Sleep duration in elderly obese patients correlated negatively with intake fatty

Dietary amino acid intake and sleep duration are additively involved in future cognitive decline in Japanese adults aged 60 years or over: a community-based longitudinal study

BACKGROUND

Sleep duration and amino acid intake are independently associated with cognitive decline. This study aimed to determine the longitudinal association between sleep duration and cognitive impairment incidence and to examine the involvement of diet, particularly amino acid intake, in these associations in community dwellers.

METHODS

In this longitudinal study in a community-based setting, we analyzed data from 623 adults aged 60-83 years without cognitive impairment at baseline. Sleep duration was assessed using a self-report questionnaire. Amino acid intake was assessed using 3-day dietary records. Cognitive impairment was defined as a Mini-Mental State Examination score ≤ 27. Participants were classified into short-, moderate-, and long-sleep groups according to baseline sleep duration (≤ 6, 7-8, and > 8 h, respectively). Using moderate sleep as a reference, odds ratios (ORs) and 95% confidence intervals (CIs) of short- and long-sleep for cognitive-impairment incidence were estimated using the generalized estimating equation. Participants were classified according to sex-stratified quartiles (Q) of 19 amino acid intake: Q1 and Q2-Q4 were low- and middle to high-intake groups, respectively. Using middle- to high-intake as a reference, ORs and 95% CIs of low intake for cognitive impairment incidence were estimated using the generalized estimating equation in each sleep-duration group. Follow-up period, sex, age, body mass index, depressive symptoms, education, smoking status, employment status, sleep aids use, physical activity, medical history, and Mini-Mental State Examination score at baseline were covariates.

RESULTS

Mean follow-up period was 6.9 ± 2.1 years. Adjusted ORs (95% CIs) for cognitive impairment in short- and long-sleep groups were 0.81 (0.49-1.35, P = 0.423) and 1.41 (1.05-1.87, P = 0.020), respectively. Particularly in long sleepers (i.e., > 8 h), cognitive impairment was significantly associated with low cystine, proline, and serine intake [adjusted ORs (95% CIs) for cognitive impairment were 2.17 (1.15-4.11, P = 0.017), 1.86 (1.07-3.23, P = 0.027), and 2.21 (1.14-4.29, P = 0.019), respectively].

CONCLUSIONS

Community-dwelling adults aged ≥ 60 years who sleep longer are more likely to have cognitive decline, and attention should be paid to the low cystine, proline, and serine intake.

The interplay between macronutrients and sleep: focus on circadian and homeostatic processes

Sleep disturbances are an emerging risk factor for metabolic diseases, for which the burden is particularly worrying worldwide. The importance of sleep for metabolic health is being increasingly recognized, and not only the amount of sleep plays an important role, but also its quality. In this review, we studied the evidence in the literature on macronutrients and their influence on sleep, focusing on the mechanisms that may lay behind this interaction. In particular, we focused on the effects of macronutrients on circadian and homeostatic processes of sleep in preclinical models, and reviewed the evidence of clinical studies in humans. Given the importance of sleep for health, and the role of circadian biology in healthy sleep, it is important to understand how macronutrients regulate circadian clocks and sleep homeostasis.

The association between cholesterol/saturated fat index (CSI) and quality of sleep, and circadian rhythm among overweight and obese women: a cross-sectional study

BACKGROUND

The decline in sleep quality is one of the main public health problems affecting the global population. Some studies have shown that a high-fat diet may be linked to changes in circadian rhythm and sleep quality. The cholesterol/saturated fatty acid index (CSI) determines the amount of cholesterol and saturated fatty acid (SFA) in people's dietary patterns and can affect the quality of sleep and circadian rhythm. However, to date, no studies have investigated the effect of this index on these two variables. Therefore, our aim was to investigate the relationship between CSI on circadian rhythm and sleep quality in obese and overweight women.

METHOD

This cross-sectional study included 378 adult women who were obese or overweight. Using accepted techniques, anthropometric measurements, blood pressure readings, and biochemical variables were evaluated. A validated and trustworthy semi-quantitative food frequency questionnaire (FFQ 147 items) was used to gauge dietary intake. The CSI was measured to find out how much cholesterol and saturated fats were in the diet. Additionally, to assess circadian rhythm and sleep quality, respectively, the valid morning-evening questionnaire (MEQ) and Pittsburgh sleep quality index (PSQI) questionnaires were utilized.

RESULT

The results of the multinomial logistic regression model of our analysis showed that a significant association was observed between circadian rhythm status with CSI score, and participants with one higher unit of CSI had a 7.3% more chance of being in the eveningness group than being in morningness category in the crude model (OR: 1.07; 95% CI 1.00, 1.14; P = 0.026). This association remains marginally significant when adjusting for age, energy intake, BMI, job status, thyroid, and smoking status (OR = 1.08; 95% CI 1.00, 1.16; P = 0.051). The binary logistic regression model showed that after controlling for potentially confounding variables, there was no significant association between sleep quality with CSI score, however, those with one higher unit of CSI had 1.6% more chance of having sleep problems (OR: 1.01; 95% CI 0.96, 1.06; P = 0.503).

CONCLUSION

Our results indicated a direct marginally significant association between CSI with evening type in overweight and obese women. Future studies are needed to clarify the precise link between circadian rhythm and sleep behavior with fatty acid quality index.

Chronobiology and Metabolism: Is Ketogenic Diet Able to Influence Circadian Rhythm?

Circadian rhythms underpin most physiological processes, including energy metabolism. The core circadian clock consists of a transcription-translation negative feedback loop, and is synchronized to light-dark cycles by virtue of light input from the retina, to the central clock in the suprachiasmatic nucleus in the hypothalamus. All cells in the body have circadian oscillators which are entrained to the central clock by neural and humoral signals. In addition to light entrainment of the central clock in the brain, it now emerges that other stimuli can drive circadian clock function in peripheral tissues, the major one being food. This can then drive the liver clock to be misaligned with the central brain clock, a situation of internal misalignment with metabolic disease consequences. Such misalignment is prevalent, with shift workers making up 20% of the working population. The effects of diet composition on the clock are not completely clarified yet. High-fat diet and fasting influence circadian expression of clock genes, inducing phase-advance and phase-delay in animal models. Ketogenic diet (KD) is able to induce a metabolic switch from carbohydrate to fatty acid oxidation, miming a fasting state. In recent years, some animal studies have been conducted to investigate the ability of the KD to modify circadian gene expression, and demonstrated that the KD alters circadian rhythm and induces a rearrangement of metabolic gene expression. These findings may lead to new approaches to obesity and metabolic pathologies treatment.

Genetically Predicted Insomnia in Relation to 14 Cardiovascular Conditions and 17 Cardiometabolic Risk Factors: A Mendelian Randomization Study

Background

This Mendelian randomization study aims to investigate causal associations between genetically predicted insomnia and 14 cardiovascular diseases (CVDs) as well as the potential mediator role of 17 cardiometabolic risk factors.

Methods and Results

Using genetic association estimates from large genome‐wide association studies and UK Biobank, we performed a 2‐sample Mendelian randomization analysis to estimate the associations of insomnia with 14 CVD conditions in the primary analysis. Then mediation analysis was conducted to explore the potential mediator role of 17 cardiometabolic risk factors using a network Mendelian randomization design. After correcting for multiple testing, genetically predicted insomnia was consistent significantly positively associated with 9 of 14 CVDs, those odds ratios ranged from 1.13 (95% CI, 1.08–1.18) for atrial fibrillation to 1.24 (95% CI, 1.16–1.32) for heart failure. Moreover, genetically predicted insomnia was consistently associated with higher body mass index, triglycerides, and lower high‐density lipoprotein cholesterol, each of which may act as a mediator in the causal pathway from insomnia to several CVD outcomes. Additionally, we found very little evidence to support a causal link between insomnia with abdominal aortic aneurysm, thoracic aortic aneurysm, total cholesterol, low‐density lipoprotein cholesterol, glycemic traits, renal function, and heart rate increase during exercise. Finally, we found no evidence of causal associations of genetically predicted body mass index, high‐density lipoprotein cholesterol, or triglycerides on insomnia.

Conclusions

This study provides evidence that insomnia is associated with 9 of 14 CVD outcomes, some of which may be partially mediated by 1 or more of higher body mass index, triglycerides, and lower high‐density lipoprotein cholesterol.

The chronotype conjecture in the association between dietary carbohydrate intake and high-sensitivity C-reactive protein (hs-CRP): a cross-sectional study from NHANES 2015 data

Substantial evidence suggests that the timing of macronutrient intake affects cardiovascular health. The present study aims to assess the association between the dietary carbohydrate intake (DCI) and the high-sensitivity C-reactive protein (hs-CRP) combined with the implication of the chronotype. Thus, we explored the most recently released National Health and Nutrition Examination Survey (NHANES) data. We analysed data from 5,616 participants of the NHANES in 2015. We selected participants with available data for the DCI, sleep and wake-up time, and the hs-CRP. Chronotypes were categorized according to the sleep times. Binary logistic regression analysis was performed to predict participants with low or high levels of hs-CRP based on the DCI and chronotypes. Moderation analysis was used to investigate the effect of the chronotypes on the DCI-hs-CRP's association. A higher DCI was significantly associated with the higher hs-CRP levels (odds ratio (OR) = 1.36, 95% confidence interval (CI) = [0.9-1.8]). Moderate evening (ME) chronotypes had higher risk for high hs-CRP level (OR = 1.15, 95% CI = [1.22-1.23]) compared to the intermediate and the morning chronotypes. The chronotype significantly moderated the hs-CRP given the DCI (moderation coefficient, α2=0.05, 95% CI = [0.01-0.08]). The chronotype diminished the hs-CRP predicted by the DCI. The findings of the study underscore the significance of assessing the protective effect of individuals' chronotype concerning cardiovascular health.

Association of Sleep Quality and Macronutrient Distribution: A Systematic Review and Meta-Regression

Sleep is involved in metabolic, emotional and cognitive regulation and is therefore an essential part of our health. Although an association between sleep quality and macronutrient intake has been reported, studies on the effect of macronutrient distribution with sleep quality are limited, and available results are inconsistent. In this study, we aim to assess the association between sleep quality and macronutrient distribution in healthy adults from systematically reviewed cross-sectional studies and randomized controlled trials (RCTs). A total of 19 relevant articles were selected and it was observed that good sleepers (sleep duration ≥ 7 h, global sleep score ≤ 5, sleep latency ≤ 30 min and sleep efficiency >85%) had a higher energy distribution from dietary protein than poor sleepers. On the other hand, good sleepers showed a relatively lower percentage of energy from dietary carbohydrate and fat than poor sleepers. However, meta-regression analysis revealed no dose-dependent association between the macronutrient distributions and sleep duration. These results suggest that consuming a greater proportion of dietary protein may benefit on improving sleep quality in healthy adults. However, findings may be susceptible to reverse causality and additional RCTs are needed.

Sleep duration is associated with healthy diet scores and meal patterns: results from the population-based EpiHealth study

STUDY OBJECTIVES

To investigate relationships between sleep duration and adherence to healthy diets, but also associations with meal patterns, in a large population-based cohort.

METHODS

Participants (n = 23,829, males and females, aged 45 to 75 years) from the Swedish EpiHealth cohort study were included in a cross-sectional analysis. The participants filled out an extensive Internet-based questionnaire, and also visited a test center for anthropometric measurements and blood sampling. Sleep duration was classified as short (< 6 h/night; n = 1,862), normal (6 to less fewer than 9 h/night; n = 19,907) and long sleep (≥ 9 h/night; n = 858). In addition, a combination variable of sleep duration (short/normal/long) and sleep quality (good/poor) was constructed, giving six categories. Adherence to a healthy diet was assessed using the modified Mediterranean diet (mMED) score and the Healthy Nordic Food Index (HNFI) score based on food groups from a food frequency questionnaire. A regular meal pattern was considered if the participant had breakfast, lunch and dinner on a daily basis.

RESULTS

Compared with normal sleepers, short sleepers displayed lower adherence to a healthy diet when using both the mMED score (adjusted odds ratio = 0.70; 95% confidence interval 0.56-0.88) and the HNFI score (0.70; 0.56-0.88). When combining sleep duration and sleep quality, short sleepers with poor sleep quality showed an independent relationship with low adherence to a healthy diet (0.67; 0.52-0.86) compared with normal sleepers with good sleep quality. In addition, both short sleepers (0.71; 0.62-0.82) and long sleepers (0.75; 0.62-0.91) showed low adherence to regular meal patterns, compared with normal sleepers. Furthermore, short sleepers with poor sleep quality had reduced odds of having a regular meal pattern (0.67; 0.57-0.79) as compared with normal sleepers with good sleep quality.

CONCLUSIONS

Short sleep duration combined with poor sleep quality is associated with low adherence to a healthy diet and regular meal patterns.

Dietary Protein and Amino Acid Intake: Links to the Maintenance of Cognitive Health

With the rapid growth in the aging population, there has been a subsequent increase in the rates of Alzheimer's disease and related dementias (ADRD). To combat these increases in ADRD, scientists and clinicians have begun to place an increased emphasis on preventative methods to ameliorate disease rates, with a primary focus area on dietary intake. Protein/amino acid intake is a burgeoning area of research as it relates to the prevention of ADRD, and consumption is directly related to a number of disease-related risk factors as such low-muscle mass, sleep, stress, depression, and anxiety. As a result, the role that protein/amino acid intake plays in affecting modifiable risk factors for cognitive decline has provided a robust area for scientific exploration; however, this research is still speculative and specific mechanisms have to be proven. The purpose of this review is to describe the current understanding of protein and amino acids and the preventative roles they play with regard to ADRD, while providing future recommendations for this body of research. Additionally, we will discuss the current recommendations for protein intake and how much protein older adults should consume in order to properly manage their long-term risk for cognitive decline.

Diet quality, consumption of seafood and eggs are associated with sleep quality among Chinese urban adults: A cross-sectional study in eight cities of China

Growing evidence has suggested that dietary modification is implicated with sleep alteration. Our study aimed to determine whether an association between diet in terms of diet quality, certain food consumption, and dietary nutrients intake and sleep quality existed in Chinese urban adults, which has been fully investigated. A cross-sectional study was conducted among urban adults from eight Chinese cities. Total of 1,548 participants remained in the final analysis. Sleep quality was evaluated by the Chinese version of the Pittsburg Sleep Questionnaire Index. Diet quality, evaluated by Chinese Healthy Diet Index, and dietary intake, including food groups and nutrients, were derived from a semiquantitative Food Intake Frequencies Questionnaire and a single 24-hr dietary recall. The relationship between dietary variables and sleep quality was examined using multivariable logistic regression models. Logistic regression analysis indicated that better diet quality, which features greater food diversity, higher ingestion of fruits and fish, along with higher seafood consumption, lower eggs consumption, and higher total energy intake, was significantly associated with lower risk of poor sleep quality in the crude model and the fully adjusted model with adjustment for gender, age, self-rated health condition, self-assessed mental stress, smoking, hypertension, and BMI. Therefore, we reached a conclusion that diet quality and certain food consumption were related to sleep quality. Although the associations observed in the cross-sectional study require further investigation in prospective studies, dietary intervention, such as enhancement in food diversity and consumption of fruits and seafood, might serve as a probable strategy for sleep improvement.

The associations between carbohydrate and protein intakes with habitual sleep duration among adults living in urban and rural areas

BACKGROUND & AIMS

Macronutrient intake was associated with habitual sleep duration, a recognized metabolic risk factor. However, results are not clear for populations with large diversities in dietary habits and urbanization levels. In this study, we aimed to evaluate the associations between relative macronutrient intakes and sleep duration, and the potential modification effect of urban-rural residence among adult Chinese population.

METHODS

We analyzed data from the China Health and Nutrition Survey 2009. In total, 9239 men and women aged 18 years or older were included. Dietary intakes were measured using a combination of a 3-day recall and household-based food weighing approach. Sleep duration was self-reported as hours of sleeping every 24 h.

RESULTS

Our participants have a mean sleep duration of 7.9 ± 1.2 h. After multivariate adjustment, higher intake of carbohydrate as percentage of total energy was associated with longer sleep duration (β ± SE = 0.43 ± 0.12, P < 0.001); and an inverse association was observed for the relative protein intake (β ± SE = -2.12 ± 0.47, P < 0.001). After stratification, the inverse association for protein was only detected in rural residents (β ± SE = -3.30 ± 0.66, P < 0.001), but not in urban participants (β ± SE = -0.44 ± 0.74, P = 0.55) (P for interaction = 0.002). Similarly, a marginal interaction with residence was observed for carbohydrate-sleep association.

CONCLUSIONS

Our study suggested that the relative intakes of protein/carbohydrate were associated with sleep duration among adult Chinese, especially those in rural areas.

Dietary Macronutrients and Sleep

This study examined the effects of macronutrient diets on sleep quantity and quality. Using a repeated-measures, randomized crossover study design, 36 young adults served as their own control, and consumed high protein, carbohydrate, fat, and control diets. Treatment orders were counterbalanced across the dietary groups. Following consumption of the study diets, sleep measures were examined for within-subject differences. Fatty acid intakes and serum lipids were further analyzed for differences. Sleep actigraphs indicated wake times and wake minutes (after sleep onset) were significantly different when comparing consumption of macronutrient diets and a control diet. Post hoc testing indicated high carbohydrate intakes were associated with significantly shorter (p < .001) wake times. Also, the Global Pittsburgh Sleep Quality Index© post hoc results indicated high fat intake was associated with significantly better (p < .05) sleep in comparison with the other diets. These results highlight the effects that dietary manipulations may have on sleep.

Higher-protein diets improve indexes of sleep in energy-restricted overweight and obese adults: results from 2 randomized controlled trials

BACKGROUND

Limited and inconsistent research findings exist about the effect of dietary protein intake on indexes of sleep.

OBJECTIVE

We assessed the effect of protein intake during dietary energy restriction on indexes of sleep in overweight and obese adults in 2 randomized, controlled feeding studies.

DESIGN

For study 1, 14 participants [3 men and 11 women; mean ± SE age: 56 ± 3 y; body mass index (BMI; in kg/m(2)): 30.9 ± 0.6] consumed energy-restricted diets (a 750-kcal/d deficit) with either beef and pork (BP; n = 5) or soy and legume (SL; n = 9) as the main protein sources for 3 consecutive 4-wk periods with 10% (control), 20%, or 30% of total energy from protein (random order). At baseline and the end of each period, the global sleep score (GSS) was assessed with the use of the Pittsburgh Sleep Quality Index (PSQI) questionnaire. For study 2, 44 participants (12 men and 32 women; age: 52 ± 1 y; BMI: 31.4 ± 0.5) consumed a 3-wk baseline energy-balance diet with 0.8 g protein · kg baseline body mass(-1) · d(-1). Then, study 2 subjects consumed either a normal-protein [NP (control); n = 23] or a high-protein (HP; n = 21) (0.8 compared with 1.5 g · kg(-1) · d(-1), respectively) energy-restricted diet (a 750-kcal/d deficit) for 16 wk. The PSQI was administered during baseline week 3 and intervention weeks 4, 8, 12, and 16. GSSs ranged from 0 to 21 arbitrary units (au), with a higher value representing a worse GSS during the preceding month.

RESULTS

In study 1, we showed that a higher protein quantity improved GSSs independent of the protein source. The GSS was higher (P < 0.05) when 10% (6.0 ± 0.4 au) compared with 20% (5.0 ± 0.4 au) protein was consumed, with 30% protein (5.4 ± 0.6 au) intermediate. In study 2, at baseline, the GSS was not different between NP (5.2 ± 0.5 au) and HP (5.4 ± 0.5 au) groups. Over time, the GSS was unchanged for the NP group and improved for the HP group (P-group-by-time interaction < 0.05). After intervention (week 16), GSSs for NP and HP groups were 5.9 ± 0.5 and 4.0 ± 0.6 au, respectively (P < 0.01).

CONCLUSION

The consumption of a greater proportion of energy from protein while dieting may improve sleep in overweight and obese adults. This trial was registered at clinicaltrials.gov as NCT01005563 (study 1) and NCT01692860 (study 2).

Short sleep duration and dietary intake: epidemiologic evidence, mechanisms, and health implications

Links between short sleep duration and obesity, type 2 diabetes, hypertension, and cardiovascular disease may be mediated through changes in dietary intake. This review provides an overview of recent epidemiologic studies on the relations between habitual short sleep duration and dietary intake in adults from 16 cross-sectional studies. The studies have observed consistent associations between short sleep duration and higher total energy intake and higher total fat intake, and limited evidence for lower fruit intake, and lower quality diets. Evidence also suggests that short sleepers may have irregular eating behavior deviating from the traditional 3 meals/d to fewer main meals and more frequent, smaller, energy-dense, and highly palatable snacks at night. Although the impact of short sleep duration on dietary intake tends to be small, if chronic, it may contribute to an increased risk of obesity and related chronic disease. Mechanisms mediating the associations between sleep duration and dietary intake are likely to be multifactorial and include differences in the appetite-related hormones leptin and ghrelin, hedonic pathways, extended hours for intake, and altered time of intake. Taking into account these epidemiologic relations and the evidence for causal relations between sleep loss and metabolism and cardiovascular function, health promotion strategies should emphasize improved sleep as an additional factor in health and weight management. Moreover, future sleep interventions in controlled studies and sleep extension trials in chronic short sleepers are imperative for establishing whether there is a causal relation between short sleep duration and changes in dietary intake.

Sleep Duration and Waist Circumference in Adults: A Meta-Analysis

BACKGROUND

Previous research has demonstrated a relation between insufficient sleep and overall obesity. Waist circumference (WC), a measure of central adiposity, has been demonstrated to improve prediction of health risk. However, recent research on the relation of insufficient sleep duration to WC in adults has yielded inconsistent findings.

OBJECTIVES

To assess the magnitude and the consistency of the relation of insufficient sleep and WC.

METHODS

A systematic search of Internet and research databases using Google Scholar, Medline, PubMed, and PsycINFO through July 2013 was conducted. All articles in English with adult human subjects that included measurements of WC and sleep duration were reviewed. A random effects meta-analysis and regression analyses were performed. Heterogeneity and publication bias were checked. Results are expressed as Pearson correlations (r; 95% confidence interval).

RESULTS

Of 1,376 articles, 30 met inclusion criteria and 21 studies (22 samples for a total of 56,259 participants) provided sufficient data for meta-analysis. Results showed a significant negative relation between sleep duration and WC (r = -0.10, P < 0.0001) with significant heterogeneity related to sleep comparison method. Potential moderators of the relation between sleep duration and WC were not significant. Funnel plots showed no indication of publication bias. In addition, a fail-safe N calculation indicated that 418 studies with null effects would be necessary to bring the overall mean effect size to a trivial value of r = -0.005.

CONCLUSIONS

Internationally, cross-sectional studies demonstrate a significant negative relation between sleep duration and waist circumference, indicating shorter sleep durations covary with central adiposity. Future research should include prospective studies.

Prevalence of dyslipidemia and its association with insomnia in a community based population in China

Background

Studies of the prevalence of dyslipidemia and its association with insomnia are scarce in China. This study investigated the prevalence of dyslipidemia and its association with insomnia in a community based Chinese population.

Methods

We conducted a cross-sectional survey in Beijing and recruited 10054 participants aged ≥18 years. The association between self-reported insomnia and dyslipidemia was determined by multiple logistic regression models. Age, gender, education, obesity, body mass index, physical activity, current smoking, current drinking, diabetes, and hypertension were adjusted as confounders. Odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were reported as effect measurements.

Results

The prevalence of dyslipidemia in those with no insomnia, occasional insomnia, and frequent insomnia were 53.3%, 54.3%, and 54.5% in men and 52.0%, 54.8%, and 61.2% in women. Compared with subjects with no insomnia, the multivariate adjusted ORs and 95% CIs for those with occasional insomnia and frequent insomnia were 1.07(0.86 ~ 1.34) and 1.19(0.89 ~ 1.60) for men, and 1.00(0.86 ~ 1.14) and 1.23(1.03 ~ 1.47) for women.

Conclusions

These observations indicate that frequent insomnia was associated with a higher prevalence of dyslipidemia in women. This association was not significant in men.

Sleep duration and abnormal serum lipids: the China Health and Nutrition Survey

OBJECTIVE

To examine the associations between sleep duration and total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), apolipoprotein B (ApoB), apolipoprotein A1 (ApoA1), and lipoprotein (a) [Lp(a)].

METHODS

The present study analyzed 8574 adults from the China Health and Nutrition Survey (2009). Sleep duration was classified into < or = 6, 7, 8, 9, and > or = 10 h. Age, education, occupation, current smoking, current drinking, physical activity, body mass index, hypertension, and diabetes were adjusted as confounders in gender-stratified multiple logistic regression models.

RESULTS

Compared with women reporting 8h sleep duration, the odds ratios (ORs) and 95% confidence intervals (CIs) of high TC for those with < or = 6, 7, 9, and > or = 10 h were 1.65 (1.32-2.06), 1.19 (1.00-1.43), 1.11 (0.89-1.39), and 1.27 (1.02-1.60) after adjusting for confounders. Likewise, the ORs (95% CIs) of high LDL-C were 1.71 (1.28-2.29), 1.36 (1.05-1.76), 1.04 (0.74-1.46), and 1.09 (0.78-1.53), whereas those of high ApoB were 1.80 (1.34-2.42), 1.15 (0.88-1.52), 0.95 (0.66-1.35), and 1.00 (0.70-1.43) for women with < or = 6, 7, 9, and > or = 10 h sleep duration, respectively. These associations were not statistically significant in men.

CONCLUSIONS

Both shorter and longer sleep durations were associated with higher risks of abnormal serum lipid profiles in women but not in men.

Sleep disorders and the development of insulin resistance and obesity

Normal sleep is characterized both by reduced glucose turnover by the brain and other metabolically active tissues, and by changes in glucose tolerance. Sleep duration has decreased over the last several decades; data suggest a link between short sleep duration and type 2 diabetes. Obstructive sleep apnea (OSA) results in intermittent hypoxia and sleep fragmentation, and also is associated with impaired glucose tolerance. Obesity is a major risk factor for OSA, but whether OSA leads to obesity is unclear. The quality and quantity of sleep may profoundly affect obesity and glucose tolerance, and should be routinely assessed by clinicians.