Associations of usual sleep duration with serum lipid and lipoprotein levels

Association between self-reported global sleep status and prevalence of hypertension in Chinese adults: data from the Kailuan community

BACKGROUND

Assessment of sleep only by sleep duration is not sufficient. This cross-sectional study aimed to investigate the potential association of self-reported global sleep status, which contained both qualitative and quantitative aspects, with hypertension prevalence in Chinese adults.

METHODS

A total of 5461 subjects (4076 of them were male) were enrolled in the current study and were divided into two groups with the age of 45 years as the cut-off value. Sleep status of all subjects was assessed using the standard Pittsburgh Sleep Quality Index (PSQI). Hypertension was defined as blood pressure ≥140/90 mmHg in the current study.

RESULTS

After adjusting for basic cardiovascular characteristics, the results of multivariate logistic regression indicated that sleep status, which was defined as the additive measurement of sleep duration and sleep quality, was associated with hypertension prevalence in males of both age groups (odds ratio (OR) = 1.11, 95% confidence interval (CI), 1.07-1.15, p < 0.05; OR = 1.12, 95% CI, 1.08-1.15, p < 0.05) and in females aged ≤45years (OR = 1.10, 95% CI, 1.02-1.18, p < 0.05). As one component of PSQI, short sleep duration was associated with hypertension prevalence only in Chinese male subjects, but this association disappeared after the further adjustment of the other components of PSQI that measured the qualitative aspect of sleep.

CONCLUSION

Association between sleep status and hypertension prevalence in Chinese adults varied by age and sex. Sleep should be measured qualitatively and quantitatively when investigating its association with hypertension.

The Association between Sleep Duration and Non-Alcoholic Fatty Liver Disease among Japanese Men and Women

OBJECTIVE

To examine the relationship between sleep duration and non-alcoholic fatty liver disease (NAFLD).

METHODS

We evaluated 3,968 subjects who underwent health check-ups from June 2012 to May 2013 at the Watari Hospital Health Center in Fukushima Prefecture in Japan. Fatty liver was detected by ultrasonography. Sleep duration and lifestyle factors were estimated using a questionnaire. Sleep duration was categorized into the following groups: ≤ 6, 6 to ≤ 7, >7 to ≤ 8, and >8 h. The four sleep duration groups were compared using the χ(2) test and Kruskal-Wallis test.

RESULTS

In total, 2,172 subjects were enrolled. The overall prevalence of NAFLD was 29.6% (men, 38.0%; women, 25.3%). The proportion of NAFLD tended to decrease as sleep duration increased in men. The proportion with NAFLD was lowest in the group with a sleep duration of 6 to ≤ 7 h and highest in the groups with sleep durations of ≤ 6 and >8 h in women. The distribution showed a U-shaped curve. The age-adjusted odds ratio (OR) (95% confidence interval (CI)) for subjects with NAFLD with a sleep duration ≤ 6 h compared to the reference (6 to ≤ 7 h) was 1.44 (1.06-1.96) in women.

CONCLUSION

Sleep shortage tends to be associated with NAFLD in women and may be mediated by body adiposity.

The metabolic burden of sleep loss

In parallel with the increasing prevalence of obesity and type 2 diabetes, sleep loss has become common in modern societies. An increasing number of epidemiological studies show an association between short sleep duration, sleep disturbances, and circadian desynchronisation of sleep with adverse metabolic traits, in particular obesity and type 2 diabetes. Furthermore, experimental studies point to distinct mechanisms by which insufficient sleep adversely affects metabolic health. Changes in the activity of neuroendocrine systems seem to be major mediators of the detrimental metabolic effects of insufficient sleep, through favouring neurobehavioural outcomes such as increased appetite, enhanced sensitivity to food stimuli, and, ultimately, a surplus in energy intake. The effect of curtailed sleep on physical activity and energy expenditure is less clear, but changes are unlikely to outweigh increases in food intake. Although long-term interventional studies proving a cause and effect association are still scarce, sleep loss seems to be an appealing target for the prevention, and probably treatment, of metabolic disease.

Sleep variability and cardiac autonomic modulation in adolescents - Penn State Child Cohort (PSCC) study

OBJECTIVE

To investigate the effects of objectively measured habitual sleep patterns on cardiac autonomic modulation (CAM) in a population-based sample of adolescents.

METHODS

We used data from 421 adolescents who completed the follow-up examination in the Penn State Children Cohort study. CAM was assessed by heart rate (HR) variability (HRV) analysis of beat-to-beat normal R-R intervals from a 39-h electrocardiogram, on a 30-min basis. The HRV indices included frequency domain (HF, LF, and LF/HF ratio), and time domain (SDNN, RMSSD, and heart rate or HR) variables. Actigraphy was used for seven consecutive nights to estimate nightly sleep duration and time in bed. The seven-night mean (SD) of sleep duration and sleep efficiency were used to represent sleep duration, duration variability, sleep efficiency, and efficiency variability, respectively. HF and LF were log-transformed for statistical analysis. Linear mixed-effect models were used to analyze the association between sleep patterns and CAM.

RESULTS

After adjusting for major confounders, increased sleep duration variability and efficiency variability were significantly associated with lower HRV and higher HR during the 39-h, as well as separated by daytime and nighttime. For instance, a 1-h increase in sleep duration variability is associated with -0.14(0.04), -0.12(0.06), and -0.16(0.05) ms(2) decrease in total, daytime, and nighttime HF, respectively. No associations were found between sleep duration, or sleep efficiency and HRV.

CONCLUSION

Higher habitual sleep duration variability and efficiency variability are associated with lower HRV and higher HR, suggesting that an irregular sleep pattern has an adverse impact on CAM, even in healthy adolescents.

Sleep duration and cardiometabolic risk factors among individuals with type 2 diabetes

OBJECTIVE

To examine the association between sleep duration and cardiometabolic risk factors among individuals with recently diagnosed type 2 diabetes (n = 391).

METHODS

Sleep duration was derived using a combination of questionnaire and objective heart rate and movement sensing in the UK ADDITION-Plus study (2002-2007). Adjusted means were estimated for individual cardiometabolic risk factors and clustered cardiometabolic risk (CCMR) by five categories of sleep duration.

RESULTS

We observed a J-shaped association between sleep duration and CCMR - individuals sleeping 7 to <8 h had a significantly better CCMR profile than those sleeping ≥9 h. Independent of physical activity and sedentary time, individuals sleeping 7 to <8 h had lower triacylglycerol (0.62 mmol/l (0.29, 1.06)) and higher high-density lipoprotein (HDL)-cholesterol levels (0.23 mmol/l (0.16, 0.30)) compared with those sleeping ≥9 h, and a lower waist circumference (7.87 cm (6.06, 9.68)) and body mass index (BMI) (3.47 kg/m(2) (2.69, 4.25)) than those sleeping <6 h. Although sleeping 7 to <8 h was associated with lower levels of systolic and diastolic blood pressure, HbA1c, total cholesterol, and low-density lipoprotein (LDL)-cholesterol, these associations were not statistically significant.

CONCLUSIONS

Sleep duration has a J-shaped association with CCMR in individuals with diabetes, independent of potential confounding. Health promotion interventions might highlight the importance of adequate sleep in this high-risk population.

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.

Association between combined lifestyle factors and non-restorative sleep in Japan: a cross-sectional study based on a Japanese health database

BACKGROUND

Although lifestyle factors such as cigarette smoking, excessive drinking, obesity, low or no exercise, and unhealthy dietary habits have each been associated with inadequate sleep, little is known about their combined effect. The aim of this study was to quantify the overall impact of lifestyle-related factors on non-restorative sleep in the general Japanese population.

METHODS AND FINDINGS

A cross-sectional study of 243,767 participants (men, 39.8%) was performed using the Specific Health Check and Guidance System in Japan. A healthy lifestyle score was calculated by adding up the number of low-risk lifestyle factors for each participant. Low risk was defined as (1) not smoking, (2) body mass index<25 kg/m², (3) moderate or less alcohol consumption, (4) regular exercise, and (5) better eating patterns. Logistic regression analysis was used to examine the relationship between the score and the prevalence of non-restorative sleep, which was determined from questionnaire responses. Among 97,062 men (mean age, 63.9 years) and 146,705 women (mean age, 63.7 years), 18,678 (19.2%) and 38,539 (26.3%) reported non-restorative sleep, respectively. The prevalence of non-restorative sleep decreased with age for both sexes. Compared to participants with a healthy lifestyle score of 5 (most healthy), those with a score of 0 (least healthy) had a higher prevalence of non-restorative sleep (odds ratio, 1.59 [95% confidence interval, 1.29-1.97] for men and 2.88 [1.74-4.76] for women), independently of hypertension, hypercholesterolemia, diabetes, and chronic kidney disease. The main limitation of the study was the cross-sectional design, which limited causal inferences for the identified associations.

CONCLUSIONS

A combination of several unhealthy lifestyle factors was associated with non-restorative sleep among the general Japanese population. Further studies are needed to establish whether general lifestyle modification improves restorative sleep.

Hawthorne effect with transient behavioral and biochemical changes in a randomized controlled sleep extension trial of chronically short-sleeping obese adults: implications for the design and interpretation of clinical studies

OBJECTIVE

To evaluate the effects of study participation per se at the beginning of a sleep extension trial between screening, randomization, and the run-in visit.

DESIGN

Subjects were screened, returned for randomization (Comparison vs. Intervention) after 81 days (median), and attended run-in visit 121 days later.

SETTING

Outpatient.

PATIENTS

Obese (N = 125; M/F, 30/95; Blacks/Whites/Other, N = 73/44/8), mean weight 107.6±19.7 kg, <6.5 h sleep/night.

INTERVENTION

Non-pharmacological sleep extension.

MEASUREMENTS

Sleep duration (diaries and actigraphy watch), sleep quality (Pittsburgh Sleep Quality Index), daily sleepiness (Epworth Sleepiness Scale), fasting glucose, insulin and lipids.

RESULTS

Prior to any intervention, marked improvements occurred between screening and randomization. Sleep duration increased (diaries: 357.4 ±51.2 vs. 388.1±48.6 min/night; mean±SD; P<0.001 screening vs. randomization; actigraphy: 344.3 ±41.9 vs. 358.6±48.2 min/night; P<0.001) sleep quality improved (9.1±3.2 vs. 8.2±3.0 PSQI score; P<0.001), sleepiness tended to improve (8.9±4.6 vs. 8.3±4.5 ESS score; P = 0.06), insulin resistance decreased (0.327±0.038 vs. 0.351±0.045; Quicki index; P<0.001), and lipids improved, except for HDL-C. Abnormal fasting glucose (25% vs. 11%; P = 0.007), and metabolic syndrome (42% vs. 29%; P = 0.007) both decreased. In absence of intervention, the earlier metabolic improvements disappeared at the run-in visit.

LIMITATIONS

Relatively small sample size.

CONCLUSIONS

Improvements in biochemical and behavioral parameters between screening and randomization changed the "true" study baseline, thereby potentially affecting outcome. While regression to the mean and placebo effect were considered, these findings are most consistent with the "Hawthorne effect", according to which behavior measured in the setting of an experimental study changes in response to the attention received from study investigators. This is the first time that biochemical changes were documented with respect to the Hawthorne effect. The findings have implications for the design and conduct of clinical research.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00261898.

Sleep duration and the risk of future lipid profile abnormalities in middle-aged men: the Kansai Healthcare Study

BACKGROUND

Although short sleep duration has been reported to be associated with future cardiometabolic diseases, it is not fully understood whether sleep duration is prospectively associated with the risk of each lipid profile abnormality.

METHODS

Subjects were nondiabetic Japanese, 40-55 years of age, who were not taking oral lipid-lowering medications: for the incidence of low high-density lipoprotein cholesterol (HDL-C), 7627 men with an HDL-C level ≥ 40 mg/dL; for high triglycerides, 6973 men with a triglyceride level <200 mg/dL; for high low-density lipoprotein cholesterol (LDL-C), 7273 men with an LDL-C level <160 mg/dL; for high non-HDL-C, 7415 men with a non-HDL-C level <190 mg/dL; and for high total cholesterol (TC), 7196 men with a TC level <240 mg/dL. Lipid profile abnormalities were defined according to the Adult Treatment Panel III guidelines of the National Cholesterol Education Program.

RESULTS

During the 6-year observation period, there were 1022 cases of low HDL-C. Multiple-adjusted hazard ratios for low HDL-C were 0.79 (95% confidence interval, 0.64-0.97) for sleep durations of 5 to <7 h and 0.62 (0.46-0.83) for ≥ 7 h compared with <5 h. There were 1473 cases of high triglycerides. Multiple-adjusted hazard ratios for high triglycerides were 0.81 (0.68-0.98) for sleep durations of 5 to <7 h and 0.90 (0.72-1.13) for ≥ 7 h compared with <5 h. However, no association between sleep duration and the risk of future high LDL-C, non-HDL-C, or TC was observed.

CONCLUSIONS

Moderate and/or long sleep durations decreased the risk of future low HDL-C and high triglycerides.

Insomnia and its association with hypertension in a community-based population in China: a cross-sectional study

OBJECTIVE

To investigate the prevalence of hypertension and its association with insomnia in a community-based population in China.

METHODS

A cross-sectional study which recruited 10 054 participants aged ≥18 years was conducted in Beijing. The association between self-reported insomnia and hypertension was determined by multiple logistic regression models. Age, gender, education, obesity, body mass index, physical activity, current smoking, current drinking, work stress, diabetes and dyslipidaemia were adjusted for as confounders. Prevalence ratios (PRs) with corresponding 95% CIs were reported as effect measurements.

RESULTS

The number of subjects with no insomnia, occasional insomnia and frequent insomnia was 7632 (75.9%), 1545 (15.4%) and 877 (8.7%), respectively. The prevalence of hypertension in those with no insomnia, occasional insomnia and frequent insomnia was 37.3%, 43.0% and 48.0%. Compared with subjects with no insomnia, the multivariate adjusted PRs and 95% CIs for those with occasional insomnia and frequent insomnia were 1.01 (0.91 to 1.12) and 0.92 (0.83 to 1.03) for men and 1.08 (1.00 to 1.16) and 1.12 (1.02 to 1.22) for women.

CONCLUSIONS

Self-reported insomnia is associated with a higher risk of hypertension in women.

Relationship between self-reported sleep quality and metabolic syndrome in general population

BACKGROUND

To examine an association between self-reported sleep quality determined by Pittsburgh sleep quality index (PSQI) and metabolic syndrome.

METHODS

This study was designed as cross-sectional study. Participants were 1481 adults aged 20 years and above from general population (549 males and 932 females). We assessed the global sleep quality by PSQI. PSQI consists of 7 elements, i.e. subjective sleep quality, sleep latency (prolonged sleep onset time), sleep duration, habitual sleep efficiency (proportion of hours slept to hours spent in bed), sleep disturbance (interruption of sleep), use of sleep medication and daytime dysfunction (trouble staying awake while engaging in social activity). Any participants with score of 6 or more are diagnosed to have sleep disorder. We also assessed the above 7 elements, which consisted of a four-grade system (i.e. 0, 1, 2, 3). Metabolic syndrome consisted of abdominal obesity, hypertension, impaired glucose tolerance and dyslipidemia. Diagnosis of metabolic syndrome was done when the participants have abdominal obesity and meet two or more other components. All analyses were adjusted by age, drinking habit, smoking habit, working hours, exercise habit and depression.

RESULTS

Fifty-two male participants (9.5%) and 133 female (14.3%) scored 6 or more points in global PSQI score. The global PSQI score, sleep latency score and sleep disturbance score of participants with metabolic syndrome were higher level than those without the condition (p < 0.001, p = 0.009, p = 0.025 for male and p < 0.001, p < 0.001, p = 0.002 for females, respectively). The odds ratio of metabolic syndrome among participants with PSQI score of 6 or more points were 2.37 (95% confidence interval: 1.23-4.58) for males and 2.71 (1.45-5.07) for females in contrast to those with 5 or less points. The odds ratio of metabolic syndrome with sleep latency score of 2 was 2.65 (1.14-6.15) for male and 3.82 (1.81-8.09) for females in contrast with those of 0. The odds ratio of metabolic syndrome with sleep disturbance score of 1 was 1.76 (1.09-2.86) for males and 2.43 (1.26-4.69) for females in contrast with those of 0.

CONCLUSIONS

Global PSQI score and its components (especially, sleep latency and sleep disturbance) were associated with metabolic syndrome.

Type 2 diabetes and cardiovascular disease: what next?

PURPOSE OF REVIEW

Cardiovascular disease (CVD) is the leading cause of mortality in type 2 diabetes mellitus (T2DM), and modifying cardiovascular risk through lifestyle intervention and pharmacologic therapy is paramount. This review focuses on recent advances in treatment of classical (traditional) cardiovascular risk factors and highlights the impact of novel risk factors, including sleep disorders, socioeconomic status and chronic psychological stress on CVD in T2DM.

RECENT FINDINGS

Obesity is a substantial cardiovascular risk factor, and recently, large trials of lifestyle and surgical (e.g. gastric bypass) interventions impact on CVD in overweight and obese patients have been reported. Lifestyle intervention including low calorie diet and exercise reduced individual cardiovascular risk factors but did not decrease the rate of long-term cardiovascular events. Bariatric surgery was beneficial in reducing cardiovascular risk factors and long-term cardiovascular events. Sleep insufficiency, poor sleep quality and obstructive sleep apnoea lead to higher CVD and further research is needed to characterize the benefit of treating sleep disorders on long-term cardiovascular events in T2DM. Lastly, socioeconomic status and chronic psychological stress independently have a major impact on increasing CVD in T2DM, and public health policies to reduce this burden will be important to address over the coming decade.

SUMMARY

CVD in T2DM is multifactorial and requires a multifaceted approach in reducing known cardiovascular risks at the individual patient level through lifestyle, pharmacotherapy and surgical interventions and at the societal level through public health policies that support reduction in classical and novel cardiovascular risk factors.

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.

The effect of exercise training on quality and quantity of sleep and lipid profile in renal transplant patients: a randomized clinical trial

BACKGROUND

Patients undergoing renal transplantation consume immunosuppressive drugs to prevent graft rejection. Cardiovascular complications and reduced quality of sleep are among the side effects of these drugs. Studies have indicated that the use of non-therapeutic methods such as exercise is important to reduce these complications.

OBJECTIVE

To evaluate the effect of a period of exercise training, as a non-therapeutic method, on quality and quantity of sleep and lipid profile in renal transplant patients.

METHODS

44 renal transplant recipients were selected to participate in the study and randomized into exercise (n=29) and control (n=15) groups. The exercise group participated in a cumulative exercise program 3 days a week for 10 weeks in 60-90-minute exercise sessions. Control group subjects did not participate in any regular exercise activity during this period. Sleep quality of the subjects was evaluated using Pittsburgh Sleep Quality Index (PSQI) questionnaire; the sleep quantity was assessed by recording the duration of convenient nocturnal sleep of the subjects. Physiological sleep-related variables (serum triglyceride [TG], and total, high-density lipoprotein [HDL], and low-density lipoprotein [LDL] cholesterol) were measured before and after 10 weeks of exercise training

RESULTS

In exercise training group, sleep quality of the subjects was improved by 27%; the sleep quantity was increased by 30 minutes (p<0.05). TG, cholesterol and LDL values were significantly (p<0.05) decreased after 10 weeks of exercise training in the exercise group compared to the control group, however, no change was observed in serum HDL level in exercise group compared to the control. There was also a significant (p=0.05) difference in sleep quality and quantity between control and exercise groups. However, there was no correlation between changing quality and quantity of sleep with sleep-related physiological factors.

CONCLUSION

10 weeks of exercise activity improved the quality and quantity of sleep as well as a number of sleep-related physiological parameters in renal transplant recipients, and would be an effective approach to treat sleep-related disorders in renal transplant recipients.

No effects of short-term sleep restriction, in a controlled feeding setting, on lipid profiles in normal-weight adults

Short sleep has been associated with cardiovascular risk. The aim of this study was to determine the impact of short-term sleep restriction on lipid profiles and resting blood pressure factors in young, normal-weight individuals (14 men, 13 women). Participants were randomized to five nights of either habitual (9 h) or short (4 h) sleep in a cross-over design separated by a 3-week washout period. There was no sleep × day interaction on lipid profile and blood pressure. Short-term sleep restriction does not alter lipid profiles and resting blood pressure in healthy, normal-weight individuals. The association between short sleep and increased cardiovascular risk reported in the epidemiological literature may be the result of long-term sleep restriction and poor lifestyle choices.

Longitudinal associations between objective sleep and lipids: the CARDIA study

STUDY OBJECTIVE

To investigate the longitudinal relationships between actigraph-derived sleep duration, fragmentation, and lipid levels.

DESIGN AND SETTING

Longitudinal data from the Coronary Artery Risk Development in Young Adults Sleep Study (2003-05), an observational cohort at the Chicago site.

PARTICIPANTS

There were 503 black and white adults, ages 32-51 years, with no prior history of cardiovascular disease.

INTERVENTIONS

N/A.

MEASUREMENT AND RESULTS

Sleep duration and fragmentation were measured using 6 days of wrist actigraphy. Sleep quality was measured with the Pittsburgh Sleep Quality Index. The outcome variables, measured at 3 examinations over 10 years (Baseline [2000-01], 5-year [2005-06], and 10-year follow-up [2010-11]), were total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TG), and TC/HDL ratio. The associations between each sleep parameter and 10-year change in lipids were analyzed with generalized estimating equation models adjusting for relevant confounders. After adjustment, each hour increase in sleep duration was significantly associated with higher TC (5.2 mg/dL, 95%CI: 1.7, 8.6) and LDL (3.4 mg/dL, 95%CI: 0.2, 6.6) in the total sample, a 1.1 mg/dL increase in TG (95%CI: 1.0, 1.1) among men, and a borderline significant greater odds for a TC/HDL ratio ≥ 5 among men (OR: 1.37, 95%CI: 0.99, 1.90). Overall, sleep fragmentation and sleep quality scores were not associated with change in lipids.

CONCLUSIONS

Beyond relevant covariates, over a 10-year follow-up, longer objective sleep duration was longitudinally and significantly associated with a poorer lipid profile. Greater objective sleep fragmentation and self-reported poor sleep quality were not related to a poorer lipid profile.

Obstructive sleep apnea and metabolic syndrome in spanish population

Obstructive sleep apnea (OSA) is a clinical picture characterized by repeated episodes of obstruction of the upper airway. OSA is associated with cardiovascular risk factors, some of which are components of metabolic syndrome (MS).

OBJECTIVES

First, determine the prevalence of MS in patients with OSA visited in sleep clinic. Second, evaluate whether there is an independent association between MS components and the severity of OSA.

METHODS

Patients with clinical suspicion of OSA were evaluated by polysomnography. Three groups were defined according to apnea hypoapnea index (AHI): no OSA (AHI <5), mild-moderate (AHI≥ 5 ≤30), and severe (AHI> 30). All patients were determined in fasting blood glucose, total cholesterol, HDL cholesterol, triglycerides and insulin. MS was defined according to criteria of National Cholesterol Education Program (NCEP).

RESULTS

A total of 141 patients (mean age 54 ± 11 years) were evaluated. According to AIH, 25 subjects had no OSA and 116 had OSA (41mild-moderate and 75 severe). MS prevalence ranged from 43-81% in OSA group. Also, a significant increase in waist circumference, triglycerides, glucose, blood pressure levels, and a decrease in HDL cholesterol levels was observed in more severe OSA patients. All polysomnographic parameters correlated significantly with metabolic abnormalities. After a multiple regression analysis, abdominal obesity (p <0.02), glucose (p <0.01) and HDL cholesterol (p <0.001) were independently associated with OSA.

CONCLUSIONS

Our findings show high prevalence of MS in OSA, especially in severe group. A significant association between OSA and some of the components of MS was found in Spanish population.

[Sleep duration among school-age children in Hungary and Romania]

INTRODUCTION

Children's sleep duration is decreasing in the last decade. Despite of the well known negative consequences, there are no data on children's sleep duration in Hungary and Romania.

AIM

The aim of the authors was to assess sleep duration of school-age children in Hungary and Romania.

METHOD

A self-edited questionnaire was used for the study. 2446 children were enrolled. All elementary and secondary schools in a Hungarian city, and one elementary and secondary school in a Romanian city took part in the study.

RESULTS

Mean sleep duration was 8.3 ± 1.2 hours on weekdays. There was a significant difference between the two countries (Hungary vs. Romania, 8.5 ± 1.2 hours vs. 7.8 ± 0.9 hours, p = 0.001). Age correlated with sleep duration on weekdays (r= -0.605, p = 0.001), but not during weekend.

CONCLUSIONS

This is the first study on children's sleep duration in Hungary and Romania. The difference between countries may be due to the difference in mean age or cultural and/or geographical differences.

Associations between sleep duration and prevalence of cardiovascular events

BACKGROUND

Data regarding the associations between sleep duration and clinical cardiovascular (CV) events are limited. We aimed to analyze any associations between self-reported sleep duration and CV events.

HYPOTHESIS METHODS

This is a cross-sectional analysis of nationally representative population of noninstitutionalized US civilians recruited in the 2007 to 2008 National Health and Nutrition Examination Survey. This is a questionnaire-based study including only those subjects who answered questions on sleep duration and CV events. The main outcome measures were prevalence of congestive heart failure, myocardial infarction, stroke, coronary artery disease, and angina.

RESULTS

After logistic regression analysis, significant associations between sleep duration and prevalence of stroke, myocardial infarction, congestive heart failure, coronary artery disease, and angina were found. There was a statistically significant increase in stroke in those with <6 hours of sleep (odds ratio [OR]: 2.0111, 95% confidence interval [CI]: 1.4356-2.8174), in myocardial infarction in those with <6 hours of sleep (OR: 2.0489, 95% CI: 1.4878-2.8216), in congestive heart failure in those with <6 hours of sleep (OR: 1.6702, 95% CI: 1.1555 to 2.4142), in coronary artery disease in those with >8 hours of sleep (OR: 1.1914, 95% CI: 1.0712-3.4231), and in angina in those with >8 hours of sleep (OR: 2.0717, 95% CI: 1.0497-4.0887).

CONCLUSIONS

The results of this cross-sectional analysis suggest that sleep duration may be associated with the prevalence of various CV events.

Cardiovascular disease risk in women with migraine

Background

Studies suggest a higher prevalence of unfavourable cardiovascular risk factors amongst migraineurs, but results have been conflicting. The aim of this study was to investigate traditional and newly recognized risk factors as well as other surrogate markers of cardiovascular risk in obese and normal weight women with migraine.

Methods

Fifty-nine adult female probands participated in this case–control study. The sample was divided into normal weight and obese migraineurs and age- and body mass index-matched control groups. The following cardiovascular risk factors were analyzed: serum levels of lipids, fasting glucose, and insulin; insulin resistance; blood pressure; smoking (categorized as current, past or never); Framingham 10-year risk of general cardiovascular disease score; C-reactive protein; family history of cardiovascular disease; physical activity; sleep disturbances; depression; and bioelectrical impedance phase angle. The means of continuous variables were compared using Student’s t-test for independent samples or the Mann–Whitney U-test (for 2 groups) and ANOVA or the Kruskal-Wallis test (for 4 groups) depending on the distribution of data.

Results

All migraineurs were sedentary irrespective of nutritional status. Migraineurs had higher depression scores and shorter sleep duration, and obese migraineurs, in particular, had worse sleep quality scores. Insulin resistance and insulinaemia were associated with obesity, and obese migraineurs had lower HDL-c than normal weight controls and migraineurs. Also, the Framingham risk score was higher in obese migraineurs.

Conclusion

These findings suggest that female migraineurs experience marked inactivity, depression, and some sleep disturbance, that higher insulin resistance and insulinaemia are related to obesity, and that obesity and migraine probably exert overlapping effects on HDL-c levels and Framingham 10-year cardiovascular risk.

Sleep habits, mental health, and the metabolic syndrome in law enforcement officers

OBJECTIVE

To assess the association of sleep characteristics and mental health with the metabolic syndrome (MetS) in law enforcement officers (LEOs).

METHODS

Sleep duration (≤6, >6-<8, ≥8 hours/night), sleep quality ("good," "poor"), mental health (stress, burnout, depression), and MetS components were compared in 106 LEOs.

RESULTS

The prevalence of MetS was 33%. After covariate adjustment including the mental health measures, long sleep duration was associated with MetS (odds ratio = 4.89, 95% confidence interval = 1.32 to 18.13), whereas sleep quality was not. LEOs with short sleep duration or poor sleep quality reported more stress, burnout, and depression symptoms.

CONCLUSIONS

In LEOs, sleep duration is more strongly associated with the occurrence of MetS than sleep quality, independent of mental health. Nevertheless, short sleep duration and poor sleep quality may affect mental health in LEOs.

Chronic moderate sleep restriction in older long sleepers and older average duration sleepers: a randomized controlled trial

Epidemiologic studies have consistently shown that sleeping <7 h and ≥8 h is associated with increased mortality and morbidity. The risks of short sleep may be consistent with results from experimental sleep deprivation studies. However, there has been little study of chronic moderate sleep restriction and little evaluation of older adults who might be more vulnerable to negative effects of sleep restriction, given their age-related morbidities. Moreover, the risks of long sleep have scarcely been examined experimentally. Moderate sleep restriction might benefit older long sleepers who often spend excessive time in bed (TIB) in contrast to older adults with average sleep patterns. Our aims are: (1) to examine the ability of older long sleepers and older average sleepers to adhere to 60 min TIB restriction; and (2) to contrast effects of chronic TIB restriction in older long vs. average sleepers. Older adults (n = 100) (60-80 years) who sleep 8-9 h per night and 100 older adults who sleep 6-7.25 h per night will be examined at 4 sites over 5 years. Following a 2-week baseline, participants will be randomized to one of two 12-week treatments: (1) a sleep restriction involving a fixed sleep-wake schedule, in which TIB is reduced 60 min below each participant's baseline TIB; and (2) a control treatment involving no sleep restriction, but a fixed sleep schedule. Sleep will be assessed with actigraphy and a diary. Measures will include glucose tolerance, sleepiness, depressive symptoms, quality of life, cognitive performance, incidence of illness or accident, and inflammation.

Therapeutic efficacy and anti-inflammatory effect of ramelteon in patients with insomnia associated with lower urinary tract symptoms

OBJECTIVES

This study was conducted to examine the therapeutic efficacy and anti-inflammatory effect of ramelteon in elderly patients with insomnia associated with lower urinary tract symptoms (LUTS), who visited our urology department.

METHODS

The study included 115 patients (102 men, 13 women) who scored ≥4 on the Athens Insomnia Scale and who wished to receive treatment. The assessment scales for therapeutic efficacy included the International Prostate Symptom Score (IPSS) for LUTS and the Insomnia Severity Index (ISI) for sleep disorders. The high-sensitivity C-reactive protein (hs-CRP) test was used to an objective assessment. The patients were treated with ramelteon (8 mg/day) for an average of 10 weeks and were then reexamined using the questionnaires and hs-CRP test to evaluate therapeutic efficacy.

RESULTS

IPSS total scores declined significantly from 11.39 ± 8.78 to 9.4 ± 7.72. ISI total scores improved significantly from 11.6 ± 5.2 to 9.2 ± 5.3 (P < 0.0001). The levels of hs-CRP decreased significantly from 0.082 (standard deviation [SD] upper limit, 0.222; SD lower limit, -0.059) to 0.06 (SD upper limit, 0.152; SD lower limit, -0.032). The ISI scores ≥ 10 (n = 51) showed a weak correlation with the hs-CRP levels.

CONCLUSION

Ramelteon had a systemic anti-inflammatory effect and improved sleep disorders and LUTS, suggesting that it may be a useful treatment for patients with LUTS-associated insomnia.

Sleep, type 2 diabetes, dyslipidemia, and hypertension in elderly Alzheimer's caregivers

Research indicates that very short or long durations of sleep and inefficient sleep are associated with higher total cholesterol and risk of type 2 diabetes and hypertension. This study tested the hypothesis that inefficient sleep or short/long sleep durations are associated with an elevated prevalence of type 2 diabetes, dyslipidemia, and hypertension in a community-dwelling sample of elderly Alzheimer's caregivers. Participants were 126 caregivers for spouses with Alzheimer's disease who underwent in-home sleep assessment by wrist actigraphy for 72 consecutive hours. Sleep data were averaged across the 3 days/nights; nighttime sleep and daytime napping were computed. Morning fasting blood samples were collected to determine measures of blood lipids and glucose. The average of three resting blood pressure measurements was used to estimate mean resting blood pressure. Logistic regression models including covariates related to sleep and metabolic regulation indicated that nighttime sleep duration, percent sleep at night, and daytime naps were not significantly associated with odds of having diabetes (OR, 0.92; 95% CI, 0.56-1.53; OR, 0.93; 95% CI, 0.83-1.03; OR, 1.75; 95% CI, 0.74-4.11, respectively), dyslipidemia (OR, 0.83; 95% CI, 0.57-1.20; OR, 0.99; 95% CI, 0.92-1.07; OR, 0.64; 95% CI, 0.33-1.24, respectively), or hypertension (OR, 0.97; 95%CI, 0.62-1.52; OR, 1.02; 95% CI, 0.93-1.11; OR, 1.10; 95% CI, 0.44-2.74, respectively). When categorical and combined sleep parameters were examined, there were no significant associations with any of the metabolic conditions (all p>0.05). The current study suggests that in an elderly sample of Alzheimer's caregivers, nighttime sleep duration, nighttime sleep efficiency and daytime naps are not significantly associated with prevalent type 2 diabetes, dyslipidemia, or hypertension. As several of the associations demonstrated clinically relevant magnitudes of the associations, larger studies to more fully test these hypotheses are warranted.

Association between Sleep Disruption and Levels of Lipids in Caucasians with Type 2 Diabetes

Aim. To investigate the association between sleep quality and duration with lipid and glycaemic control in Caucasian subjects with type 2 diabetes. Methods. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) in 114 type 2 diabetes (T2DM) subjects. Comparisons were made between subjects with different sleep quality and sleep duration. Hierarchical multiple regression analyses were used to determine contributors to metabolic parameters. Results. Subjects with poor sleep quality (PQ; PSQI ≥ 6) had higher systolic blood pressure, glycated haemoglobin, urine albumin : creatinine ratio (UAC), total cholesterol (TC), and triglycerides (TG) (P < 0.05 for all) compared to those with good sleep quality (GQ; PSQI ≤ 5). Long sleep duration (LSD) subjects had higher TC and short sleep duration (SSD) subjects had higher TG compared to those with medium sleep duration. Sleep duration and PSQI score were independent predictors of TC and low-density lipoprotein cholesterol (LDL), contributing to 14.0% and 6.1% of the total variance, respectively. Conclusions. In this Caucasian T2DM population, PQ is associated with adverse cardiovascular risk markers, and long and short sleep disruptions have an independent negative impact on lipids. Sleep assessment should be included as part of a diabetes clinic review.

Survey on lower urinary tract symptoms and sleep disorders in patients treated at urology departments

OBJECTIVES

This study examined the association between sleep disorders and lower urinary tract symptoms in patients who had visited urology departments.

METHODS

This was an independent cross-sectional, observational study. Outpatients who had visited the urology departments at the Kinki University School of Medicine or the Sakai Hospital, Kinki University School of Medicine, between August 2011 and January 2012 were assessed using the Athens Insomnia Scale and the International Prostate Symptom Score.

RESULTS

In total, 1174 patients (mean age, 65.7 ± 13.7 years), with 895 men (67.1 ± 13.2 years old) and 279 women (61.4 ± 14.6 years old), were included in the study. Approximately half of these patients were suspected of having a sleep disorder. With regard to the International Prostate Symptom Score subscores, a significant increase in the risk for suspected sleep disorders was observed among patients with a post-micturition symptom (the feeling of incomplete emptying) subscore of ≥1 (a 2.3-fold increase), a storage symptom (daytime frequency + urgency + nocturia) subscore of ≥5 (a 2.7-fold increase), a voiding symptom (intermittency + slow stream + hesitancy) subscore of ≥2 (a 2.6-fold increase), and a nocturia subscore of ≥2 (a 1.9-fold increase).

CONCLUSION

The results demonstrated that the risk factors for sleep disorders could also include voiding, post-micturition, and storage symptoms, in addition to nocturia.

Sleep duration is associated with dyslipidemia in patients with bipolar disorder in clinical remission

BACKGROUND

The pathways to increased cardiovascular risk in bipolar disorder include health behaviors, psychosocial stress and long-term medication exposure. However, the evidence that the association between cardiovascular risk factors and bipolar disorder remains significant after controlling for these co-factors suggests that additional important risk factors have yet to be identified. Our hypothesis is that disturbances in the sleep-wake cycle are an important and under-recognized pathway through which affective disorders lead to increased cardiovascular risk.

METHODS

In patients with bipolar disorder type 1 in clinical remission, we: 1) explored whether sleep disturbance predicted the endorsement of NCEP ATP-III criteria for dyslipidemia, independent of other lifestyle factors and 2) tested the association between low HDL (NCEP-ATP III) and sleep duration measured with actigraphy over an eight-day period.

RESULTS

Median sleep duration is significantly associated with low HDL. The risk of having low HDL increases by 1.23 with every 30 minutes of reduced sleep time.

LIMITATIONS

Since sleep patterns in patients with bipolar disorder are variable and irregular, it is possible that other sleep characteristics, not present during the span of our study, or the variability itself may be what drives the increased cardiovascular risk.

CONCLUSIONS

Sleep characteristics of patients with bipolar disorder in clinical remission are associated with cardiovascular risk. More specifically, sleep duration was associated with low HDL. Clinicians should pay special attention to sleep hygiene in treating individuals with bipolar disorder, even when they are in clinical remission.

Association of insomnia and short sleep duration with atherosclerosis risk in the elderly

BACKGROUND

Short sleep duration is associated with an increased risk of cardiovascular disease and all-cause mortality, although a relationship with atherosclerosis in the elderly remains unclear.

METHODS

Eighty-six volunteers aged ≥65 years (mean, 73.6 ± 4.9 years) were evaluated for insomnia. Total sleep time (TST) and sleep efficiency were measured by actigraphy. Subjective symptoms were assessed with the Pittsburgh Sleep Quality Index (PSQI). Atherosclerosis was evaluated using ultrasonographic measurements of carotid intima-media thickness (IMT).

RESULTS

IMT was significantly greater and sleep efficiency was significantly lower in subjects with TST ≤5 h than those with TST >7 h (1.3 ± 0.5 vs. 0.9 ± 0.3 mm; P = 0.009; 91.0 ± 6.0 vs. 81.6 ± 11.3%, P = 0.03, respectively). IMT was also significantly greater in the insomnia group than the noninsomnia group (1.3 ± 0.5 vs. 1.1 ± 0.4 mm; P = 0.03). IMT was significantly correlated with systolic blood pressure (SBP), diastolic blood pressure (DBP), and TST (SBP: r = 0.49, P < 0.0001; DBP: r = 0.33, P = 0.0021; TST: r = -0.28, P = 0.010). Multiple regression analysis revealed that SBP, TST, and the PSQI were significant contributing factors for increased IMT (SBP: coefficient β = 0.56, P = 0.0001; TST: coefficient β = -0.32, P = 0.005; PSQI: coefficient β = 0.22, P = 0.05).

CONCLUSIONS

High blood pressure, short sleep duration (≤5 h), poor sleep, and insomnia were associated with atherosclerosis risk leading to cardiovascular disease in the elderly.

Metabolic effects of chronic sleep restriction in rats

STUDY OBJECTIVES

Chronic partial sleep loss is associated with obesity and metabolic syndrome in humans. We used rats with lesions in the ventrolateral preoptic area (VLPO), which spontaneously sleep about 30% less than intact rats, as an animal model to study the consequences of chronic partial sleep loss on energy metabolism.

PARTICIPANTS

Adult male Sprague-Dawley rats (300-365 g).

INTERVENTIONS

We ablated the VLPO in rats using orexin-B-saporin and instrumented them with electrodes for sleep recordings. We monitored their food intake and body weight for the next 60 days and assessed their sleep-wake by 24-h EEG/EMG recordings on day 20 and day 50 post-surgery. On day 60, after blood samples were collected for metabolic profiling, the animals were euthanized and the brains were harvested for histological confirmation of the lesion site.

MEASUREMENTS AND RESULTS

VLPO-lesioned animals slept up to 40% less than sham-lesioned rats. However, they showed slower weight gain than sham-lesioned controls, despite having normal food intake. An increase in plasma ghrelin and a decrease in leptin levels were observed, whereas plasma insulin levels remained unaffected. As expected from leaner animals, plasma levels of glucose, cholesterol, triglycerides, and C-reactive protein were reduced in VLPO-lesioned animals.

CONCLUSIONS

Chronic partial sleep loss did not lead to obesity or metabolic syndrome in rats. This finding raises the question whether adverse metabolic outcomes associated with chronic partial sleep loss in humans may be due to factors other than short sleep, such as circadian disruption, inactivity, or diet during the additional waking hours.

Short sleep duration associated with a higher prevalence of metabolic syndrome in an apparently healthy population

OBJECTIVE

To examine the association between sleep duration and metabolic syndrome in an apparently healthy Chinese population.

METHOD

The baseline data were collected from a health examination center in Tainan, Taiwan, from October 1, 2006, to August 31, 2009. A total of 7100 adults were recruited. Subjects were classified into three groups according to their sleep duration: short (<6 h), normal (6-8 h), and long sleepers (>8 h).

RESULTS

There were significant differences in age, gender, education level, fasting plasma glucose, and the proportion of smoking status and exercise frequency among different sleep groups. Based on multiple logistic regression, short sleepers were positively associated with metabolic syndrome (OR=1.28, 95% CI: 1.01-1.63) in males but not in females (OR=1.04, 95% CI: 0.72-1.51). Long sleepers were not related with metabolic syndrome in both genders. Short sleep duration was independently related to hyperglycemia (OR=1.39, 95% CI: 1.10-1.74) also in males only. Other components such as hypertriglyceridemia, low high density lipoprotein cholesterol, high blood pressure and central obesity were not associated with short sleep duration.

CONCLUSION

Males with short sleep duration are positively associated with metabolic syndrome and they also exhibited a higher prevalence of hyperglycemia.

Sleep disturbance and cardiovascular risk in adolescents

BACKGROUND

Evidence suggests that inadequate or disturbed sleep is associated with increased cardiovascular risk in adults. There are limited data on sleep quality and associated cardiovascular risk in children.

METHODS

We obtained data on adolescents from the 2009/10 cycle of the Healthy Heart Schools' Program, a population-based cross-sectional study in the Niagara region of Ontario. Participants underwent measurements of cardiometabolic risk factors, including body mass index (BMI), lipid profile and blood pressure, and they completed questionnaires measuring sleeping habits and nutritional status. We assessed sleep disturbance using the sleep disturbance score derived from the Pittsburgh Sleep Quality Index. We explored associations between sleeping habits and cardiovascular risk factors.

RESULTS

Among 4104 adolescents (51% male), the mean hours of sleep per night (± standard deviation) were 7.9 ± 1.1 on weeknights and 9.4 ± 1.6 on weekends. In total, 19% of participants reported their sleep quality as fairly bad or very bad on weeknights and 10% reported it as fairly bad or very bad on weekends. In the multivariable regression models, a higher sleep disturbance score was associated with increased odds of being at high cardiovascular risk (highest v. lowest tertile odds ratio [OR] 1.43 [95% confidence interval (CI) 1.16-1.77], p < 0.001), increased odds of hypertension (highest v. lowest tertile OR 1.44 [95% CI 1.02-2.05], p = 0.05) and increased odds of elevated non-high density lipoprotein cholesterol (highest v. lowest tertile OR 1.28 [95% CI 1.00-1.64], p = 0.05). The mean duration of sleep was not associated with these outcomes.

INTERPRETATION

In healthy adolescents, sleep disturbance is associated with cardiovascular risk factor abnormalities. Intervention strategies to optimize sleep hygiene early in life may be important for the prevention of cardiovascular disease.

Sleep duration, snoring habits, and cardiovascular disease risk factors in an ethnically diverse population

BACKGROUND

Lack of sleep has been associated with an increased risk for cardiovascular disease (CVD) and all-cause mortality, but the mechanisms are not fully understood. Prior research has often been conducted in select populations and has not consistently adjusted for confounders, especially psychosocial factors.

OBJECTIVE

The aims of this study were to assess the association between sleep habits and established risk factors for CVD and to evaluate potential interactions by race and gender.

METHODS

Participants were part of a CVD screening and educational outreach program in New York City. Free-living men older than 40 years and women older than 50 years (n = 371, mean age = 60 years, 57% women, 60% racial/ethnic minorities) were systematically assessed for CVD risk (including traditional, lifestyle, and psychosocial risk factors) and completed a standardized questionnaire regarding sleep habits (including sleep duration and snoring). Lipids were analyzed by validated finger-stick technology. Stress at work and at home was assessed using a validated screening tool from the INTERHEART study. Associations between participants' sleep habits and CVD risk factors/demographic factors were assessed using multivariable logistic regression.

RESULTS

The proportion of participants who reported sleeping less than 6 hours per night on average was 28%, and 52% of participants reported snoring. Sleeping less than 6 hours per night was significantly (P < .05) associated with female gender, being single, increased stress at home, increased financial stress, and low-density lipoprotein cholesterol (LDL-C) level. Gender modified the association between sleep duration and LDL-C level (P = .04): Sleeping less than 6 hours per night was significantly associated with reduced LDL-C level among women and increased LDL-C level among men. Snoring was significantly associated with low high-density lipoprotein cholesterol (HDL-C) level (<40 mg/dL for men/<50 mg/dL for women), being married, increased stress at work and at home, less than 30 minutes of exercise per day, less than 5 servings of fruits and vegetables per day, and being overweight/obese (body mass index ≥25 kg/m). The association between snoring and low HDL-C level remained significant in logistic regression models adjusted for demographic confounders (odds ratio, 1.83; 95% confidence interval, 1.06-3.19) but not after adjustment for body mass index greater than 25 kg/m.

CONCLUSIONS

Sleeping less than 6 hours per night was associated with several traditional and psychosocial CVD risk factors, and snoring was associated with low HDL-C level, likely mediated through overweight/obesity. These data may have significance for health care providers to identify individuals who may be at increased CVD risk based on sleep habits.

Association of leisure physical activity and sleep with cardiovascular risk factors in postmenopausal women

OBJECTIVE

The aim of this study was to examine the individual and combined associations of leisure-time physical activity and sleep with cardiovascular risk factors in postmenopausal women.

METHODS

We analyzed 48-month cross-sectional follow-up data from 393 participants of the Women on the Move Through Activity and Nutrition Study, a behavioral weight loss trial. Leisure-time physical activity data were collected with the past-year Modifiable Activity Questionnaire, whereas sleep data were collected with the Pittsburgh Sleep Quality Index. We compared physical activity and sleep categories using analysis of variance, post hoc Scheffe tests, and multivariate analyses based on groups above/below the median leisure-time physical activity level, above/below the sleep quality value of 5, and above/below the sleep duration of 7 hours/day.

RESULTS

The average sleep quality and sleep duration did not significantly differ between women with high and women with low physical activity levels. When women with good sleep quality were compared, higher physical activity levels were associated with lower body mass index (2.0 kg/m; 25, 75 quartiles, 0.3, 3.6), waist circumference (6.3 cm; 1.7, 10.9), and total body fat (2.1%; 0.3, 4.0; P < 0.05). When participants with poor sleep quality were compared, highly active women had lower trunk fat, total body fat, and insulin levels than less active women did (P < 0.05). In multivariate analysis, physical activity was significantly associated with high-density lipoprotein level, trunk fat, and total body fat after controlling for sleep quality, sleep duration, age, hormone therapy and smoking status, and body mass index.

CONCLUSIONS

The combined associations of leisure-time physical activity and sleep suggest that cardiovascular risk factors are more favorable in highly active women relative to less active women regardless of sleep.

Arrhythmia and sleep-disordered breathing in patients undergoing cardiac surgery

BACKGROUND

Recently, the role of sleep-disordered breathing (SDB) in cardiovascular disease has attracted attention. In this study, we investigated the influence of SDB on postoperative arrhythmias after cardiac surgery.

METHODS AND RESULTS

In 89 patients undergoing cardiac surgery, postoperative portable monitoring for SDB and Holter electrocardiography were performed. The primary end-points were the apnea-hypopnea index (AHI) and occurrence of arrhythmia. The secondary end-points were: (1) patient background factors; (2) average heart rate; (3) maximum heart rate (total, daytime, and nighttime); (4) minimum heart rate (total, daytime, and nighttime); (5) minimum SaO(2) during sleep; and (6) an independent predictor for arrhythmia. Twenty-six patients (29.2%) had an AHI≥15 and they were classified into the SDB group, while patients with an AHI<15 formed the non-SDB group (70.8%). Although there was no significant difference in atrial fibrillation, frequent nocturnal premature ventricular contractions were significantly more common in the SDB group (19.2%) than the non-SDB group (3.2%) (p=0.01). Maximum daytime and nighttime heart rates were also significantly higher in the SDB group. AHI was a significant predictor for frequent nocturnal premature ventricular contractions.

CONCLUSIONS

This study showed that SDB is common among patients undergoing cardiac surgery, and that SDB might be closely associated with arrhythmia in these patients.

Insomnia symptoms and cardiovascular disease among older American Indians: the Native Elder Care Study

Background. Cardiovascular disease (CVD) is the leading cause of death among American Indians. It is not known if symptoms of insomnia are associated with CVD in this population. Methods. We examined 449 American Indians aged ≥55 years from the Native Elder Care Study. The main outcome-of-interest was self-reported CVD. Results. Short sleep duration, daytime sleepiness, and difficulty falling asleep were positively associated with CVD after adjusting for demographic, lifestyle, and clinical risk factors. Compared with a sleep duration of 7 h, the multivariable odds ratio (OR) (95% confidence interval [CI]) of CVD among those with sleep duration ≤5 h was 2.89 (1.17–7.16). Similarly, the multivariable OR (95% CI) of CVD was 4.45 (1.85–10.72) and 2.60 (1.25–5.42) for daytime sleepiness >2 h and difficulty falling asleep often/always. Conclusion. Symptoms of insomnia including short sleep duration, daytime sleepiness, and difficulty falling asleep are independently associated with CVD in American Indians aged ≥55 years.

Sleep duration and hypercholesterolaemia: Results from the National Health Interview Survey 2008

BACKGROUND

Previous studies have shown an inconsistent association between sleep duration and hypercholesterolaemia. This study examined the association between sleep duration and hypercholesterolaemia in a nationally representative sample of US adults.

METHODS

A cross-sectional study of 16,652 participants in the 2008 National Health Interview Survey (aged ⩾18years, 52.5% women) was conducted. Sleep duration was categorized as ⩽5, 6, 7, 8, or ⩾9h. Hypercholesterolaemia (n=5578) was assessed by questionnaire.

RESULTS

A significant gender difference was found in the association between sleep duration and hypercholesterolaemia (P interaction=0.003). Among women, sleep duration ⩽5h was positively associated with hypercholesterolaemia after adjusting for potential confounders and mediators including physical activity, psychological distress, body mass index, diabetes mellitus, and hypertension. Compared with a sleep duration of 7h (referent), the multivariate odds ratio (OR) of hypercholesterolaemia was 1.27 (95% confidence interval [CI] 1.04-1.54) for sleep duration ⩽5h. In contrast, among men, sleep duration ⩾8h was inversely associated with hypercholesterolaemia. Compared with a sleep duration of 7h (referent), the multivariate OR of hypercholesterolaemia was 0.80 (95% CI 0.69-0.94) and 0.78 (95% CI 0.60-1.00) for sleep durations of 8 and ⩾9h, respectively. In subgroup analyses, the positive association between sleep duration ⩽5h and hypercholesterolaemia in women, and the inverse association between sleep duration ⩾8h and hypercholesterolaemia in men, were more pronounced among those aged <60 years and race/ethnic groups other than non-Hispanic Whites.

CONCLUSION

Sleep duration ⩽5h was positively associated with hypercholesterolaemia in women, whereas sleep duration ⩾8h was inversely associated with hypercholesterolaemia in men.

Associations of sleep duration with obesity and serum lipid profile in children and adolescents

INTRODUCTION

The association between sleep duration, obesity, and serum lipid profile in the youth population is under-explored.

OBJECTIVE

To evaluate the association between sleep duration, obesity and serum lipid profile in the youth population.

METHODS

We conducted a cross-sectional population-based study with students recruited from primary and secondary schools in Hong Kong. Anthropometric measurements, fasting lipid profiles and validated questionnaires on sleep duration were performed. A subgroup (n=138) was randomly selected for both questionnaires and actigraphy to assess the agreement between subjective and objective measurements of sleep duration.

RESULTS

We studied 2053 healthy children and adolescents aged 6-20 years. Their mean ages were 13.0±3.3 (boys) and 13.6±3.3 (girls) years. The average sleep duration during schooldays, weekends, and long holidays was 8.0±1.1, 9.6±1.2, and 9.8±1.2h in boys and 7.7±1.1, 9.9±1.2, and 10.1±1.2h in girls, respectively. Using logistic regression, age, and pubertal stage were associated with obesity in secondary school students, whereas male gender and short sleep duration were associated with obesity in primary school children. In secondary school children, those with long sleep duration, as compared to those with short sleep duration, were significantly associated with reduced risk to have high TC and LDL-C levels after adjustment for age, gender, BMI, and pubertal stage. There was no significant association between sleep duration and lipid levels in primary school children.

CONCLUSION

Reduced sleep duration was associated with obesity and atherogenic dyslipidemia in young school children in Hong Kong.

[Quality of sleep and serum lipid profile in patients with restless legs syndrome]

PURPOSE

The purpose of this study was to compare the quality of sleep with the serum lipid profile in patients who have restless legs syndrome (RLS).

METHODS

The data were obtained from 116 patients with RLS through questionnaires and blood sampling.

RESULTS

The results of this study showed correlations between lower quality of sleep and serum lipid profile (LDL Cholesterol) in patients with RLS (r=.19, p=.040). There were correlations for scores of quality of sleep from the, Pittsburgh Sleep Quality Index (PSQI) sub-region between lower subjective sleep quality and serum lipid profile (LDL Cholesterol) (r=.20, p=.026), between fewer hours of sleep duration and serum lipid profile (Total Cholesterol) (r=-.21, p=.024), and, between higher daytime dysfunction and serum lipid profile (LDL Cholesterol) (r=.42, p<.001) of patients with RLS.

CONCLUSION

Patients with RLS have sleep disorders with lower quality of sleep and changes in the serum lipid profile for total cholesterol and LDL cholesterol. That is, patients with RLS have lower quality of sleep and dyslipidemia compared to persons without RLS. Further research is needed to monitor serum the lipid profile in early stage symptoms of midlife adult patients with RLS and especially older women.

Self-reported long total sleep duration is associated with metabolic syndrome: the Guangzhou Biobank Cohort Study

OBJECTIVE

To examine the association between total sleep duration and the prevalence of metabolic syndrome (MetSyn) in older Chinese.

RESEARCH DESIGN AND METHODS

Cross-sectional analysis of baseline data from the Guangzhou Biobank Cohort Study (GBCS) was performed. Participants (n = 29,333) were aged ≥50 years. Risk of MetSyn and its components were identified for self-reported total sleep duration.

RESULTS

Participants reporting long (≥9 h) and short (<6 h) total sleep duration had increased odds ratio (OR) of 1.18 (95% CI 1.07-1.30) and 1.14 (1.05-1.24) for the presence of MetSyn, respectively. The relationship remained in long sleepers (OR 1.21 [1.10-1.34]) but diminished in short sleepers (0.97 [0.88-1.06]) after full adjustment.

CONCLUSIONS

Long sleep duration was associated with greater risk of MetSyn in older Chinese. Confirmation through longitudinal studies is needed. The mechanisms mediating the link between long sleep duration and MetSyn require further investigation.

Metabolic, endocrine, and immune consequences of sleep deprivation

Over the last three to four decades, it has been observed that the average total hours of sleep have decreased to less than seven hours per person per night. Concomitantly, global figures relating to obesity and diabetes mellitus have increased in an alarming fashion in adults and children, and it has been hypothesized that neuro-hormonal changes accompanying this behavioral sleep deprivation may lead to insulin resistance and, subsequently, to diabetes mellitus. Sleep deprivation has been associated with multiple physiological changes, including increased cortisol and ghrelin levels, decreased leptin levels and impaired glucose metabolism. Experimental studies have also shown an increase in inflammatory and pro-inflammatory markers, which are indicators of body stress, under sleep deprivation. This review elaborates further on this hypothesis, exploring the molecular basis for the link between both entities and the underlying pathophysiology that results in insulin resistance and diabetes mellitus. We review the results of experimental and epidemiological studies, specifically examining the relationship between sleep duration and the immune and endocrine systems.