Interaction between physical activity and sleep duration in relation to insulin resistance among non-diabetic Chinese adults

Individual and interaction effects of monounsaturated fatty acids on their associations with hypertension in Chinese residents

Currently, associations between dietary intakes of individual monounsaturated fatty acids (MUFAs) and hypertension were not well disclosed, and the interaction effects of MUFAs on their associations with hypertension were unknown. Obesity was correlated with both MUFAs and hypertension, while if anthropometric obesity indices performed mediating roles in associations between MUFAs and hypertension remained underdetermined. In our study, 8509 Chinese adults investigated from 2004 to 2011 were included. Dietary information collection and physical examinations were performed at baseline and each timepoint of follow-up. As we found, inverse associations of MUFA17, MUFA18 and MUFA20 with hypertension were statistically significant after adjustments, hazard ratios (HRs) were 0.87, 0.90 and 0.91, respectively. MUFA15 was positively associated with hypertension, with an HR of 1.07 (95% confidence interval: 1.01, 1.12). By performing principal component analysis (PCA) to estimate the joint effects of MUFAs on hypertension, the PCA score of MUFAs was only inversely associated with blood pressure. No joint effect was observed in g-computation analyses. Both linear and nonlinear interactions of MUFAs on their associations with hypertension were estimated using restricted cubic spline analysis. The association between MUFA15 and hypertension was interacted by MUFA17, and the association between MUFA20 and hypertension was interacted by MUFA18. The mediation effects of body mass index and waist circumference were found on associations of hypertension with MUFA15, MUFA17 and MUFA20. Our findings suggested that associations with hypertension were different among individual MUFAs, and mutual interactions existed, implying that the utility of individual MUFAs might be recommended for estimating relationships between MUFAs and diseases. Moreover, fat accumulation might potentially underlie associations between MUFAs and hypertension.

Study on the Impact of Dietary Patterns on Cardiovascular Metabolic Comorbidities among Adults

Background

The prevalence of cardiovascular metabolic comorbidities (CMM) among adults is relatively high, imposing a heavy burden on individuals, families, and society. Dietary patterns play a significant role in the occurrence and development of CMM. This study aimed to identify the combined types of CMM in adult populations and investigate the impact of dietary patterns on CMM.

Methods

Participants in this study were from the sixth wave of the China Health and Nutrition Survey (CHNS). Dietary intake was assessed using a three-day 24-hour dietary recall method among 4,963 participants. Latent profile analysis was used to determine dietary pattern types. Two-step cluster analysis was performed to identify the combined types of CMM based on the participants' conditions of hyperuricemia, dyslipidemia, diabetes, renal dysfunction, hypertension, and stroke. Logistic regression analysis with robust standard errors was used to determine the impact of dietary patterns on CMM.

Results

Participants were clustered into three dietary patterns (Pattern 1 to 3) and five CMM types (Class I to V). Class I combined six diseases, with a low proportion of diabetes. Class II also combined six diseases but with a high proportion of diabetes. Class III combined four diseases, with a high proportion of hypertension. Class IV combined three diseases, with the highest proportions of hyperuricemia, diabetes, and renal dysfunction. Class V combined two diseases, with high proportions of dyslipidemia and renal dysfunction. Patients with Class III CMM had a significantly higher average age than the other four classes (P ≤ 0.05). Compared to those with isolated dyslipidemia, individuals with a low-grain, high-fruit, milk, and egg (LCHFM) dietary pattern had a higher risk of developing dyslipidemia combined with renal dysfunction (Class V CMM) with an odds ratio of 2.001 (95% CI 1.011-3.960, P≤ 0.05).

Conclusion

For individuals with isolated dyslipidemia, avoiding a low-grain, high-fruit, milk, and egg (LCHFM) dietary pattern may help reduce the risk of developing dyslipidemia combined with renal dysfunction (Class V CMM).

Independent and joint association of physical activity and adequate weekday sleep duration with metabolic dysfunction-associated steatotic liver disease

BACKGROUND

The independent and joint association of physical activity (PA) and weekday sleep duration with metabolic dysfunction-associated steatotic liver disease (MASLD) remain unclear.

AIMS

We intended to explore this association in the United States.

METHODS

This cross-sectional study recruited 4974 individuals from the National Health and Nutrition Examination Survey between 2017 and 2018. Information regarding PA and weekday sleep duration was obtained through questionnaires. Metabolic associated fatty liver disease (MAFLD) was diagnosed by transient elastography based on the consensus definitions. Multivariable logistic regression models were employed to investigate the independent and joint association of PA and weekday sleep duration with MAFLD.

RESULTS

Of the 4974 subjects, engaging in active PA or sustaining adequate sleep duration was associated with decreased the odds of MAFLD (p < 0.05). Specifically, active leisure-time PA was linked to lower 37 % odds of MAFLD (OR, 0.63; 95 % CI, 0.55-0.73). Individuals who had one to twice times (150-299 min/week) or more than twice (≥300 min/week) the recommended amount of leisure-time PA by PA Guidelines had 19 % (OR, 0.81; 95 % CI, 0.67-0.99) and 45 % (OR, 0.55; 95 % CI, 0.47-0.65) lower odds of MAFLD, respectively (P for trend <0.001). Individuals with adequate weekday sleep duration was associated with 24 % lower odds of MAFLD (OR, 0.76;95 % CI,0.67-0.88). Notably, active PA combined with adequate weekday sleep duration significantly decreased the odds ratios for MAFLD by 35 % (OR: 0.65, 95 % CI, 0.52-0.80). However, in individuals with significant alcohol use, the joint effect of total PA and weekday sleep duration on MAFLD was not statistically significant.

CONCLUSIONS

Both active PA and adequate weekday sleep duration were inversely associated with the risk of MASLD independently, while combining them could further lower the risk of MASLD.

Exercise intervention in middle-aged and elderly individuals with insomnia improves sleep and restores connectivity in the motor network

Exercise is a potential treatment to improve sleep quality in middle-aged and elderly individuals. Understanding exercise-induced changes in functional plasticity of brain circuits that underlie improvements in sleep among middle-aged and older adults can inform treatment of sleep problems. The aim of the study is to identify the effects of a 12-week exercise program on sleep quality and brain functional connectivity in middle-aged and older adults with insomnia. The trial was registered with Chinese Clinical Trial Register (ChiCTR2000033652). We recruited 84 healthy sleepers and 85 individuals with insomnia. Participants with insomnia were assigned to receive either a 12-week exercise intervention or were placed in a 12-week waitlist control condition. Thirty-seven middle-aged and older adults in the exercise group and 30 in the waitlist group completed both baseline and week 12 assessments. We found that middle-aged and older adults with insomnia showed significantly worse sleep quality than healthy sleepers. At the brain circuit level, insomnia patients showed decreased connectivity in the widespread motor network. After exercise intervention, self-reported sleep was increased in the exercise group (P < 0.001) compared to that in the waitlist group. We also found increased functional connectivity of the motor network with the cerebellum in the exercise group (P < 0.001). Moreover, we observed significant correlations between improvement in subjective sleep indices and connectivity changes within the motor network. We highlight exercise-induced improvement in sleep quality and functional plasticity of the aging brain.

Association of accelerometer-measured sleep duration and different intensities of physical activity with incident type 2 diabetes in a population-based cohort study

PURPOSE

The aim of the current study was to investigate the association of accelerometer-measured sleep duration and different intensities of physical activity (PA) with the risk of incident type 2 diabetes in a population-based prospective cohort study.

METHODS

Altogether, 88,000 participants (mean age = 62.2 ± 7.9 years, mean ± SD) were included from the UK Biobank. Sleep duration (short: <6 h/day; normal: 6-8 h/day; long: >8 h/day) and PA of different intensities were measured using a wrist-worn accelerometer over a 7-day period between 2013 and 2015. PA was classified according to the median or World Health Organization-recommendation: total volume of PA (high, low), moderate-to-vigorous PA (MVPA) (recommended, not recommended), and light-intensity PA (high, low). Incidence of type 2 diabetes was ascertained using hospital records or death registries.

RESULTS

During a median follow-up of 7.0 years, 1615 incident type 2 diabetes cases were documented. Compared with normal sleep duration, short (hazard ratio (HR) = 1.21, 95% confidence interval (95%CI): 1.03-1.41) but not long sleep duration (HR = 1.01, 95%CI: 0.89-1.15) was associated with excessive type 2 diabetes risk. This increased risk among short sleepers seems to be protected against by PA. Compared with normal sleepers with high or recommended PA, short sleepers with low volume of PA (HR = 1.81, 95%CI: 1.46-2.25), not recommended (below the World Health Organization-recommended level of) MVPA (HR = 1.92, 95%CI: 1.55-2.36), or low light-intensity PA (HR = 1.49, 95%CI: 1.13-1.90) had a higher risk of type 2 diabetes, while short sleepers with a high volume of PA (HR = 1.14, 95%CI: 0.88-1.49), recommended MVPA (HR = 1.02, 95%CI: 0.71-1.48), or high light-intensity PA (HR = 1.14, 95%CI: 0.92-1.41) did not.

CONCLUSION

Accelerometer-measured short but not long sleep duration was associated with a higher risk of incident type 2 diabetes. A higher level of PA, regardless of intensity, potentially ameliorates this excessive risk.

Analysis of different plant- and animal-based dietary patterns and their relationship with serum uric acid levels in Chinese adults

BACKGROUND

Dietary patterns play an important role in regulating serum uric acid levels in the body, but evidence for the association between different kinds of plant-based and animal-based dietary patterns and individual serum uric acid levels is scarce and inconsistent.

METHODS

We analyzed data from the sixth wave of the China Health and Nutrition Survey. The plant-based diet of 7,806 participants was determined using three consecutive 24-hour dietary recalls, and latent profile analysis was used to identify dietary patterns among participants. Serum uric acid levels were analyzed using the enzymatic colorimetric method. The association between intakes of different types of dietary pattern and individual serum uric acid levels was analyzed using linear regression analysis, after adjusting for confounding variables.

RESULTS

We identified three types of plant-based dietary patterns, namely, low tuber starches and vegetable plant-based diet (LTVP), high cereal, tuber starches and vegetable plant-based diet (HCTVP), and high legume and fruit plant-based diet (HLFP). We also identified three types of animal-based dietary patterns, namely, high milk and egg animal-based diet (HMiEA), low egg and fish animal-based diet, and high meat and fish animal-based diet (HMeFA). Significant coefficients for participant serum uric acid levels were observed for the HCTVP diet (β = -0.022, P = 0.031) and HMeFA diet (β = 0.061, P < 0.001). The median intake of foods in the HCTVP diet was as follows: cereals and cereal products, 444.83 g/d; tubers and starch products, 166.67 g/d; dried legumes and legume products, 8.33 g/d; vegetables and vegetable products, 333.33 g/d; and fruits and fruit products, 0 g/d. The median intake of foods in the HMeFA diet was as follows: meat and meat products, 73.33 g/d; poultry and poultry products, 0 g/d; milk and milk products, 0 g/d; eggs and egg products, 26.67 g/d; and fish, shellfish, and mollusks, 180.00 g/d.

CONCLUSION

We showed that individual serum uric acid levels (1) might decrease under the plant-based HCTVP diet, (2) might increase under the animal-based HMeFA diet, (3) might not decrease under the plant-based HLFP diet, and (4) might not increase under the animal-based HMiEA diet. Further studies are needed to confirm these associations.

Dietary intakes of methionine, threonine, lysine, arginine and histidine increased risk of type 2 diabetes in Chinese population: does the mediation effect of obesity exist?

BACKGROUND

Published studies have shown positive associations of branched chain and aromatic amino acids with type 2 diabetes mellitus (T2DM), and the findings remain consistent. However, the associations of other essential and semi-essential amino acids, i.e., methionine (Met), threonine (Thr), lysine (Lys), arginine (Arg) and histidine (His), with T2DM remain unknown. Obesity is an important independent risk factor for T2DM, and excessive amino acids can convert into glucose and lipids, which might underlie the associations of amino acids with obesity. Therefore, we aimed to estimate the associations between dietary intakes of these 5 amino acids and T2DM risk, as well as the mediation effects of obesity on these associations, in a Chinese population.

METHODS

A total of 10,920 participants (57,293 person-years) were included, and dietary intakes of 5 amino acids were investigated using 24-h dietary recalls. Anthropometric obesity indices were measured at both baseline and the follow-up endpoints. Associations of amino acids with T2DM were estimated using COX regression models, hazard ratios (HRs) and 95% confidence intervals (95% CIs) were shown. The mediation effects of obesity indices were analyzed, and the proportion of the mediation effect was estimated.

RESULTS

Higher intakes of the 5 amino acids were associated with increasing T2DM risk, while significant HRs were only shown in men after adjustments. No interaction by gender was found. Regression analyses using quintiles of amino acids intakes showed that T2DM risk was positively associated with amino acids intakes only when comparing participants with the highest intake levels of amino acids to those with the lowest intake levels. Adjusted correlation coefficients between amino acid intakes and obesity indices measured at follow-up endpoints were significantly positive. Mediation analyses showed that mediation effects of obesity indices existed on associations between amino acids intakes and T2DM risk, and the mediation effect of waist circumference remained strongest for each amino acid.

CONCLUSIONS

We found positive associations of dietary intakes of Met, Thr, Lys, Arg and His with increasing T2DM risk in general Chinese residents, on which the mediation effect of obesity existed. These findings could be helpful for developing more constructive guidance in the primary prevention of T2DM based on dietary interventions.

The role of insufficient sleep and circadian misalignment in obesity

Traditional risk factors for obesity and the metabolic syndrome, such as excess energy intake and lack of physical activity, cannot fully explain the high prevalence of these conditions. Insufficient sleep and circadian misalignment predispose individuals to poor metabolic health and promote weight gain and have received increased research attention in the past 10 years. Insufficient sleep is defined as sleeping less than recommended for health benefits, whereas circadian misalignment is defined as wakefulness and food intake occurring when the internal circadian system is promoting sleep. This Review discusses the impact of insufficient sleep and circadian misalignment in humans on appetite hormones (focusing on ghrelin, leptin and peptide-YY), energy expenditure, food intake and choice, and risk of obesity. Some potential strategies to reduce the adverse effects of sleep disruption on metabolic health are provided and future research priorities are highlighted. Millions of individuals worldwide do not obtain sufficient sleep for healthy metabolic functions. Furthermore, modern working patterns, lifestyles and technologies are often not conducive to adequate sleep at times when the internal physiological clock is promoting it (for example, late-night screen time, shift work and nocturnal social activities). Efforts are needed to highlight the importance of optimal sleep and circadian health in the maintenance of metabolic health and body weight regulation.

Domestic Physical Activity and New-Onset Hypertension: A Nationwide Cohort Study in China

BACKGROUND

The relation of domestic physical activity with hypertension remains uncertain. We aimed to evaluate the prospective relation of domestic physical activity and new-onset hypertension among Chinese males and females.

METHODS

A total of 9254 adults who were free of hypertension at baseline were enrolled from the China Health and Nutrition Survey. Data on domestic physical activity were obtained by using self-reported questionnaires, and calculated as metabolic equivalent task (MET)-hours/week. Metabolic equivalent task-hours/week may account for both intensity and time spent on activities. The study outcome was new-onset hypertension, defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg or diagnosed by physician or under antihypertensive treatment during the follow-up.

RESULTS

A total of 2892 participants developed hypertension during 81996 person-years of follow-up. Overall, there were reversed J-shaped associations between the domestic physical activity and new-onset hypertension in both males and females (both P values for nonlinearity < .001). Consistently, when domestic physical activity was assessed as categories (<10, 10 -< 20, 20 -< 30, 30 -< 40, 40 -< 50, 50 -< 60, 60 -<70, 70 -< 80, 80 -< 90, 90 -< 100, ≥100 MET-hours/week), compared with those with domestic physical activity < 10 MET-hours/week, the lower and similar risks of new-onset hypertension were found in participants with domestic physical activity 30 -< 90 MET-hours/week in both males and females.

CONCLUSIONS

Moderate domestic physical activity was associated with a lower risk of new-onset hypertension among both males and females.

Preliminary evidence of insulin resistance in young adults with impaired sleep

Objective: Impaired sleep is associated with insulin resistance (IR), a precursor to type 2 diabetes mellitus (T2DM), but is poorly understood in young adults. This cross-sectional study examined sleep characteristics, risk factors for T2DM, and IR in college students. Participants: Thirty-two college students (18-25 years) with either short sleep or poor quality sleep were assessed. Methods: Participants completed self-report measures of sleep and T2DM risk factors. One week of objective sleep was measured with wrist actigraphy. IR was calculated from fasting serum glucose and insulin concentrations. Results: The sample slept on average 6.6 hours/night, and over half had IR. Of those with IR, 44.4% had normal body mass index (BMI), 72% had normal fasting glucose concentrations, and all but one had T2DM risk test score indicating they were not at risk. Conclusions: IR was found in over half of participants; however, many typical T2DM risk factors were not present in those with IR.

Transportation physical activity and new-onset hypertension: A nationwide cohort study in China

The association between transportation physical activity (PA) and the risk of hypertension remains uncertain. We aimed to evaluated the prospective relation of transportation PA and new-onset hypertension among Chinese adults. A total of 9350 adults who were free of hypertension at baseline were enrolled from the China Health and Nutrition Survey (CHNS). Data on transportation PA were obtained by using self-reported questionnaires, and calculated as metabolic equivalent task (MET)-minutes/week. MET-minutes/week may account for both intensity and time spent on activities. The study outcome was new-onset hypertension, defined as systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg or diagnosed by physician or under antihypertensive treatment during the follow-up. During a median of 8.0 years (82,410 person-years) of follow-up, a total of 2949 participants developed hypertension. Overall, there was a U-shaped association between transportation PA and new-onset hypertension (P values for nonlinearity <0.001). Accordingly, compared with those with moderate transportation PA (213-<394 MET-minutes/week, the second quartile), significantly higher risks of new-onset hypertension were observed not only in participants with transportation PA < 213 MET-minutes/week (the first quartile) (HR, 1.29; 95%CI: 1.15-1.44), but in those with transportation PA ≥ 394 MET-minutes/ week (the 3-4 quartiles) (HR, 1.15; 95%CI: 1.04-1.27). Similar U-shaped correlations were found for various types of transportation PA (walking, bicycling, and motorized PA) and new-onset hypertension. In summary, moderate transportation PA is associated with a lower risk of new-onset hypertension among Chinese adults.

Association between Excessive Dietary Branched-Chain Amino Acids Intake and Hypertension Risk in Chinese Population

The dietary intake of branched-chain amino acids (BCAAs) has been reported to be associated with both elevated blood pressure (BP) and hypertension risk, while published findings were inconsistent, and the causality has never been well disclosed. We performed this prospective study aiming to find out the relationship between dietary BCAAs intake and hypertension risk in the Chinese population. A total of 8491 participants (40,285 person-years) were selected. The levels of dietary BCAAs intake were estimated using the 24-h Food Frequency Questionnaire. Associations of both BP values and hypertension risk with per standard deviation increase of BCAAs were estimated using linear and COX regression analysis, respectively. The hazard ratios and 95% confidence interval were given. Restricted cubic spline analysis (RCS) was used to estimate the nonlinearity. Both systolic and diastolic BP values at the end points of follow-up were positively associated with dietary BCAAs intake. Positive associations between BCAAs intake and hypertension risk were shown in both men and women. By performing a RCS analysis, the nonlinear relationship between BCAAs intake and hypertension was shown. As the intake levels of Ile, Leu, and Val, respectively, exceeded 2.49 g/day, 4.91 g/day, and 2.88 g/day in men (2.16 g/day, 3.84 g/day, and 2.56 g/day in women), the hypertension risk increased. Our findings could provide some concrete evidence in the primary prevention of hypertension based on dietary interventions.

The Association between Physical Activity and Cognitive Function: Data from the China Health and Nutrition Survey

Background

Decreased cognitive function is a common problem in the old adults, which has high risk of progression to Alzheimer's diseases (AD) and other dementias. This study was aimed at finding out the association between physical activity and cognitive function.

Methods

In total, 1514 participants with the age ≥ 55 years old registered in the China Health and Nutrition Survey (CHNS) database were selected in this study. The association between physical activity and cognitive function was analyzed via the generalized additive model. The association between the variables and the cognitive function score was expressed as β coefficient with 95% confidence intervals (CIs).

Results

After adjusting age, ethnicity, stratum, marital status, education, memory status, and memory changes, the cognitive function score was increased by 0.011 points for every 1-point increase in domestic score (β = 0.011, P = 0.043). Subgroup analysis indicated that in the female group, for every 1-point increase in the domestic score, the cognitive function score increased by 0.019 points (β = 0.019, P = 0.017). In people with good memory status, each 1-point increase in domestic score increased the cognitive function score of 0.020 points (β = 0.020, P = 0.017).

Conclusions

The decreased cognitive function was correlated with decreased domestic physical activity. The increased domestic physical activity was associated with an increased cognitive function in females and people with good memory status. The findings might offer a reference for deep understanding of the association between physical activity and cognitive function.

Specific Types of Physical Exercises, Dietary Preferences, and Obesity Patterns With the Incidence of Hypertension: A 26-years Cohort Study

Objectives: To examine the associations of specific types of physical exercises, dietary preferences, and obesity patterns with incident hypertension.

Methods: In this cohort study, obesity patterns were defined using general and abdominal obesity as G-/A-, G+/A- or G-/A+, and G+/A+. The type of physical exercises and dietary preferences were collected using a validated questionnaire. Participants with systemic blood pressure/diastolic blood pressure ≥140 mmHg/90 mmHg, use of antihypertensive medications, or a self-reported diagnosis were identified as hypertension.

Results: There were 10,713 participants in this study. Martial arts, gymnastics, and ping pong could decrease the risk of hypertension (HR: 0.792, 0.884, and 0.855; and 95% CI: 0.743–0.845, 0.825–0.948, and 0.767–0.953, respectively). However, TV or computer usage, and consumption of fast food, soft/sugared drinks, and salty snack food could increase incident hypertension (HR: 1.418, 1.381, 1.233, and 1.225; and 95% CI: 1.315–1.529, 1.269–1.504, 1.157–1.314, and 1.139–1.316, respectively). Obese subjects had an increased risk of hypertension.

Conclusion: The type of physical exercises, dietary preferences, and obesity patterns were associated with incident hypertension. More attention should be paid to these lifestyles to benefit health outcomes.

Joint effects of self-reported sleep and modifiable physical activity on risk of dyslipidaemia in women aged 45-55 years: a cross-sectional study

OBJECTIVES

Modifiable physical activity (PA) plays an important role in dyslipidaemia risk in middle-aged women with sleep problems, especially perimenopausal women. We aimed to explore the joint effects of sleep and PA on the risk of dyslipidaemia in women aged 45-55 years, and the extent to which PA moderated the effect of sleep on the risk of dyslipidaemia.

DESIGN

A cross-sectional study.

SETTING

This study was based on the survey of Chronic Disease and Nutrition Monitoring in Adults in Inner Mongolia in 2015.

PARTICIPANTS

721 women aged 45-55 years were included.

OUTCOME MEASUREMENT

PA was measured by the Global Physical Activity Questionnaire. Sleep was measured by questionnaire formulated by the Chinese Center for Disease Control and Prevention. Multivariate logistic regression analyses were performed to determine the joint effects of sleep and PA on dyslipidaemia risk. OR and 95% CI were reported.

RESULTS

Among all participants, 60.6% had sleep problems, 29.0% had low PA and 41.1% had dyslipidaemia. Women with sleep problems had higher dyslipidaemia risk than women without sleep problems, irrespective of low, moderate or high PA, with OR (95% CI) of 4.24 (2.40 to 7.49), 3.14 (1.80 to 5.49) and 2.04 (1.20 to 3.48), respectively. PA could not completely attenuate the negative association between sleep and dyslipidaemia risk. With PA increased from low to high, the OR of dyslipidaemia decreased by 2.20. Women with sleep problems and low PA had higher risks of high total cholesterol, high triglyceride, low high-density lipoprotein cholesterol and high low-density lipoprotein cholesterol than women without sleep problems and high PA, with OR (95% CI) of 2.51 (1.18 to 5.35), 2.42 (1.23 to 4.74), 2.88 (1.44 to 5.74) and 2.52 (1.12 to 5.70), respectively.

CONCLUSIONS

Among women aged 45-55 years, the joint effects of self-reported sleep and PA on dyslipidaemia risk were more marked for sleep than for PA. Modifiable PA is a widely accessible and effective intervention to reduce the dyslipidaemia risk in women with sleep problems, particularly among perimenopausal women.

Occupational and domestic physical activity and diabetes risk in adults: Results from a long-term follow-up cohort

BACKGROUND

Physical activity (PA) has been associated with decreased incidence of diabetes. However, few studies have evaluated the influence of occupational and domestic PA on the risk of diabetes with a long-term follow-up. We aimed to examine the association between occupational and domestic PA and the risk of diabetes in a long-term prospective cohort of Chinese adults.

METHODS

A total of 10,343 adults who were followed up in the China Health and Nutrition Survey from 1997 to 2015 were included in our analysis. Occupational and domestical PA were collected with detailed seven-day data and were converted into metabolic equivalents values. Total PA included occupational, domestic, transportation, and leisure time PA. Diabetes cases were identified by self-reported doctor/health professional diagnosis of diabetes, fasting blood glucose ≥7.0 mmol/L, and glycosylated hemoglobin (HbA1c) ≥6.5%. Cox proportional hazards models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI).

RESULTS

During up to 18 years of follow-up (median 10 years), there were 575 diabetes cases documented. Occupational PA accounted for the majority of total PA (68%) in Chinese population, followed by domestic PA (25%). With adjustments for possible covariates, the highest quartiles of total PA (HR, 0.728 [95% CI, 0.570-0.929]) and occupational PA (HR, 0.765 [95% CI, 0.596-0.982]) were significantly associated with a lower risk of diabetes compared with lowest quartiles. The association between domestic PA and the risk of diabetes was insignificant (P >0.05).

CONCLUSION

Higher levels of occupational PA were associated with a decreased risk of diabetes risk in the Chinese population. Domestic PA was not associated with the incidence of diabetes.

The Interaction Between Self-Reported Sleep Duration and Physical Activity on Peripheral Artery Disease in Chinese Adults: A Cross-Sectional Analysis in the Tianning Cohort Study

Purpose

Sleep duration was associated with large artery atherosclerosis, but its association with atherosclerosis in lower extremity arteries was not well studied. Together with sleep, physical activity constitutes main component of our daily life and influences sleep. Here, we aimed to examine the independent and joint associations of sleep duration and physical activity with peripheral artery disease (PAD) in Chinese adults.

Patients and Methods

In Tianning cohort, night-time sleep duration and physical activity were assessed by the Pittsburgh Sleep Quality Index and the Global Physical Activity Questionnaire, respectively, for 5130 participants (51.0±15.6 years, 58.7% female). PAD was defined as ankle-brachial index (ABI) <0.9. General linear, and logistic regression models were used to assess the associations of sleep duration and physical activity with PAD. The biological interaction between sleep duration and physical activity on PAD was examined using additive model.

Results

Compared to participants sleeping 6-8.9 h, those sleeping ≥9 h had a 0.02 lower ABI (β=-0.02, P=0.007) and 38% higher odds of PAD (OR=1.38, P=0.035). Compared to physically active participants sleeping 6-8.9 h, among ≥9 h group, physically inactive individuals had significantly increased odds of PAD (OR=2.40, P<0.001), whereas physically active individuals did not (OR=1.15, P=0.472). On additive scale, attributable proportion due to interaction (0.40, 95% CI: 0.07, 0.73) indicated a significant interaction between sleep duration and physical activity on PAD.

Conclusion

Being physically active may attenuate the detrimental association between prolonged sleep duration and PAD. Moreover, we found a significant interaction between prolonged sleep duration and physical inactivity in the prevalence of PAD.

Occupational Physical Activity and New-Onset Hypertension: A Nationwide Cohort Study in China

[Figure: see text].

Influence of occupation type on the association between sleep duration and impaired fasting glucose: results from a Chinese population-based study

OBJECTIVES

Systematic evaluation of the influence of occupation type on the association between sleep-glucose metabolism DESIGN: A cross-sectional study.

SETTING

The Nantong Metabolic Syndrome Study is a Chinese population-based study.

PARTICIPANTS

20 502 participants aged 18-74 years old.

INTERVENTION

No intervention.

PRIMARY AND SECONDARY OUTCOME MEASURES

Impaired fasting glucose (IFG).

RESULTS

A total of 1503 participants (7.33%) with a slightly longer sleep duration had IFG. After being stratified according to occupation, a sleep duration of ≥10 hours daily corresponded to a 1.321-fold risk of IFG (95% CI 1.071 to 1.628, p=0.0092) among moderate and heavy physical workers compared with those with a daily sleep duration of 7-9 hours. There was no significant relationship between sleep and IFG among other types of workers. Moreover, we discovered a gender difference in the influence of occupation on the sleep-IFG. A positive association among moderate and heavy physical men and a negative association among light or sedentary men were established, but not in unemployed men. However, a positive association was evident only in unemployed women; there was no significant association among other occupations.

CONCLUSION

This study highlights the role of occupation in the relationship of sleep-glucose metabolism. A gender difference was found to have been influenced by occupational types on the sleep-metabolic association.

Dietary Diversity and the Risk of Fracture in Adults: A Prospective Study

Nutrition plays an important and modifiable role in bone health. This study aimed to investigate the effect of dietary diversity on the risk of any type of fracture in adults. Data from the China Health and Nutrition Survey collected between waves 1997 and 2015 were used. A total of 10,192 adults aged 40 years and older were included in the analysis. Both dietary diversity score (DDS) based on Chinese dietary guidelines (DDS-CDG) and minimum dietary diversity for women (DDS-MDD-W) were computed. Cox proportional hazards regression models were conducted to determine the association. Stratified analyses were conducted in women by the age of fracture using the case-control study approach. In men, higher scores in both the DDS-CDG (hazard ratio (HR) 0.70, 95% CI 0.56-0.88) and DDS-MDD-W (HR 0.67, 95% CI 0.54-0.82) were associated with decreased risk of fracture, however, the associations were not significant in women (DDS-CDG: HR 0.94, 95% CI 0.79-1.12; DDS-MDD-W: HR 0.93, 95% CI 0.79-1.09). In the stratified analyses, higher DDS-CDG (odds ratio (OR) 0.74, 95% CI 0.58-0.95) and higher DDS-MDD-W (OR 0.76, 95% CI 0.60-0.95) were associated with lower risks of fracture in women aged 40 to 60 years; in women aged over 60 years, no association was observed (DDS-CDG: OR 1.10, 95% CI 0.83-1.46; DDS-MDD-W: OR 1.00, 95% CI 0.79-1.27). In summary, higher dietary diversity was associated with decreased risk of fracture in men and middle-aged women, but not in women aged over 60 years.

Elevated Fat Intake Increases Body Weight and the Risk of Overweight and Obesity among Chinese Adults: 1991-2015 Trends

Studies on fat intake and obesity have been inconclusive. This study examined the associations between dietary fat intake and body weight and the risk of overweight and obesity in China. We used data from 23,859 adults aged 20-60 years who participated in the China Health and Nutrition Survey, an ongoing open-cohort study, from 1991 to 2015. We collected detailed dietary data by conducting three 24-h dietary recalls and weighing foods and condiments in household inventories. We examined the associations between fat intake and body weight, body mass index (BMI), and the risk of overweight and obesity with random-effects linear or logistic regression models for panel data. The Chinese population's fat intake, percentage of energy intake from fat, and prevalence of high-fat diets (energy intake from fat > 30%) increased from 68.5 g per day (g/d), 23.1%, and 22.4%, respectively, in 1991 to 79.3 g/d, 35.6%, and 67.2%, respectively, in 2015. The prevalence of overweight and obesity increased from 12.3% to 37.3% during the same period. Fat intake, percentage of energy intake from fat, and a high-fat diet were positively associated with body weight, BMI, and the risk of overweight and obesity in both sexes (p < 0.001) after adjustment for nonfat energy intake, physical activity, and socioeconomic status. Increased fat intake and high-fat diets were associated with increased body weight, BMI, and risk of overweight and obesity. These findings could have a significant impact on Chinese policies and interventions to control overweight and obesity.

The Visceral Adipose Index in Relation to Incidence of Hypertension in Chinese Adults: China Health and Nutrition Survey (CHNS)

Hypertension is the most crucial single contributor to global burden of disease and mortality, while weight loss as a non-pharmacological strategy is recommended to reduce blood pressure. This study aims to examine the association between visceral adipose index (VAI) and hypertension in Chinese adults. Data were collected from the China Health and Nutrition Survey (CHNS), consisting of 8374 apparently healthy participants aged ≥18 years in the 2009 CHNS for cross-sectional analysis, and 4275 participants at entry from 2009 to 2011 for cohort analysis. Height, weight, waist circumference, blood pressure (BP), and blood lipid were measured. Information of population characteristics, smoking status, alcohol consumption, physical activity, and diet were determined by validated questionnaire. Higher VAI scores were significantly associated with higher BP levels and higher risk of hypertension after adjustment with potential confounders (all p-trend < 0.001). The adjusted hazard ratio of hypertension was 1.526 (95%CI: 1.194, 1.952; p-trend < 0.01) for participants in the highest quartile of VAI scores when compared with those in the lowest quartile after adjustment for age, physical activity, antihypertensive medication, total energy intake, salt intake, and other major lifestyle factors. VAI scores were significantly, longitudinally associated with hypertension development among apparently healthy Chinese adults.

Associations between sleep duration and sleep debt with insulin sensitivity and insulin secretion in the EGIR-RISC Study

AIM

Extremes in sleep duration play an important role in the development of type 2 diabetes. We examined the associations between sleep duration and sleep debt with estimates of insulin sensitivity and insulin secretion.

METHODS

Data were derived from the European multi-centre EGIR-RISC study. Sleep duration and sleep debt were derived from a sleep questionnaire asking about sleeping time during the week and during the weekend. Insulin sensitivity and insulin secretion were estimated from a 2-hour Oral Glucose Tolerance Test, with samples every 30 minutes. Associations between sleep duration and sleep debt with insulin sensitivity and insulin secretion, were analysed by multiple linear regression models corrected for possible confounders.

RESULTS

Sleep data were available in 1002 participants, 46% men, mean age 48 ± 8 years, who had an average sleep duration of 7 ± 1 hours [range 3-14] and an average sleep debt (absolute difference hours sleep weekend days minus weekdays) of 1 ± 1 hour [range 0-8]. With regard to insulin sensitivity, we observed an inverted U-shaped association between sleep duration and the Stumvoll MCR in (mL/kg/min), with a corrected β (95% CI) of 2.05 (0.8; 3.3) and for the quadratic term -0.2 (-0.3; -0.1). Similarly, a U-shaped association between sleep duration and log HOMA-IR in (µU/mL), with a corrected βs of -0.83 (-1.4; -0.24) and 0.06 (0.02; 0.10) for the quadratic term. Confounders showed an attenuating effect on the associations, while BMI mediated 60 to 91% of the association between sleep duration and insulin sensitivity. No significant associations were observed between sleep duration with insulin secretion or between sleep debt with either insulin sensitivity or insulin secretion.

CONCLUSIONS

Short and long sleep duration are associated with a lower insulin sensitivity, suggesting that sleep plays an important role in insulin resistance and may provide the link with development of type 2 diabetes.

The relationship between employment status and insulin resistance in the Korean elderly population

BACKGROUND/AIMS

This study aimed to investigate the relationship between employment status and insulin resistance in the Korean elderly population.

METHODS

The study included 2325 healthy participants (862 men and 1463 women) who did not have diabetes, were 60-74 years old, and participated in the 2007-2010 Korea National Health and Nutrition Examination Survey. Their employment status was categorized as employed or unemployed. The homeostasis model assessment of insulin resistance (HOMA-IR) was used to assess insulin sensitivity. Insulin resistance was defined as values greater than the 75th percentile of the HOMA-IR (> 2.67 in men and > 2.87 in women).

RESULTS

Mean HOMA-IR values were significantly higher for both sexes in the unemployed group than in the employed group. Compared with the unemployed group, the odds ratios (95% confidence intervals) for insulin resistance in the employed group were 0.55 (0.34-0.87) in men and 0.68 (0.47-0.98) in women after adjusting for confounders.

CONCLUSIONS

Being employed was significantly associated with a lower risk of insulin resistance in the Korean elderly population. These findings suggest that insulin sensitivity could be increased by increasing physical activity through occupational activities in the elderly population.

Sex-dependent difference in the association between frequency of spicy food consumption and risk of hypertension in Chinese adults

PURPOSE

The aim of our study was to explore the association between frequency of spicy food consumption and risk of hypertension in Chinese adults.

METHODS

Data were extracted from the 2009 wave of the China Health and Nutrition Survey, consisting of 9273 apparently healthy adults. Height, weight, and blood pressure (BP) were measured and diet was assessed with three consecutive 24-h recalls in combination with a weighed food inventory. Frequency of spicy food consumption and degree of pungency in spicy food consumption were self-reported. Hypertension was defined as systolic BP (SBP) ≥ 140 mmHg and/or diastolic BP (DBP) ≥ 90 mmHg, or having known hypertension. Multilevel mixed-effects models were constructed to estimate changes in SBP and DBP levels as well as risk of hypertension.

RESULTS

Higher frequency of spicy food consumption was significantly associated with lower SBP and DBP levels and lower risk of hypertension in female participants after adjustment for potential confounders (all P trend < 0.05) and cluster effects at different levels (individual, community, and province). Compared with female participants who did not eat spicy food, the adjusted odds ratios of hypertension were 0.740 (95% CI 0.569, 0.963; P = 0.025) in female participants who consumed usually, and 0.760 (95% CI 0.624, 0.925; P = 0.006) in female participants who ate spicy food with moderate pungency. There was no significant association of spicy food consumption with hypertension in male participants.

CONCLUSIONS

Frequency of spicy food consumption was inversely associated with risk of hypertension in female, but not male adults.

Barriers and facilitators to physical activity among urban residents with diabetes in Nepal

INTRODUCTION

Physical activity is an important component of type 2 diabetes management. Physical activity level among general population in Nepal is reported to vary considerably. However, knowledge on physical activity in Nepali diabetics is very limited. Engagement in physical activity could be influenced by perception of barriers against adopting the behavior and benefits of adopting it. This study explores the prevalence of physical activity and factors that promote and hinder the behavior among urban residing diabetic patients from Nepal.

METHODS

A descriptive cross-sectional design was adopted using a simple random sampling of type 2 diabetic patients from two diabetes clinics at Lalitpur and Kaski districts of Nepal. Two hundred and seventy participants were surveyed to obtain information on physical activity using Global Physical Activity Questionnaire. Metabolic equivalent values were calculated and categorized into high, moderate and low levels of physical activity. The information on perceived facilitators and barriers was collected by Exercise Barriers and Benefits Survey scale. Odds ratios and 95% confidence intervals of the measures were estimated using multinomial logistic regression.

RESULTS

The study showed relatively high prevalence of physical activity among the urban Nepali diabetic patients; 52% were moderately active and 28% highly active. Travel and work-related activities were the major contributors. Male participants, educated and those living in extended families were more motivated for physical activity than their counterparts. Physical fitness, strength and flexibility, better sleep at night, social interaction and longevity, were identified as the major facilitators. Family responsibilities, busy schedule and family discouragement were identified as barriers against being physically active.

CONCLUSION

The diabetic patients were mostly moderately physically active. Future research could explore different context-specific ways of remaining physically active, apart from walking and doing household chores. More focus should also be placed on leisure time physical activity as it was found to be low. Interventions could be designed by promoting the facilitators and addressing the barriers of physical activity, which is likely to reduce the healthcare costs of management of diabetic complications.

Markers of Iron Status Are Associated with Risk of Hyperuricemia among Chinese Adults: Nationwide Population-Based Study

Background: Elevated serum uric acid (SUA) involved in iron metabolism, has been increasingly recognized as a risk factor for gout and cardiovascular diseases. The objective of this study was to examine the associations between markers of iron status with risk of hyperuricemia (HU) in Chinese adult population. Methods: Data were extracted from the 2009 wave of the China Health and Nutrition Survey, consisting of 7946 apparently healthy adults. Serum ferritin (SF), transferrin, soluble transferrin receptors (sTfR), hemoglobin (Hb), high-sensitivity C-reactive protein (hs-CRP), and SUA were measured. Diet was assessed with three consecutive 24 h recalls. Demographic characteristics, smoking status, alcohol consumption, and physical activities were investigated using a structured questionnaire. Multilevel mixed-effects models were constructed to estimate the associations of SF, transferrin, sTfR, and Hb with SUA and the risk of HU. Results: The crude prevalence of HU was 16.1%. SF, transferrin, and Hb levels were positively associated with SUA and the risk of HU after adjustment for cluster effects and potential confounders (all p-trend < 0.05). Compared with participants in the lowest quartile of SF, those in the highest quartile had significantly higher SUA concentrations (β = 0.899 mg/dL, 95% confidence interval (CI): 0.788, 1.010; p < 0.001) and higher risk of HU (odds ratio (OR) = 3.086, 95% CI: 2.450, 3.888; p < 0.001). Participants with the highest quartile of transferrin had significantly higher SUA concentrations (β = 0.488 mg/dL, 95% CI: 0.389, 0.587; p < 0.001) and higher risk of HU (OR: 1.900; 95% CI: 1.579, 2.286; p < 0.001) when compared with those with the lowest quartile. In male participants, those in the highest quartile of Hb had significantly higher risk of HU when compared to the reference group (OR: 1.401, 95% CI: 1.104, 1.777; p < 0.01); however, this association was not found in female participants (OR: 1.093; 95% CI: 0.821, 1.455; p = 0.544). Conclusion: SF, transferrin, and Hb levels were positively associated with the risk of HU, and additional studies are needed to confirm the findings, as well as to elucidate their underlying mechanisms.

Association between spicy food consumption and lipid profiles in adults: a nationwide population-based study

CVD remains the leading cause of mortality worldwide, with abnormal lipid metabolism as a major risk factor. The aim of this study was to investigate associations between spicy food consumption and serum lipids in Chinese adults. Data were extracted from the 2009 phase of the China Health and Nutrition Survey, consisting of 6774 apparently healthy Chinese adults aged 18-65 years. The frequency of consumption and degree of pungency of spicy food were self-reported, and regular spicy food consumption was assessed using three consecutive 24-h recalls. Total cholesterol, TAG, LDL-cholesterol and HDL-cholesterol in fasting serum were measured. Multilevel mixed-effects models were constructed to estimate associations between spicy food consumption and serum lipid profiles. The results showed that the frequency and the average amount of spicy food intake were both inversely associated with LDL-cholesterol and LDL-cholesterol:HDL-cholesterol ratio (all P for trend<0·05) after adjustment for potential confounders and cluster effects. HDL-cholesterol in participants who usually consumed spicy food (≥5 times/week) and who consumed spicy food perceived as moderate in pungency were significantly higher than those who did not (both P<0·01). The frequency and the average amount of spicy food intake and the degree of pungency in spicy food were positively associated with TAG (all P for trend<0·05). Spicy food consumption was inversely associated with serum cholesterol and positively associated with serum TAG, and additional studies are needed to confirm the findings as well as to elucidate the potential roles of spicy food consumption in lipid metabolism.

Gender impacts on the correlations between nonalcoholic fatty liver disease and hypertension in a Chinese population aged 45-60 y

No previous study has reported the association between nonalcoholic fatty liver disease (NAFLD) and the risk of hypertension in the Chinese population. Therefore, the aim of this study was to evaluate the relationship between NAFLD and hypertension in a middle-aged Chinese population. The study subject was (a group of) 1006 Chinese adults aged 45-60 y in Shandong Province who participated in the Weifang Nutrition and Health Survey (2014-2015). Hypertension was defined as systolic blood pressure (SBP) ≥140 mmHg or diastolic blood pressure (DBP) ≥ 9 0mmHg. NAFLD was defined as the presence of moderate-severe hepatic steatosis (by B-ultrasonic examination), the absence of excessive alcohol use (>20 g/d in men and 10 g/d in women), no use of steatogenic medications within the past six months, no exposure to hepatotoxins, and no history of bariatric surgery. All anthropometric measurements and biochemical data were collected following standard protocols. Multivariate logistic regression analysis was used to identify the association between NAFLD and hypertension with adjustment of potential confounding variables. Body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), fasting glucose, SBP, DBP, triglycerides (TG), serum uric acid (SUA), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and the prevalence of hypertension and NAFLD were significantly higher in males than in females (p < 0.05). Females had significantly higher levels of total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C). After adjusting for potential confounders, NAFLD was associated with an increased risk of hypertension in both male and female, with odds ratios (ORs) (95% CI) of 2.152 (1.324-3.498) and 2.133 (1.409-3.229), respectively.

CONCLUSIONS

Our findings indicated that NAFLD was significantly associated with the risk of hypertension in males than in females. However, our findings also need to be confirmed in future prospective studies.

ABBREVIATIONS

BMI: body mass index; WC: waist circumference; WHR: waist-hip ratio; SBP: systolic blood pressure; DBP: diastolic blood pressure; FG: fasting glucose; TG: triglycerides; TC: total cholesterol; HDL-C: high-density lipoprotein cholesterol; SUA: serum uric acid; NAFLD: nonalcoholic fatty liver disease; LDL-C: low-density lipoprotein cholesterol; OR: odds ratio; CI: confidence interval; ALT: alanine aminotransferase; AST: aspartate aminotransferase.

Dietary pattern transitions, and the associations with BMI, waist circumference, weight and hypertension in a 7-year follow-up among the older Chinese population: a longitudinal study

BACKGROUND

Few studies explored the effects of nutritional changes on body mass index (BMI), weight (Wt), waist circumference (WC) and hypertension, especially for the older Chinese population.

METHODS

By using China Health and Nutrition Survey 2004-2011 waves, a total of 6348 observations aged ≥ 60 were involved in the study. The number of participants dropped from 2197 in 2004, to 1763 in 2006, 1303 in 2009, and 1085 in 2011. Dietary information was obtained from participants using 24 hour-recall over three consecutive days. Height, Wt, WC, systolic and diastolic blood pressure were also measured in each survey year. The dietary pattern was derived by exploratory factor analysis using principal component analysis methods. Linear Mixed Models were used to investigate associations of dietary patterns with BMI, Wt and WC. Generalized Estimating Equation models were used to assess the associations between dietary patterns and hypertension.

RESULTS

Over time, older people's diets were shifting towards a modern dietary pattern (high intake of dairy, fruit, cakes and fast food). Traditional and modern dietary patterns had distinct associations with BMI, Wt and WC. Participants with a diet in the highest quartile for traditional composition had a β (difference in mean) of -0.23 (95 % CI: -0.44; -0.02) for BMI decrease, β of -0.90 (95 % CI: -1.42; -0.37) for Wt decrease; and β of -1.57 (95 % CI: -2.32; -0.83) for WC decrease. However, participants with a diet in the highest quartile for modern diet had a β of 0.29 (95 % CI: 0.12; 0.47) for BMI increase; β of 1.02 (95 % CI: 0.58; 1.46) for Wt increase; and β of 1.44 (95 % CI: 0.78; 2.10) for Wt increase. No significant associations were found between dietary patterns and hypertension.

CONCLUSIONS

We elucidate the associations between dietary pattern and change in BMI, Wt, WC and hypertension in a 7-year follow-up study. The strong association between favourable body composition and traditional diet, compared with an increase in BMI, WC and Wt with modern diet suggests that there is an urgent need to develop age-specific dietary guideline for older Chinese people.

Effects of chronic sleep deprivation on glucose homeostasis in rats

Epidemiological studies have shown that chronic sleep disturbances resulted in metabolic disorders. The purpose of this study was to assess the relationship between chronic sleep deprivation (CSD) and the glucose homeostasis in rats. Twenty-four rats were randomly divided into CSD group and control (CON) group. The CSD rats were intervened by a modified multiple platform method (MMPM) to establish an animal model of chronic sleep disturbances. After 3-month intervention, all rats were subjected to an intraperitoneal glucose tolerance test (IPGTT) and an insulin tolerance test (ITT), and the body weight, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, lipid profile group, and homeostasis model assessment-IR (HOMA-IR) were measured. Both the CSD and CON groups had an attenuation of weight gain after 3-month intervention. The plasma glucose level of CSD group was higher than that of the CON group during the IPGTT (P < 0.01). The CSD rats showed a marked increase in HOMA-IR and ITT compared with the CON group (P < 0.01). There were no significant differences of AST, ALT, creatinine, and most lipid parameters between the CSD and CON groups (P > 0.05). The CSD has a marked effect on glucose homeostasis, comprising glucose intolerance and insulin resistance.

Physical activity and weight loss are independent predictors of improved insulin sensitivity following energy restriction

OBJECTIVE

The role of physical activity and the joint effect with sleep duration on insulin sensitivity (IS) during energy restriction followed by weight maintenance were determined.

METHODS

One hundred and two subjects (28 males) (mean ± SD age: 40 ± 9 years; BMI: 31.9 ± 3.0 kg/m(2) ) followed a very-low-energy diet for 8 weeks, followed by a 44-week period of weight maintenance. Body composition (three-compartment model based on body weight, total body water, and body volume), physical activity (accelerometry), sleep (questionnaire, Epworth Sleepiness Scale), and fasting plasma insulin and glucose concentrations were assessed before the diet and at 8, 20, and 52 weeks after the start.

RESULTS

Compared to baseline, IS was improved significantly after 8 weeks (P < 0.001) and was higher after 20 weeks (P < 0.001) and 52 weeks (P < 0.05). After 8, 20, and 52 weeks, 23% (P < 0.01), 19% (P < 0.05), and 13% (P < 0.05), respectively, of the variance in IS improvement was explained by weight loss percentage and change in physical activity counts.

CONCLUSIONS

Maintaining daily physical activity during energy restriction is as important as weight loss itself in the improvement of IS; there was no additional effect of change in sleep duration. During weight maintenance, improved IS is maintained better if physical activity returns to baseline or higher.

Dietary pattern, serum magnesium, ferritin, C-reactive protein and anaemia among older people

BACKGROUND & AIMS

Epidemiological data of dietary patterns and anaemia among older Chinese remains extremely scarce. We examined the association between dietary patterns and anaemia in older Chinese, and to assess whether biomarkers of serum magnesium, C-reactive protein (CRP) and serum ferritin can mediate these associations.

METHODS

We analysed the 2009 China Health and Nutrition Survey data (2401 individuals aged ≥60 years for whom both dietary and biomarker data are available). Dietary data was obtained using 24 h-recall over three consecutive days. Fasting blood samples and anthropometry measurement were also collected. Factor analysis was used to identify dietary patterns. Factor scores representing dietary patterns were used in Poisson regression models to explore the association between each dietary pattern and anaemia.

RESULTS

Of the 2401 participants, 18.9% had anaemia, 1.9% had anaemia related to inflammation (AI), and 1.3% had iron-deficiency anaemia (IDA). A traditional dietary pattern (high intake of rice, pork and vegetables) was positively associated with anaemia; a modern dietary pattern (high intake of fruit and fast food) was inversely associated with anaemia. Progressively lower magnesium and BMI levels were associated with increasing traditional dietary quartiles; while a progressively higher magnesium and BMI levels were associated with increasing modern dietary quartiles (p < 0.001). There were no significant differences (p > 0.05) in CRP and serum ferritin across quartiles for either dietary pattern. In the fully adjusted model, the prevalence ratio (PR) of anaemia, comparing the fourth quartile to the first quartile, was 1.75 (95% CI: 1.33; 2.29) for a traditional dietary pattern, and 0.89 (95% CI: 0.68; 1.16) for a modern dietary pattern. The association between dietary patterns and anaemia is mediated by serum magnesium.

CONCLUSION

Traditional dietary pattern is associated with a higher prevalence of anaemia among older Chinese. Future studies need to examine whether correcting micronutrient deficiency (e.g. magnesium) by promoting overall healthy diet, rather than iron supplementation, is a suitable strategy for anaemia prevention in older Chinese people.

Sleep Optimization and Diabetes Control: A Review of the Literature

Pre-diabetes and diabetes occur secondary to a constellation of pathophysiological abnormalities that culminate in insulin resistance, which results in reduced cellular glucose uptake and increased glucose production. Although pre-diabetes and diabetes have a strong genetic basis, they are largely environmentally driven through lifestyle factors. Traditional lifestyle factors such as diet and physical activity do not fully explain the dramatic rise in the incidence and prevalence of diabetes mellitus. Sleep has emerged as an additional lifestyle behavior, important for metabolic health and energy homeostasis. In this article, we review the current evidence surrounding the sleep-diabetes association.

Dietary Pattern Is Associated with Obesity in Older People in China: Data from China Health and Nutrition Survey (CHNS)

Background: No studies have been conducted to explore the associations between dietary patterns and obesity among older Chinese people, by considering gender and urbanization level differences. Methods: We analyzed data from the 2009 China Health and Nutrition Survey (2745 individuals, aged ≥ 60 years). Dietary data were obtained using 24 h-recall over three consecutive days. Height, Body Weight, and Waist Circumference were measured. Exploratory factor analysis was used to identify dietary patterns. Multinomial and Poisson regression models were used to examine the association between dietary patterns and Body Mass Index (BMI) status/central obesity. Results: The prevalence of general and central obesity was 9.5% and 53.4%. Traditional dietary pattern (high intake of rice, pork and vegetables) was inversely associated with general/central obesity; modern dietary pattern (high intake of fruit, fast food, and processed meat) was positively associated with general/central obesity. The highest quartile of traditional dietary pattern had a lower risk of general/central obesity compared with the lowest quartile, while an inverse picture was found for the modern dietary pattern. These associations were consistent by gender and urbanization levels. Conclusions: Dietary patterns are associated with general/central obesity in older Chinese. This study reinforces the importance of a healthy diet in promoting healthy ageing in China.

Dietary Patterns Modulate the Risk of Non-Alcoholic Fatty Liver Disease in Chinese Adults

Although previous studies reported the associations between the intakes of individual foods or nutrients and the risk of non-alcoholic fatty liver disease (NAFLD), the relationship between dietary patterns and NAFLD in the Chinese population has been rarely studied to date. This study aimed to investigate the associations between dietary patterns and the risk of NAFLD in a middle-aged Chinese population. The Study subjects were 999 Chinese adults aged 45–60 years in the Anhui province who participated in the Hefei Nutrition and Health Study. Dietary intake was collected by a semi-quantitative food frequency questionnaire. NAFLD was defined as the presence of moderate-severe hepatic steatosis (by B-ultrasonic examination); the absence of excessive alcohol use (>20 g day⁻¹ in men and 10 g day⁻¹ in women); no use of steatogenic medications within the past six months; no exposure to hepatotoxins; and no history of bariatric surgery. Log-binomial regression analysis was used to examine the association between dietary patterns and NAFLD with adjustment of potential confounding variables. Out of 999 participants, 345 (34.5%) were classified as having NAFLD. Four major dietary patterns were identified: “Traditional Chinese”, “Animal food”, “Grains-vegetables” and “High-salt” dietary patterns. After adjusting for potential confounders, subjects in the highest quartile of the “Animal food” pattern scores had greater prevalence ratio for NAFLD (prevalence ratio (PR) = 1.354; 95% confidence interval (CI): 1.063–1.724; p < 0.05) than did those in the lowest quartile. After adjustment for body mass index (BMI), compared with the lowest quartile of the “Grains-vegetables” pattern, the highest quartile had a lower prevalence ratio for NAFLD (PR = 0.777; 95% CI: 0.618–0.977, p < 0.05). However, the “traditional Chinese” and “high-salt” dietary patterns showed no association with the risk of NAFLD. Our findings indicated that the “Animal food” dietary pattern was associated with an increased risk of NAFLD.

Sleep disturbances in adults in a city of Sao Paulo state

OBJECTIVE

To analyze the occurrence of sleep-related disorders among adults from Presidente Prudente, Brazil, as well as to identify associations with behavioral, socio-demographic and nutritional status variables.

METHODS

After random selection of the sample, interviews were performed with 743 adults of both genders, living in Presidente Prudente, Brazil. Sleep-related disorders, demographic variables (sex, age, ethnicity and schooling), behavioral variables (leisure physical activity, alcohol consumption, and smoking) and nutritional status were analyzed by questionnaires.

RESULTS

The prevalence of sleep-related disorders was 46.7%, with 95% confidence interval (95%CI) 43.1 - 50.2. In the multivariate analysis, female sex, with odds ratio (OR) 1.74 (95%CI 1.26 - 2.40), schooling (OR = 0.49; 95%CI 0.28 - 0.82), overweight (OR = 1.99; 95%CI 1.39 - 2.85) and obesity (OR = 2.90; 95%CI 1.94 - 4.35) were associated with sleep-related disorders.

CONCLUSION

There is high occurrence of sleep-related disorders in this sample, which was associated with female sex, lower schooling, overweight and obesity.

Association of napping and night-time sleep with impaired glucose regulation, insulin resistance and glycated haemoglobin in Chinese middle-aged adults with no diabetes: a cross-sectional study

OBJECTIVE

To assess associations between napping and night-time sleep duration with impaired glucose regulation, insulin resistance (IR) and glycated haemoglobin (HbA1c).

DESIGN

Cross-sectional study.

SETTING

Fujian Province, China, from June 2011 to January 2012.

PARTICIPANTS

This study enrolled 9028 participants aged 40-65 years. Data of 7568 participants with no diabetes were included for analysis. Type 2 diabetes was defined applying WHO criteria.

OUTCOME MEASURES

Participants' daytime napping and night-time sleep duration data were collected using a standardised self-reported Chinese-language questionnaire about sleep frequency and quality. Anthropometric and laboratory parameters were also measured. IR was defined as a HOMA-IR index value >2.50. ORs and 95% CIs were derived from multivariate logistic regression models.

RESULTS

Participants (mean age 51.1±7.0 years) included 3060 males and 4508 females with average night-time sleep of 7.9 h. A higher proportion of males napped than females. After adjustment for potential confounders, ORs for HbA1c >6.0% were 1.28 and 1.26 for those napping ≤1 h and >1 h (p=0.002 and p=0.018), respectively. Statistically significant differences in IR between nappers and non-nappers were only marginal clinically. Odds for HbA1c >6.0% were significantly lower in participants with longer night-time sleep durations than in the reference group (>8 h vs 6-8 h). Odds for IR were significantly lower in participants whose night-time sleep hours deviated from the reference group (<6 h, >8 h vs 6-8 h)

CONCLUSIONS

Chinese middle-aged adults with no diabetes who napped had higher HbA1c and IR; those with shorter night-time sleep durations had increased HbA1c. Night-time sleep hours that are either <6 or >8 tend to be associated with lower odds for IR. Further studies are necessary to determine the underlying clinical significance and mechanisms behind these associations.

Serum leptin concentrations in relation to dietary patterns in Chinese men and women

OBJECTIVE

The present study aimed to evaluate the independent associations between serum leptin concentration and dietary patterns in a Chinese population.

DESIGN

A cross-sectional study.

SETTING

Data obtained from the 2006 wave of the China Health and Nutrition Survey in Jiangsu Province, China.

SUBJECTS

The sample contained 1061 Chinese adults (488 men and 573 women). BMI was calculated as a parameter of obesity. Factor analysis was used to derive dietary patterns. ANCOVA was performed to assess the associations between serum leptin concentration and the dietary patterns.

RESULTS

Four dietary patterns were derived: Western, High-wheat, Traditional and Hedonic. The Western pattern (rich in meat, milk and cake) was significantly associated with a higher level of serum leptin in men and women, both in an unadjusted model (both P for trend < 0·001) and after adjusting for sex, age, income, total energy intake, physical activity, smoking status and BMI (P for trend = 0·007 for men and P for trend < 0·001 for women). The other three dietary patterns were not significantly associated with serum leptin after adjustment. Sensitivity analysis showed there was an interaction between age and the Western pattern in relation to leptin level. An interaction also existed between current smoking status and the Western pattern.

CONCLUSIONS

Serum leptin concentration was positively associated with the Western dietary pattern in a Chinese population independent of BMI, energy intake and other factors.

Associations between self-reported sleep duration and sleeping disorder with concentrations of fasting and 2-h glucose, insulin, and glycosylated hemoglobin among adults without diagnosed diabetes

BACKGROUND

There is limited information from population-based investigations of the associations between sleep duration and sleep disorders and parameters of glucose homeostasis. The objective of the present study was to examine cross-sectional associations between sleep duration and sleep disordered breathing with concentrations of insulin, fasting and 2-h glucose, and HbA1c.

METHODS

Data from 11 815 adults aged ≥20 years without diagnosed diabetes (5002 with an oral glucose tolerance test) from the National Health and Nutrition Examination Survey 2005-2010 were used. Information about sleep duration (2005-2010) and sleep apnea and sleep-disordered breathing (2005-2008) was obtained via questionnaire.

RESULTS

An estimated 36.0% of participants reported sleeping ≤6 h/night, 62.0% reported sleeping 7-9 h/night, and 2.0% reported sleeping ≥10 h/night. In 2005-2008, 33.0% reported snoring ≥5 nights per week, 5.9% reported they snorted, gasped, or stopped breathing ≥5 nights/week, and 4.2% reported sleep apnea. Sleep duration was significantly associated with fasting concentrations of insulin and concentrations of HbA1c only in models that did not adjust for body mass index (BMI). Concentrations of fasting and 2-h glucose were significantly associated with sleep duration in models that adjusted only for age. Snoring frequency was positively associated with concentrations of insulin and HbA1c. Frequency of snorting or stopping breathing and sleep apnea status were associated with concentrations of insulin and of HbA1c only when BMI was not accounted for.

CONCLUSION

In a representative sample of US adults, concentrations of insulin and HbA1c were significantly associated with short sleep duration, possibly mediated by BMI.

Addressing sleep disturbances: an opportunity to prevent cardiometabolic disease?

There is increasing awareness of the role of sleep disturbance as an important factor in health and disease. Although sub-clinical sleep disturbances (insufficient sleep duration or inadequate sleep quality) may be difficult to assess with conceptual and/or methodological clarity, this review attempts to summarize and synthesize these findings. First, the concept of sleep disturbance in a public health context is introduced, to provide context and rationale. Second, operational definitions of 'cardiometabolic disease' and 'sleep disturbance' are offered, to address many unclear operationalizations. Third, the extant literature is summarized regarding short or long sleep duration and/or insufficient sleep, insomnia and insomnia symptoms, general (non-specific sleep disturbances), circadian rhythm abnormalities that result in sleep disturbances, and, briefly, sleep-disordered breathing. Fourth, the review highlights the social/behavioural context of sleep, including discussions of sleep and race/ethnicity, socio-economic position, and other social/environmental factors, in order to place these findings in a social-environmental context relevant to public health. Fifth, the review highlights the issue of sleep as a domain of health behaviour and addresses issues regarding development of healthy sleep interventions. Finally, a research agenda of future directions is proposed.

Sleep duration and glycemic control in patients with diabetes mellitus: Korea National Health and Nutrition Examination Survey 2007-2010

Short sleep duration has been reported to increase the risk of diabetes. However, the influence of sleep duration on glycemic control in diabetic patients has not been clarified. In this study we evaluated the association between sleep duration and glycemic control in diabetic patients. We analyzed the data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2007-2010. Sleep duration was classified into five groups: <6, 6, 7, 8, and ≥9 h/day. Fasting blood glucose and HbA1c showed a U-shaped trend according to sleep duration. Sleep duration of 7 h/day had the lowest HbA1c (7.26%) among the subjects (P=0.026). In the older age group (≥65 yr), a sleep duration of 6 h/day was associated with the lowest HbA1c (7.26%). The adjusted odds ratio (OR) with a 95% confidence interval (CI) of worse glycemic control (HbA1c ≥7.0%) in group of sleep duration of ≥9 h/day was 1.48 (1.04-2.13) compared with the group of 7 h/day. This relationship disappeared after adjusting duration of diabetes (OR, 1.38; 95% CI, 0.93-2.03). Our results suggest that sleep duration and glycemic control in diabetic patients has U-shaped relationship which was mainly affected by duration of diabetes.

Association between serum leptin concentrations and insulin resistance: a population-based study from China

Background

Insulin resistance contributes to the cardio-metabolic risk. The effect of leptin in obese and overweight population on insulin resistance was seldom reported.

Methods

A total of 1234 subjects (572 men and 662 women) aged ≥18 y was sampled by the procedure. Adiposity measures included BMI, waist circumference, hip circumference, WHR, upper arm circumference, triceps skinfold and body fat percentage. Serum leptin concentrations were measured by an ELISA method. The homeostasis model (HOMA-IR) was applied to estimate insulin resistance.

Results

In men, BMI was the variable which was most strongly correlated with leptin, whereas triceps skinfold was most sensitive for women. More importantly, serum leptin levels among insulin resistant subjects were almost double compared to the subjects who had normal insulin sensitivity at the same level of adiposity in both men and women, after controlling for potential confounders. In addition, HOMA-IR increased significantly across leptin quintiles after adjustment for age, BMI, total energy intake, physical activity and smoking status in both men and women (p for trend <0.0001).

Conclusions

There was a significant association between HOMA-IR and serum leptin concentrations in Chinese men and women, independently of adiposity levels. This may suggest that serum leptin concentration is an important predictor of insulin resistance and other metabolic risks irrespective of obesity levels. Furthermore, leptin levels may be used to identify the cardio-metabolic risk in obese and overweight population.