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

Association between sleep duration and cardiovascular risk: the EVasCu cross-sectional study

Introduction

Some cardiovascular risk markers have been associated with alterations in sleep duration in different populations; however, there is little evidence in a healthy population.

Aim

The aim of the present study was to analyze the associations between sleep duration and cardiovascular risk biomarkers, including advanced glycation end-products (AGEs) measured by skin autofluorescence (SAF), maximum carotid intima-media thickness (IMTMax), aortic pulse wave velocity (a-PWV), pulse pressure (PP), and low-density lipoprotein cholesterol (LDL-C), in healthy adults (EVasCu study).

Methodology

The EVasCu study included 390 participants. Simple and multiple linear regressions were performed between sleep duration and cardiovascular risk markers. ANOVA analysis and ANCOVA analysis adjusted for various covariates were then performed after categorizing sleep into 6 h, 6-8 h, and >8 h.

Results

296 participants were included in the analyses (43.97 ± 12.60 years, 63.9% female). Simple linear regressions showed an inverse association between sleep duration and SAF, IMTMax, aPWV and PP. However, in the multiple linear regression with all the covariates, the statistical significance was lost. For its part, in the ANOVA analyses, sleep duration was also associated with the same parameters, but when performing the fully adjusted ANCOVA analyses, the statistical significance for SAF was maintained (p = 0.015), obtaining a difference of 0.223 arbitrary units (p = 0.017) when comparing the group <6 h vs. > 8 h. Finally, there was no association for LDL-C.

Conclusion

An inverse association was found between sleep duration and APS, which is considered a marker of cardiovascular risk. Although prospective studies are needed, it is suggested that insufficient sleep may increase cardiovascular risk, which could be a key factor in future public health policies to promote health and prevent CVD.

Baseline coronary artery stenosis severity is an independent predictor of subsequent poor sleep quality in patients with acute coronary syndrome

AIM

To investigate the relationship between coronary artery lesion severity determined using the baseline SYNTAX score and sleep problems that might occur after discharge determined using the Pittsburgh Sleep Quality Index (PSQI).

METHODS

This prospective study included patients with first acute coronary syndrome (ACS) who underwent percutaneous coronary angiography between February 2019 and August 2019. The severity of coronary artery stenosis was classified according to coronary angiography and SYNTAX scores. Patients were grouped as those with a SYNTAX score of ≤22 and >22. Sleep quality after discharge was classified according to the PSQI. PSQI ≤5 represented good sleep quality, and PSQI >5 represented poor sleep quality. Univariate and multivariate logistic regression was used to investigate the relationship between sleep quality and coronary artery stenosis severity.

RESULTS

A total of 424 patients were included in the study. Of these, 294 (69.34%) had a SYNTAX score of ≤22 and 130 (30.66%) had a SYNTAX score of >22. The mean age of all patients was 60.37 ± 12.23 years, 59.69 ± 11.85 years in the SYNTAX ≤22 groups and 61.90 ± 12.98 years in the SYNTAX >22 group (P = 0.086). The majority (78.54%) of the patients were male and there was no significant difference between the SYNTAX ≤22 group and the SYNTAX >22 group in terms of sex distribution (P = 0.383). According to the univariate logistic regression analysis, age (P = 0.014), diabetes (P = 0.027), left ventricular ejection fraction (P = 0.001), estimated glomerular filtration rate (P = 0.039), creatine kinase MB (P = 0.040) and SYNTAX scores (P < 0.001) were significantly associated with high PSQI global scores (>5). However, according to the multivariate logistic regression analysis results, high (>22) SYNTAX scores were the only factor independently associated with the high (>5) PSQI global scores [odds ratio, 3.477; 95% confidence interval (CI), (2.190-5.522); P < 0.001]. Complete revascularization group had significantly higher sleep latency and sleep duration time, sleep efficiency and the percentage of patients with PSQI global score of ≤5 than the incomplete revascularization group (P < 0.001 for all).

CONCLUSION

Among patients with ACS, those with high SYNTAX scores should be monitored more carefully for sleep disorders that may occur later.

Insomnia and risk of mortality in older adults

Existing evidence linking insomnia to all-cause mortality in older individuals remains inconclusive. We conducted a retrospective study of a large cohort of veterans aged 65-80 years old identified from the Corporate Data Warehouse, a large data repository derived from the Veterans Health Administration integrated medical records. Veterans' enrollees with and without International Classification of Diseases, Ninth and Tenth Revision, codes corresponding to insomnia diagnosis between 1 January 2010 and 30 March 2019 were assessed for eligibility. The primary outcome was all-cause mortality. A total of 36,269 veterans, 9584 with insomnia and 26,685 without insomnia, were included in the analysis. Baseline mean (SD) age was 72.6 (4.2) years. During a mean follow-up of 6.0 (2.9) years of the propensity score matched sample, the mortality rate was 34.8 [95% confidence interval: 33.2-36.6] deaths per 1000 person-years among patients with insomnia compared with 27.8 [95% confidence interval: 26.6-29.1] among patients without insomnia. In a Cox proportional hazards model, insomnia was significantly associated with higher mortality (hazard ratio: 1.39; [95% confidence interval: 1.27-1.52]). Patients with insomnia also had a higher risk of non-fatal cardiovascular events (hazard ratio: 1.21; [95% confidence interval: 1.06-1.37]). Secondary stratified analyses by sex, race, ethnicity and hypertension showed no evidence of effect modification. A higher risk of mortality (hazard ratio: 1.51; [95% confidence interval: 1.33-1.71]) was observed when depression was present compared with absent (hazard ratio: 1.26; [95% confidence interval: 1.12-1.44]; p = 0.02). In this cohort study, insomnia was associated with increased risk-adjusted mortality and non-fatal cardiovascular events in older individuals.

Association of resistance training and moderate-to-vigorous physical activity with clinical outcomes in men with airflow limitation: a nationwide population-based study

Aerobic moderate-to-vigorous physical activity (MVPA) is recommended for individuals with chronic diseases. However, the association between resistance training (RT) in addition to moderate to vigorous physical activity (MVPA) and sleep duration, as well as respiratory symptoms, in patients with chronic obstructive pulmonary disease has not been thoroughly investigated. This population-based cross-sectional study used data from the Korea National Health and Nutrition Examination Survey between 2014 and 2019. A total of 61,754 individuals were identified and men with airflow limitation (FEV1/FVC < 0.7) who engaged in aerobic MVPA were selected (n = 794). Weighted percentages and odds ratio (OR) of sleep problems (≤ 5 or ≥ 9 h), chronic cough, and chronic sputum were estimated. A multivariate-adjusted complex sample logistic regression model was used to calculate ORs and 95% confidence intervals (CI). Subgroup analyses were conducted using the forced expiratory volume (FEV1) % of the predicted value (%pred) ≥ 80 vs. < 80. The percentages of sleep problems, chronic cough, and chronic sputum production were lower in men who underwent aerobic MVPA + RT than in those who underwent aerobic MVPA alone. The multivariable-adjusted OR of sleep problems was 0.44 (95% CI 0.25-0.77) in individuals undergoing aerobic MVPA + RT compared to aerobic MVPA alone. The ORs of chronic cough and sputum were 0.35 (95% CI 0.13-0.94) and 0.51 (95% CI 0.30-0.87), respectively. These associations were only significant in individuals with FEV1 < 80% pred. Compared with aerobic MVPA alone, aerobic MVPA + RT was associated with appropriate sleep duration and a decrease in chronic cough and sputum in male with airflow limitation. This was more pronounced in individuals with a FEV1 < 80% pred.

Insomnia nosology: a systematic review and critical appraisal of historical diagnostic categories and current phenotypes

Insomnia nosology has significantly evolved since the Diagnostic and Statistical Manual (DSM)-III-R first distinguished between 'primary' and 'secondary' insomnia. Prior International Classification of Sleep Disorders (ICSD) nosology 'split' diagnostic phenotypes to address insomnia's heterogeneity and the DSM nosology 'lumped' them into primary insomnia, while both systems assumed causality for insomnia secondary to health conditions. In this systematic review, we discuss the historical phenotypes in prior insomnia nosology, present findings for currently proposed insomnia phenotypes based on more robust approaches, and critically appraise the most relevant ones. Electronic databases PsychINFO, PubMED, Web of Science, and references of eligible articles, were accessed to find diagnostic manuals, literature on insomnia phenotypes, including systematic reviews or meta-analysis, and assessments of the reliability or validity of insomnia diagnoses, identifying 184 articles. The data show that previous insomnia diagnoses lacked reliability and validity, leading current DSM-5-TR and ICSD-3 nosology to 'lump' phenotypes into a single diagnosis comorbid with health conditions. However, at least two new, robust insomnia phenotyping approaches were identified. One approach is multidimensional-multimethod and provides evidence for self-reported insomnia with objective short versus normal sleep duration linked to clinically relevant outcomes, while the other is multidimensional and provides evidence for two to five clusters (phenotypes) based on self-reported trait, state, and/or life-history data. Some approaches still need replication to better support whether their findings identify true phenotypes or simply different patterns of symptomatology. Regardless, these phenotyping efforts aim at improving insomnia nosology both as a classification system and as a mechanism to guide treatment.

Sleep Duration Is Associated With Subclinical Carotid Plaque Burden

BACKGROUND

Sleep duration is associated with stroke risk and is 1 of 8 essential components of cardiovascular health according to the American Heart Association. As stroke disproportionately burdens Black and Hispanic populations in the United States, we hypothesized that long and short sleep duration would be associated with greater subclinical carotid atherosclerosis, a precursor of stroke, in the racially and ethnically diverse NOMAS (Northern Manhattan Study).

METHODS

NOMAS is a study of community-dwelling adults. Self-reported nightly sleep duration and daytime sleepiness were collected between 2006 and 2011. Carotid plaque presence, total plaque area, and intima-media thickness were measured by ultrasound between 1999 and 2008. Linear and logistic regression models examined the cross-sectional associations of sleep duration groups (primary exposure) or daytime sleepiness (secondary exposure) with measures of carotid atherosclerosis. Models adjusted for age, time between ultrasound and sleep data collection, sex, race and ethnicity, education, health insurance, smoking, alcohol use, physical activity, body mass index, hypertension, diabetes, hypercholesterolemia, and cardiac disease.

RESULTS

The sample (n=1553) had a mean age of 64.7±8.5 years and was 61.9% female, 64.8% Hispanic, and 18.2% non-Hispanic Black. Of the sample, 55.6% had carotid plaque, 22.3% reported nightly short sleep (<7 hours), 66.6% intermediate sleep (≥7 and <9 hours), and 11.1% had long sleep (≥9 hours). Compared with intermediate sleep, long sleep was associated with greater odds of carotid plaque presence relative to plaque absence (odds ratio, 1.6 [95% CI, 1.1-2.4]) and larger total plaque area (odds ratio, 1.4 [95% CI, 1.0-1.9]) after full covariate adjustment. Short sleep and daytime sleepiness were not significantly associated with any carotid measures.

CONCLUSIONS

The association between long sleep and subclinical carotid atherosclerosis may explain prior associations between long sleep and stroke.

The relationship between sleep duration and arterial stiffness: A meta-analysis

Chronically short (<7 h) and long (>9 h) sleep duration may increase cardiovascular disease (CVD) risk relative to the recommended sleep duration (7-9 h). The objective of this study was to evaluate the effects of short and long sleep duration on arterial stiffness, a marker of CVD risk, in adults. Eleven cross-sectional studies were reviewed with a total sample size of 100,050 participants (64.5% male). Weighted mean differences (WMD) and 95% confidence intervals (95% CI) were calculated and pooled using random effects models, and standardized mean differences (SMD) were calculated to determine effect size magnitude. Compared to the recommended sleep duration, both short (WMD = 20.6 cm/s, 95% confidence intervals (CI): 13.8-27.4 cm/s, SMD = 0.02) and long sleep duration (WMD = 33.6 cm/s, 95% CI: 20.0-47.2 cm/s, SMD = 0.79) were associated with higher (detrimental) pulse wave velocity (PWV). The associations between short sleep and higher PWV in adults with cardiometabolic disease, and long sleep and higher PWV in older adults, were also significant in sub-group analysis. These findings indicate short and long sleep duration may contribute to subclinical CVD.

All-cause and major-cause mortality associated with sleep latency in the Korean Genome and Epidemiology Study (KoGES): a population-based prospective cohort study

BACKGROUND

The all-cause and cause-specific mortality risk associated with sleep latencies in the general adult population is unknown. We aimed to investigate the association of habitual prolonged sleep latency with long-term all-cause and cause-specific mortality in adults.

METHODS

The Korean Genome and Epidemiology Study (KoGES) is a population-based prospective cohort study comprising community-dwelling men and women aged 40-69 years from Ansan, South Korea. The cohort was studied bi-annually from April 17, 2003, to Dec 15, 2020, and the current analysis included all individuals who completed the Pittsburgh Sleep Quality Index (PSQI) questionnaire between April 17, 2003, and Feb 23, 2005. The final study population comprised 3757 participants. Data were analysed from Aug 1, 2021, to May 31, 2022. The main exposure was sleep latency groups based on the PSQI questionnaire: fell asleep in 15 min or less, fell asleep in 16-30 min, occasional prolonged sleep latency (fell asleep in >30 min once or twice a week in the past month) and habitual prolonged sleep latency (fell asleep in >60 min more than once a week or fell asleep in >30 min ≥3 times a week, or both) in the past month at baseline. Outcomes were all-cause and cause-specific (cancer, cardiovascular disease, and other causes) mortality reported during the 18-year study period. Cox proportional hazards regression models were used to examine the prospective relationship between sleep latency and all-cause mortality, and competing risk analyses were done to investigate the association of sleep latency with cause-specific mortality.

FINDINGS

During a median follow-up of 16·7 years (IQR 16·3-17·4), 226 deaths were reported. After adjusting for demographic characteristics, physical characteristics, lifestyle factors, chronic conditions, and sleep variables, self-reported habitual prolonged sleep latency was associated with an increased risk of all-cause mortality (hazard ratio [HR] 2·22, 95% CI 1·38-3·57) compared to the reference group (those who fell asleep in 16-30 min). In the fully adjusted model, habitual prolonged sleep latency was associated with a more than doubled risk of dying from cancer compared to the reference group (HR 2·74, 95% CI 1·29-5·82). No significant association was observed between habitual prolonged sleep latency and deaths from cardiovascular disease and other causes.

INTERPRETATION

In this population-based prospective cohort study, habitual prolonged sleep latency was independently associated with an increased risk of all-cause and cancer-specific mortality in adults (independently of demographic characteristics, lifestyle factors, chronic morbidities, and other sleep variables). Although further studies are warranted to investigate the causality of the relationship, strategies or interventions to prevent habitual prolonged sleep latencies might enhance longevity in the general adult population.

FUNDING

Korea Centers for Disease Control and Prevention.

Combined Effects of Obesity and Dyslipidaemia on the Prevalence of Diabetes Amongst Adults Aged ≥45 Years: Evidence from a Nationally Representative Cross-Sectional Study

Objectives: This study aimed to explore the combined effects of different types of obesity and dyslipidaemia on the prevalence of diabetes in middle-aged and elderly residents. Methods: Data were obtained from the 2015 China Health and Retirement Longitudinal Studydatabase, and 5023 valid participants were included after excluding those with missing data. A Chi-square test was used to test the difference in the prevalence of diabetes between the groups. Binary logistic regression was used to analyse the relationship between different types of obesity combined with dyslipidaemia and the prevalence of diabetes. Results: Multivariate logistic regression analysis showed that, compared with those with a body mass index <24/ortholiposis, the subgroup with systemic obesity/dyslipidaemia had 4.37 times the risk of diabetes (OR = 4.37, 95% CI = 2.36−8.10, p < 0.001). In addition, compared with those with a normal waist circumference (WC)/ortholiposis, the subgroup with abdominal obesity/dyslipidaemia had 3.58 times the risk of diabetes (OR = 3.58, 95% CI = 2.49−5.13, p < 0.001). Conclusions: The coexistence of obesity and dyslipidaemia can significantly increase the risk of diabetes, suggesting that the strict control of weight, WC and lipid level is beneficial to the prevention of diabetes.

Identification of Potential Diagnostic Biomarkers From Circulating Cells During the Course of Sleep Deprivation-Related Myocardial Infarction Based on Bioinformatics Analyses

Background

Myocardial infarction (MI) is the leading cause of death from non-infectious diseases worldwide and results in rapid deterioration due to the sudden rupture of plaques associated with atherosclerosis, a chronic inflammatory disease. Sleep is a key factor that regulates immune homeostasis of the body. The imbalance in circulating immune cells caused by sleep deprivation (SD) may represent a risk factor leading to the rapid deterioration of plaques and MI. Therefore, it is of profound significance to identify diagnostic biomarkers for preventing SD-related MI.

Methods

In the present study, we identified coexpressed differentially expressed genes (co-DEGs) between peripheral blood mononuclear cells from MI and SD samples (compared to controls) from a public database. LASSO regression analysis was applied to identify significant diagnostic biomarkers from co-DEGs. Moreover, receiver operating characteristic (ROC) curve analysis was performed to test biomarker accuracy and diagnostic ability. We further analyzed immune cell enrichment in MI and SD samples using the CIBERSORT algorithm, and the correlation between biomarkers and immune cell composition was assessed. We also investigated whether diagnostic biomarkers are involved in immune cell signaling pathways in SD-related MI processes.

Results

A total of 10 downregulated co-DEGs from the sets of MI-DEGs and SD-DEGs were overlapped. After applying LASSO regression analysis, SYTL2, KLRD1, and C12orf75 were selected and validated as diagnostic biomarkers using ROC analysis. Next, we found that resting NK cells were downregulated in both the MI samples and SD samples, which is similar to the changes noted for SYTL2. Importantly, SYTL2 was strongly positively correlated not only with resting NK cells but also with most genes related to NK cell markers in the MI and SD datasets. Moreover, SYTL2 was highly associated with genes in NK cell signaling pathways, including the MAPK signaling pathway, cytotoxic granule movement and exocytosis, and NK cell activation. Furthermore, GSEA and KEGG analyses provided evidence that the DEGs identified from MI samples with low vs. high SYTL2 expression exhibited a strong association with the regulation of the immune response and NK cell-mediated cytotoxicity.

Conclusion

In conclusion, SYTL2, KLRD1, and C12orf75 represent potential diagnostic biomarkers of MI. The association between SYTL2 and resting NK cells may be critically involved in SD-related MI development and occurrence.

Association between insomnia and subclinical atherosclerosis among Chinese steelworkers: a cross-sectional survey

Background

Insomnia is a common prevalent sleep disorder. Difficulty maintaining sleep or poor in quality in insomnia caused by disrupted or misaligned circadian rhythms may play an important role in the development of atherosclerosis. This study aimed to examine the association between insomnia and subclinical atherosclerosis in Chinese steelworkers.

Methods

A total of 3240 subjects from a large enterprise located in northern China were included in this study. The Athens Insomnia Scale (AIS) was used to assess the status of insomnia. Subclinical atherosclerosis was evaluated using ultrasonographic measurements of carotid plaque. Multivariable logistic regression was used to identify association between insomnia and carotid atherosclerosis.

Results

The overall prevalence of insomnia and carotid plaque were 35.3 and 31.7% in the study population. Compared with non-insomnia workers, significantly increased odds of carotid plaque were observed among insomnia workers after adjusting for potential confounders, odds ratio (OR) = 1.38, 95% confidence interval (CI): 1.17 to 1.63. Exposure to current shift work and insomnia simultaneously can significantly elevated the odds of carotid plaque.

Conclusion

Insomnia is associated with elevated odds of carotid atherosclerosis in male steelworkers. Insomnia problems of workers should receive further attention in occupational worker health interventions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13690-022-00834-1.

The Association Between Insomnia and Atherosclerosis: A Brief Report

AIM

The objective of the study was to clarify the occurrence of atherosclerosis in patients with insomnia.

METHODS

A total of 60 patients with insomnia and 58 patients in a control group were selected to measure blood glucose, blood lipids and other biochemical and physiological indicators. Brachial-ankle pulse wave velocity (baPWV) was measured to assess arterial stiffness, and color Doppler ultrasound was used to examine carotid artery intima-media thickness (CIMT) and plaque incidence. These indicators were used to determine the occurrence and degree of carotid atherosclerosis, and to compare the differences between the two groups.

RESULTS

While there was no significant difference in biochemical or physiological indicators between the two groups (P > 0.05), the baPWV, CIMT, and incidence of carotid plaque in the insomnia group were higher than the control group. In addition, the baPWV, CIMT, and incidence of carotid plaque in the chronic insomnia group were higher than that in the short-term insomnia group. Multiple linear regression analysis was carried out to analyze the effects of insomnia, systolic blood pressure, blood glucose, triglycerides, cholesterol, BMI, age and low-density lipoprotein on atherosclerosis. The results showed that increased CIMT was significantly correlated with insomnia in atherosclerosis group (R²=0.27 on the left, R²=0.37 on the right, P < 0.001).

CONCLUSION

Insomnia correlated with increased arterial stiffness and carotid atherosclerosis, and as the duration of insomnia prolongs, the correlation between them became more obvious.

Potential Effect of the Circadian Clock on Erectile Dysfunction

The circadian rhythm is an internal timing system, which is generated by circadian clock genes. Because the circadian rhythm regulates numerous cellular, behavioral, and physiological processes, organisms have evolved with intrinsic biological rhythms to adapt the daily environmental changes. A variety of pathological events occur at specific times, while disturbed rhythms can lead to metabolic syndrome, vascular dysfunction, inflammatory disorders, and cancer. Therefore, the circadian clock is considered closely related to various diseases. Recently, accumulated data have shown that the penis is regulated by the circadian clock, while erectile function is impaired by an altered sleep-wake cycle. The circadian rhythm appears to be a novel therapeutic target for preventing and managing erectile dysfunction (ED), although research is still progressing. In this review, we briefly summarize the superficial interactions between the circadian clock and erectile function, while focusing on how disturbed rhythms contribute to risk factors of ED. These risk factors include NO/cGMP pathway, atherosclerosis, diabetes mellitus, lipid abnormalities, testosterone deficiency, as well as dysfunction of endothelial and smooth muscle cells. On the basis of recent findings, we discuss the potential role of the circadian clock for future therapeutic strategies on ED, although further relevant research needs to be performed.

Associations of Insomnia With Hypertension and Coronary Artery Disease Among Patients With Type 2 Diabetes Mellitus

Purpose: This study aimed to determine whether insomnia is associated with hypertension (HBP) and coronary artery disease (CAD) in a hospital-based sample of patients with type 2 diabetes mellitus (T2DM).

Methods: Our present study included 354 patients with T2DM. According to the diagnostic criteria of insomnia, the participants were assigned to three groups based on the duration of T2DM and insomnia diagnosis. Patients with T2DM alone were placed in group A; patients with T2DM longer than insomnia were placed in group B; and patients with insomnia longer than T2DM were placed in group C. Medical history was collected from all the patients in detail. Besides, the participants underwent thorough physical examinations and laboratory measurements. Propensity score matching (PSM) was applied to evaluate the associations of insomnia with HBP and CAD. The univariate and multivariate logistic regression analysis was used to explore whether insomnia was a risk factor for HBP and CAD in patients with T2DM.

Results: Of 354 patients, 225 patients were included in group A, 62 patients were included in group B, and 67 patients were included in group C. Compared with groups B and C, group A showed a lower prevalence of HBP and CAD (p < 0.05). In addition, compared with group B, group C showed no difference in the prevalence of HBP and CAD (p > 0.05). After PSM was performed, groups B and C had a higher prevalence of HBP and CAD (p < 0.05) than group A with no significant difference between groups B and C (p > 0.05). In the univariate and multivariate logistic regression analysis, insomnia was a risk factor for HBP [univariate: odds ratio (OR) = 3.376, 95% CI 2.290–6.093, p < 0.001; multivariate: OR = 2.832, 95% CI 1.373–5.841, p = 0.005] and CAD (univariate: OR = 5.019, 95% CI 3.148–8.001, p < 0.001; multivariate: OR = 5.289, 95% CI 2.579–10.850, p < 0.001).

Conclusion: T2DM combined with insomnia was related to HBP and CAD and insomnia was a risk factor for HBP and CAD in patients with T2DM. However, larger, prospective studies are required to confirm our findings.

Hypothalamic-pituitary-adrenal (HPA) axis response to exogenous corticotropin-releasing hormone (CRH) is attenuated in men with chronic insomnia

Although insomnia is by far the most common sleep disorder, our understanding of its neurobiology is limited. Insomnia, particularly when associated with objective sleep disturbance, has been associated with activation of the hypothalamic-pituitary-adrenal axis. The objective of this experimental study was to compare the response of the hypothalamic-pituitary-adrenal axis to ovine corticotropin-releasing hormone, a stress test, in men with insomnia versus controls. Circulating adrenocorticotropic hormone and cortisol levels were assayed before (-30 min, -15 min), at (0 min) and after (+5 min, +15 min, +30 min, +60 min, +90 min, +120 min) exogenous ovine corticotropin-releasing hormone administration in 23 men (11 insomnia, 12 controls), who underwent four consecutive nights of in-lab polysomnography. Men with insomnia compared with controls demonstrated markedly and significantly shorter total sleep time (368.4 ± 8.99 min versus 411.61 ± 8.61 min; p < 0.01) and lower sleep efficiency (76.77 ± 1.80% versus 86.04 ± 1.72%; p < 0.01) on polysomnography, and showed decreased adrenocorticotropic hormone and cortisol levels after ovine corticotropin-releasing hormone administration. Adrenocorticotropic hormone levels at 15 min and 30 min were significantly lower in men with insomnia than in controls (p < 0.05). Similarly, the peak levels of cortisol at +60 min, and the total and net area under the curve levels of this hormone were significantly lower in men with insomnia than controls (all p < 0.01). Adrenocorticotropic hormone and cortisol response to ovine corticotropin-releasing hormone administration was attenuated in men with insomnia associated with objective sleep disturbance, suggesting that objectively defined insomnia subtypes have a disrupted hypothalamic-pituitary-adrenal axis function and highlight the need to develop treatments targeting the underlying hypothalamic-pituitary-adrenal axis dysregulation.

Insomnia with objective short sleep duration is associated with cognitive impairment: a first look at cardiometabolic contributors to brain health

STUDY OBJECTIVES

Insomnia with objective short sleep duration has been previously associated with adverse cardiometabolic health outcomes as well as poorer cognitive performance in otherwise noncognitively impaired adults. However, studies demonstrating an increased prevalence of cognitive impairment (CI) in this insomnia phenotype are lacking.

METHODS

We analyzed data from Penn State Adult Cohort (N = 1,524; 48.9 ± 13.4 years; 53.4% women). Self-reported sleep difficulty was defined as normal sleep (n = 899), poor sleep (n = 453), and chronic insomnia (n = 172). Objective short sleep duration was defined as less than 6-h of sleep, based on in-lab, 8-h polysomnography. CI (n = 155) and possible vascular cognitive impairment (pVCI, n = 122) were ascertained using a comprehensive neuropsychological battery. Analyses adjusted for age, sex, race, education, body mass index, apnea/hypopnea index, smoking, alcohol, psychoactive medication, and mental and physical health problems.

RESULTS

Participants who reported poor sleep or chronic insomnia and slept objectively less than 6 hours were associated with a 2-fold increased odds of CI (OR = 2.06, 95% confidence limits [CL] = 1.15-3.66 and OR = 2.18, 95% CL = 1.07-4.47, respectively) and of pVCI (OR = 1.94, 95% CL = 1.01-3.75 and OR = 2.33, 95% CL = 1.07-5.06, respectively). Participants who reported poor sleep or chronic insomnia and slept objectively more than 6 hours were not associated with increased odds of either CI (OR = 0.72, 95% CL = 0.30-1.76 and OR = 0.75, 95% CL = 0.21-2.71, respectively) or pVCI (OR = 1.08, 95% CL = 0.42-2.74 and OR = 0.76, 95% CL = 0.16-3.57, respectively).

CONCLUSIONS

Insomnia with objective short sleep duration is associated with an increased prevalence of CI, particularly as it relates to cardiometabolic health (i.e. pVCI). These data further support that this insomnia phenotype may be a more biologically severe form of the disorder associated with cardiovascular, cerebrovascular, and neurocognitive morbidity.

Effects of long sleep time and irregular sleep-wake rhythm on cognitive function in older people

Sleep disturbances and cognitive decline are common in older adults. We aimed to investigate the effects of the total sleep time (TST) and sleep–wake rhythm on executive function and working memory in older adults. In 63 older participants, we measured the TST, wake after sleep onset (WASO), and sleep timing (midpoint between bedtime and wake-up time) using actigraphy. Executive function was evaluated with the trail making test B (TMT-B) and Wisconsin card sorting test (WCST). The number of back task (N-back task) was used to measure working memory. Participants with a TST ≥ 8 h had a significantly lower percentage of correct answers (% correct) on the 1-back task than those with a TST < 8 h. The % correct on the 1-back task was significantly correlated with the TST, WASO, and sleep timing. Multiple regression analyses revealed that the TST and sleep timing were significant factors of the % correct on the 1-back task. The TMT-B score was significantly correlated with the sleep timing. Category achievement on the WCST was significantly correlated with the standard deviation of the sleep timing. Therefore, a long sleep time and an irregular sleep–wake rhythm could have adverse effects on executive function and working memory in older people.

On the Association Between Sleep Quality and Arterial Stiffness: A Population Study in Community-Dwelling Older Adults Living in Rural Ecuador (The Atahualpa Project)

STUDY OBJECTIVES

Evidence of an association between atherosclerosis and sleep quality is limited and has not been studied in remote rural settings, where living conditions are different than in urban centers. We aimed to assess the relationship between the aortic pulse wave velocity (PWV) and sleep quality in older adults living in rural Ecuador.

METHODS

Atahualpa residents aged 60 years or older identified during door-to-door surveys, who consented to participate, underwent face-to-face interviews with the Pittsburgh Sleep Quality Index (PSQI) to assess sleep quality. Aortic PWV determinations were performed for arterial stiffness estimation (as a surrogate of atherosclerosis).

RESULTS

A total of 303 individuals were included (mean age: 70.3 ± 7.8 years; 59% women). Univariate logistic regression showed a significant association between the aortic PWV and poor sleep quality (odds ratio [OR] 1.22; 95% confidence interval [CI] 1.07-1.39; P = .003). A multivariate logistic regression model, adjusted for demographics, cardiovascular risk factors, oily fish intake and psychological distress showed a significant association between increased PWV and poor sleep quality (OR 1.59; 95% CI 1.12-2.25; P = .009). Similar significance was noted when the model was adjusted for neuroimaging signatures of cerebral small-vessel disease and stroke (OR 1.47; 95% CI 1.07-2.03; P = .019).

CONCLUSIONS

This study shows a significant independent association between the aortic PWV and poor sleep quality in older adults living in rural Ecuador. Results provide more insights into the relevance of the impact of sleep disorders on cardiovascular diseases.

CLINICAL TRIAL REGISTRATION

The Atahualpa Project has been registered at ClinicalTrials.gov. The identifier number is NCT01627600, and the date was: 10/02/2012.

CITATION

Del Brutto OH, Mera RM, Peñaherrera E, Costa AF, Peñaherrera R, Castillo PR. On the association between sleep quality and arterial stiffness: a population study in community-dwelling older adults living in rural ecuador (the atahualpa project). J Clin Sleep Med. 2019;15(8):1101-1106.

Broken sleep predicts hardened blood vessels

Why does poor-quality sleep lead to atherosclerosis? In a diverse sample of over 1,600 individuals, we describe a pathway wherein sleep fragmentation raises inflammatory-related white blood cell counts (neutrophils and monocytes), thereby increasing atherosclerosis severity, even when other common risk factors have been accounted for. Improving sleep quality may thus represent one preventive strategy for lowering inflammatory status and thus atherosclerosis risk, reinforcing public health policies focused on sleep health.

Why does poor quality sleep correlate with cardiovascular disease? A large population-based study suggests that fragmented sleep contributes to atherosclerosis in humans by increasing inflammatory-related activity of white blood cells.

Unique transcriptional signatures of sleep loss across independently evolved cavefish populations

Animals respond to sleep loss with compensatory rebound sleep, and this is thought to be critical for the maintenance of physiological homeostasis. Sleep duration varies dramatically across animal species, but it is not known whether evolutionary differences in sleep duration are associated with differences in sleep homeostasis. The Mexican cavefish, Astyanax mexicanus, has emerged as a powerful model for studying the evolution of sleep. While eyed surface populations of A. mexicanus sleep approximately 8 hr each day, multiple blind cavefish populations have converged on sleep patterns that total as little as 2 hr each day, providing the opportunity to examine whether the evolution of sleep loss is accompanied by changes in sleep homeostasis. Here, we examine the behavioral and molecular response to sleep deprivation across four independent populations of A. mexicanus. Our behavioral analysis indicates that surface fish and all three cavefish populations display robust recovery sleep during the day following nighttime sleep deprivation, suggesting sleep homeostasis remains intact in cavefish. We profiled transcriptome-wide changes associated with sleep deprivation in surface fish and cavefish. While the total number of differentially expressed genes was not greater for the surface population, the surface population exhibited the highest number of uniquely differentially expressed genes than any other population. Strikingly, a majority of the differentially expressed genes are unique to individual cave populations, suggesting unique expression responses are exhibited across independently evolved cavefish populations. Together, these findings suggest sleep homeostasis is intact in cavefish despite a dramatic reduction in overall sleep duration.

Daridorexant, a new dual orexin receptor antagonist, in elderly subjects with insomnia disorder

Objective

To assess the dose-response of daridorexant, a new dual orexin receptor antagonist, on wake after sleep onset (WASO).

Methods

Elderly (≥65 years) participants (n = 58) with insomnia were randomly allocated (Latin square design) to receive 5 treatments (5, 10, 25, and 50 mg daridorexant and placebo) during 5 treatment periods, each consisting of 2 treatment nights followed by a 5- to 12-day washout period. Main efficacy endpoints were the absolute change from baseline in WASO (primary) and latency to persistent sleep (LPS; secondary) to days 1 and 2 (mean of 2 treatment nights assessed by polysomnography) in each period. Safety and tolerability were also assessed.

Results

Of 58 participants included, 67% were female, and the median age was 69 years (range 65–85 years). WASO and LPS were dose-dependently reduced from baseline to days 1 and 2 after daridorexant administration (multiple comparison procedure modeling, p < 0.0001 and p = 0.004, respectively); reductions were statistically significant for doses ≥10 mg compared with placebo (WASO: −32.0, −45.1, −61.4 minutes; LPS: −44.9, −43.8, −45.4 minutes for 10, 25, and 50 mg, respectively, p ≤ 0.025). Treatment-emergent adverse events were similar for daridorexant and placebo; the most frequent were fatigue, nasopharyngitis, gait disturbance, and headache (≤7% in any group).

Conclusions

Daridorexant was well tolerated. Dose-dependent improvements in WASO and LPS were statistically significant (dose range 10–50 mg) in elderly people with insomnia disorder.

ClinicalTrials.gov identifier:

NCT02841709.

Classification of evidence

This study provides Class I evidence that, for elderly people with insomnia, daridorexant reduced WASO.

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.

Effect of wearables on sleep in healthy individuals: a randomized crossover trial and validation study

STUDY OBJECTIVES

The purpose of this study was to determine whether a wearable sleep-tracker improves perceived sleep quality in healthy participants and to test whether wearables reliably measure sleep quantity and quality compared with polysomnography.

METHODS

This study included a single-center randomized crossover trial of community-based participants without medical conditions or sleep disorders. A wearable device (WHOOP, Inc.) was used that provided feedback regarding sleep information to the participant for 1 week and maintained sleep logs versus 1 week of maintained sleep logs alone. Self-reported daily sleep behaviors were documented in sleep logs. Polysomnography was performed on 1 night when wearing the wearable. The Patient-Reported Outcomes Measurement Information System sleep disturbance sleep scale was measured at baseline, day 7 and day 14 of study participation.

RESULTS

In 32 participants (21 women; 23.8 ± 5 years), wearables improved nighttime sleep quality (Patient-Reported Outcomes Measurement Information System sleep disturbance: B = -1.69; 95% confidence interval, -3.11 to -0.27; P = .021) after adjusting for age, sex, baseline, and order effect. There was a small increase in self-reported daytime naps when wearing the device (B = 3.2; SE, 1.4; P = .023), but total daily sleep remained unchanged (P = .43). The wearable had low bias (13.8 minutes) and precision (17.8 minutes) errors for measuring sleep duration and measured dream sleep and slow wave sleep accurately (intraclass coefficient, 0.74 ± 0.28 and 0.85 ± 0.15, respectively). Bias and precision error for heart rate (bias, -0.17%; precision, 1.5%) and respiratory rate (bias, 1.8%; precision, 6.7%) were very low compared with that measured by electrocardiogram and inductance plethysmography during polysomnography.

CONCLUSIONS

In healthy people, wearables can improve sleep quality and accurately measure sleep and cardiorespiratory variables.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Assessment of Sleep by WHOOP in Ambulatory Subjects; Identifier: NCT03692195.

Sleep and cardiovascular disease: Emerging opportunities for psychology

Sleep disturbances and disorders have been implicated in cardiovascular morbidity and mortality. Converging evidence suggests that psychosocial factors that confer risk or resilience to cardiovascular disease (CVD) are also related to sleep. Profound differences in sleep among racial/ethnic minorities compared with non-Hispanic Whites in the United States suggest that sleep, and its interplay with psychosocial factors, may contribute to observed disparities in CVD and in health and functioning more broadly. Less understood is the extent to which sleep and psychosocial factors interact to influence the pathophysiology and clinical course of CVD. This article reviews observational and experimental evidence linking short sleep duration and insomnia, both modifiable sleep disturbances, to CVD, including key physiological mechanisms. Also reviewed is evidence of significant interrelationships among sleep, race/ethnicity, and psychosocial factors known to confer risk or resilience to CVD, including depression, psychological stress, and close interpersonal relationships. It is proposed that a transdisciplinary research framework that integrates knowledge, methods, and measures from the fields of psychology and sleep research may be used to catalyze advances in the prevention and treatment of CVD. Also discussed are promising new directions, expected challenges, and the importance of training in transdisciplinary science and research approaches. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Insomnia symptoms and risk of cardiovascular diseases among 0.5 million adults: A 10-year cohort

OBJECTIVE

To examine the associations of individual insomnia symptoms with risks of incident cardio-cerebral vascular diseases (CVD) and possible moderating factors among Chinese adults.

METHODS

The China Kadoorie Biobank is a prospective cohort study that recruited participants from 10 areas across China. Data from 487,200 adults 30 to 79 years of age who were free of stroke, coronary heart disease, and cancer at baseline were analyzed. Three insomnia symptoms were assessed with self-reported difficulties in initiating or maintaining sleep, early morning awakening, and daytime dysfunction for at least 3 d/wk at baseline. Incidences of CVD were followed up through disease registries and national health insurance databases until 2016.

RESULTS

During a median of 9.6 years of follow-up, 130,032 cases of CVD were documented. Cox regressions showed that 3 insomnia symptoms were associated with increased risk of total CVD, with respective adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of 1.09 (95% CI 1.07-1.11), 1.07 (95% CI 1.05-1.09), and 1.13 (95% CI 1.09-1.18). Participants with individual symptoms also had higher risks of ischemic heart disease (IHD; HR 1.13, 1.09, and 1.17) and ischemic stroke but not hemorrhagic stroke. Participants with all 3 symptoms were at an 18%, 22%, or 10% higher risk of CVD, IHD, or ischemic stroke compared to nonsymptomatic adults. Associations between 3 symptoms and CVD incidence were consistently stronger in younger adults or those without baseline hypertension (p for interaction <0.05).

CONCLUSIONS

Individual and coexisting insomnia symptoms are independent risk factors for CVD incidence, especially among young adults or adults who have not developed hypertension.

Non-Apnea Sleep Disorder Increases the Risk of Subsequent Female Infertility-A Nationwide Population-Based Cohort Study

Study Objectives

Non-apnea sleep disorder (NASD) increases the risk of hypertension, type 2 diabetes mellitus, chronic kidney disease, cardiovascular disease, and stroke. However, the risk and the time interval of NASD to female infertility has not been thoroughly understood. Our study aimed to determine whether NASD increases the subsequent risk of female infertility.

Methods

This study utilized outpatient and inpatient data from the Longitudinal Health Insurance Database between 2000 and 2010 in Taiwan. We enrolled 50,154 females aged 20 to 45 years old and diagnosed with NASD as outpatients ≥2 times or hospitalized, 16,718 of them who matched our criteria were assigned to the study group. For each NASD patient, two comparison patients were frequency matched by age (each 5-year span), index date, and comorbidities as the control cohort with a total of 33,436 patients. We conducted Cox proportional hazard regression analysis to estimate the effects of NASD on female infertility.

Results

The NASD cohort had an adjusted hazard ratio (HR) of subsequent female infertility of 3.718-fold higher than that of the cohort without sleep disorders. In the stratified age group, NASD had the highest impact on 26-30 years old, with an adjusted HR of 5.146 followed by 31-35 years old (adjusted HR = 3.356). The Kaplan-Meier analysis also showed that in the sixth year of follow-up, the incidence of female infertility was higher in the NASD cohort than in the general population cohort till the end of the follow-up.

Conclusions

Our study demonstrates that NASD patients are at a higher risk of developing female infertility.

Effects of Ramelteon and Other Sleep-Promoting Drugs on Serum Low-Density Lipoprotein and Non-high-density Lipoprotein Cholesterol: A Retrospective Comparative Pilot Study

Melatonin has been suggested to play important roles in lipid metabolism as well as circadian rhythm; however, very few studies explored the effects of ramelteon, a selective melatonin receptor agonist, on serum lipid profiles. In this study effects of ramelteon on serum lipid profiles were explored, comparing to those of other sleep-promoting drugs including benzodiazepines and non-benzodiazepines, in patients with insomnia. We retrospectively reviewed medical charts of outpatients who were treated with ramelteon (8 mg/d) or other sleep-promoting drugs for no less than 8 weeks during the period between October 1st, 2011 and September 30th, 2014, and compared the changes in serum lipid profiles between the two groups. Patients with regular dialysis or malignant diseases treated with cytotoxic anti-cancer drugs, or whose lipid-lowering drugs were altered during the study period, were excluded. Among 365 or 855 outpatients treated with ramelteon or other sleep-promoting drugs, 35 or 46 patients, respectively, had complete serum low-density lipoprotein cholesterol (LDL-C) or non-high-density lipoprotein cholesterol (non-HDL-C) data. Serum LDL-C was significantly reduced from 103.1±4.4 to 94.6±4.2 mg/dL (8.2% reduction, p<0.05, n=31) in the ramelteon group, and was not significantly changed (p=0.23, n=40) in the other sleep-promoting drug group. Non-HDL-C was significantly decreased from 138.8±6.0 to 130.6±4.9 mg/dL (5.9% reduction, p<0.05, n=32) in the ramelteon group, and was not significantly altered (p=0.29, n=42) in the other sleep-promoting drug group. Ramelteon, but not other sleep-promoting drugs, specifically lowers serum LDL-C and non-HDL-C levels.

Sleep, Autonomic Nervous Function and Atherosclerosis

Behavioral and psychosocial factors related to development of cardiovascular disease have been gaining increased attention. Notably, sleep is considered to be one of the most important behavioral factors involved in progression of atherosclerosis and cardiovascular events, with autonomic nervous function a potential mechanism. Several studies have shown associations of sleep and autonomic dysfunction with major surrogate markers of atherosclerosis, such as carotid intima-media thickness and arterial stiffness. Endocrinological, immunological, oxidative, inflammatory, and metabolic responses, as well as endothelial dysfunction may mediate the effects of the autonomic nervous system. For this review, we examined recent findings related to sleep, autonomic nervous dysfunction, and atherosclerosis, with the aim of understanding the involved pathophysiological mechanisms.

Sleep quality correlates with the carotid intima-media thickness in stroke-free community-dwelling adults living in rural Ecuador. The Atahualpa Project

BACKGROUND/OBJECTIVES

Evidence of an association between sleep disorders and extracranial atherosclerosis is limited and has not been studied in remote rural settings, where living conditions and cardiovascular risk factors are different than in urban centers. We assessed the relationship between the carotid intima-media thickness (cIMT) and sleep quality in stroke-free individuals aged ≥40 years living in rural Ecuador.

METHODS

Applying a population-based study design, participants underwent face-to-face interviews using the Pittsburgh Sleep Quality Index (PSQI) to assess sleep quality, and sonographic examinations for measurement of the carotid intima-media thickness (cIMT). The association between the cIMT and sleep quality (as the dependent variable) was assessed by means of generalized linear models, adjusted for relevant confounders.

RESULTS

The mean age of 561 participants was 60.4 ± 12.6 years (58% women). The mean PSQI was 4.6 ± 2.2 points. Of those, 79 (14%) individuals had an increased cIMT (>1 mm). A model adjusted for demographics showed a significant association between increased cIMT and the PSQI score (β: 0.602; 95% C.I.: 0.027-1.177; p = 0.040). This relationship was reduced when cardiovascular risk factors were added to the model (β: 0.514; 95% C.I.: -0.072 - 1.101; p = 0.086). When the model was adjusted for demographics and psychological distress, the association between increased cIMT and the PSQI score became significant (β: 0.573; 95% C.I.: 0.013-1.133; p = 0.045). In addition, both symptoms of depression (p = 0.032) and anxiety (p < 0.001) remained independently significant.

CONCLUSIONS

This study shows an association between increased cIMT and the PSQI score, which is, at least, partly mediated by manifestations of psychological distress.

Insomnia in Elderly Patients: Recommendations for Pharmacological Management

Chronic insomnia affects 57% of the elderly in the United States, with impairment of quality of life, function, and health. Chronic insomnia burdens society with billions of dollars in direct and indirect costs of care. The main modalities in the treatment of insomnia in the elderly are psychological/behavioral therapies, pharmacological treatment, or a combination of both. Various specialty societies view psychological/behavioral therapies as the initial treatment intervention. Pharmacotherapy plays an adjunctive role when insomnia symptoms persist or when patients are unable to pursue cognitive behavioral therapies. Current drugs for insomnia fall into different classes: orexin agonists, histamine receptor antagonists, non-benzodiazepine gamma aminobutyric acid receptor agonists, and benzodiazepines. This review focuses on Food and Drug Administration (FDA)-approved drugs for insomnia, including suvorexant, low-dose doxepin, Z-drugs (eszopiclone, zolpidem, zaleplon), benzodiazepines (triazolam, temazepam), and ramelteon. We review the indications, dosing, efficacy, benefits, and harms of these drugs in the elderly, and discuss data on drugs that are commonly used off-label to treat insomnia, and those that are in clinical development. The choice of a hypnotic agent in the elderly is symptom-based. Ramelteon or short-acting Z-drugs can treat sleep-onset insomnia. Suvorexant or low-dose doxepin can improve sleep maintenance. Eszopiclone or zolpidem extended release can be utilized for both sleep onset and sleep maintenance. Low-dose zolpidem sublingual tablets or zaleplon can alleviate middle-of-the-night awakenings. Benzodiazepines should not be used routinely. Trazodone, a commonly used off-label drug for insomnia, improves sleep quality and sleep continuity but carries significant risks. Tiagabine, sometimes used off-label for insomnia, is not effective and should not be utilized. Non-FDA-approved hypnotic agents that are commonly used include melatonin, diphenhydramine, tryptophan, and valerian, despite limited data on benefits and harms. Melatonin slightly improves sleep onset and sleep duration, but product quality and efficacy may vary. Tryptophan decreases sleep onset in adults, but data in the elderly are not available. Valerian is relatively safe but has equivocal benefits on sleep quality. Phase II studies of dual orexin receptor antagonists (almorexant, lemborexant, and filorexant) have shown some improvement in sleep maintenance and sleep continuity. Piromelatine may improve sleep maintenance. Histamine receptor inverse agonists (APD-125, eplivanserin, and LY2624803) improve slow-wave sleep but, for various reasons, the drug companies withdrew their products.

Insomnia and hypertension: A systematic review

Insomnia is a prevalent sleep disorder that is associated with a multitude of health consequences. Particularly, insomnia has been associated with cardiovascular disease and its precursors, such as hypertension and blood pressure (BP) non-dipping. The present systematic review aimed to summarize the evidence on the concurrent and prospective associations between insomnia and hypertension and/or BP. Using electronic search engines (PubMed, SCOPUS, PsycINFO), 5,618 articles published from January 1970 to December 2017 were identified, and 64 met the inclusion criteria (26 to 162,121 participants; age range: 18-100; 46.4% male). Insomnia was based on diagnostic or non-diagnostic criteria. Hypertension was based on self-or physician-reports, antihypertensive medication use, and/or measured BP. Findings indicate that when insomnia is frequent, chronic, and/or accompanied with short sleep duration or objective markers of arousal, there is a strong association with hypertension/BP. Based on limited studies, hypertension did not significantly predict future insomnia in middle-aged adults, but did in older adults. Based on a majority of case-control studies, no differences in BP were found between participants with and without insomnia. Further research is needed to identify putative pathophysiological mechanisms underlying the link between insomnia and hypertension. The impact of insomnia therapy on BP should also be further examined in the future.

Exercise can improve sleep quality: a systematic review and meta-analysis

Background

Insomnia is common. However, no systematic reviews have examined the effect of exercise on patients with primary and secondary insomnia, defined as both sleep disruption and daytime impairment. This systematic review and meta-analysis aimed to examine the effectiveness/efficacy of exercise in patients with insomnia.

Methods

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, PsycINFO, World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov to identify all randomized controlled trials that examined the effects of exercise on various sleep parameters in patients with insomnia. All participants were diagnosed with insomnia, using standard diagnostic criteria or predetermined criteria and standard measures. Data on outcome measures were subjected to meta-analyses using random-effects models. The Cochrane Risk of Bias Tool and Grading of Recommendations, Assessment, Development, and Evaluation approach were used to assess the quality of the individual studies and the body of evidence, respectively.

Results

We included nine studies with a total of 557 participants. According to the Pittsburgh Sleep Quality Index (mean difference [MD], 2.87 points lower in the intervention group; 95% confidence interval [CI], 3.95 points lower to 1.79 points lower; low-quality evidence) and the Insomnia Severity Index (MD, 3.22 points lower in the intervention group; 95% CI, 5.36 points lower to 1.07 points lower; very low-quality evidence), exercise was beneficial. However, exercise interventions were not associated with improved sleep efficiency (MD, 0.56% lower in the intervention group; 95% CI, 3.42% lower to 2.31% higher; moderate-quality evidence). Only four studies noted adverse effects. Most studies had a high or unclear risk of selection bias.

Discussion

Our findings suggest that exercise can improve sleep quality without notable adverse effects. Most trials had a high risk of selection bias. Higher quality research is needed.

Sleep Characteristics and Carotid Atherosclerosis Among Midlife Women

Introduction

Midlife, which encompasses the menopause transition in women, can be a time of disrupted sleep and accelerated atherosclerosis accumulation. Short or poor sleep quality has been associated with cardiovascular disease (CVD) risk; few studies have investigated relations among midlife women. We tested whether shorter actigraphy sleep time or poorer subjective sleep quality was associated with carotid atherosclerosis among midlife women.

Aims and Methods

Two hundred fifty-six peri- and postmenopausal women aged 40-60 years completed 3 days of wrist actigraphy, hot flash monitoring, questionnaires (Pittsburgh Sleep Quality Index [PSQI], Berlin), a blood draw, and carotid ultrasound [intima media thickness (IMT), plaque]. Associations of objective (actigraphy) and subjective (PSQI) sleep with IMT/plaque were tested in regression models (covariates: age, race, education, body mass index, blood pressure, lipids, insulin resistance, medications, snoring, depressive symptoms, sleep hot flashes, and estradiol).

Results

Shorter objective sleep time was associated with higher odds of carotid plaque (for each hour shorter sleep, plaque score ≥ 2, odds ratio (OR) [95% confidence interval, CI] = 1.58 [1.11-2.27], p = .01; plaque score = 1, OR [95% CI] = 0.95 [0.68-1.32], p = .75, vs. no plaque, multivariable). Poorer subjective sleep quality was associated with higher mean IMT [β, b (standard error, SE) = 0.004 (0.002), p = .03], maximal IMT [b (SE) = 0.009 (0.003), p = .005], and plaque [plaque score ≥ 2, OR (95% CI) = 1.23 (1.09-1.40), p = .001; score = 1, OR (95% CI) = 1.06 (0.93-1.21), p = .37, vs. no plaque] in multivariable models. Findings persisted additionally adjusting for sleep hot flashes and estradiol.

Conclusions

Shorter actigraphy-assessed sleep time and poorer subjective sleep quality were associated with increased carotid atherosclerosis among midlife women. Associations persisted adjusting for CVD risk factors, hot flashes, and estradiol.

Sex Differences in the Risk of Developing Acute Coronary Syndrome in Patients With Sleep Disorders: A Population-Based Cohort Study

Studies that focus on the relationship between sex and the risk of acute coronary syndrome (ACS) are scant. The current study investigated the effects of sex differences in the risk of developing ACS in patients with sleep disorders (SDs). This longitudinal population-based cohort study evaluated the incidence and risk of ACS development in 40,232 men and 65,519 women newly diagnosed with SDs between 2002 and 2008 from the Longitudinal Health Insurance Database. The follow-up period began from the entry date and ended on the date of an ACS event or December 31, 2010. Univariable and multivariable Cox proportional hazard regression models were conducted to estimate the sex differences in the risk of ACS. Men with SDs exhibited an increased incidence of ACS compared with women with SDs in all age- and comorbidity-specific subgroups. After covariates were adjusted, the men with SDs exhibited a 1.48-fold adjusted hazard ratio (aHR) of ACS compared with the women with SDs (95% confidence interval [CI] = 1.36-1.60). After age group stratification, the men with SDs in the young adult group exhibited the highest risk of subsequent ACS development compared with the women with SDs (aHR = 2.07, 95% CI = 1.69-2.55), followed by those in middle-aged adults (aHR = 1.52, 95% CI = 1.32-1.76) and older adults groups (aHR = 1.24, 95% CI = 1.11-1.39). This study determined that men with SDs, particularly young men, are at a higher risk of subsequent ACS development compared with women with SDs.

Self-reported sleep duration and napping, cardiac risk factors and markers of subclinical vascular disease: cross-sectional study in older men

STUDYOBJECTIVES

Daytime sleep has been associated with increased risk of cardiovascular disease and heart failure (HF), but the mechanisms remain unclear. We have investigated the association between daytime and night-time sleep patterns and cardiovascular risk markers in older adults including cardiac markers and subclinical markers of atherosclerosis (arterial stiffness and carotid intima-media thickness (CIMT)).

METHODS

Cross-sectional study of 1722 surviving men aged 71-92 examined in 2010-2012 across 24 British towns from a prospective study initiated in 1978-1980. Participants completed a questionnaire and were invited for a physical examination. Men with a history of heart attack or HF (n=251) were excluded from the analysis.

RESULTS

Self-reported daytime sleep duration was associated with higher fasting glucose and insulin levels (p=0.02 and p=0.01, respectively) even after adjustment for age, body mass index, physical activity and social class. Compared with those with no daytime sleep, men with daytime sleep >1 hour, defined as excessive daytime sleepiness (EDS), had a higher risk of raised N-terminal pro-brain natriuretic peptide of ≥400 pg/mL, the diagnostic threshold for HF (OR (95% CI)=1.88 (1.15 to 3.1)), higher mean troponin, reduced lung function (forced expiratory volume in 1 s) and elevated von Willebrand factor, a marker of endothelial dysfunction. However, EDS was unrelated to CIMT and arterial stiffness. By contrast, night-time sleep was only associated with HbA1c (short or long sleep) and arterial stiffness (short sleep).

CONCLUSIONS

Daytime sleep duration of >1 hour may be an early indicator of HF.

Circadian Influence on Metabolism and Inflammation in Atherosclerosis

Many aspects of human health and disease display daily rhythmicity. The brain's suprachiasmic nucleus, which interprets recurring external stimuli, and autonomous molecular networks in peripheral cells together, set our biological circadian clock. Disrupted or misaligned circadian rhythms promote multiple pathologies including chronic inflammatory and metabolic diseases such as atherosclerosis. Here, we discuss studies suggesting that circadian fluctuations in the vessel wall and in the circulation contribute to atherogenesis. Data from humans and mice indicate that an impaired molecular clock, disturbed sleep, and shifting light-dark patterns influence leukocyte and lipid supply in the circulation and alter cellular behavior in atherosclerotic lesions. We propose that a better understanding of both local and systemic circadian rhythms in atherosclerosis will enhance clinical management, treatment, and public health policy.

Insomnia and Risk of Cardiovascular Disease

Insomnia is the most prevalent sleep disorder in the United States and has high comorbidity with a number of cardiovascular diseases (CVDs). In the past decade, a number of observational studies have demonstrated an association between insomnia and incident cardiovascular disease (CVD) morbidity and mortality, including hypertension (HTN), coronary heart disease (CHD), and heart failure (HF). Despite some inconsistencies in the literature, likely due to variations in how insomnia is defined and measured, the existing data suggest that insomnia, especially when accompanied by short sleep duration, is associated with increased risk for HTN, CHD and recurrent acute coronary syndrome, and HF. Purported mechanisms likely relate to dysregulation of the hypothalamic-pituitary axis, increased sympathetic nervous system activity, and increased inflammation. This paper reviews the most recent studies of insomnia and CVD and the potential pathophysiological mechanisms underlying this relationship and highlights the need for randomized trials to further elucidate the nature of the relationship between insomnia and CVD.

Influence of sleep duration on cortical oxygenation in elderly individuals

AIM

Short sleep duration is a risk factor for cardiovascular diseases. Cerebral blood flow and its regulation are affected by pathological conditions commonly observed in the elderly population, such as dementia, atherosclerosis, diabetes mellitus (DM), stroke, and hypertension. The purpose of this study was to examine the influence of sleep duration on cortical oxygenated hemoglobin (OxyHb) using near-infrared spectroscopy (NIRS).

METHODS

Seventy-three individuals (age, 70.1 ± 3.9 years, 51 men and 22 women) participated in this study. Cortical OxyHb levels were measured with NIRS. We evaluated age, body mass index (BMI), smoking status, alcohol intake, sleep duration, hypertension, DM, and hyperlipidemia using a questionnaire. Blood pressure was measured using plethysmography.

RESULTS

Peak OxyHb and area under the NIRS curve significantly decreased in participants with sleep duration <7 h compared with those with sleep duration ≥7 h (0.136 ± 0.212 mM·mm vs 0.378 ± 0.342 mM·mm, P = 0.001; 112.0 ± 243.6 vs 331.7 ± 428.7, P  = 0.012, respectively). Sleep duration was significantly correlated with peak OxyHb level and area under the NIRS curve (r = 0.378, P  = 0.001; r = 0.285, P  = 0.015, respectively). Multiple regression analysis, including age, BMI, sex, smoking status, alcohol intake, sleep duration, hypertension, DM, and hyperlipidemia revealed that sleep duration was the only significant independent factor associated with peak OxyHb and area under the NIRS curve (β = 0.343, P  = 0.004; β = 0.244, P  = 0.049, respectively), and smoking status was independently correlated with time to the peak OxyHb (β = -0.319, P  = 0.009).

CONCLUSION

Sleep duration may be an important factor that influences cortical oxygenation in the elderly population.

Association of Subjective and Objective Sleep Duration as well as Sleep Quality with Non-Invasive Markers of Sub-Clinical Cardiovascular Disease (CVD): A Systematic Review

Aim: Abnormal daily sleep duration and quality have been linked to hypertension, diabetes, stroke, and overall cardiovascular disease (CVD) morbidity & mortality. However, the relationship between daily sleep duration and quality with subclinical measures of CVD remain less well studied. This systematic review evaluated how daily sleep duration and quality affect burden of subclinical CVD in subjects free of symptomatic CVD.

Methods: Literature search was done via MEDLINE, EMBASE, Web of Science until June 2016 and 32 studies met the inclusion criteria. Sleep duration and quality were measured either via subjective methods, as self-reported questionnaires or Pittsburg Sleep Quality Index (PSQI) or via objective methods, as actigraphy or polysomnography or by both. Among subclinical CVD measures, coronary artery calcium (CAC) was measured by electron beam computed tomography, Carotid intima-media thickness (CIMT) measured by high-resolution B-mode ultrasound on carotid arteries, endothelial/microvascular function measured by flow mediated dilation (FMD) or peripheral arterial tone (PAT) or iontophoresis or nailfold capillaroscopy, and arterial stiffness measured by pulse wave velocity (PWV) or ankle brachial index (ABI).

Results: Subjective short sleep duration was associated with CAC and CIMT, but variably associated with endothelial dysfunction (ED) and arterial stiffness; however, subjective long sleep duration was associated with CAC, CIMT and arterial stiffness, but variably associated with ED. Objective short sleep duration was positively associated with CIMT and variably with CAC but not associated with ED. Objective long sleep duration was variably associated with CAC and CIMT but not associated with ED. Poor subjective sleep quality was significantly associated with ED and arterial stiffness but variably associated with CAC and CIMT. Poor objective sleep quality was significantly associated with CIMT, and ED but variably associated with CAC.

Conclusions: Overall, our review provided mixed results, which is generally in line with published literature, with most of the studies showing a significant relationship with subclinical CVD, but only some studies failed to demonstrate such an association. Although such mechanistic relationship needs further evaluation in order to determine appropriate screening strategies in vulnerable populations, this review strongly suggested the existence of a relationship between abnormal sleep duration and quality with increased subclinical CVD burden.

Changes in Plasma Lipids during Exposure to Total Sleep Deprivation

STUDY OBJECTIVES

The effects of sleep loss on plasma lipids, which play an important role in energy homeostasis and signaling, have not been systematically examined. Our aim was to identify lipid species in plasma that increase or decrease reliably during exposure to total sleep deprivation.

DESIGN

Twenty individuals underwent sleep deprivation in a laboratory setting. Blood was drawn every 4 h and mass spectrometry techniques were used to analyze concentrations of 263 lipid species in plasma, including glycerolipids, glycerophospholipids, sphingolipids, and sterols.

SETTING

Chronobiology and Sleep Laboratory, Duke-NUS Graduate Medical School.

PARTICIPANTS

Healthy ethnic-Chinese males aged 21-28 y (n = 20).

INTERVENTIONS

Subjects were kept awake for 40 consecutive hours.

MEASUREMENTS AND RESULTS

Each metabolite time series was modeled as a sum of sinusoidal (circadian) and linear components, and we assessed whether the slope of the linear component differed from zero. More than a third of all individually analyzed lipid profiles exhibited a circadian rhythm and/or a linear change in concentration during sleep deprivation. Twenty-five lipid species showed a linear and predominantly unidirectional trend in concentration levels that was consistent across participants. Choline plasmalogen levels decreased, whereas several phosphatidylcholine (PC) species and triacylglycerides (TAG) carrying polyunsaturated fatty acids increased.

CONCLUSIONS

The decrease in choline plasmalogen levels during sleep deprivation is consistent with prior work demonstrating that these lipids are susceptible to degradation by oxidative stress. The increase in phosphatidylcholines and triacylglycerides suggests that sleep loss might modulate lipid metabolism, which has potential implications for metabolic health in individuals who do not achieve adequate sleep.

Knee Pain and Low Back Pain Additively Disturb Sleep in the General Population: A Cross-Sectional Analysis of the Nagahama Study

Introduction

Association of knee and low back pain with sleep disturbance is poorly understood. We aimed to clarify the independent and combined effects of these orthopedic symptoms on sleep in a large-scale general population.

Methods

Cross-sectional data about sleep and knee/low back pain were collected for 9,611 community residents (53±14 years old) by a structured questionnaire. Sleep duration less than 6 h/d was defined as short sleep. Sleep quality and the presence of knee and low back pain were evaluated by dichotomous questions. Subjects who complained about knee or low back pains were graded by tertiles of a numerical response scale (NRS) score and a Roland-Morris disability questionnaire (RDQ) score respectively. Multivariate regression analyses were performed to determine the correlates of short sleep duration and poor sleep quality.

Results

Frequency of participants who complained of the orthopedic symptoms was as follows; knee pain, 29.0%; low back pain, 42.0% and both knee and low back pain 17.6%. Both knee and low back pain were significantly and independently associated with short sleep duration (knee pain: odds ratio (OR) = 1.19, p<0.01; low back pain: OR = 1.13, p = 0.01) and poor sleep quality (knee pain: OR = 1.22, p<0.01; low back pain; OR = 1.57, p<0.01). The group in the highest tertile of the NRS or RDQ score had the highest risk for short sleep duration and poor sleep quality except for the relationship between the highest tertile of the RDQ score and short sleep duration.(the highest tertile of the NRS: OR for short sleep duration = 1.31, p<0.01; OR for poor sleep quality = 1.47, p<0.01; the highest tertile of the RDQ: OR for short sleep duration = 1.11, p = 0.12; OR for poor sleep quality = 1.81, p<0.01) Further, coincident knee and low back pain raised the odds ratios for short sleep duration (either of knee or low back pain: OR = 1.10, p = 0.06; both knee and low back pain: OR = 1.40, p<0.01) and poor sleep quality (either of knee or low back pain: OR = 1.61, p<0.01; both knee and low back pain: OR = 2.17, p<0.01).

Conclusion

Knee and low back pains were independently associated with short sleep duration and poor sleep quality. Further, they additively increased the correlation with these sleep problems in the general population.

Increased risk of erectile dysfunction among patients with sleep disorders: a nationwide population-based cohort study

AIMS

Few studies have investigated the relationship between sleep disorders (SD) and erectile dysfunction (ED). Therefore, this study explored whether patients with SD in an Asian population are at an increased risk of developing ED.

METHODS

This longitudinal nationwide population-based cohort study investigated the incidence and risk of developing ED in 34,548 men newly diagnosed with SD between 2002 and 2008 from the National Health Insurance Research Database. A total of 138,192 controls without SD were randomly recruited from the general population and frequency matched according to age and sex. The follow-up period began from the date of entering the study cohort until the date of an ED event, censoring, or 31 December 2010. We conducted Cox proportional hazard regression analyses to estimate the effects of SD on the risk of ED.

RESULTS

The SD cohort had a 2.11-fold adjusted hazard ratio (HR) of subsequent ED development compared with the non-SD cohort [95% confidence interval (CI) = 1.89-2.37]. The incidence of ED increased with age for both cohorts and was higher for the patients in the SD cohort. Compared with the participants without SD or comorbidities, the patients without SD with any comorbidity exhibited a 1.79-fold risk of developing ED (95% CI = 1.54-2.09); the highest risk was for those with both SD and any comorbidity (HR = 3.34, 95% CI = 2.82-3.95). Furthermore, SD patients who had a particular number of comorbidities showed the dose-response effect of developing ED.

CONCLUSION

This nationwide cohort study determined that ED risk evidently increased in SD patients compared with the general population.