecting physical activity and energy expenditure. In addition, sleep deprivation influences food selection and eating behaviours, which are mainly managed by the food reward system. Sleep-deprived individuals mostly crave for palatable energy-dense foods and have low desire for fruit and vegetables. Consumption of meals may not change but energy intake from snacks increases. The individuals have more desire for snacks with high sugar and saturated fat content. The relationship between sleep and the diet is mutual, implying that diet and eating behaviours also affect sleep duration and quality. Consuming healthy diets containing fruit and vegetables and food sources of protein and unsaturated fats and low quantities of saturated fat and sugar may be used as a diet strategy to improve sleep. Since the effects of sleep deficiency differ between animals and humans, only evidence from human subject studies has been included, controversies are discussed and the need for future investigations is highlighted.

Targeting microbiota to alleviate the harm caused by sleep deprivation

Sleep deprivation has become a common health hazard, affecting 37-58% of the population and promoting the occurrence and development of many diseases. To date, effective treatment strategies are still elusive. Accumulating evidence indicates that modulating the intestinal microbiota harbors significant potential for alleviating the deleterious impacts of sleep deprivation. This paper first reviews the effects of sleep deprivation on gastrointestinal diseases, metabolic diseases, and neuropsychiatric diseases, discussing its specific mechanisms of influence. We then focus on summarizing existing interventions, including probiotics, melatonin, prebiotics, diet, and fecal microbiota transplantation (FMT). Finally, we have discussed the advantages and limitations of each strategy. Compared with other strategies, probiotics showed a high potential in alleviating sleep deprivation-related hazards due to their reduced risk and high security. We suggest that future research should focus on the specific mechanisms by which probiotics mitigate the harms of sleep deprivation, such insights may unveil novel pathways for treating diseases exacerbated by insufficient sleep.

The interrelationship between sleep, diet, and glucose metabolism

Obesity and type 2 diabetes (T2D) are increasingly common worldwide. While these disorders have increased in prevalence over the past several decades, there has been a concomitant reduction in sleep duration. Short sleep duration has been associated with higher rates of obesity and T2D, and the causality of these associations and their directionality, continue to necessitate evaluation. In this review we consider the evidence that sleep is an intrinsic factor in the development of obesity and chronic metabolic disorders, such as insulin resistance and T2D, while evaluating a potential bi-directional association. We consider the evidence that diet and meal composition, which are known to impact glycemic control, may have both chronic and acute impact upon sleep. Moreover, we consider that postprandial nocturnal metabolism and peripheral glycemia may affect sleep quality. We propose putative mechanisms whereby acute effects of nighttime glucose excursions may lead to increased sleep fragmentation. We conclude that dietary manipulations, particularly with respect to carbohydrate quality, may confer sleep benefits. Future research may seek to evaluate the effectiveness of synergistic nutrient strategies to promote sleep quality, with particular attention to carbohydrate quality, quantity, and availability as well as carbohydrate to protein ratio.

Temporal relationship between sleep duration and obesity among Chinese Han people and ethnic minorities

BACKGROUND

No studies have assessed the association between sleep duration and obesity in Chinese ethnic minorities. Whether the relationship between sleep duration and obesity is different between Chinese Han people and Chinese ethnic minorities remains unclear. The study aimed to explore the relationship between sleep duration and obesity among Chinese Han people and Chinese ethnic minorities.

METHODS

We applied data from the Guizhou Population Health Cohort Study (GPHCS), which 9,280 participants were recruited in the baseline survey from 2010 to 2012, and 8,163 completed the follow-up survey from 2016 to 2020. A total of 5,096 participants (3,188 Han Chinese and 1,908 ethnic minorities) were included in the ultimate analysis. Information on sleep duration (total 24-hour sleep time), body mass index (BMI), and waist circumference (WC) was collected at the baseline and follow-up survey, respectively. Cross-lagged panel analyses were conducted to explore the temporal relationship between sleep duration and obesity for Han people and ethnic minorities.

RESULTS

For Han people, the results from cross-lagged panel analyses indicated that baseline sleep duration was significantly associated with follow-up BMI (β_BMI = -0.041, 95% CI_BMI: -0.072 ~ -0.009) and follow-up WC (β_WC = -0.070, 95%CI_WC: -0.103 ~ -0.038), but baseline BMI (β_BMI = -0.016, 95% CI_BMI: -0.050 ~ 0.018) and baseline WC (β_WC = -0.019, 95% CI_WC: -0.053 ~ 0.016) were not associated with follow-up sleep duration. In addition, the relationship between baseline sleep duration and follow-up BMI was gender-specific and significant only in the Han people female (β_BMI = -0.047, 95% CI_BMI: -0.090 ~ -0.003) but not in the Han people male (β_BMI = -0.029, 95% CI_BMI: -0.075 ~ 0.016). For ethnic minorities, the results indicated that there was no relationship between sleep duration and obesity at all, either from sleep duration to obesity (β_BMI = 0.028, 95%CI_BMI: -0.012 ~ 0.068; β_WC = 0.020, 95%CI_WC: -0.022 ~ 0.062), or from obesity to sleep duration (β_BMI = -0.022, 95%CI_BMI: -0.067 ~ 0.022; β_WC = -0.042, 95%CI_WC: -0.087 ~ 0.003).

CONCLUSION

The relationship pattern between sleep duration and obesity across Han people and ethnic minorities is different. Future sleep-aimed overweight and obesity intervention should be conducted according to population characteristics.

Association of 3-year change in sleep duration with risk of all-cause mortality in Chinese older population: A national cohort study

BACKGROUND

Existing evidence on the association of dynamic change in sleep duration with risk of all-cause mortality in Chinese older population is limited. We aimed to explore the association of 3-year change in sleep duration with risk of all-cause mortality in a Chinese older population.

MATERIALS AND METHODS

A total of 5772 Chinese older participants (median age 82 years) were enrolled in the current study. Cox proportional-hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association of 3-year change in sleep duration with risk of all-cause mortality. Subgroup analyses of the association between 3-year change in sleep duration and risk of all-cause mortality were conducted by age, sex and residence.

RESULTS

During a median of 4.08 years of follow-up, death developed in 1762 participants. Compared with -1 to <1 h/day change in sleep duration, the adjusted risk of all-cause mortality with < -3 h/day change in sleep duration may increase 26% (HR = 1.26, 95% CI: 1.05-1.52); the risk of all-cause mortality with 3-year change from short to long sleep duration, or long to short sleep duration versus stable normal sleep duration status was increased about 28% and 52%, respectively (HR = 1.28, 95% CI: 1.00-1.64 and HR = 1.52, 95% CI: 1.21-1.92). Subgroup analyses demonstrated that similar significant associations were observed among participants with 65 to <85 years, men and living in city and town.

CONCLUSIONS

Dynamic sleep duration change was significantly associated with risk of all-cause mortality. The current study suggests that sleep duration may be a non-invasive indicator for interventions aiming to reduction risk of all-cause mortality in Chinese older population.

Exploring the Role of Dairy Products In Sleep Quality: From Population Studies to Mechanistic Evaluations

Poor sleep quality and insufficient sleep affect a large portion of the population. This is concerning given increasing evidence that poor sleep health is a behavioral risk factor for the development of cardiometabolic diseases. A healthy diet is associated with a plethora of favorable health outcomes, and emerging research now highlights diet as a potential determinant of sleep health that could be leveraged to improve sleep quality. Dairy products are notably rich in tryptophan (Trp), a key substrate for serotonin and melatonin production, which are instrumental for initiating and maintaining sleep. Furthermore, dairy products provide a range of micronutrients that serve as cofactors in the synthesis of melatonin from Trp, which could contribute to sleep-promoting effects. In this review, we evaluate population studies and clinical trials to examine a possible link between dairy consumption and sleep. Available epidemiologic studies illustrate positive associations between dairy intake and sleep outcomes. Moreover, some intervention studies support a causal effect of dairy intake on sleep. Given these data, we discuss potential mechanisms, invite additional clinical research on this topic, and provide insights on how limitations of current studies can be addressed in future trials.

Duração do sono autorrelatada e objetiva em pacientes com DRC: contam a mesma história?

Resumo Introdução: Há discordância entre os dados sobre duração do sono obtidos a partir de questionários e medições objetivas. Não se sabe se isto também é verdade para indivíduos com DRC. Aqui comparamos a duração do sono autorrelatada com a duração do sono obtida por meio de actigrafia. Métodos: Este estudo prospectivo incluiu indivíduos adultos com DRC estadio 3 recrutados entre Setembro/2016 e Fevereiro/2019. Avaliamos a duração subjetiva do sono, fazendo a seguinte questão: “Quantas horas de sono real você teve à noite?” Resultados: Os pacientes (N=34) eram relativamente jovens (51 ± 13 anos). A duração do sono autorrelatada e mensurada foi de 7,1 ± 1,7 e 6,9 ± 1,6 horas, respectivamente, sem correlação entre elas (p=0,165). Embora a diferença média entre as medições tenha sido de 0,21 h, os limites de concordância variaram de -3,7 a 4,1 h. Conclusão: Pacientes com DRC que não estão em diálise apresentam uma percepção equivocada do sono. Dados sobre a duração do sono devem ser obtidos preferencialmente a partir de medições objetivas em pacientes com DRC.

Self-reported and objective sleep duration in patients with CKD: are they telling the same story?

Abstract Introduction: There is disagreement between data on sleep duration obtained from questionnaires and objective measurements. Whether this is also true for individuals with CKD is unknown. Here we compared self-reported sleep duration with sleep duration obtained by actigraphy. Methods: This prospective study included adult individuals with stage 3 CKD recruited between September/2016 and February/2019. We evaluated subjective sleep duration by asking the following question: “How many hours of actual sleep did you get at night?” Results: Patients (N=34) were relatively young (51 ± 13 years). Self-reported and measured sleep duration were 7.1 ± 1.7 and 6.9 ± 1.6 hours, respectively, with no correlation between them (p=0.165). Although the mean difference between measurements was 0.21 h, the limits of agreement ranged from -3.7 to 4.1 h. Conclusion: Patients with CKD who are not on dialysis have an erroneous sleep perception. Data on sleep duration should be preferentially obtained from objective measurements in patients with CKD.

Age and Sex Differences in the Association of Sleep Duration and Overweight/Obesity among Chinese Participants Age above 45 Years: A Cohort Study

OBJECTIVES

We aimed to evaluate the association between sleep duration and obesity and estimate the attributable risk of sleep in the China Health and Retirement Longitudinal Study surveys (CHARLS).

METHODS

A total of 9061 adults aged 45 years above from CHARLS (2011-2015) were included. The main outcome of this study was incident overweight/obesity specific to general and abdominal obesity. Overweight/obesity was defined as BMI ≥ 23.0 (kg/m2) and BMI≥27.5 (kg/m2), respectively. Abdominal obesity was defined as waist circumference ≥90 cm for men and ≥80 cm for women. Self-reported sleep durations were obtained using a structured questionnaire. We assessed hazard ratios (HRs) and 95% confidence intervals (CIs) as well as the population attributable fraction (PAF) for associations between sleep duration and obesity.

RESULTS

986 and 606 participants were identified as overweight and general obesity respectively, 1253 experienced abdominal obesity events. In multivariable-adjusted models, participants with daytime sleep of 0-30 minutes and more than 30 minutes associated with 30% (HR: 0.70, 95% CI: 0.56-0.87) and 35% (HR: 0.65, 95% CI: 0.55-0.78) decreased incident overweight risk respectively compared to those having no daytime sleep, this association also found among females and middle-aged, not males or elderly. Similarly, 0-30 minutes (HR: 0.68, 95% CI: 0.48-0.96) and more than 30 minutes of daytime sleep (HR: 0.73, 95% CI: 0.59-0.91) were associated with a reduced risk of abdominal obesity, similar results also found among females and middle-aged. Compared with 7-9 hours of nocturnal sleep, people who slept 5-7 hours had a reduced risk of overweight (HR: 0.59, 95% CI=0.47-0.74),but not found in subgroups. The hazard role of long nocturnal sleep for abdominal obesity was only found among elderly (HR: 2.33, 95% CI=1.35-4.04) and males (HR: 2.24, 95% CI=1.17-4.29). Compared with moderate total sleepers (7-9hours/day), participants with short total sleep duration exhibited an elevated risk of overweight (HR: 1.13, 95% CI=1.00-1.28), this also found among middle-aged. The PAF for inadequate total sleep duration (<7 hours/day) was 10.77% for overweight individuals.

CONCLUSIONS

Insufficient sleep duration was associated with an elevated risk of overweight only detected among middle-aged not elderly and other subgroups specific by age. The risks for abdominal obesity were increased for males and middle-aged with long nocturnal sleep. Daytime sleep may significantly reduce the risk of overweight and abdominal obesity in female and middle-aged individuals. The link between sleep duration and obesity requires further study.