Association of Nap Duration after Lunch with Prevalence of Metabolic Syndrome in a Chinese Government Employee Population

The mediating effect of sleep duration on metabolic syndrome severity in adults: a structural equation modeling approach

BACKGROUND

Metabolic syndrome (MetS) is associated to sleep duration. It is crucial to identify factors that disrupt sleep regulation. The study aimed to assess the indirect effect of risk factors related to MetS severity through sleep duration by utilizing a structural equation model (SEM).

METHODS

The study involving 3,935 adults from the baseline data of the Ravansar Non-Communicable Disease (RaNCD) cohort study. MetS severity scores were the outcome variables. SEM was employed to explore the relationships, utilizing IBM SPSS and AMOS version 23.

RESULTS

The mean MetS severity score was higher in women compared to men (0.25 vs. 0.16, P = 0.003). In men, socioeconomic status (SES) has a positive direct effect (β = 0.048) and a negative indirect effect (β=-0.006) on MetS severity. Increased physical activity is directly (β=-0.036) and indirectly (β=-0.093) associated with reducing MetS severity. Nap duration is directly linked to an increase (β = 0.072) but has an indirect effect (β=-0.008) in decreasing MetS severity. In women, SES has a direct (β=-0.020) and indirect (β=-0.001) inverse relationship with MetS severity. Increased physical activity is directly (β=-0.048) and indirectly (β=-0.036) associated with decreasing MetS severity in women. Nap duration is directly associated with an increase in MetS severity (β=-0.018) but indirectly contributes to its reduction (β=-0.002). Sleep duration not only directly affects MetS severity but is also influenced by age, SES, physical activity, obesity and nap duration.

CONCLUSION

Physical activity, SES, and nap duration directly and indirectly effect the MetS severity. Sleep duration was recognized as a mediating variable that supports the indirect effects.

Association between length of daily siesta and brachial-ankle pulse wave velocity (baPWV): a community-based cross sectional study in North China

INTRODUCTION

To date, many studies have shown a link between siesta and cardiovascular events. Little is known regarding the connection between siesta and brachial-ankle pulse wave velocity (baPWV) levels, even though baPWV can determine the degree of atherosclerosis and vascular stiffness. Thus, we examined the relationship between siesta time and baPWV in a cross-sectional study.

METHODS

Interviews, physical examinations, lab testing, and electron beam computed tomography were all part of the baseline evaluation for participants aged older than 35. Baseline data were compared for 3 different siesta habits: irregular or no siestas, daily short siestas (1 h or less), and daily long siestas (> 1 h). Utilizing logistic regression models and multivariate linear regression, the link between siesta time and baPWV was determined.

RESULTS

Among all 6566 participants, the different siesta groups had a significant difference of the degrees of AS (P < 0.001). The same outcome was true for both males (P < 0.001) and females (P < 0.001). Numerous cardiovascular risk variables and markers of subclinical atherosclerosis were positively correlated with daily extended siestas. Results from the fully adjusted model showed that long siestas (> 60 min, OR = 1.18, 95%CI: 1.06-1.31, P = 0.002) were linked to a more severe level of the baPWV. For age or gender stratification, we found significant differences between non-siesta and > 60 min siesta groups. Multiple linear regression analysis revealed a positive connection between siesta duration and baPWV (β = 0.197, P = 0.038).

CONCLUSIONS

An elevated risk of atherosclerosis was shown to accompany prolonged siestas. These results need to be followed up on with prospective studies and additional lab work.

The Way to Spend a Workday Matters in School Principals' Somatic and Psychological Discomfort

BACKGROUND

School principals usually have to sacrifice health and family obligations to obtain sufficient work time. This study investigates school principals' somatic and psychological discomfort related to their time allocation to diverse work contexts and life domains, so as to test the optimal allocation of time to each context and domain.

METHODS

This study is based on survey data of 347 school principals, from the preexisting 2021 Survey of School Teachers' Living Conditions in Shanghai. Generalized linear regression modeling was adopted to analyze the data according to the research purpose.

RESULTS

This study finds that school principals' daily time spent on work at home, sleep, breakfast, exercise, and family obligations significantly predict their somatic or psychological discomfort. However, their time spent on work at school, daytime napping, lunch, and dinner are not of significance.

CONCLUSIONS

This study reveals several unhealthy ways of working and lifestyle habits among school principals from a perspective of time allocation, such as extended periods working at home, sleep deficits, hurried breakfast, lack exercise, and failure to meet familial obligations.

High free triiodothyronine, and free-triiodothyronine-to-free-thyroxine ratio are associated with metabolic syndrome in a euthyroid employee population: the Zhejiang Zhenhai study

Objective

The aim of this study was to elaborate the link of thyroid hormones (THs) and metabolic syndrome (MetS) in a Chinese euthyroid employee population with MetS component(s).

Methods

An annual health checkup was performed on employees in 2019. Anthropometric parameters, metabolic parameters, and thyroid function were measured. A questionnaire was used in conjunction with Zhenhai Lianhua Hospital database to receive employees' medication records and thyroid surgical history records.

Results

A total of 5486 eligible employees were included; the prevalence of MetS was generally higher in males than in females (38.9 vs. 30.4%, P < 0.001). Among employees with central obesity, hypertriglyceridemia, hyperglycemia, hypertension, and low high-density lipoprotein cholesterol (HDL-C), the prevalence of MetS was 68.8, 63.6, 68.2, 48.8, and 60.0% in males and 72.6, 63.3, 61.3, 42.3, and 42.3% in females, respectively. Logistic regression analysis showed that thyroid-stimulating hormone and free thyroxine (FT4) quartiles had no significant impact on MetS. Free triiodothyronine/free thyroxine (FT3/FT4) and free triiodothyronine (FT3)) quartiles were positively associated with the increased odds ratio (OR) for MetS and dyslipidemia (hypertriglyceridemia and low HDL-C), regardless of gender. In males, FT3 and FT3/FT4 quartiles were positively associated with the OR for central obesity, whereas FT4 quartiles were negatively associated; both FT3 and FT4 quartiles were positively associated with increased OR of hyperglycemia, while similar results were not observed in females. Interaction analysis indicated no significant effect of gender and TH interactions on risk of MetS.

Conclusion

High FT3 and FT3/FT4 were strongly linked with MetS and dyslipidemia in our study, even in the euthyroid individuals. Tighter control of thyroid function was necessary for those with preexisting MetS component(s).

Bidirectional Associations between Daytime Napping Duration and Metabolic Syndrome: A Nationally Representative Cohort Study

BACKGROUND

We aimed to examine the bidirectional associations between daytime napping duration and metabolic syndrome (MetS).

METHODS

Using data from the China Health and Retirement Longitudinal Study from 2011 to 2015, modified Poisson regression models were performed to explore the longitudinal associations of baseline napping duration with the occurrence and remission of MetS. Generalized estimating equation was conducted to explore the association between baseline MetS status with subsequent changes in daytime napping duration. Cross-lagged panel analysis was performed to further verify their bidirectional relationships.

RESULTS

During the four-year follow-up, among 5041 participants without MetS at baseline, extended naps were significantly associated with MetS occurrence, compared with non-napping. This association was only significant in individuals with adequate night-time sleep duration or good sleep quality of the 2898 participants with MetS at baseline. Excessive napping duration may be not favorable for MetS remission especially for adequate night-time sleepers. With respect to reverse associations, baseline MetS status significantly increased the napping duration during the subsequent follow-up period. Finally, there were significant bidirectional cross-lagged associations between napping duration and MetS severity score after adjusting for all covariates.

CONCLUSIONS

Our study indicates bidirectional relationships exist between daytime napping duration and MetS. Interestingly, longer napping duration was detrimental to cardiometabolic health only in those with sufficient night-time sleep duration or good sleep quality.

Association between nocturnal sleep duration and the risk of hyperuricemia among Chinese government employees: A cross-sectional study

Objectives

Evidence has shown that nocturnal sleep duration is associated with the risk of hyperuricemia, yet the findings are inconsistent. Thus, we aimed at exploring the association between nocturnal sleep duration and the risk of hyperuricemia in Chinese government employees.

Methods

A total of 10,321 government employees aged 20-60 years were collected from the Cohort Study on Chronic Diseases among Government Employees in Hunan Province, China. Sleep duration was self-reported. And serum uric acid levels >420 μmol/L in men and >360 μmol/L in women were considered hyperuricemia. The association between nocturnal sleep duration and hyperuricemia risk was examined utilizing multivariate logistic regression models. To further examine the connection between nocturnal sleep duration and serum uric acid levels, multiple linear regression analyses were utilized.

Results

The prevalence of hyperuricemia was 17.2%. The results of logistic regression demonstrated that, in contrast to participants whose sleep duration was 7-8 h, those who slept for <7 h had an elevated risk of hyperuricemia (OR = 1.343, 95%CI: 1.126, 1.601). Further stratified analysis revealed that this association was still observed in those without obesity (OR = 1.365; 95%CI: 1.127, 1.655), hypertension (OR = 1.290, 95%CI: 1.054, 1.578), or diabetes mellitus (OR = 1.361, 95%CI: 1.136, 1.631). Multiple linear regression showed that shorter sleep duration (< 7 h) was positively correlated with serum uric acid levels. In comparison to individuals who slept for 7-8 h, those with sleep duration of fewer than 7 h had serum uric acid levels that were 7.231 μmol/L (95% CI: 2.875, 11.588) higher.

Conclusion

Short nocturnal sleep duration (< 7 h) was associated with a higher risk of hyperuricemia, especially in participants without obesity, hypertension, or diabetes mellitus. Besides, short nocturnal sleep duration was related to greater uric acid levels.

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.

The Association Between Life Events and Incidence of Hypertension Among Government Employees in China: A Prospective Cohort Study

Background

Hypertension (HTN) is a global public health concern. However, the association between life events (LEs) and HTN is complex. Thus, we conducted a prospective cohort study to explore this complex association.

Methods

A total of 8,077 government employees without HTN were recruited through cluster sampling between 2018 and 2019 in Hunan Province, China. At baseline, information regarding sociodemographic characteristics, LEs, and behavioral factors was collected. After the 1-year follow-up, the participants were revisited to obtain the HTN diagnosis. Crude and adjusted Poisson regression models were constructed to calculate the incidence rate ratios (IRRs) and 95% confidence intervals (CIs). Cubic regression spline models were used to visualize the trends between LEs and HTN IRRs. Interactive and subgroup analyses were also performed.

Results

The 1-year HTN incidence rate among government employees in Hunan province was 4.30% (95% CI: 3.86-4.74%). LEs were associated with a higher HTN risk (IRR, 1.02; 95% CI, 1.00-1.04). When calculating positive and negative LEs scores separately, only the latter was a risk factor for HTN incidence (IRR, 1.04; 95% CI, 1.03-1.06); conversely, positive LEs reduced the risk (IRR, 0.90; 95% CI, 0.85-0.96). Compared with patients in the lowest quartile of LEs score, those in quartiles two (IRR, 1.28; 95% CI, 0.96-1.71), three (IRR, 1.43; 95% CI, 1.04-1.96), and four (IRR, 1.73; 95% CI, 1.26-2.37) were at progressively higher risk. In restricted spline curves, a non-linear association was noted between LEs and HTN risk. Regarding the subcategories of LEs, work-related LEs, personal LEs, and all subcategories of negative LEs were associated with an increased risk of HTN. However, among positive LEs, only the family-related cases were associated with a lower risk of HTN.

Conclusion

LEs had a non-linear association with an increased risk of HTN. Negative LEs were risk factors for HTN incidence, whereas positive LEs reduced the risk of HTN. Thus, the importance of LEs should be highlighted in the development of HTN prevention strategies and initiatives.

Processed Food and Atopic Dermatitis: A Pooled Analysis of Three Cross-Sectional Studies in Chinese Adults

Objective: The effect of processed foods on atopic dermatitis (AD) in adults is unclear. This study was to evaluate the association between processed foods and AD in the Chinese adult population.

Design: This study included three population-based cross-sectional studies using cluster sampling by villages, institutions, or factories. Participants underwent dermatological examinations by certificated dermatologists and a food frequency questionnaire survey. A spot urine sample was collected to estimate the daily sodium intake. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were presented as the effect size.

Setting: Shiyan city of Hubei province, and Huayuan, Shimen, Hengyang, Zhuzhou, and Changsha of Hunan province.

Participants: Automobile manufacture workers from Shiyan of Hubei province, and rural residents and civil servants from Hunan.

Results: A total of 15,062 participants, including 3,781 rural residents, 5,111 civil servants, and 6,170 workers, completed all evaluations. Compared to those hardly consumed pickles, consumption of pickles 1–3 times per week was significantly associated with AD (aOR: 1.35; 95% CI: 1.06–1.70). The intake of processed meats 1–3 times per month (aOR: 1.29; 95% CI: 1.05–1.58) and 1–3 times per week (aOR: 1.44; 95% CI: 1.11–1.87) were associated with AD dose-dependently when compared with those who rarely ate processed meats. Compared with non-consumers, the consumption of any processed foods 1–3 times per week (aOR: 1.39; 95% CI: 1.08–1.80) and ≥4 times per week (aOR: 1.41; 95% CI: 1.05–1.89) showed increased risks of AD. A positive association of estimated sodium intake with AD was also observed.

Conclusion: Intake of processed foods is associated with AD in Chinese adults.

Prevalence of metabolic syndrome, its risk factors and associated lifestyles in Myanmar adult people: A community based cross-sectional study

OBJECTIVES

Metabolic syndrome (MetS) is the constellation of cardio-metabolic risk factors, and it can illustrate the coming burden of cardiovascular diseases and diabetes mellitus. Myanmar faces larger pressure from cardio-metabolic diseases and there is no existing data to understand the magnitude of MetS in adult population. This study aimed to investigate the extent of existing people with MetS in the community and to know the related lifestyle factors to MetS.

METHODS

A community based cross-sectional study was performed in convenient sample of 302 Myanmar adult people. Prevalence of MetS and associated risk factors were identified by collecting sociodemographic information, anthropometric measurements, and blood investigation of glucose and lipid profiles. Logistic regression analysis was performed for developing statistical models to estimate the odd ratios (OR) and confidence intervals (CI).

RESULTS

Prevalence of MetS is 29.1%, and there is no significant difference between male and female prevalence. Abdominal obesity is the highest component of MetS (OR: 28.37, CI: 12.41-64.85, p < 0.001) especially for female (OR: 44.52, CI: 17.19-115.31, p < 0.001), and hypertriglyceridemia (OR: 11.05, CI: 6.20-19.66, p < 0.001) is the commonest in male. Age is the constant risk for developing MetS (OR: 4.06, CI: 1.91-8.64, p < 0.001) whereas the practice of midday nap is the behavior related to increased occurrence of MetS (OR: 1.97, CI: 1.16-3.38, p < 0.05). Dietary pattern, smoking status, drinking alcoholic beverages and physical activity involvement do not impact on the development of MetS. Education, occupation, income and other sociodemographic factors do not produce significant effect on cardio-metabolic status. Obesity, diabetes, and hypertensive conditions of community residents are also explored.

CONCLUSIONS

Modifiable pathophysiological conditions such as abdominal obesity, and obesity play a vital role in preventing MetS before it occurs while unmodifiable risk factor such as getting older and female sex are not as much important as changeable lifestyle habits.

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.

Sociodemographic disparity in health-related behaviours and dietary habits among public workers in China: a cross-sectional study

OBJECTIVE

We aimed to estimate the distribution of health-related behaviours and dietary habits by sociodemographics among public workers in China.

DESIGN

Cross-sectional study.

SETTING

A representative sample was obtained from 10 government-run institutions in Hunan province of China.

PARTICIPANTS

A total of 5029 public workers were included in this study.

PRIMARY AND SECONDARY OUTCOME MEASURES

Prevalence on their sociodemographic characteristics, health-related behaviours and dietary habits. Socioeconomic status (SES) scores were calculated by multiplying ordinal numerical values assigned to consecutive categories of education level and annual household income. Multivariate logistic regression analysis and categorical principal component analysis were used to estimate differences in health-related behaviours and dietary habits by sociodemographics.

RESULTS

The distribution of health-related behaviours and dietary habits was varied by sociodemographic groups. Middle-aged groups (41-60 years) were more likely to smoke (for men, 34.5%), use alcohol (for men, 22.5%), and have short sleep duration (for men, 36.3%; for women, 39.6%). Young participants (≤30 years) were more likely to have multiple unhealthy behaviours and dietary habits. Those in low-SES have a significant higher rate of smoking (OR_adj=1.46, 95% CI: 1.15 to 1.85) and leisure-time physical inactivity (OR_adj=1.18, 95% CI: 1.02 to 1.37), but a lower rate of late sleeping (OR_adj=0.69, 95% CI: 0.57 to 0.83) than those in high-SES. Notably, older men (≥51 years) with low-SES preferred the 'smoked and pickled foods and dessert' and 'fish and nut' pattern. In high-SES groups, 41-50 year old people preferred the 'traditional foods' and 'cereals and dairy product' pattern. No difference in dietary patterns by sociodemographics was found among women (p<0.05).

CONCLUSIONS

Our findings of the disparity distribution of health-related behaviours and dietary habits by specific gender, age and SES among Chinese public workers have important policy implications for developing targeted health interventions to facilitate health-related behaviours and dietary habits in this population.

Association of daytime napping in relation to risk of diabetes: evidence from a prospective study in Zhejiang, China

BACKGROUND

Diabetes was a major risk factor for numerous chronic diseases. However, the associations between daytime napping and diabetes in the existing literature is still inconsistent.

METHODS

The analysis included 53,916 participants aged 30-79 years of the China Kadoorie Biobank prospective study from Tongxiang. Incident diabetes were identified through linkage with incident diabetes surveillance systems, health insurance system, and death registries. Cox regressions were used to estimate the associations of daytime napping with diabetes.

RESULTS

5.11% of participants reported habitual daytime napping. During 488,233 person-years (median 9.4 years) of follow-up, 3333 incident diabetes, including 1249 males and 2084 females, were documented. After adjusting for socio-demographic status, behavioral lifestyle, BMI, waist circumference and snoring, as comparison with those without daytime napping, the hazard ratios for risk of diabetes were 1.39 (95% CI 1.21-1.59). The corresponding figures for males and females were 1.45 (95% CI 1.20-1.74) and 1.30 (95% CI 1.05-1.59), respectively. The corresponding figures for postmenopausal and premenopausal females were 1.41 (95% CI 1.08-1.80) and 1.13 (95% CI 0.78-1.59), respectively.

CONCLUSIONS

Habitual daytime napping is positively associated with risk of diabetes in adults, except premenopausal females.