Association of sleep duration and hypertension among US adults varies by age and sex

Potential mechanisms of ischemic stroke induced by heat exposure

Recent decades of epidemiological and clinical research have suggested that heat exposure could be a potential risk factor for ischemic stroke. Despite climate factors having a minor impact on individuals compared with established risk factors such as smoking, their widespread and persistent effects significantly affect public health. The mechanisms by which heat exposure triggers ischemic stroke are currently unclear. However, several potential mechanisms, such as the impact of temperature variability on stroke risk factors, inflammation, oxidative stress, and coagulation system changes, have been proposed. This article details the potential mechanisms by which heat exposure may induce ischemic stroke, aiming to guide the prevention and treatment of high-risk groups in hot climates and support public health policy development.

Sleep Duration and Blood Pressure in Youth Referred for Elevated Blood Pressure Evaluation

OBJECTIVES

Sleep promotion is not specifically recommended as a target for hypertension management. We examined associations of sleep duration and timing with blood pressure parameters in patients referred to pediatric nephrology clinic for elevated blood pressure evaluation.

METHODS

This is a retrospective study of initial ambulatory blood pressure monitoring data and self-report sleep data collected from patients referred to nephrology clinic for the evaluation of elevated blood pressure. Linear and logistic regression modeling determined associations between sleep exposures (duration and timing) and continuous and dichotomous blood pressure outcomes, respectively, adjusted for age, sex, body mass index, and weekday versus weekend status.

RESULTS

The study sample included 539 patients with mean age 14.6 years and 56% meeting hypertension criteria. Sleep duration averaged 9.1 hours per night. Average timing of sleep onset and offset were 11:06 pm and 8:18 am, respectively. Longer sleep duration was associated with better daytime blood pressure parameters (eg, every extra hour of sleep duration was associated with a reduced odds of wake hypertension [odds ratio, 0.88; 95% CI, 0.79-0.99]). Later sleep onset was associated with worse daytime blood pressure parameters (eg, each additional hour of later sleep onset was associated with higher wake systolic blood pressure index [mean wake blood pressure/95th percentile]) (β = 0.07; 95% CI, 0.02-0.13). Associations were consistent across sex, age, body mass index, and weekday status.

CONCLUSIONS

Longer sleep duration and earlier sleep onset were associated with lower blood pressure. This suggests that sleep optimization may be an important target for intervention in hypertension management.

Effect of glucocorticoid blockade on inflammatory responses to acute sleep fragmentation in male mice

The association between sleep and the immune-endocrine system is well recognized, but the nature of that relationship is not well understood. Sleep fragmentation induces a pro-inflammatory response in peripheral tissues and brain, but it also activates the hypothalamic-pituitary-adrenal (HPA) axis, releasing glucocorticoids (GCs) (cortisol in humans and corticosterone in mice). It is unclear whether this rapid release of glucocorticoids acts to potentiate or dampen the inflammatory response in the short term. The purpose of this study was to determine whether blocking or suppressing glucocorticoid activity will affect the inflammatory response from acute sleep fragmentation (ASF). Male C57BL/6J mice were injected i.p. with either 0.9% NaCl (vehicle 1), metyrapone (a glucocorticoid synthesis inhibitor, dissolved in vehicle 1), 2% ethanol in polyethylene glycol (vehicle 2), or mifepristone (a glucocorticoid receptor antagonist, dissolved in vehicle 2) 10 min before the start of ASF or no sleep fragmentation (NSF). After 24 h, samples were collected from brain (prefrontal cortex, hypothalamus, hippocampus) and periphery (liver, spleen, heart, and epididymal white adipose tissue (EWAT)). Proinflammatory gene expression (TNF-α and IL-1β) was measured, followed by gene expression analysis. Metyrapone treatment affected pro-inflammatory cytokine gene expression during ASF in some peripheral tissues, but not in the brain. More specifically, metyrapone treatment suppressed IL-1β expression in EWAT during ASF, which implies a pro-inflammatory effect of GCs. However, in cardiac tissue, metyrapone treatment increased TNF-α expression in ASF mice, suggesting an anti-inflammatory effect of GCs. Mifepristone treatment yielded more significant results than metyrapone, reducing TNF-α expression in liver (only NSF mice) and cardiac tissue during ASF, indicating a pro-inflammatory role. Conversely, in the spleen of ASF-mice, mifepristone increased pro-inflammatory cytokines (TNF-α and IL-1β), demonstrating an anti-inflammatory role. Furthermore, irrespective of sleep fragmentation, mifepristone increased pro-inflammatory cytokine gene expression in heart (IL-1β), pre-frontal cortex (IL-1β), and hypothalamus (IL-1β). The results provide mixed evidence for pro- and anti-inflammatory functions of corticosterone to regulate inflammatory responses to acute sleep loss.

Profiling the socioeconomic characteristics, dietary intake, and health status of Korean older adults for nutrition plan customization: a comparison of principal component, factor, and cluster analyses

OBJECTIVES

This study was conducted to establish profiles of socioeconomic characteristics, dietary intake, and health status among Korean older adults by employing 3 multivariate analysis techniques.

METHODS

Data were obtained from 1,352 adults aged 65 years and older who participated in the 2019 Korea National Health and Nutrition Examination Survey. Principal component analysis (PCA), factor analysis (FA), and cluster analysis (CA) were utilized for profiling, with data preprocessing undertaken to facilitate these approaches.

RESULTS

PCA, FA, and CA yielded similar results, reflecting the high common variance among the variables. PCA identified 4 components, accounting for 71.6% of the accumulated variance. FA revealed 5 factors, displaying a Kaiser-Meyer-Olkin value of 0.51 and explaining 74.3% of the total variance. Finally, CA grouped the participants into 4 clusters (R2=0.465). Both PCA and FA identified dietary intake (energy, protein, carbohydrate, etc.), social support from family (incorporating family structure, number of family numbers, and engagement in social eating), and health status (encompassing oral, physical, and subjective health) as key factors. CA classified Korean older adults into 4 distinct typologies, with significant differences observed in dietary intake, health status, and household income (p<0.01).

CONCLUSIONS

The study utilized PCA, FA, and CA to analyze profiling domains and derive characteristics of older adults in Korea, followed by a comparison of the results. The variables defining the clusters in CA were consistent with those identified by PCA and FA.

Berry Consumption and Sleep in the Adult US General Population: Results from the National Health and Nutrition Examination Survey 2005-2018

INTRODUCTION

Poor sleep is associated with numerous adverse health outcomes. Berries are rich in micronutrients and antioxidants that may improve sleep quality and duration. We determined the association of berry consumption and sleep duration and sleep difficulty among adult participants in NHANES.

METHODS

We analyzed the diet of US adults aged ≥ 20 y using two non-consecutive 24 h recalls from the National Health and Nutrition Examination Survey 2005 to 2018 (N = 29,217). Poor sleep quality was measured by sleep duration (short sleep duration: <7 h), long sleep (≥9 h), and reported sleep difficulty. The relative risk of poor sleep outcomes for berry consumers vs. nonconsumers was modelled using population weight-adjusted multivariable general logistic regression.

RESULTS

About 46% of participants reported inadequate sleep duration, and 27% reported sleep difficulties. Twenty-two percent reported consuming berries. Berry consumers had a 10-17% decreased risk of short sleep. The findings were consistent for specific berry types including strawberries and blueberries (p < 0.05). No significant associations with long sleep were found for total berries and any berry types. A decreased risk of sleep difficulties was found to be linked to blackberry consumption (adjusted OR = 0.63, 95% CI: 0.40-0.97; p = 0.036) but not for other berries.

CONCLUSIONS

US adult berry consumers had a decreased risk of reporting short sleep compared to nonconsumers. Berries are underconsumed foods in the US adult population, and increased berry consumption may improve sleep quality.

Sleep Deficiency and Cardiometabolic Disease

Epidemiologic studies have demonstrated that short sleep duration is associated with an increased risk of cardio-metabolic health outcomes including cardiovascular disease mortality, coronary heart disease, type 2 diabetes mellitus, hypertension, and metabolic syndrome. Experimental sleep restriction studies have sought to explain these findings. This review describes the main evidence of these associations and possible mechanisms explaining them. Whether sleep extension reverses these now widely acknowledged adverse health effects and the feasibility of implementing such strategies on a public health level is discussed.

Short sleep duration associated with the incidence of cardio-cerebral vascular disease: a prospective cohort study in Shanghai, China

IMPORTANCE

Sleep duration plays an important role in predicting CCVD incidence, and have implications for reducing the burden of CCVD. However, the association between sleep duration and predicted cardio-cerebral vascular diseases (CCVD) risk remains to be fully understood.

OBJECTIVE

To investigate the effects of sleep duration on the development of CCVD among Chinese community residents.

DESIGN

A prospective cohort study. The baseline survey was conducted from January 2013 to July 2013. The cohort has been followed until December 31, 2016 using a combination of in-person interviews and record linkages with the vital registry of Pudong New Area, Shanghai, China.

SUBJECTS

A total of 8245 Chinese community residents were initially enrolled in the cohort. Of those, 6298 underwent the follow-up examination.

EXPOSURE

Self-reported sleep duration and sleep quality were obtained via the questionnaire. Sleep duration was divided into five categories: ≤5, 6, 7, 8, or ≥ 9 h per day.

MAIN OUTCOME(S) AND MEASURE(S)

CCVD, Coronary heart disease (CHD) and Stroke occurrence, Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated using Fine-Gray proportional subdistribution hazards models.

RESULTS

During a median follow-up of 3.00 years (IQR 2.92-3.08), we observed 370 participants have had incident CCVD events, of whom 230 had CHDs, 169 had strokes, and 29 had both. After adjustment for relevant confounders, short sleepers (≤ 5 h) had 83% higher risk of total CCVD incidence (HR: 1.83; 95% CI: 1.32-2.54), 82% higher risk of CHD incidence (HR: 1.82; 95% CI: 1.21-2.75), and 82% higher risk of stroke incidence (HR: 1.82; 95% CI: 1.12-2.98) in contrast to the reference group (7 h). Some of these U-shaped relationships varied by age, and were more pronounced in individuals aged < 65 years. Individuals who slept ≤ 5 h per day with baseline hypertension had the highest risk of CCVD incidence (HR: 3.38, 95% CI 2.08-5.48), CHD incidence (HR: 3.11, 95% CI 1.75-5.53), and stroke incidence (HR: 4.33, 95% CI 1.90-9.86), compared with those sleep 7 h and without baseline hypertension.

CONCLUSIONS

Short sleep duration is independently associated with greater incidence of CCVD, CHD and stroke.

Acute effects of fresh versus dried Hayward green kiwifruit on sleep quality, mood, and sleep-related urinary metabolites in healthy young men with good and poor sleep quality

Background and aims

Daily kiwifruit (KF) consumption has been associated with improved sleep quality, but underlying physiological mechanisms are unknown. This study examined acute effects of fresh and dried green KF, compared with a water control, on sleep quality, mood, and urinary serotonin and melatonin metabolite concentrations.

Methods

24 men (age: 29 ± 1 years, body mass index: 24 ± 1 kg/m2) with poor (n = 12) or good (n = 12) sleep quality participated in a randomized, single-blind crossover study. One of three treatments was consumed with a standardized evening meal; (1) the flesh of two fresh green KF, (2) dried green KF powder (including skin; equivalent to dry matter of two fresh KF) mixed with water, or (3) a water control, in their own home. Subjective and objective sleep quality, mood, waking urinary 5-hydroxyindoleacetic acid (5-HIAA), 6-sulfatoxymelatonin (aMT6s), vitamin C and B-vitamin concentrations were determined.

Results

Regardless of sleep quality group, compared to control, morning sleepiness, alertness upon awakening, and vigor were improved (p &lt; 0.05) after dried KF consumption. Compared to control, both fresh and dried KF treatments tended (p &lt; 0.1) toward improved esteem and total mood disturbance. Both KF treatments increased (fresh +1.56 ± 0.4 ng/g, p = 0.001; dried: +1.30 ± 0.4 ng/g, p = 0.004) urinary concentration of the serotonin metabolite 5-HIAA compared to the control (4.32 ± 0.4 ng/g). In poor sleepers, ease of awakening improved by 24% after dried KF consumption (p = 0.005) and tended to improve by 13% after fresh KF intake (p = 0.052) compared to the control. Good sleepers tended toward 9% improved ratings of getting to sleep with fresh KF (p = 0.053) compared to the control. Poor sleepers had lower amounts of some B-vitamins compared to good sleepers (p &lt; 0.05).

Conclusion

Consumption of dried or fresh KF with a standard evening meal, was associated with improved aspects of sleep quality and mood, possibly mediated through changes in serotonin metabolism.

Clinical trial registration

[www.anzctr.org.au], identifier [ACTRN12621000046808].

Graphical Abstract

Changes in daily sleep duration and subsequent risk of mortality among older people

BACKGROUND

Single self-reported measures of daily sleep duration are associated with adverse health outcomes; however, the association between changes in daily sleep duration and all-cause mortality has not been thoroughly evaluated among a large group of older people.

METHODS

Using data from the Chinese Longitudinal Healthy Longevity Surveys, a total of 8588 older participants were included in the present study. Changes in daily sleep duration were assessed using annual changes, and Cox regression analysis examined the association of the annual changes with mortality.

RESULTS

The median age of the study population was 82.00 (IQR: 72.00, 90.00) years, and 3974 (46.27%) participants were men. During a median follow-up period of 3.81 (IQR: 2.03, 6.74) years, 5100 (59.39%) deaths were recorded. After adjusting for initial daily sleep duration and other confounders, there was a non-linear relationship between annual changes in daily sleep duration and all-cause mortality. Annual changes were not associated with mortality before 0.0 h/year, and mortality risk increased after 0.0 h/year, specially after 1 h/year (adjusted HR: 1.32 per 1-hour/year increment, 95% CI: 1.18-1.47). Compared to the stable group (annual changes between -1 and 1 h), adjusted HRs for mortality were 0.98 (95% CI: 0.89-1.08) for the shorter group (annual decline more than 1 h) and 1.29 (95% CI: 1.19-1.41) for the longer group (annual increase greater than 1 h), respectively. Stratified and sensitivity analyses suggested robustness of the results.

CONCLUSIONS

The present study suggested there was a non-linear relationship between annual changes in daily sleep duration and all-cause mortality among older people: longer changes were associated with higher mortality; while, shorter changes were not associated with mortality. Specially, mortality risk increased significantly with longer than 1 h of annual changes. The findings highlight the importance of closely monitoring the changes in daily sleep duration among older people.

Lifestyle Behaviors According to the Duration of Hypertension: Korea National Health and Nutrition Examination Survey 2016-2018

BACKGROUND

The aim of this study was to examine the lifestyle characteristics of hypertensive patients and to investigate the association between the duration of hypertension and lifestyle characteristics.

METHODS

A total 16,508 adults (including 5,933 hypertensive patients) aged 20 years and older who participated in the 7th Korea National Health and Nutrition Examination Survey 2016-2018 were analyzed. Multiple logistic regression analysis was performed to examine the association between the duration of hypertension and lifestyle factors.

RESULTS

The longer duration of hypertension was associated with lower risk of drinking in men (odds ratio [OR], 0.78; 95% confidence interval [CI], 0.66-0.93), and this observation remained when participants with hypertension for ≥ 13 years were compared to those with hypertension for < 1 year (OR, 0.57; 95% CI, 0.37-0.88). On the other hand, increased duration of hypertension increased the odds of engaging in high physical activity (PA) in women (OR, 1.72; 95% CI, 1.15-2.56), particularly in men with hypertension for 6-12 years (OR, 1.66; 95% CI, 1.03-2.69) and women with hypertension for ≥ 13 years (OR, 3.64; 95% CI, 1.38-9.62).

CONCLUSION

In conclusion, adoption and maintenance of healthy lifestyle habits, particularly drinking cessation in men, and PA in both men and women was observed, and differences were observed depending on the duration of hypertension.

Association between Sleep Duration and Symptoms of Depression Aged between 18 and 49: The Korea National Health and Nutrition Examination Survey (KNHANES Ⅶ) from 2016 to 2018

This study aimed to determine the association between symptoms of depression and sleep duration in a representative sample of the Korean population. Using national cross-sectional data from the seventh Korea National Health and Nutrition Examination Surveys (KNHANES-VII), 5461 adults aged 18−49 years were analyzed using logistic regression models. The proportions of participants with total daily sleep durations (24 h) of <6 h, 6−8 h, and ≥9 h were 26.2%, 60.6%, and 13.3%, respectively. The proportions of individuals with symptoms of depression in the <6 h, 6−8 h, and ≥9 h sleep duration groups were 37.4%, 46.3%, and 16.3%, respectively. The odds ratios (ORs) were significantly higher in the <6 h and ≥9 h sleep groups than in the 6−8 h sleep group. There was a significant association between short (<6 h/day) and long (≥9 h/day) sleep duration and symptoms of depression among the general Korean population. In particular, our findings suggest that short sleep (<6 h/day) is more associated with symptoms of depression than long sleep (≥9 h/day).

The association between bedtime at night and hypertension in adults

OBJECTIVE

This research was conducted to explore the association between bedtime at night and the prevalence of hypertension in adults.

METHODS

We conducted a cross-sectional study of 14,536 participants with data from the NHANES database. Bedtime was determined from the question in the sleep questionnaire: 'What time do you usually fall asleep on weekdays or workdays?.' Hypertension was defined as systolic blood pressure (SBP) ≥ 140 mmHg, or diastolic blood pressure (DBP) ≥ 90 mmHg, or having been told by a doctor to have high blood pressure, or taking antihypertensive medication. We conducted a weighted multiple logistic regression analysis to explore the relationship between bedtime at night and the prevalence of hypertension in adults.

RESULTS

The association between bedtime and hypertension showed a significantly U-shaped relationship. People who went to bed at 23:00 had the lowest risk of developing hypertension (OR, 0.68 [95%CI, 0.58, 0.81]). This U-shaped association still existed in different genders. In males (n = 7159), the adjusted OR was still lowest at 23:00. However, the adjusted OR was lowest at 0:00 in females(n = 7377). The interaction effect between bedtime and gender was significant (P = 0.0187).

CONCLUSION

With the delay in bedtime, the association between bedtime and hypertension showed a significantly U-shaped relationship. Falling asleep at 23:00 has the lowest risk of developing hypertension.

Effect of antihypertensive medications on sleep status in hypertensive patients

Purpose

Antihypertensive medication is an effective way to control blood pressure. However, some studies reported that it may affect patients' sleep quality during the treatment. Due to the inconsistency of present results, a comprehensive systematic review and network meta-analysis are needed.

Methods

Electronic databases (MEDLINE, EMBASE, WEB OF SCIENCE, PUBMED) were searched up to April 10th, 2021 including no restriction of publication status. Randomized controlled trials (RCTs) or quasi-experimental studies or cohort studies were eligible. The network meta-analysis was used within a Bayesian framework.

Results

Finally, 16 publications (including 12 RCTs and 4 quasi-experimental studies) with 404 subjects were included in this study. Compared to placebo, the results of the network meta-analysis showed that diuretics were effective in improving sleep apnea with a mean difference (MD) of - 15.47 (95% confidence interval [CI]: - 23.56, - 6.59) which was consistent with the direct comparison result (MD: - 17.91; 95% CI - 21.60, - 14.23). In addition, diuretics were effective in increasing nocturnal oxygen saturation with an MD of 3.64 (95% CI 0.07, 7.46). However, the effects of β-blockers, calcium channel blockers, angiotensin-converting enzyme inhibitors, angiotensin-receptor blockers, and the others on sleep apnea were not statistically significant. Additionally, the effects of antihypertensive medication on the total sleep time (min), rapid eye movement (%), and sleep efficiency (%) were not statistically significant.

Conclusion

Our study found that diuretics could effectively reduce the severity of sleep apnea in hypertensive patients. However, the effects of antihypertensive drugs on sleep characteristics were not found.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-022-00391-8.

Effects of sleep deprivation on coronary heart disease

The presence of artificial light enables humans to be active 24 h a day. Many people across the globe live in a social culture that encourages staying up late to meet the demands of various activities, such as work and school. Sleep deprivation (SD) is a severe health problem in modern society. Meanwhile, as with cardiometabolic disease, there was an obvious tendency that coronary heart disease (CHD) to become a global epidemic chronic disease. Specifically, SD can significantly increase the morbidity and mortality of CHD. However, the underlying mechanisms responsible for the effects of SD on CHD are multilayered and complex. Inflammatory response, lipid metabolism, oxidative stress, and endothelial function all contribute to cardiovascular lesions. In this review, the effects of SD on CHD development are summarized, and SD-related pathogenesis of coronary artery lesions is discussed. In general, early assessment of SD played a vital role in preventing the harmful consequences of CHD.

Association between sleep duration and hypertension in southwest China: a population-based cross-sectional study

OBJECTIVE

Hypertension is a major risk factor and cause of many non-communicable diseases in China. While there have been studies on various diet and lifestyle risk factors, we do not know whether sleep duration has an association to blood pressure in southwest China. This predictor is useful in low-resource rural settings. We examined the association between sleep duration and hypertension in southwest China.

DESIGN

Population-based cross-sectional study.

SETTING

This study was part of the baseline survey of a large ongoing prospective cohort study, the China Kadoorie Biobank. Participants were enrolled in 15 townships of Pengzhou city in Sichuan province during 2004-2008.

PARTICIPANTS

55 687 participants aged 30-79 years were included. Sleep duration was assessed by a self-reported questionnaire.

MAIN OUTCOME MEASURES

Hypertension was defined as systolic blood pressure ≥140 mm Hg and/or diastolic blood pressure ≥90 mm Hg, or prior physician-diagnosed hypertension in hospitals at the township (community) level or above.

RESULTS

The prevalence of hypertension was 25.17%. The percentages of subjects with sleep durations of <6, 6, 7, 8 and ≥9 hours were 17.20%, 16.14%, 20.04%, 31.95% and 14.67%, respectively. In multivariable-adjusted analyses, the increased ORs of having hypertension were across those who reported ≥9 hours of sleep (men: 1.16, 95% CI 1.04 to 1.30; women: 1.19, 95% CI 1.08 to 1.32; general population: 1.17, 95% CI 1.08 to 1.26). The odds of hypertension was relatively flat until around 6.81 hours of sleep duration and then started to increase rapidly afterwards in subjects and a J-shaped pattern was observed. There was a U-shaped relationship between sleep duration and hypertension in females.

CONCLUSION

Long sleep duration was significantly associated with hypertension and a J-shaped pattern was observed among rural adults in southwest China, independent of potential confounders. However, this association was not obvious between short sleep duration and hypertension.

Sleep Deficiency and Cardiometabolic Disease

Epidemiologic studies have demonstrated that short sleep duration is associated with an increased risk of cardio-metabolic health outcomes including cardiovascular disease mortality, coronary heart disease, type 2 diabetes mellitus, hypertension, and metabolic syndrome. Experimental sleep restriction studies have sought to explain these findings. This review describes the main evidence of these associations and possible mechanisms explaining them. Whether sleep extension reverses these now widely acknowledged adverse health effects and the feasibility of implementing such strategies on a public health level is discussed.

Association between sleep duration on workdays and blood pressure in non-overweight/obese population in NHANES: a public database research

This study aimed to explore the association between sleep duration on workdays and blood pressure (BP) including systolic blood pressure (SBP) and diastolic blood pressure (DBP) in non-overweight/obese population. A cross-sectional study composed of 2887 individuals from NHANES was conducted. Subjective sleep duration on workdays were evaluated by the questionnaire. Multiple linear regression analyses were done to explore the relationship between sleep duration and BP. Compared with sleep duration of 6-8 h, both sleep duration < 6 h and ≥ 8 h on workdays were significantly associated with increased SBP (β, 3.58 [95% CI 1.60, 5.56] and 1.70 [95% CI 0.76, 2.64], respectively). However, the significant association was not founded in DBP. The stratified analyses showed that in females, sleep duration (< 6 h or ≥ 8 h) on workdays were associated with SBP (β = 5.99 and 2.41, respectively, both P < 0.0005). In addition, the SBP levels were much higher among participants aged (≥ 60) with sleep duration < 6 h. The effect size was 7.23 (P = 0.0217). In the subgroup classified by race, a significantly positive association between sleep duration (< 6 h, ≥ 8 h) and SBP can be seen in the White population (β = 6.64 (P = 0.0007) and 1.91 (P = 0.0215), respectively). In non-overweight/obese population, both short sleep duration (< 6 h) and long sleep duration (≥ 8 h) on workdays were correlated with higher level of SBP.

Association Between Bedtime at Night and Systolic Blood Pressure in Adults in NHANES

Objectives: This study aimed to explore the association between bedtime at night and systolic blood pressure (SBP) in adults.

Methods: We conducted a cross-sectional study composed of 7,642 individuals from the National Health and Nutrition Examination Survey (NHANES). Bedtime was defined as the response to the question: “What time do you usually fall asleep on weekdays or workdays?” SBP was taken using the average of all measured values. Multiple linear regression analyses were done to explore the relationship between bedtime and SBP.

Results: The bedtime was changed from categorical variable to continuous variable for data analysis, and a significantly negative association was identified between bedtime and SBP (β, −0.23 [95% CI, −0.43, −0.02]). With the delay of bedtime, the SBP showed a gradual decrease trend, and it was dropped to the lowest at 0:00. After 0:00, the SBP was gradually increased with the delay of sleep time. The stratified analyses showed that in the female group, with the delay of bedtime, the range of SBP was decreased more obviously at 0:00. In the 18–45 year group, bedtime had little effect on SBP. Among ≥45 years old group, this trend was still the same. In the black group, an obvious downward trend was found at 22:00.

Conclusion: With the delay of bedtime, the SBP had shown a gradual decrease trend, and it was dropped to the lowest at 0:00. After 0:00, the SBP was gradually increased with the delay of sleep time. Bedtime and SBP showed a U-shaped relationship.

Association Between Sleep Quality and Hypertension in Chinese Adults: A Cross-Sectional Analysis in the Tianning Cohort

BACKGROUND

Poor sleep quality is becoming very common in a developed society and relates to many health disorders. However, the association between sleep quality and hypertension has not been well studied in Chinese adults.

METHODS

Blood pressure was measured and sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI) for 5167 participants (mean aged 51±15 years, 41.5% males) in the Tianning Cohort. A logistic regression model was constructed to examine the association between sleep quality, as well as its components, and hypertension, adjusting for age, sex, education level, current smoking, current drinking, physical activity, obesity, glucose, and blood lipids.

RESULTS

After multivariate adjustment, a higher score Of the PSQI was significantly associated with an increased risk of prevalent hypertension (OR=1.03, P=0.018). Compared to participants with normal sleep (the PSQI score <5), those with a poor sleep quality (the PSQI score ≥5) had a 17% increased risk of prevalent hypertension (OR=1.17, P=0.042). Three of the seven components of sleep quality, such as subjective sleep quality (OR=1.17, P=0.001), sleep latency (OR=1.11, P=0.010), and sleep disturbances (OR=1.19, P=0.004), were also significantly associated with prevalent hypertension.

CONCLUSION

Poor sleep quality is increasingly prevalent in developed societies and may be related to an increased risk of hypertension in Chinese adults. The underlying causality is waiting to be studied.

Healthy Sleep Associated With Lower Risk of Hypertension Regardless of Genetic Risk: A Population-Based Cohort Study

Background: Hypertension is a leading contributor to the global burden of disease and to mortality. The combined effects of sleep factors on the risk of hypertension are unclear. We aimed to evaluate the effect of combined sleep factors on the risk of hypertension and to explore whether this association is independent of genetic risk. Methods: This population-based prospective cohort study included 170,378 participants from the UK Biobank study. We conducted a healthy sleep score based on a combination of major five sleep factors and a genetic risk score based on 118 risk variants. Cox proportional hazard regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results: A total of 170,378 participants were included. Compared to participants with a healthy sleep score of 0-1, those with healthy sleep scores of 2 (HR, 0.90; 95% CI, 0.83-0.98), 3 (HR, 0.81; 95% CI, 0.75-0.88), 4 (HR, 0.74; 95% CI, 0.68-0.81), or 5 (HR, 0.67; 95% CI, 0.59-0.77) had increasingly lower risks of hypertension (P for trend <0.001). Participants with high genetic risk and an unfavorable sleep pattern had a 1.80-fold greater risk of hypertension than participants with low genetic risk and a favorable sleep pattern. The association between sleep patterns and hypertension persisted in subgroup analysis, stratified by the genetic risk. Nearly 18.2% of hypertension events in this cohort could be attributed to unfavorable sleep pattern. Conclusions: Favorable sleep pattern was associated with a low risk of hypertension, regardless of genetic risk. These findings highlight the potential of sleep interventions to reduce risk of hypertension across entire populations.

Poor sleep quality is associated with new-onset hypertension in a diverse young and middle-aged population

BACKGROUND

Sleep disorders have been proposed as the potential risk factors for hypertension, thus we aimed to investigate the association of sleep quality with new-onset hypertension.

METHODS

We evaluated sleep quality using Pittsburgh Sleep Quality Index (PSQI) and it's seven components in normotensive population aged 18 years old and over in Emin Xinjiang, China in 2016 and followed up till 2019 using annual health checkup data. Poor sleep quality was defined as a PSQI score>5, and good sleep quality was defined as a PSQI score⩽5.

RESULTS

Among 9344 analytic sample 57.29% were female. A total of 2958 (31.66%) subjects developed hypertension during 22,960 person-years of follow-up. Poor sleep quality (HR 1.131, 95% CI 1.045, 1.224) showed had higher risk of development hypertension in total population in adjusted Cox models. Fairly bad subjective sleep quality (HR 1.148, 95% CI 1.015, 1.298), habitual sleep efficiency of <65%-75% group (HR 1.174, 95% CI 1.026, 1.344), and mild (HR 1.194, 95% CI 1.098, 1.299) and moderate (HR 1.264, 95% CI 1.080, 1.479) sleep disturbance increased the risk of developing hypertension compared to their counterparts. In age stratification, poor sleep quality (HR 1.100, 95% CI 1.007, 1.202) had higher risk of developing hypertension in the young and middle-aged population after adjusted all covariates.

CONCLUSIONS

Poor sleep quality is associated with higher risk of new-onset hypertension in young and middle-aged population.

Digital health device measured sleep duration and ideal cardiovascular health: an observational study

BACKGROUND

Studies relying on self-reported sleep data suggest that there is an association between short and long sleep duration and less than ideal cardiovascular health. Evidence regarding the feasibility of using digital health devices to measure sleep duration and assess its relationship to ideal cardiovascular health are lacking. The objective of the present study was to utilize digital health devices to record sleep duration and examine the relationship between sleep duration and ideal cardiovascular health.

METHODS

A total of 307 participants transmitted sleep duration data from digital health devices and answered the Life's Simple 7 survey instrument to assess ideal cardiovascular health. Sleep duration was defined as adequate (7 to < 9 h per night) or non-adequate (< 7 h and ≥ 9 h).

RESULTS

We identified three sleep-cardiovascular health phenogroups: resilient (non-adequate sleep and ideal cardiovascular health), uncoupled (adequate sleep and non-ideal cardiovascular health) or concordant (sleep and cardiovascular health metrics were aligned). Participants in the resilient phenogroup (n = 83) had better cardiovascular health factor profiles (blood pressure, blood glucose and cholesterol levels) and behaviors (healthy weight, diet, exercise, smoking) than participants in the concordant (n = 171) and uncoupled (n = 53) phenogroups. This was associated with higher Life's Simple 7 Health Scores in the resilient phenogroup compared to the concordant and uncoupled phenogroups (7.8 ± 0.8 vs. 7.0 ± 1.4 vs. 5.6 ± 0.7, P < 0.01).

CONCLUSION

This study identified three distinct sleep-ideal cardiovascular health phenogroups and highlights the advantage of incorporating sleep assessments into studies of cardiovascular health. Future studies should focus on the relationship between sleep-cardiovascular phenogroups and clinical outcomes. Clinical Trial Registration Clinicaltrials.gov NCT02958098. Date of registration: November 11, 2016.

Loss of nocturnal dipping pattern of skin sympathetic nerve activity during and following an extended-duration work shift in residents in training

BACKGROUND

Extended-duration work shifts (EDWSs) might affect the health of physician residents, causing autonomic alteration. Skin sympathetic nerve activity (SKNA) recorded by noninvasive neuro-electrocardiography (neuECG) is used to estimate cardiac sympathetic tone. In this study, we aim to evaluate the impact of EDWSs on nocturnal SKNA assessed in resident doctors.

METHODS

Twenty-four residents working EDWSs and 12 PhD students not working nightshift schedules were prospectively recruited. The neuECG was performed between 12 am and 6 am for 5 consecutive nights. SKNA was filtered from neuECG recorded signals. The questionnaires regarding work stress and sleep quality, blood pressure, and salivary alpha-amylase and cortisol levels were administered.

RESULTS

The hours of weekly working and sleep opportunities were similar between residents and students, while residents reported more work stress and worse sleep quality. In residents, SKNA at 6 am (SKNA_6am) was significantly higher than SKNA_2am during the precall night, revealing a dipping pattern. However, the SKNA dipping disappeared during the on-call night and prominently flattened during the first postcall night, the full recovery of which was delayed until the second postcall nights. The morning blood pressure and salivary alpha-amylase and cortisol levels were similar between the precall and postcall days. In contrast, SKNA in students exhibited a constant dipping profile for all recorded nights.

CONCLUSIONS

In healthy young adults, SKNA presents a dip night. The SKNA dip is impaired by working a nightshift, with a delayed recovery. The neuECG might serve as a useful tool to detect subclinical autonomic disturbances in shiftworkers.

Hemodynamics Changes in the Phase Before, During, and After Sleep Based on Patients’ Sleep Quality in High Care Unit

BACKGROUND: Sleep is a human physiological need that must be fulfilled. Sleep disturbance is generally experienced by hospitalized patients and measured by sleep quality. Sleep disturbance can adversely affect hemodynamic parameters, physiological, and psychological outcome that contribute to the healing of patients. However, few literatures discussing the hemodynamic changes based on the patients’ sleep quality. AIM: The study aimed to describe the hemodynamic changes before, during, and after sleeping phases METHODS: This is an observational analytic quantitative study conducted between February and March 2019 and involved 45 patients. The samples were the conscious patients, aged between 18 and 60 years old (adult) and had been hospitalized for more than 2 days. The Richards-Campbell Sleep Questionnaire was utilized to measure the patients sleep quality, while hemodynamic values were observed by patients’ bedside monitor before, during and after sleep. Data analysis used the Friedman test to determine hemodynamic changes. RESULTS: The results showed that most respondents were female (75.6%), used oxygen (46.7%), sleep in supine position (55.6%), and average age of 35.47 (standard deviation [SD] = 9.581) years old. Patients’ sleep quality score was 44.27 (SD = 22.809), with the average days of treatment were 2.47 days (SD = 694). The average score of Hemodynamic Mean Arterial Pressure (MAP), Heart Rate (HR), and Oxygen saturation (SpO2) before sleeping was 97.64, 94.04, and 94.09, during sleeping was 89.87, 85.00, and 91.22 while after sleeping was 98.27, 97.56, and 97.89, respectively. There was a significant change in HR with p = 0.019, and there was no significant change in the MAP (p = 0.152) and SpO2 (p = 0.149) CONCLUSION: There were variations in hemodynamic score changes before, during, and after sleep, changes in MAP, HR, and SpO2 score within normal ranges. The high hemodynamic changes in the early phase, decrease during sleep, and rise again after sleep. HR is a hemodynamic parameter that significantly changes in those three phases. Monitoring of hemodynamic values in patients could be carried out in the before, during, and after sleep phases to determine the patients’ physiological and psychological condition so as to contribute the healing process.

The association of nighttime sleep duration and daytime napping duration with hypertension in Chinese rural areas: a population-based study

We aimed to investigate the association of self-reported nighttime sleep duration and daytime napping duration with hypertension in rural areas of China. The participants, who were from rural areas of Hunan Province in China, were enrolled during 2016-2017. Nighttime sleep duration (<7 h, 7-8 h, and ≥9 h) and daytime napping duration(no nap, 0-1 h, and >1 h) were determined by a self-reported questionnaire. Hypertension was defined as a mean systolic blood pressure ≥140 mmHg and/or a mean diastolic blood pressure ≥90 mmHg or a self-reported physician diagnosis of hypertension and current use of antihypertensive medication. Of 1763 enrolled participants, 52% had hypertension. A total of 640 (36%) were male and 1123 (64%) were female; the mean age was 56 years. After adjusting for potential confounders, participants who slept for ≥9 h per night had a 1.29-fold (95% CI: 1.03, 1.60) increased odds of hypertension compared to the reference group (7-8 h per night). Daytime napping >1 h was negatively associated with hypertension, with an adjusted OR (95% CI) of 0.70 (0.51, 0.97), and the protective effect of longer daytime napping was still found in the subgroup sleeping 7-8 h per night. Among the rural population in China, long nighttime sleep duration is associated with a higher prevalence of hypertension, and longer daytime napping is related to a decreased prevalence of hypertension.

Sleep Duration and Cardiovascular Health in a Representative Community Population (from NHANES, 2005 to 2016)

The 2016 American Heart Association Scientific Statement on sleep duration and cardiovascular risk suggested that optimal sleep duration is critical for cardiovascular health, with both long and short sleep duration associated with adverse health outcomes. We examined the relation between sleep duration and cardiovascular health among the general population in the United States from 2005 to 2016. We sought to investigate associations between sleep duration and the prevalence of coronary artery disease, heart failure (HF), stroke, hypertension, diabetes mellitus (DM), and hyperlipidemia. Using the National Health and Nutrition Examination Survey, we identified all patients with HF, coronary artery disease, hypertension, hyperlipidemia, DM, and stroke from 2005 to 2016. Multivariable logistic regression analyses were performed to adjust for age, sex, body mass index (BMI), marital status, educational level, physical activity, sedentary activity, depression, blood pressure, lipid profiles, and hemoglobin. In total, 32,152 National Health and Nutrition Examination Survey participants responded to the sleep survey. Both short sleepers (<7 hours, n = 12,027) and long sleepers (>9 hours, n = 1,058) were older and more likely to have a higher BMI than optimal sleepers (7 to 9 hours, n = 19,067; all p values <0.05). After adjusting for confounding variables and in comparison to those with optimal sleep duration, short sleep duration was associated with a higher prevalence of previous stroke (odds ratio [OR] 1.45; 95% confidence intervals [CI] 1.23 to 1.70), HF (OR 1.65; 95% CI 1.40 to 1.95), DM (OR 1.35; 95% CI 1.23 to 1.49), and hyperlipidemia (OR 1.12; 95% CI 1.04 to 1.22), whereas long sleep duration was associated with a higher prevalence of previous stroke (OR 1.81; 95% CI 1.37 to 2.34) and HF (OR 1.47; 95% CI 1.08 to 1.97). In conclusion, both long and short sleep durations were associated with poor cardiovascular health in this cross-sectional study.

Auricular Acupressure in Patients with Hypertension and Insomnia: A Systematic Review and Meta-Analysis

Objective

The efficacy of auricular acupressure in patients with hypertension and insomnia is controversial. This systematic review aims to explore the effectiveness of auricular acupressure in reducing blood pressure and improving sleep in this population.

Methods

We conducted an extensive database search in Cochrane Central Register of Controlled Trials, PubMed, Ovid LWW, Web of Science, Chinese Biomedical Literature Database, China Knowledge Resource Integrated Database, Wanfang Data, and China Science and Technology Journal Database on randomized controlled trials published from inception to November 2019 that compared auricular acupressure with a control or comparison group on blood pressure control and sleep improvement. Two reviewers independently conducted data screening and extraction. Study quality was evaluated using the Cochrane Handbook for Systematic Reviews of Interventions. Meta-analyses were performed on blood pressure, Pittsburgh Sleep Quality Index (PSQI), the efficacy rate of diagnostic and therapeutic criteria for traditional Chinese medicine syndromes (DTCTCMS), and the efficacy rate of guidelines for traditional Chinese medicine (new drug) clinical research (GTCMCR) by Revman 5.3.0.

Results

A total of 18 randomized controlled trials with 1685 patients were identified. Compared with a control or comparison group, pooled meta-analyses showed that auricular acupressure significantly improved systolic blood pressure (MD = −15.05, 95% CI (−18.49, −11.61), P < 0.00001), diastolic blood pressure (MD = −8.41, 95% CI (−11.33, −5.48), P < 0.00001), PSQI (MD = −2.37, 95% CI (−4.64, −0.10), P=0.04), the efficacy rate of DTCTCMS (RR = 1.63, 95% CI (1.16, 2.28), P=0.004), and the efficacy rate of GTCMCR (RR = 1.25, 95% CI (1.12, 1.38)).

Conclusions

The results demonstrated a favorable effect of auricular acupressure to reduce blood pressure and improve sleep in patients with hypertension and insomnia. Further studies to better understand the acupoints and intervention times of auricular acupressure are warranted.

Association between sleep duration and osteoarthritis and their prevalence in Koreans: A cross-sectional study

OBJECTIVE

To determine the association of radiological and symptomatic osteoarthritis with sleep duration in a representative sample of the Korean population.

METHODS

Using data from the national cross-sectional fifth Korea National Health and Nutrition Examination Survey 2010-2012. Of the 16,528 participants in KNHANES-V, 8,918 were adults aged≥ 50 years who had completed the survey questions on sleep duration and osteoarthritis, and had diagnostic X-ray results. We evaluated the association between sleep duration as the primary predictor for osteoarthritis involving the hip, knee, and spinal joints. A complex sample logistic regression analysis was performed to adjust for the covariates.

RESULTS

Proportions of participants with total daily sleep duration of ≤6 hours, 7-8 hours, and ≥9 hours were 47.1%, 45.2, and 7.7%, respectively. The rate of osteoarthritis diagnoses in the ≤6 hours, 7-8 hours, and ≥9 hours of sleep duration groups was 24.1%, 17.6%, and 21.8%, respectively (p <0.0001). The odds ratios (OR) were significantly higher in the ≤6 hours of sleep group than in the 7-8 hours of sleep group (OR, 1.20; 95% confidence interval [CI], 1.03-1.39; p = 0.02), but no significant difference in the ≥9 hours of sleep group was found after adjusting the confounding variables. When we compared knee joint pain (Numeric Rating Scale 0 versus 1-10) in participants with grade 2-4 Kellgren-Lawrence (KL) classification after adjusting these same confounding variables, the ≤6 hours of sleep group (OR, 1.32; 95% CI, 1.10-1.58) and the ≥9 hours of sleep group (OR, 1.41; 95% CI, 1.03-1.95) showed significantly higher ORs.

CONCLUSION

This study confirmed the significant association between sleep duration and osteoarthritis in adults aged ≥50 years. Participants' positive for both radiological (KL grade ≥2) and symptomatic osteoarthritis showed a strong association between knee joint pain and not enough sleep duration.

Sleep quality, sleep duration, and their association with hypertension prevalence among low-income oldest-old in a rural area of China: A population-based study

OBJECTIVE

The relationship among sleep quality, sleep duration and hypertension prevalence is controversial in different age groups and genders. This study aimed to investigate sleep quality, sleep duration and their association with hypertension prevalence among low-income oldest-old in a rural area of China.

METHODS

A cross-sectional survey was conducted in a representative sample of 1066 adults aged 80-99 years in 2017. Logistic regression analysis was performed.

RESULTS

Among males, sleep durations of <6 h and 6-<7 h were significantly associated with hypertension prevalence, with odds ratios (ORs) of 3.15 (95% confidence interval (CI) 1.37 to 7.23) and 2.38 (95% CI 1.22 to 4.63), respectively. Among females, only the sleep duration of <6 h was associated with increased OR of hypertension of 3.49 (95% CI 1.50 to 8.09). Poor sleep quality was associated with hypertension for both genders (OR_men 1.67, 95% CI 1.12 to 2.49; OR_women 1.91, 95% CI 1.29 to 2.82). For women, a combination of poor sleep quality and any group of sleep duration, except for 7-<8 h, was associated with higher hypertension prevalence. For men, only the combination of poor sleep quality and short sleep duration (<7 h) was associated with high hypertension prevalence.

CONCLUSION

Short sleep duration and poor sleep quality are associated with hypertension prevalence of oldest-old. The prevention of hypertension in older adults should be investigated from the perspective of sleep improvement.

Association between sleep duration and hypertension of migrant workers in China: a national cross-sectional surveillance study

OBJECTIVES

To examine the relationship between sleep duration and hypertension of migrant workers aged 18-59 years in China.

DESIGN

Population-based cross-sectional study using a complex survey sampling design.

PARTICIPANTS

There were 43 655 subjects in our analysis, after excluding people with missing information for key exposure and outcome variables and abnormal values for sleep duration (≤2 or ≥17 hours).

PRIMARY OUTCOME MEASURE

Hypertension was defined as systolic blood pressure (BP) ≥140 mm Hg and/or diastolic BP ≥90 mm Hg, or self-reported history of hypertension diagnosis in hospitals at the township (community) level or above and use of hypertensive medicine in the last 2 weeks.

RESULTS

Of 43 655 subjects, 15.6% (95% CI 15.1% to 16.1%) of migrant workers had hypertension. The prevalence of hypertension decreased with the increased sleep duration, both in males and females. Logistic regression models, using 7-8 hours sleep/day as the reference, showed a greater odds for hypertension among men and women who reported <6 hours of sleep after adjusting for sociodemographic characteristics, behavioural risk factors, body mass index, diabetes, stroke and myocardial infarction (men: OR 1.26; 95% CI 1.03 to 1.54, women: OR 1.55; 95% CI 1.13 to 2.06, p_interaction=0.096). Further stratified by age and migration time, it revealed that among adults less than 45 years old, those sleeping 9 or more hours had adjusted odds for hypertension of 0.82 (95% CI 0.72 to 0.93, p_interaction=0.020),while there was no evidence of an association between sleep duration and hypertension among adults aged 45-59 years. Among adults whose migration time was less than 4.5 years, those sleeping 9 or more hours had adjusted odds for hypertension of 0.80 (95% CI 0.68 to 0.94, p_interaction=0.097).

CONCLUSION

The association between sleep duration and hypertension varies by age. Short sleep duration (<6 hours) is associated with an increased prevalence of hypertension in both genders.

Association of long-term sleep habits and hypertension: a cross-sectional study in Chinese adults

Poor sleep has been associated with risk of hypertension, but previous studies were limited by treating one or two sleep factors as predictor. Our previous study has developed a sleep factor questionnaire (SFQ) to comprehensively assess wide range of sleep characteristics including sleep duration, sleep quality, light at night (LAN) exposure, night/shift work, daytime napping, and frequency of nighttime waking, insomnia, and snoring. In this cross-sectional study we used the SFQ to evaluated the associations between these sleep domains and hypertension. Comparing with the subjects who slept 7-8 h, subjects with sleep duration 6-7 h (OR = 1.42, 95% CI: 1.01, 2.00), 8-9 h (OR = 1.60, 95% CI: 1.07, 2.40), and over 9 h (OR = 2.39, 95% CI: 1.60, 3.58) had an increased prevalence of hypertension. The associations were significant among individuals under 45 years sleeping 6-7 h and those over 45 years sleeping over 8 h. The OR of prevalent hypertension was 0.80 (95% CI: 0.62, 0.97) for habitual daytime napping compared with never napping, and the association was also significant among individuals over 45 years old. Moreover, among subjects with sleep duration 7-8 h, habitual daytime napping may decrease prevalent hypertension (OR = 0.635, 95% CI: 0.437, 0.924). In conclusion, our data suggested a positive association between both short (6-7 h) and long sleep duration and hypertension, and a preventive pattern for habitual daytime napping among over 45 years old and hypertension. Moreover, interaction analysis indicated that habitual midday nap may decrease prevalent hypertension among subjects with sleep duration 7-8 h.

Examining social capital in relation to sleep duration, insomnia, and daytime sleepiness

OBJECTIVE

Sleep, which plays an important role in health and well-being, is socially patterned such that certain demographic groups have worse sleep health than others. One possible mechanism driving sleep disparities is social capital. The current study examines the association between social capital and self-reported sleep variables (eg, duration, insomnia symptoms, and daytime sleepiness) among a sample of 1007 participants from the Sleep Health and Activity, Diet and Environment Study (SHADES).

METHODS

Logistic regressions were used to estimate whether the sleep variables were associated with social capital measures. All models control for age, sex, race/ethnicity (Non-Hispanic White, Black/African-American, Hispanic/Latino, Asian, and multicultural/other), income, and education (less than high school, high school graduate, some college, and college graduate).

RESULTS

Lower likelihood of membership in groups was seen for long sleepers (>9hrs, p-value<0.05) and beliefs that neighbors rarely/never help each other was more likely among short sleepers (5-6hrs, p-value<0.05), relative to 7-8 h sleepers. A decreased sense of belonging was seen among short sleepers (5-6hrs, p-value<0.05). Decreased likelihood of trust was reported by those with moderate-severe insomnia (p-value<0.05). Similarly, neighborhood improvement efforts were less likely among individuals with moderate-to-severe insomnia (p-value<0.05).

CONCLUSIONS

Results of our study show that short and long sleep duration, as well as insomnia, were inversely related to measures of social capital, such as group memberships and a sense of neighborhood belonging. Future research may explore the directionality of the relationship between social capital and sleep and perhaps consider future interventions to improve low social capital and/or poor sleep in community samples.

Sleep Duration and Blood Pressure: Recent Advances and Future Directions

PURPOSE OF REVIEW

This review discusses the recent literature on subjectively and objectively assessed sleep duration in relation to hypertension risk and out-of-clinic blood pressure (BP) measures and highlights critical areas for future research.

RECENT FINDINGS

Sleep duration, particularly short sleep, may influence BP through disturbed autonomic balance, hormonal imbalances, increased adiposity and metabolic dysfunction, and disrupted circadian rhythms. Observational studies indicate that short and long sleep are associated with hypertension risk, reduced nocturnal dipping, and elevated morning BP, but evidence is stronger for short sleep. Experimental sleep restriction increases BP, while sleep extension may lower BP in prehypertensive individuals. Women and racial/ethnic minorities are more prone to the detrimental effects of short sleep on BP. Additional studies are warranted to clarify the association of objectively assessed sleep with BP level and diurnal pattern and to determine the sex- and race-specific effects of sleep restriction and extension on BP.

Reciprocal Roles of Sleep and Diet in Cardiovascular Health: a Review of Recent Evidence and a Potential Mechanism

PURPOSE OF REVIEW

This review investigates the potential bi-directional relation between sleep and diet in considering their contribution to cardiovascular health. We further explore the involvement of the gut microbiome in the relationships between poor sleep and dietary intakes and increased cardiovascular disease (CVD) risk.

RECENT FINDINGS

There is strong evidence that sleep restriction leads to unhealthy food choices and increased energy intake. The diet may impact sleep, as well. Epidemiological studies show that higher adherence to a Mediterranean dietary pattern predicts healthier sleep. One factor that could underlie these relationships is the gut microbiome. Although data are mixed, there is some evidence that sleep restriction can influence the composition of the gut microbiome in humans. Similarly, Mediterranean diets and other plant-rich diets are related to increased diversity of the microbiota. At present, few studies have investigated the influence of the microbiome on sleep; however, limited evidence from epidemiological and intervention studies suggest that the composition of the microbiome may relate to sleep quality. More research is needed to better understand the role of the microbiome in the multi-directional relationship between sleep, diet, and CVD. There is growing evidence of a bi-directional relationship between sleep and the diet, which could act in concert to influence CVD risk. Diets such as the Mediterranean diet, comprised of high intakes of fruits, vegetables, and other plant-based foods, may promote healthy sleep and beneficial gut microflora. The gut microbiome may then underlie the relation between diet, sleep, and CVD risk.

The impact of sleepwear fiber type on sleep quality under warm ambient conditions

BACKGROUND

Sleep disturbance in adults with no health concerns is often linked to the thermal environment. This study assesses the impact on sleep quality of sleepwear made from fibers with different thermal insulation and hygral properties. This randomized cross-over study investigated the effects on sleep quality of sleepwear made from cotton, polyester and Merino wool in adults aged 50-70 years, at an ambient temperature of 30 °C and a relative humidity of 50%.

METHODS

Thirty-six healthy participants completed four nights of sleep study with polysomnography. Participants were categorized by body mass index as <25 kg·m^-2 or ≥25 kg·m^-2, age as <65 years or ≥65 years, and by Pittsburgh Sleep Quality Index (PSQI) as poor sleepers (PSQI≥5) or good sleepers (PSQI<5).

RESULTS

Small, but statistically significant sleep benefits were observed for wool over cotton and polyester sleepwear for multiple sleep parameters, while neither cotton nor polyester was responsible for any statistically significant sleep benefit over the 11 sleep parameters examined. The key findings were: 1) A significant sleepwear effect was observed for sleep onset latency (SOL), p=0.04. 2) For older participants, sleeping in wool significantly reduced SOL (12.4 mins) compared with cotton (26.7 mins, p=0.001) or polyester (21.6 mins, p=0.001). 3) A statistically significant effect was found for sleep fragmentation index (p=0.01) in which wool sleepwear (12.1 no·h^{- 1}) was lower than polyester (13.7 no·h^{- 1}) (p=0.005), but not different to cotton (13.3 no·h^{- 1}). 4) Poor sleepers had less wakefulness when sleeping in wool compared to cotton (p=0.047). 5) And Poor sleepers had higher rapid eye movement sleep latency in polyester than in cotton (p=0.037) or in wool (p=0.036).

CONCLUSION

Statistically significant benefits for wool sleepwear were observed on average for all participants and, in particular, for the older and poorer sleepers. There were no significant differences in any sleep variables between sleepwear types for the BMI sub-group.

A dose-response association of night sleep duration with hypertension in a Chinese rural population: the Henan Rural Cohort Study

The purpose of the study was to determine if there was a relationship between night sleep duration and hypertension, and to evaluate as to whether blood lipid levels played a role in this relationship. A total of 37,317 participants aged 18-79 years were included in this study. Night sleep duration was classified as <5, 5-, 6-, 7-, 8-, 9-, and ≥10 hours. Logistic regression and restricted cubic spline analysis was carried out to evaluate the association of sleep duration with hypertension. Compared with reference sleep duration (7 hours), in males, the multivariate odds ratios (ORs) (95% confidence interval [95% CI]) of the groups with longest sleep duration (≥10 hours) and shortest sleep duration (<5 hours) for hypertension was 1.52 (1.25-1.84) and 1.07 (0.80-1.44), respectively. Similarly, the longest sleep duration was associated with diagnosed hypertension (1.21, 1.00-1.45) in females. The OR for an indirect effect of sleep duration through low-density lipoprotein cholesterol (LDL-C) on hypertension was 1.085 (95% CI 1.038-1.137). Overall, a 3.5% possibility of hypertension being associated with sleep duration was attributable to LDL-C. In summary, a relationship between sleep duration and hypertension was observed in this rural population. LDL-C appeared to partially mediate the effect of sleep duration on hypertension in males.

Relationship of sleep duration on workdays and non-workdays with blood pressure components in Chinese hypertensive patients

Objectives: This study aimed to assess the relationship of sleep duration on workdays and non-workdays with BP components [systolic BP (SBP), diastolic (DBP), pulse pressure (PP), and mean arterial pressure (MAP)] among Chinese hypertensive adults. Methods: The study included 3,376 hypertensive patients without antihypertensive treatment. Self-reported sleep durations on workdays and non-workdays were measured by the questionnaire. Multiple linear regression analyses were performed to evaluate the association of sleep duration with BP components. Results: Overall, compared with a sleep duration of 5-9 h, individuals who slept ≥10 h on both workdays and non-workdays were positively correlated with SBP [β (95% CIs) = 3.99 (1.06, 6.93) and 4.33 (1.79, 6.87)] and PP [β (95% CIs) = 3.25 (0.71, 5.79) and 3.05 (0.85, 5.25)], but not with DBP. Moreover, individuals who slept ≥10 h only on non-workdays had higher MAP [β (95% CIs) = 2.30 (0.63, 3.97)]. The stratified analyses showed that subjects with a BMI ≥24 kg/m² in the longer sleep duration group (≥10 h) only on workdays compared to the reference group had higher SBP, DBP and MAP (all P for interaction <0.05). The effect of longer sleep duration on BP components showed no difference in the following subgroups: sex, age, smoking and drinking (all P for interaction >0.05). Conclusion: Compared with a sleep duration of 5-9 h, longer sleep duration (≥10 h) on workdays and non-workdays was associated with high SBP and PP among Chinese hypertensive adults without antihypertensive treatment.

Trends of self-reported sleep duration in Korean Adults: results from the Korea National Health and Nutrition Examination Survey 2007-2015

OBJECTIVE/BACKGROUND

Sleep plays a vital role in maintaining homeostasis and promoting individual health. This study aimed to investigate the trends of sleep duration in Korean adults.

PATIENTS/METHODS

We collected data from individuals who were adults (≥18 years) and participated in three cycles (2007-2009, 2010-2012, and 2013-2015) of the Korea National Health and Nutrition Examination Survey (KNHANES) for the analysis of self-reported sleep duration pattern. A total of 51,545 adults (21,937 men and 29,608 women) were included.

RESULTS

Sleep duration decreased among both men and women from 2007 to 2009 KNHANES to 2013-2015 KNHANES. Sleep duration differed by age group and sex. Moreover, sleep duration declined among middle-aged (30-49 years old) and older (50-64 years old) men and young (18-29 years old) and middle-aged (30-49 years old) women, although not among older and elderly women.

CONCLUSIONS

The young and middle-aged adult groups (18-49 years old) showed a significant decline in sleep duration in the KNHANES 2007-2015.

Association of sleep disturbances with obesity, insulin resistance and the metabolic syndrome

Insufficient sleep, which has become endemic in recent years, has been variably associated with increased risk of obesity, disorders of glucose and insulin homeostasis, and the metabolic syndrome; to a lesser degree, so has excessive sleep. This review summarizes recent epidemiological and pathophysiological evidence linking sleep disturbances (primarily abnormalities of sleep duration) with obesity, insulin resistance, type 2 diabetes and the metabolic syndrome in children and adults.

Sleep Duration and Hypertension: Analysis of > 700,000 Adults by Age and Sex

STUDY OBJECTIVES

The objective of this study was to evaluate the cross-sectional relationship between sleep duration and hypertension in a large, nationally-representative dataset that spans 10 years. This analysis may provide detailed information with high resolution about how sleep duration is related to hypertension and how this differs by demographic group.

METHODS

Data were aggregated from the 2013 Behavioral Risk Factor Surveillance System (n = 433,386) and the combined 2007-2016 National Health Interview Surveys (n = 295,331). These data were collected by the Centers for Disease Control and Prevention from nationally-representative samples. Surveys were combined, and survey-specific weights were used in all analyses. Sleep duration was assessed with the item, "On average, how many hours of sleep do you get in a 24-hour period?" in both surveys. Hypertension was assessed as self-reported history. Covariates were assessed identically in both datasets and included, age (in 5-year groupings), sex, race/ethnicity, and employment status.

RESULTS

In adjusted analyses, compared to 7 hours, increased risk of hypertension was seen among those sleeping ≤ 4 hours (odds ratio [OR] = 1.86, P < .0005), 5 hours (OR = 1.56, P < .0005), 6 hours (OR = 1.27, P < .0005), 9 hours (OR = 1.19, P < .0005), and ≥ 10 hours (OR = 1.41, P < .0005). When stratified by age, sex, and race/ethnicity groups, short sleep was associated with increased risk for all age groups < 70 years, and long sleep (≥ 10 hours only) was associated with risk for all except < 24 years and > 74 years. Findings for short sleep were relatively consistent across all race/ethnicities, although findings for long sleep were less pronounced among Black/African-American and Other/Multiracial groups. A significant sleep by 3-way sleep × age × sex interaction (P < .0005) suggests that the relationship depends on both age and sex. For both men and women, the OR of having hypertension associated with short sleep decreases with increasing age, but there is a higher association between short sleep and hypertension for women, throughout the adult lifespan.

CONCLUSIONS

Both short and long sleep duration are associated with increased hypertension risk across most age groups. The influence of covariates is stronger upon long sleep relationships. Relationships with short sleep were stronger among younger adults and women.

Disparities in Hypertension Among African-Americans: Implications of Insufficient Sleep

PURPOSE OF REVIEW

Sleep deficiency has been proposed as a potential contributor to racial disparities in cardiovascular health. We present contemporary evidence on the unequal burden of insufficient sleep in Blacks/African-Americans and the repercussions for disparate risk of hypertension.

RECENT FINDINGS

The prevalence of insufficient sleep is high and rising and has been recognized as an important cardiovascular risk factor. Presumably due to a constellation of environmental, psychosocial, and individual determinants, these risks appear exacerbated in Blacks/African-Americans, who are more likely to experience short sleep than other ethnic/racial groups. Population-based data suggest that the risk of hypertension associated with sleep deficiency is greater in those of African ancestry. However, there is a paucity of experimental evidence linking short sleep duration to blood pressure levels in African-Americans. Blacks/African-Americans may be more vulnerable to sleep deficiency and to its hypertensive effects. Future research is needed to unequivocally establish causality and determine the mechanism underlying the postulated racial inequalities in sleep adequacy and consequent cardiovascular risk.

National patterns of physician management of sleep apnea and treatment among patients with hypertension

STUDY OBJECTIVES

Sleep apnea is associated with hypertension, and treatment may improve outcomes. We examine national burden of sleep apnea, rates of sleep apnea treatment, and whether racial/ethnic disparities exist among patients with hypertension.

METHODS

Data from the National Ambulatory Medical Care Survey/National Hospital Ambulatory Medical Care Survey (NAMCS/NHAMCS), 2005-2012, were analyzed (N = 417,950). We identified hypertension patient visits where sleep apnea diagnosis or complaint was recorded. Primary outcome measures were sleep study, medication, or behavioral therapy (diet, weight loss, or exercise counseling). We used multivariate logistic regression to examine treatment by demographic/clinical factors.

RESULTS

Among patients with hypertension, sleep apnea was identified in 11.2-per-1,000 visits. Overall, patients with hypertension and a sleep disorder were referred for sleep study in 14.4% of visits, prescribed sleep medication in 11.2% of visits, and offered behavioral therapy in 34.8% of visits. Adjusted analyses show behavioral therapy more likely to be provided to obese patients than normal/overweight (OR = 4.96, 95%CI[2.93-8.38]), but less likely to be provided to smokers than nonsmokers (OR = 0.54, 95%CI[0.32-0.93]). Non-Hispanic blacks were less likely to receive medications than non-Hispanic whites (OR = 0.19, 95% CI[0.06-0.65]).

CONCLUSIONS

In the U.S., sleep apnea were observed in a small proportion of hypertension visits, a population at high-risk for the disorder. One explanation for the low prevalence of sleep apnea observed in this patient population at high risk for the disorder is under-diagnosis of sleep related breathing disorders. Behavioral therapy was underutilized, and non-Hispanic Blacks were less likely to receive medications than non-Hispanic Whites.

Genetic and Environmental Contributions to Sleep Quality and Low Back Pain: A Population-Based Twin Study

OBJECTIVE

The aim of the study was to estimate the extent to which the co-occurrence of poor sleep quality and low back pain is due to the same genetic and/or environmental risk factors or due to a causal association.

METHODS

Cross-sectional data on sleep quality (Pittsburgh Sleep Quality index) and low back pain were collected in a population-based sample of adult twins (N = 2134) registered with the Murcia Twin Registry. Bivariate analysis and structural equation modeling were used.

RESULTS

The phenotypic correlation between sleep quality and low back pain was 0.23 (95% confidence interval [CI] = 0.17-0.28). The best-fitting bivariate model included additive genetic and unique environmental factors. Genetic factors accounted for 26% (95% CI = 10-40) and 34% (95% CI = 25-43) of the variability of low back pain and sleep quality, respectively. The correlation between the genetic factors underlying each trait was rG of 0.33 (95% CI = 0.03-0.66), and this overlap of genetic factors explained 42.5% of the phenotypic correlation. On the other hand, nonshared environmental factors of each variable were only fairly correlated rE of 0.19 (95% CI = 0.06-0.31), although this overlap explained 57.5% of the phenotypic correlation. In addition, twins in monozygotic pairs with poorer sleep quality presented more often with low back pain than their co-twins (ρ^ = 0.25, p < .0001).

CONCLUSIONS

The data are compatible with a causal effect of sleep quality on low back pain (or the reverse effect), because the correlations between the genetic and unique environmental factors for each trait were significant and there was a significant correlation between the monozygotic twins' difference scores. Apart from environmental factors that affect both characteristics, there are many individual-specific events that influence low back pain but differ from those influencing sleep quality.

The effect of sleep duration and sleep quality on hypertension in middle-aged and older Chinese: the Dongfeng-Tongji Cohort Study

OBJECTIVE

To examine the independent and combined associations of sleep duration and sleep quality with hypertension in a middle-aged and older Chinese population.

METHODS

We included 21,912 individuals aged 62.2 years at baseline from September 2008 to June 2010, and they were followed until October 2013. Sleep duration was self-reported and sleep quality was evaluated with questions designed according to the Pittsburgh Sleep Quality Index. Hypertension was defined as blood pressure ≥140/90 mmHg, or self-reported physician diagnosis of hypertension, or self-reported current use of antihypertensive medication.

RESULTS

In the cross-sectional analyses, the odds ratio of hypertension prevalence was significantly elevated (OR = 1.13, 95% CI = 1.03-1.24) in those who slept less than 7 h after adjusting for sex, age, body mass index, midday napping, cigarette smoking and sleep quality. It was particularly evident among males (OR = 1.19, 95% CI = 1.01-1.40) and individuals who were thin (OR = 2.00, 95% CI = 1.01-3.93) with full adjustment. The association was also found for sleep duration of 9∼<10 h after adjusting various covariates (OR = 1.14, 95% CI = 1.04-1.27). In addition, impaired sleep quality was only associated with hypertension in obese individuals (OR = 1.25, 95% CI = 1.02-1.50), not in other subgroups. However, no significant association was detected in any category of sleep duration or sleep quality in all models in the prospective analyses, and the results remained unchanged in the subgroup analyses of sex, age and body mass index.

CONCLUSIONS

The results of this study provide limited support for association of sleep duration and sleep quality with hypertension in middle-aged and older Chinese. Further studies are needed to confirm the results.

Sleep quality, chronotype and metabolic syndrome components in bipolar disorders during the remission period: Results from the FACE-BD cohort

Data on sleep or circadian abnormalities and metabolic disturbances in euthymic bipolar disorders are scarce and based on small sample sizes. The aim of this study was to explore the associations between sleep disturbances, chronotype and metabolic components in a large sample of euthymic patients with bipolar disorders (BD). From 2009 to 2015, 752 individuals with bipolar disorders from the FACE-BD cohort were included and assessed for sleep quality, chronotype and metabolic components. The Structured Clinical Interview for DSM-IV Axis I Disorders (SCID) was used to confirm the diagnosis of BD. Subjective sleep quality was measured with the Pittsburgh Sleep Quality Index and chronotype with the Composite Scale of Morningness. Sociodemographic and clinical characteristics, psychotropic treatment, psychiatric comorbidities and blood samples were collected. In our sample, 22.4% of individuals with BD presented with a metabolic syndrome, 53.7% had sleep disturbances, 25.4% were considered as having an evening chronotype and 12.6% as having a morning chronotype. Independently of potential confounders, euthymic patients with sleep disturbances had a higher abdominal circumference, and patients with evening chronotype had a significantly higher level of triglycerides. There was an association between evening chronotype and an increased atherogenic index of plasma (OR = 4.8, 95%CI = 1.6-14.7). Our findings contribute the scant literature on the relationship between sleep quality, chronotype and cardiometabolic components in euthymic individuals with BD and highlight the need to improve quality of sleep and patient education about healthier sleep-hygiene practices.