Sleep Patterns and Obesity: Hispanic Community Health Study/Study of Latinos Sueño Ancillar Study

Napping and Obesity in Adults - What do we Know?

PURPOSE OF REVIEW

To review the evidence on the relationship between daytime napping and obesity.

RECENT FINDINGS

There is concern that napping may be harmful to metabolic health. Prospective studies have shown long time daytime napping (> 1 h) is associated with increased diabetes risk which may be partly associated with obesity. Evidence from numerous cross-sectional studies and meta-analyses of cross-sectional studies have shown that long time napping (> 1 h) but not short time napping is associated with increased risk of obesity, and this is seen worldwide. Inference regarding the nature of association from cross-sectional studies is limited; it is suggested the association is bidirectional. Prospective studies on the association between daytime napping and obesity are few and results unclear. Large longitudinal studies integrating daytime napping duration and night-time sleep behaviour and detailed information on lifestyle influences is needed to help elucidate further the associations of long time napping with obesity.

Association of insomnia and daytime napping with metabolic syndrome and its components in a Korean population: an analysis of data from the Korean Genome and Epidemiology Study

OBJECTIVES

We investigated the association between metabolic syndrome (MetS) and the coexistence of insomnia and daytime napping, because limited data have been reported regarding this association.

METHODS

The study population was 8,440 participants aged 40-65 years, who were from the Korean Genome and Epidemiology Study. Self-reported information on insomnia symptoms and nap duration was used to define exposure variables. Data on waist circumference (WC), blood pressure (BP), and fasting blood glucose (FBG), triglyceride (TG), and high-density lipoprotein cholesterol levels in blood were used to define MetS. Multivariate logistic regression analysis was performed to obtain odds ratio (OR) and 95% confidence interval (CI).

RESULTS

In multivariate logistic regression analysis, the coexistence of insomnia and napping was not significantly associated with MetS. However, the insomnia and non-napping group showed higher ORs of high TG (OR, 1.19; 95% CI, 1.02 to 1.39) and high BP (OR, 1.28; 95% CI, 1.10 to 1.49) than the non-insomnia and non-napping group. The combination of non-insomnia and napping and that of insomnia and napping showed higher ORs of high TG (OR, 1.13; 95% CI, 1.00 to 1.29) and high FBG (OR, 1.59; 95% CI, 1.14 to 2.21), respectively. In analyses of insomnia symptoms, only the combination of difficulty in maintaining sleep (DMS) and non-napping showed a higher OR for MetS (OR, 1.25; 95% CI, 1.03 to 1.52) than the non-DMS and non-napping group.

CONCLUSIONS

Individuals with insomnia, particularly those who do not take naps, were disproportionately likely to have MetS components, especially TG or BP. Information on these variables may help predict individuals' vulnerability to specific MetS components.

Risk Factors for Cardiovascular Disease: Knowledge Gained from the Hispanic Community Health Study/Study of Latinos

PURPOSE OF REVIEW

The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) has made important contributions on the prevalence of and factors associated with cardiovascular disease (CVD) risk factors among diverse Hispanic/Latino adults in the US. This article summarizes the knowledge gained thus far on major CVD risk factors from this landmark study.

RECENT FINDINGS

HCHS/SOL demonstrated the sizeable burdens of CVD risk in all major Hispanic/Latino groups in the US, as well as the marked variations in prevalence of hypertension, hypercholesterolemia, diabetes, obesity, and smoking by sex and background. It also identified sociodemographic, lifestyle, and sociocultural characteristics associated with risk factors. HCHS/SOL has yielded an expanding body of literature on characteristics associated with adverse CVD risk factors in this population. Long-term follow-up of this cohort will shed further light on the observed heterogeneity in CVD risk across Hispanic/Latino groups and identify specific risk/protective factors driving these variations.

Sleep-Body Composition Relationship: Roles of Sleep Behaviors in General and Abdominal Obesity in Chinese Adolescents Aged 17-22 Years

This study aimed to investigate the association between sleep behaviors and body composition, which was measured by bioelectrical impedance analysis (BIA) among Chinese adolescents. Overall, 444 students (65.3% females, 19.12 ± 1.177 years) completed questionnaires describing sleep characteristics. Sleep characteristics were derived from subjective means. Body composition was obtained from BIA by InBody 720 (Biospace Co. Ltd., Seoul, Republic of Korea). Regression models tested relationships between sleep and body composition after adjustment for covariates. Students with weekday nap duration (>30 min/d) exerted higher waist-height ratio (WHtR) (B = 0.013, FDR-corrected p = 0.080). Average sleep duration (≤7 h/d) was linked to more WHtR (B = 0.016, FDR-corrected p = 0.080). People with high social jetlag showed gained visceral fat area (B = 7.475), WHtR (B = 0.015), waist to hip ratio (B = 0.012), fat mass index (B = 0.663) and body fat percentage (B = 1.703) (all FDR-corrected p < 0.1). Individuals with screen time before sleep (>0.5 h) exhibited higher visceral fat area (B = 7.934, FDR-corrected p = 0.064), WHtR (B = 0.017, FDR-corrected p = 0.080), waist to hip ratio (B = 0.016, FDR-corrected p = 0.090), fat mass index (B = 0.902, FDR-corrected p = 0.069) and body fat percentage (B = 2.892, FDR-corrected p = 0.018). We found poor sleep characteristics were closely related to general and abdominal obesity.

Associations of multiple sleep dimensions with overall and abdominal obesity among children and adolescents: a population-based cross-sectional study

BACKGROUND

The relationship of insufficient sleep with the increased risk of obesity has been reported, but less is known about other sleep dimensions in the sleep-obesity associations.

OBJECTIVES

To assess the associations of multiple sleep dimensions with overall and abdominal obesity among Chinese students.

METHODS

This was a cross-sectional study involving 10,686 Han students aged 9-18 from Chinese National Survey on Students' Constitution and Health (CNSSCH). We collected sex, age, regions, parental educational levels, physical activity duration and sleep-related information by questionnaire survey, and also conducted anthropometric measurements including height, weight and waist circumference (WC). Unadjusted and adjusted binary logistic regression models were used to estimate the associations of sleep-related dimensions with obesity-related indicators.

RESULTS

Short sleep duration was associated with higher body mass index (BMI), larger WC and higher waist-to-height ratio (WHtR) in 9-12 and 16-18 age groups, whereas prolonged sleep duration on weekday was associated with higher BMI in 13-15 age group. Non-habitual midday napping and midday napping ≤0.5 h/d (vs 0.5 to 1 h/d) increased the risk of higher BMI in 13-15 age group, and the former was also associated with larger WC in 9-12 age group. Late bedtime was associated with larger WC and higher WHtR in 9-12 age group and with higher BMI and WHtR in 13-15 age group. Students aged 9-12 with social jet lag ≥2 h were found to have greater BMI after adjustment (Odds Ratio: 1.421; 95% confidence interval: 1.066-1.894).

CONCLUSIONS

Short or overlong sleep duration, late bedtime and great social jet lag were associated with higher prevalence of overall or abdominal obesity, while moderate midday napping can effectively decrease the risk. Those findings may assist in developing preventive strategies to combat obesity epidemic.

The relationship between daytime napping and obesity: a systematic review and meta-analysis

Daytime napping, a habit widely adopted globally, has an unclear association with obesity. In this study, we executed a meta-analysis to explore the relationship between daytime napping and obesity. We conducted a comprehensive search of the PubMed, Embase, Cochrane Library, Scopus, PsycINFO, and Web of Science databases for pertinent articles published up to April 2023. Random-effects models were utilized to calculate odds ratios (ORs) with 95% confidence intervals (CIs), and we assessed the heterogeneity of the included studies using the I² statistic. To explore potential sources of heterogeneity, subgroup analyses were performed. The methodological quality of the studies was evaluated using the Newcastle-Ottawa Scale (NOS), and funnel plots were employed to detect any publication bias. Sensitivity analyses were conducted by sequentially omitting each study. We conducted a meta-analysis of twelve studies that included one each from the UK and Spain, five from the USA, and five from China, totalling 170,134 participants, to probe the association between napping and obesity. The pooled analysis suggested a higher risk of obesity in individuals who nap (OR: 1.22 [1.10-1.35], p < 0.001, I² = 87%) compared to non-nappers. The meta-analysis results revealed variations in the summary ORs for studies conducted in China, Spain, the USA, and the UK. The ORs for China, Spain, the USA, and the UK were 1.05 (95% CI 0.90-1.23), 9.36 (95% CI 4.74-18.45), 1.27 (95% CI 1.10-1.47), and 1.39 (95% CI 1.32-1.47), respectively. A subgroup analysis based on age within the American population disclosed that napping in both adults and children heightened obesity incidence. A subgroup analysis based on nap duration found a significant rise in obesity occurrence when nap duration exceeded one hour, but no clear relationship emerged when nap duration was less than 1 h. In a subgroup analysis based on the definition of obesity, napping did not demonstrate a significant relationship with obesity when diagnostic criteria set obesity at a BMI of 25 or above. However, when the criteria were set at a BMI of 28 or 30 or more, napping significantly increased obesity risk. Our meta-analysis indicates a positive association between daytime napping and the risk of obesity. However, given the limited number of included studies, potential confounding factors might not have been fully addressed. Future well-designed prospective studies are required to further investigate this relationship. Large-scale studies are necessary to confirm our findings and elucidate the underlying mechanisms that drive these associations and causation.

The association between daytime napping and risk of type 2 diabetes is modulated by inflammation and adiposity: Evidence from 435 342 UK-Biobank participants

BACKGROUND

Existing evidence concerning the relationship between daytime napping and type 2 diabetes (T2D) is inconsistent, and whether the effects of napping differ by body fat percentage (BFP) and C-reactive protein (CRP) is unclear. We aimed to investigate the association between daytime napping frequency and T2D risk and whether such an association was modified by BFP and CRP.

METHODS

We included 435 342 participants free of diabetes from the UK Biobank. Participants were categorized as nonnappers, occasional nappers, and frequent nappers based on napping frequency, and BFP/CRP was divided into quartiles. Cox proportional hazards models were used.

RESULTS

During a median follow-up of 9.2 years, 17 592 T2D cases occurred. Higher frequency of daytime napping was significantly associated with an increased risk of T2D. Compared with nonnappers, the adjusted hazard ratios (HRs) for occasional nappers and habitual nappers were 1.28 (95% confidence interval [CI]: 1.24-1.32) and 1.49 (95% CI: 1.41-1.57), respectively. There was a significant additive and multiplicative interaction (relative excess risk due to interaction [RERI] = 0.490, 95% CI 0.307-0.673; p for multiplicative interaction <.001) between napping and BFP, whereby a higher hazard of T2D associated with more frequent napping was greatest among participants in the highest BFP quartile (HR = 4.45, 95% CI: 3.92-5.06). The results for CRP were similar (RERI = 0.266, 95% CI: 0.094-0.439; p for multiplicative interaction <.001).

CONCLUSIONS

Higher daytime napping frequency is associated with an increased T2D risk, and such relationships are modified by BFP and CRP. These findings underscore the importance of adiposity and inflammation control to mitigate diabetes risk.

Daytime napping and cardiovascular risk factors, cardiovascular disease, and mortality: A systematic review

Associations between night sleep duration and cardiovascular risk factors in adults have been well documented. However, the associations for daytime napping remain unclear. In this review, six databases were searched for eligible publications to April 8, 2022. A total of 11 articles were identified for umbrella review on the association of daytime napping with diabetes, metabolic syndrome (MetS), cardiovascular disease (CVD), and mortality in adults, 97 for systematic review on the association with CVD and several CVD risk factors. Our umbrella review showed that the associations of daytime napping with diabetes, MetS, CVD, and mortality in most meta-analyses were mainly supported by weak or suggestive evidence. Our systematic review showed that long daytime napping (≥1 h/d) was associated with higher odds of several CVD risk factors, CVD, and mortality, but no significant association was found between short daytime napping and most of the abovementioned outcomes. Our dose-response meta-analyses showed that daytime napping <30 min/d was not significantly associated with higher odds of most CVD risk factors and CVD among young and middle-aged adults. However, among older adults aged >60 years, we observed significant dose-response associations of daytime napping with higher odds of diabetes, dyslipidemia, MetS, and mortality starting from 0 min/d.

Systematic review: sleep health in the US Latinx population

Sleep disturbances are a common and unmet health problem in Latinx. While Latinx report similar sleep disturbances as non-Hispanic Whites [NHW], Latinx suffer from these disturbances to a greater degree than their NHW counterparts. Sleep disturbances are associated with increased risk of chronic health conditions, which Latinx experience at high rates. Research also points to significant sleep differences within Latinx. Given that Latinx are a rapidly growing population in the United States, sleep disparities between Latinx and NHWs and sleep differences within Latinx warrant further investigation. While research on Latinx sleep is growing, the last narrative review on US Latinx sleep health was published by Loredo and colleagues in 2010. Our narrative review expands on Loredo et al.'s work, adding the literature on Latinx sleep published since 2010 (N = 70). A total of 78 peer-reviewed articles related to young to middle-aged (i.e., 18-65 years) healthy Latinx adult sleep were identified in three databases-PsycInfo, PubMed/Medline, and Web of Science. With the socioecological model as framework, this review (1) summarizes current evidence pertaining to sleep health in healthy, community dwelling, urban Latinx adults; (2) discusses measurement challenges related to investigating Latinx sleep disparities and differences; and (3) discusses potential contributors to Latinx sleep. The prevalence of short sleep duration, long sleep duration, and poor sleep quality is high among Latinx; there are differences by Latinx subgroup. Our review identifies several multi-level influences associated with poor sleep: SES, sexual minority status, racial discrimination, access to care, neighborhood environment, and shift work. N = 250/250.

Obesity indicators as mediators of association between daytime napping and type 2 diabetes mellitus: the Guangzhou Biobank Cohort Study

OBJECTIVE

To examine the mediating effect of obesity indicators on the association between daytime napping and type 2 diabetes mellitus (T2DM) qualitatively and quantitatively using baseline data from the Guangzhou Biobank Cohort Study.

METHODS

Twenty-nine thousand three hundred fifty-five participants aged 50+ years were included in this cross-sectional study. Mediation analysis was used to assess the mediating effect of body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) on the association between daytime napping and T2DM after adjustment for sex, age, education, occupation, smoking status, alcohol use and physical activity.

RESULTS

The mean (standard deviation) age of participants was 61.5 ( 7.1) years. The prevalence of T2DM and daytime napping was 12.5% and 65.2%, respectively. After adjustment for potential confounders, WC, WHR and WHtR showed partial mediating effects on the association between daytime napping and T2DM, with the proportion (95% confidence interval) of mediation effect being 10.17% (8.14-14.43%), 14.91% (11.95-21.24%) and 9.36% (7.49-13.29%), respectively. No mediating effect of BMI or HC on the association between daytime napping and T2DM was found.

CONCLUSIONS

Our results showed significant mediating effects of WC, WHR and WHtR on the association between daytime napping and T2DM, suggesting that waist circumference management could be important in daytime nappers.

Factors associated with habitual sleep duration in US adults with hypertension: a cross-sectional study of the 2015-2018 National Health and Nutrition Examination Survey

Background

The relationship between inadequate sleep duration and hypertension risk has been established in the general population, but there is a gap in the literature on predictors of habitual sleep duration in adults with hypertension. This study examined factors associated with habitual sleep duration among adults with hypertension in the United States (US).

Methods

Data of 5660 adults with hypertension were obtained by combining the 2015–2018 cycles of the National Health and Nutrition Examination Survey (NHANES). Survey weighted multinomial logistic regression models were fit to examine factors associated with short (< 7 h) and long (> 9 h) sleep duration with adequate sleep duration (7–9 h) as the reference.

Results

The prevalence of self-reported adequate sleep duration was 65.7%, while short sleep duration was 23.6%, and long sleep duration 10.7%. Short sleep duration (compared to adequate sleep duration) was positively associated with history of seeking help for sleeping difficulties (relative risk ratio [RRR], 1.25; 95% confidence interval [CI], 1.02–1.53), Non-Hispanic Black race/ethnicity (RRR, 2.08; 95% CI, 1.61–2.67), working ≥45 h/week (RRR, 1.81; 95% CI, 1.32–2.48), and negatively associated with older age ≥ 65 years (RRR, 0.63; 95% CI, 0.45–0.91) and female gender (RRR, 0.70; 95% CI, 0.56–0.88). Long sleep duration was positively associated with female gender (RRR, 1.24; 95% CI, 1.001–1.54), chronic kidney disease (RRR, 1.48; 95% CI, 1.14–1.92), moderate depressive symptoms (RRR, 1.62; 95% CI, 1.08–2.44), moderately severe to severe depressive symptoms (RRR, 1.89; 95% CI, 1.05–3.43), being in retirement (RRR, 3.46; 95% CI, 2.18–5.49), and not working due to health reasons (RRR, 4.87; 95% CI, 2.89–8.22) or other reasons (RRR, 3.29; 95% CI, 1.84–5.88).

Conclusion

This population-based study identified factors independently associated with habitual sleep duration in adults with hypertension. These included help-seeking for sleeping difficulty, gender, age, chronic kidney disease, depressive symptoms, race/ethnicity, and employment status. These findings can help in the development of tailored approaches for promoting adequate sleep duration in adults with hypertension.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-12465-2.

Association Between Sleep Duration and Albuminuria in Patients with Type 2 Diabetes: A Cross-Sectional Study in Ningbo, China

PURPOSE

Type 2 diabetes mellitus (T2DM) can lead to microvascular complications including diabetic kidney disease. Albuminuria is an important marker to diagnose kidney injury in T2DM patients and healthy sleep duration is important for maintaining good health in patients with T2DM. However, the association between sleep duration and albuminuria in T2DM patients is unclear. Thus, this study aimed to investigate the association between sleep duration and albuminuria in patients with T2DM in Ningbo, China.

METHODS

A cross-sectional study was conducted at National Metabolic Management Centre (MMC) - Ningbo First Hospital from March 2018 to February 2021. Adult patients with T2DM were included in the study. The sleep duration (daytime and nocturnal) was self-reported. Albuminuria was defined as the presence of urinary albumin-creatinine ratio ≥30 mg/g. Logistic regression analyses were performed to identify the association.

RESULTS

There were 2688 T2DM patients in the study. In the unadjusted model (1), the odds of albuminuria increased with the daytime sleep duration (31-60 minutes: OR 1.36, 95% CI 1.09-1.71; ≥61 minutes: 1.73, 1.33-2.24). Similarly, after adjusting for age and sex (model 2), the odds of albuminuria increased with the daytime sleep duration (31-60 minutes: 1.34, 1.07-1.68; ≥61 minutes: 1.69, 1.30-2.20). After adjusting for age, sex, physical activity, smoking, alcohol drinking, overweight/obesity, hypertension, hyperuricaemia, duration of T2DM, glycated haemoglobin, angiotensin-converting enzyme inhibitors/angiotensin receptor blocker usage and nocturnal sleep duration (model 3), the odds of albuminuria increased with the daytime sleep duration (31-60 minutes: 1.33, 1.04-1.71; ≥61 minutes: 1.71, 1.29-2.26). However, no relationship was found between nocturnal sleep duration and albuminuria.

CONCLUSION

Longer daytime sleep is found to be associated with albuminuria in patients with T2DM in Ningbo, China but no association is found between nocturnal sleep duration and albuminuria. The findings are exploratory, and there is a need for longitudinal studies on this topic.

Risk of Developing Metabolic Syndrome Is Affected by Length of Daily Siesta: Results from a Prospective Cohort Study

Background: Siesta has been associated with increased incidence of cardiovascular disease but the mechanism remains unclear. New studies into the relationship between siesta and metabolic syndrome have identified siesta length as a crucial differential, suggesting that siesta less than 40 min is associated with decreased risk of metabolic syndrome, while longer siesta is associated with increased risk. We aimed to investigate the effect of siesta duration on development of metabolic syndrome in a Mediterranean population using a prospective cohort study design. Methods: Our sample consisted of 9161 participants of the SUN cohort without components of metabolic syndrome at baseline. Siesta exposure was assessed at baseline and the development of metabolic syndrome components was assessed after an average 6.8 years of follow-up. We estimated odds ratios and fitted logistic regression models to adjust for potential cofounders including night-time sleep duration and quality, as well as other diet, health, and lifestyle factors. Results: We observed a positive association between average daily siesta >30 min and development of metabolic syndrome (aOR = 1.39 CI: 1.03–1.88). We found no significant difference in risk of developing metabolic syndrome between the group averaging ≤30 min of daily siesta and the group not taking siesta (aOR = 1.07 CI: 0.83–1.37). Further analysis suggested that average daily siesta <15 min may reduce risk of metabolic syndrome. Conclusions: Our study supports the J-curve model of the association between siesta and risk of metabolic syndrome, but suggests the protective effect is limited to a shorter range of siesta length than previously proposed.

Association between daytime napping and obesity in Chinese middle-aged and older adults

Background

No studies have assessed the association between daytime napping and obesity in China. The study aimed to examine the association between daytime napping and obesity among Chinese middle-aged and older adults, and to evaluate the difference between the aforementioned association in men and women.

Methods

Overall, 14 685 participants aged 45 years and older were included by using data from China Health and Retirement Longitudinal Study (CHARLS) in 2015. A multivariable logistic regression model was used to investigate the relationship between daytime napping and obesity after adjusting for potential confounders. Stratified analyses were performed to examine the association differences by sex. Besides, the Cochran-Armitage test for trend was used to detect if there was a significant dose-response relationship between daytime napping and obesity.

Results

The mean age of participants was 60.32, and the mean daytime napping duration was 38.97 minutes. In the sample, compared with no daytime napping group, the risks of being obese were higher in both moderate daytime napping group (1-60 minute/d) (odds ratio OR = 1.27, 95% confidence interval (CI) = 1.13-1.44) and extend long daytime napping group (>60 minute/d) (OR = 1.34, 95% CI = 1.15-1.56). In sex stratification, these significant correlations only existed in women but not in men. Compared with no daytime napping, women who napped 1-60 minute/d and over 60 minute/d were more likely to be obese (OR = 1.37, 95% CI = 1.18-1.59 and OR = 1.49, 95% CI = 1.23-1.81, respectively). Besides, the Cochran-Armitage trend test revealed that the prevalence rate of obesity increased as the daytime napping duration increased (P < 0.001).

Conclusions

The study established the relationship between daytime napping and obesity in a general Chinese population. The association, however, was only detected among women. Furthermore, there was a dose-response relationship between daytime napping and obesity among women. Future studies may verify this association by using a longitudinal design and focus on the mechanisms behind such association.

Sleep fragmentation and the risk of obesity: The Sleep Heart Health Study

OBJECTIVE

Sleep disturbances have been recognized as a risk factor for obesity. This study used polysomnography records to investigate associations between sleep fragmentation and obesity.

METHODS

Objectively measured sleep fragmentation data recorded by in-home polysomnography, including total arousal index (ArI-total), ArI in rapid eye movement (REM) sleep (ArI-REM), ArI in non-REM sleep (ArI-NREM), sleep fragmentation index, sleep efficiency (SE), and wake after sleep onset (WASO), were based on the Sleep Heart Health Study (2,835 men and 2,888 women with a mean [SD] age of 63.2 [11.2] years). Multivariable regression analyses were used to examine the relationship between sleep fragmentation and obesity.

RESULTS

Multinomial logistic regression showed that participants with obesity have a significantly higher ArI-total (odds ratio [OR] 1.018; 95% CI: 1.010-1.026, p < 0.001), ArI-REM (OR 1.010; 95% CI: 1.002-1.018, p = 0.009), ArI-NREM (OR 1.017; 95% CI: 1.009-1.024, p < 0.001), and WASO (OR 1.003; 95% CI: 1.001-1.005, p = 0.007) compared with those with normal weight. Furthermore, multiple linear regression analyses showed an obvious correlation between ArI-total, ArI-REM, ArI-NREM, SE, WASO, and BMI.

CONCLUSIONS

The results revealed that ArI-total, ArI-REM, ArI-NREM, SE, and WASO were associated with obesity. The improvement of sleep fragmentation may contribute to decreasing the risk of obesity.

Modifying pathways by age and sex for the association between combined sleep disordered breathing and long sleep duration with neurocognitive decline in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

INTRODUCTION

We aimed to determine whether obesity or metabolic syndrome (MetS) modify associations between sleep-disordered breathing (SDB), self-reported sleep duration (SD), and phenotypes of combined SDB/SD with 7-year neurocognitive decline (ND) in a community based-cohort of U.S. Hispanic/Latinos (N = 5500) in different age and sex groups.

METHODS

The exposures were baseline SDB (respiratory event index ≥ 15), sleepiness (Epworth Sleepiness Scale ≥ 10), SD (< 6 hours, 6-9 hours, ≥ 9 hours). The outcome was 7-year ND.

RESULTS

Mean age was 56.0 years, 54.8% were females. Obesity modified the association between SDB/SD and ND in memory (F = 21.49, P < 0.001) and global cognition (F = 9.14, P < 0.001) in the oldest age group. Women without MetS with combined long sleep/SDB exhibited most pronounced decline in global cognition (F = 3.07, P = 0.010).

DISCUSSION

The association between combined SDB/long sleep and declines in memory and global cognition was most pronounced in obese older adults. Among women, MetS status modified the association between long sleep/SDB and decline in global cognition.

The association of sleep duration and feeling rested with health in U.S. Hispanic women

This study aims to understand the health correlates of sleep deficiencies in non-elderly U.S. Hispanic¹ women. Data from a sample of U.S. Hispanic women (n = 1531; ages 18-65 [M = 39.98; SD = 12.85]) who completed the 2017 National Health Interview Survey were analyzed to understand (1) sleep duration and quality; (2) the association of sleep patterns with key health indicators; and (3) whether these relationships are mediated by health behaviors (ie, healthy eating and physical activity). Shorter sleep duration was associated with a higher likelihood of often feeling anxious and having hypertension. Worse sleep quality was associated with a higher likelihood of being overweight, having fair or poor health status, often feeling depressed, often feeling anxious, having high cholesterol, and having asthma. Doctor's recommendation to engage in physical activity and to decrease calorie intake served as mediators in some of these relationships. Results indicate that among Hispanic women: (1) sleep is an important determinant of a variety of health outcomes and (2) the association of sleep and many health outcomes are mediated by healthy eating and physical activity. Further research on the association of sleep and risk of chronic disease among Hispanic women is needed.

Nocturnal awakenings of Brazilian immigrants in Massachusetts

OBJECTIVE

The purpose of this study was to assess the relationship between the quantity of jobs and nocturnal awakenings of Brazilians living in Massachusetts.

MATERIAL AND METHODS

We sampled of 48 documented Brazilians around the age of 45.5 years old. 52.1% of them were women. Data gathering occurred for three weeks, using the Pittsburgh Sleep Quality Index. Participants also wore wrist actigraph and filled sleep/wake diary for a week.

RESULTS

The sleep quality of immigrants with one job (mean=8.58, SD=4.16) is better when compared to immigrants with 2-3 jobs (mean=12.7, SD=3.57) according to the PSQI scores. Immigrants with 2-3 jobs reported dissatisfaction on three components of the scale: sleep duration, sleep efficiency and sleep quality.

DISCUSSION

There is a positive relationship between the quantity of jobs and nocturnal awakenings and between nocturnal awakenings and complaints related to sleep apnea among Brazilians in Massachusetts. The assessment of systemic morbidities associated with sleep pattern changes should be considered in future research.

Relationships of Sleep Duration, Midpoint, and Variability with Physical Activity in the HCHS/SOL Sueño Ancillary Study

OBJECTIVE/BACKGROUND

Short and long sleep duration, later sleep midpoint, and greater intra-individual sleep variability are associated with lower physical activity, but previous research lacks objective and concurrent assessment of sleep and physical activity. This cross-sectional study examined whether sleep duration, midpoint, and variability in duration and midpoint were related to wrist actigraphy-measured physical activity.

PARTICIPANTS

Participants were 2156 Hispanics/Latinos in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) Sueño Ancillary Study.

METHODS

Participants wore Actiwatch devices to measure sleep and physical activity via the wrist for ≥5 days. Physical activity was defined as minutes/day in the upper quartile of the sampling distribution's non-sleep activity, capturing light to vigorous physical activity.

RESULTS

An inverse linear relationship between sleep duration and physical activity was found such that each additional sleep hour related to 29 fewer minutes of physical activity (B = -28.7, SE = 3.8), p < .01). Variability in sleep midpoint was also associated with physical activity; with each 1-hr increase in variability there were 24 more minutes of physical activity (B = 24.2, SE = 5.6, p < .01). In contrast, sleep midpoint and variability in duration were not associated with physical activity. Sensitivity analyses identified an association of short sleep duration and greater variability in sleep duration with greater accelerometry-derived moderate-to-vigorous physical activity measured at the HCHS/SOL baseline (M = 2.1 years before the sleep assessment).

CONCLUSIONS

Findings help clarify inconsistent prior research associating short sleep duration and sleep variability with greater health risks but also contribute novel information with simultaneous objective assessments.

Circadian Melatonin Secretion In Obese Adolescents With Or Without Obstructive Sleep Apnea

Objective — To compare melatonin levels in saliva during a 24-hr day in order to identify the specificities of circadian melatonin secretion in obese adolescents with or without obstructive sleep apnea (OSA). Material and Methods — We examined 18 obese adolescents with OSA, 12 obese adolescents without OSA, and 15 healthy adolescents with a normal body weight, from whom saliva was sampled four time during the 24-hr day. Polysomnography was used to diagnose OSA. Saliva samples (n=180) were subjected to enzyme-linked immunosorbent assay. Results — Obese adolescents with OSA had higher evening melatonin levels than obese adolescents without OSA. For example, this indicator in OSA patients was 5.3 times higher than in participants without OSA, who had the lowest evening melatonin level among all groups. In both obese groups, nighttime melatonin levels were significantly lower than in the control group. A positive correlation was detected between the levels of morning and afternoon melatonin and body mass index only in obese adolescents without OSA (r=0.58; p=0.03 and r=0.68; p=0.01, respectively). It was found that evening melatonin correlated with minimum blood oxygen saturation (SaO2) in the entire sample of adolescents with OSA (r=-0.69; p=0.008), and it also correlated with time with SaO2 <90% in the group with clinical manifestations of OSA (r=0.76; p=0.003). Nighttime melatonin levels negatively correlated with the minimum SaO2 value solely in the group with clinical manifestations of OSA (r=-0.58; p=0.035). Conclusion — The circadian melatonin secretion in obese adolescents differed, depending on the presence or absence of OSA, and correlated with the level of oxygen desaturation in OSA patients, to a greater extent – in the presence of clinical manifestations.

Neighborhoods to Nucleotides - Advances and gaps for an obesity disparities systems epidemiology model

Purpose of Review

Disparities in obesity rates in the US continue to increase. Here we review progress and highlight gaps in understanding disparities in obesity with a focus on the Hispanic/Latino population from a systems epidemiology framework. We review seven domains: environment, behavior, biomarkers, nutrition, microbiome, genomics, and epigenomics/transcriptomics. We focus on recent advances that include at least two or more of these domains, and then provide a real world example of data collection efforts that reflect these domains.

Recent Findings

Research into DNA methylation related to discrimination and microbiome relating to eating behaviors and food content is furthering understanding of why disparities in obesity persist. Environmental and neighborhood level research is uncovering the importance of exposures such as air and noise pollution and systematic or structural racism for obesity and related outcomes through behaviors such as sleep.

Long Daytime Napping Is Associated with Increased Adiposity and Type 2 Diabetes in an Elderly Population with Metabolic Syndrome

Research examining associations between objectively-measured napping time and type 2 diabetes (T2D) is lacking. This study aimed to evaluate daytime napping in relation to T2D and adiposity measures in elderly individuals from the Mediterranean region. A cross-sectional analysis of baseline data from 2190 elderly participants with overweight/obesity and metabolic syndrome, in the PREDIMED-Plus trial, was carried out. Accelerometer-derived napping was measured. Prevalence ratios (PR) and 95% confidence intervals (CI) for T2D were obtained using multivariable-adjusted Cox regression with constant time. Linear regression models were fitted to examine associations of napping with body mass index (BMI) and waist circumference (WC). Participants napping ≥90 min had a higher prevalence of T2D (PR 1.37 (1.06, 1.78)) compared with those napping 5 to <30 min per day. Significant positive associations with BMI and WC were found in those participants napping ≥30 min as compared to those napping 5 to <30 min per day. The findings of this study suggest that longer daytime napping is associated with higher T2D prevalence and greater adiposity measures in an elderly Spanish population at high cardiovascular risk.