Associations Between Objective Sleep and Ambulatory Blood Pressure in a Community Sample

Associations of maternal sleep trajectories during pregnancy and adverse perinatal outcomes: a prospective cohort study

OBJECTIVE

Sleep problems are common in pregnant women and sleep is altered during pregnancy. However, the associations between sleep trajectory patterns and adverse maternal and neonatal outcomes are unclear. The current study aims to identify sleep trajectory patterns and explore their associations with adverse perinatal outcomes in a prospective cohort study.

METHODS

Pregnant women (N = 232) completed the Pittsburgh Sleep Quality Index each trimester during pregnancy in Tianjin, China. Perinatal outcomes were extracted from the hospital delivery records. Latent class growth analysis (LCGA) described the trajectories of sleep timing, duration, and efficiency. Multivariable linear regression and multivariable logistic regression were employed to evaluate associations between sleep trajectory patterns and perinatal outcomes.

RESULTS

Trajectories were identified for bedtime (early, 49.1%; delaying, 50.9%), wake-up time (early, 82.8% of the sample; late, 17.2%), duration (short, 5.2%; adequate 78.0%; excessive, 16.8%), and efficiency (high, 88.4%; decreasing, 11.6%). Compared with women in more optimal sleep groups, those in the late wake-up, excessive duration, and decreasing efficiency groups had babies with shorter birth lengths (β range, -0.50 to -0.28, p < 0.05). Moreover, women in the decreasing efficiency group had babies with lower birth weight (β, -0.44; p < 0.05). Women in the delaying bedtime group had greater odds of preterm delivery (OR, 4.57; p < 0.05), while those in the decreasing efficiency group had greater odds of cesarean section (OR, 3.12; p < 0.05).

CONCLUSIONS

Less optimal sleep trajectory patterns during pregnancy are associated with perinatal outcomes. Therefore, early assessment of maternal sleep during pregnancy is significant for identifying at-risk women and initiating interventions to reduce perinatal outcomes.

Sleep Efficiency and Sleep Onset Latency in One Saskatchewan First Nation

BACKGROUND

Sleep efficiency and sleep onset latency are two measures that can be used to assess sleep quality. Factors that are related to sleep quality include age, sex, sociodemographic factors, and physical and mental health status. This study examines factors related to sleep efficiency and sleep onset latency in one First Nation in Saskatchewan, Canada.

METHODS

A baseline survey of the First Nations Sleep Health project was completed between 2018 and 2019 in collaboration with two Cree First Nations. One-night actigraphy evaluations were completed within one of the two First Nations. Objective actigraphy evaluations included sleep efficiency and sleep onset latency. A total of 167 individuals participated, and of these, 156 observations were available for analysis. Statistical analysis was conducted using logistic and linear regression models.

RESULTS

More females (61%) than males participated in the actigraphy study, with the mean age being higher for females (39.6 years) than males (35.0 years). The mean sleep efficiency was 83.38%, and the mean sleep onset latency was 20.74 (SD = 27.25) minutes. Age, chronic pain, ever having high blood pressure, and smoking inside the house were associated with an increased risk of poor sleep efficiency in the multiple logistic regression model. Age, chronic pain, ever having anxiety, heart-related illness, and smoking inside the house were associated with longer sleep onset latency in the multiple linear regression model.

CONCLUSIONS

Sleep efficiency and sleep onset latency were associated with physical and environmental factors in this First Nation.

Recovery Sleep After Sleep Restriction Is Insufficient to Return Elevated Daytime Heart Rate and Systolic Blood Pressure to Baseline Levels

OBJECTIVE

Sleep restriction alters daytime cardiac activity, including elevating heart rate (HR) and blood pressure (BP). There is minimal research on the cumulative effects of sleep loss and the response after subsequent recovery sleep on HR and BP. This study examined patterns of HR and BP across baseline, sleep restriction, and recovery conditions using multiple daytime cardiac measurements.

METHODS

Participants (15 healthy men, mean [standard deviation] = 22.3 [2.8] years) completed an 11-day inpatient protocol with three nights of 10 hours/night baseline sleep opportunity, five sleep restriction nights (5-hour/night sleep opportunity), and two recovery nights (10-hour/night sleep opportunity). Resting HR and BP were measured every 2 hours during wake. Multilevel models with random effects for individuals examined daytime HR and BP across study conditions and days into the study.

RESULTS

Mean daytime HR was 1.2 (0.5) beats/min lower during sleep restriction compared with baseline ( p < .001). During recovery, HR was 5.5 (1.0) beats/min higher ( p < .001), and systolic BP (SBP) was 2.9 (1.1) mm Hg higher ( p = .009). When accounting for days into the study (irrespective of condition) and measurement timing across the day, HR increased by 7.6 beats/min and SBP increased by 3.4 mm Hg across the study period ( p < .001).

CONCLUSIONS

Our findings suggest that daytime HR and SBP increase after successive nights of sleep restriction, even after accounting for measurement time of day. HR and SBP did not recover to baseline levels after two recovery nights of sleep, suggesting that longer recovery sleep may be necessary to recover from multiple, consecutive nights of moderate sleep restriction.

Classification of blood pressure during sleep impacts designation of nocturnal nondipping

The identification of nocturnal nondipping blood pressure (< 10% drop in mean systolic blood pressure from awake to sleep periods), as captured by ambulatory blood pressure monitoring, is a valuable element of risk prediction for cardiovascular disease, independent of daytime or clinic blood pressure measurements. However, capturing measurements, including determination of wake/sleep periods, is challenging. Accordingly, we sought to evaluate the impact of different definitions and algorithms for defining sleep onset on the classification of nocturnal nondipping. Using approaches based upon participant self-reports, applied definition of a common sleep period (12 am -6 am), manual actigraphy, and automated actigraphy we identified changes to the classification of nocturnal nondipping, and conducted a secondary analysis on the potential impact of an ambulatory blood pressure monitor on sleep. Among 61 participants in the Eastern Caribbean Health Outcomes Research Network hypertension study with complete ambulatory blood pressure monitor and sleep data, the concordance for nocturnal nondipping across methods was 0.54 by Fleiss' Kappa (depending on the method, 36 to 51 participants classified as having nocturnal nondipping). Sleep quality for participants with dipping versus nondipping was significantly different for total sleep length when wearing the ambulatory blood pressure monitor (shorter sleep duration) versus not (longer sleep duration), although there were no differences in sleep efficiency or disturbances. These findings indicate that consideration of sleep time measurements is critical for interpreting ambulatory blood pressure. As technology advances to detect blood pressure and sleep patterns, further investigation is needed to determine which method should be used for diagnosis, treatment, and future cardiovascular risk.

Association Between Sleep Efficiency and Hypertension in Chinese Obstructive Sleep Apnea Patients

Objective

We aimed to explore the relationship of sleep efficiency (SE) with the prevalence of hypertension in Chinese obstructive sleep apnea (OSA) patients based on polysomnography (PSG) records.

Methods

We studied 2360 patients with OSA and 764 primary snorers who underwent PSG in our hospital. SE was divided into three grades, including ≥85%, 80%~84.9%, and <80%. Hypertension was defined based either on direct blood pressure measurements, under anti-hypertensive treatments or on physician diagnosis. Multivariate logistic regression models were conducted to investigate the association between SE and hypertension.

Results

After adjusting for potential confounding factors, OSA patients with <80% SE and those with 80% to 84.9% SE were significantly associated with the prevalence of hypertension (OR = 1.248, 95% CI 1.018~1.531, P=0.033; OR = 1.380, 95% CI 1.040~1.832, P=0.026). Compared to primary snorers, OSA combined with <85% SE increased the odds of hypertension. In stratified analysis by SE, risk of hypertension only in those with <80% SE was significantly different between OSA and primary snorers. Furthermore, this relationship between reduced SE and hypertension was evident especially in female, younger ages, obese, moderate and severe OSA patients. No significant relationship between reduced SE and hypertension was found in primary snores group.

Conclusion

We found that poor SE was correlated with the prevalence of hypertension in Chinese OSA patients, but not in those with primary snoring. Moreover, this relationship was evident especially in female, younger ages, obese, moderate and severe OSA patients.

Blood Pressure Cuff Inflation Briefly Increases Female Adolescents' Restlessness During Sleep on the First But Not Second Night of Ambulatory Blood Pressure Monitoring

OBJECTIVE

Ambulatory blood pressure monitoring (ABPM) increases restlessness during adults' sleep in laboratory settings, but there is little evidence of an association among adolescents or in naturalistic environments. This study examined activity levels before and after blood pressure cuff inflation during sleep to determine whether and for how long ABPM increased restlessness during sleep in healthy adolescents.

METHODS

Two hundred thirty-four healthy adolescents (mean age = 15.72 [1.30] years; 54% female; 57% Black) completed two consecutive nights of hourly ABPM and wrist-worn actigraphy. Activity counts during sleep, averaged across 5-minute bins, were compared in the 20 minutes before and after blood pressure cuff inflation using a four-level mixed model (bins within hours within nights within participants). Interactions of bin with night, sex, and race were examined. Covariates included age, sex, and race.

RESULTS

Activity counts in the 5-minute bin immediately after cuff inflation were 10% to 14% higher than all other bins before ( p < .001) and after ( p < .001) cuff inflation. This effect differed by night and sex, as activity levels during 5-minute post-cuff inflation were elevated only on night 1 ( p values < .001) and only in female participants ( p values < .001). Effects did not differ by race.

CONCLUSIONS

Cuff inflation during ABPM briefly increased adolescent female participants' restlessness during sleep. Habituation occurred after one night, so two nights of ABPM may minimize impact on sleep. If only one night of ABPM is feasible, excluding 5 minutes of actigraphy data after each cuff inflation may accommodate the impact of ABPM on restlessness during sleep.

Daily sleep in relation to subjective and physiological stress in an occupational context: Daily vigour as a mediator

Studies on the stress-sleep relationship consistently demonstrate negative effects of stress on sleep. The reversed relation, however, has received less research attention. Also, field studies on physiological stress are scarce. The aim of this day-level diary study was to examine daily relationships between sleep quality and quantity, and subjective and physiological stress in an occupational context. Moreover, we examined daily vigour as an underlying mechanism of the sleep-stress relationship. Participants were 167 knowledge workers who filled in daily questionnaires measuring sleep quality and quantity, morning vigour and subjective afternoon stress on Tuesdays and Thursdays for 5 weeks. Physiological stress was assessed with cortisol decline from morning peak to evening, and with blood pressure in the afternoon. Multilevel path analysis results showed that better sleep quality and longer sleep hours predicted increased vigour the following morning, which in turn predicted lower subjective stress in the afternoon. Sleep quality and quantity were not related to physiological stress neither directly nor indirectly via morning vigour. On the basis of our results, sleep should be considered as a factor affecting vigour which in turn seems to lower stress.

Association Between Nap and Reported Cognitive Function and Role of Sleep Debt: A Population-Based Study

Background and Purpose

The relationship between napping and cognition remains controversial. This study aimed to investigate the association between napping and cognition according to sleep debt in the Korean adult population.

Methods

A population-based nationwide cross-sectional survey was conducted in 2018. A two-stage stratified random sample of Koreans aged ≥19 years was selected and evaluated using questionnaires by trained interviewers. Cognitive function was assessed using the Mail-In Cognitive Function Screening Instrument (MCFSI). Sleep habits on weekdays and weekends, napping, and subjective sleep requirements were assessed using the questionnaires. Accumulated sleep debt was calculated by subtracting the weekly average sleep duration from subjective sleep requirements. Sleep quality, daytime sleepiness, insomnia, depression, demographics, and comorbidities were assessed. Participants were grouped into those with sleep debt ≤60 min and those with sleep debt >60 min. Multiple linear regression was used to estimate the independent association between the factors and cognition.

Results

In total, 2,501 participants were included in the analysis. Naps were reported in 726 (29.0%) participants (nappers). The mean MCFSI score was higher in nappers (3.4±3.6) than in non-nappers (2.3±3.0) (p<0.001). Multiple linear regression controlling for age, alcohol, smoking, depression, insomnia, daytime sleepiness, sleep quality, and education revealed that 30 to 60 min of napping was associated with worse cognitive function in participants with sleep debts ≤60 min, while >60 min of napping was associated with better cognitive function in participants with sleep debts >60 min.

Conclusions

In general, naps are associated with worse cognitive function in the Korean adult population. However, for those with sleep debt of >60 min, naps for >60 min were associated with better cognitive function.

[Interaction between ischemic stroke risk loci identified by genome-wide association studies and sleep habits]

OBJECTIVE

To explore the relationship between sleep habits (sleep duration, sleep efficiency, sleep onset timing) and ischemic stroke, and whether there is an interaction between sleep habits and ischemic stroke susceptibility gene loci.

METHODS

A questionnaire survey, physical examination, blood biochemical testing and genotyping were conducted among rural residents in Beijing, and the gene loci of ischemic stroke suggested by previous genome-wide association studies (GWAS) were screened. Multivariable generalized linear model was used to analyze the correlation between sleep habits, sleep-gene interaction and ischemic stroke.

RESULTS

A total of 4 648 subjects with an average age of (58.5±8.7) years were enrolled, including 1 316 patients with ischemic stroke. Compared with non-stroke patients, stroke patients with sleep duration ≥9 hours, sleep efficiency < 80%, and sleep onset timing earlier than 22:00 accounted for a higher proportion (P < 0.05). There was no significant association between sleep duration and risk of ischemic stroke (OR=1.04, 95%CI: 0.99-1.10, P=0.085). Sleep efficiency was inversely associated with the risk of ischemic stroke (OR=0.18, 95%CI: 0.06-0.53, P=0.002). The risk of ischemic stroke in the subjects with sleep efficiency < 80% was 1.47-fold (95%CI: 1.03-2.10, P=0.033) of that in the subjects with sleep efficiency ≥80%. Falling asleep earlier than 22:00 was associated with 1.26 times greater risk of stroke than falling asleep between 22:00 and 22:59 (95%CI: 1.04-1.52, P=0.017). Multifactorial adjustment model showed that rs579459 on ABO gene had an interaction with sleep time (P for interaction =0.040). When there were two T alleles for rs579459 on the ABO gene, those who fell asleep before 22:00 had 1.56 times (95%CI: 1.20-2.04, P=0.001) the risk of stroke compared with those who fell asleep between 22:00 and 22:59, and there was no significant difference when the number of pathogenic alleles was 0 or 1. In the model adjusted only for gender, age and family structure, sleep duration and the number of T allele rs2634074 on PITX2 gene had an interaction with ischemic stroke (P for interaction=0.033).

CONCLUSION

Decreased sleep efficiency is associated with increased risk of ischemic stroke, and falling asleep earlier than 22:00 is associated with higher risk of ischemic stroke. Sleep onset timing interacted with rs579459 in ABO gene and the risk of ischemic stroke. Sleep duration and PITX2 rs2634074 may have a potential interaction with ischemic stroke risk.

Objectively-measured sleep patterns and cardiometabolic health in a rural South African setting: a cross sectional analysis

Background

To investigate the relationship between objectively-measured, free-living sleep patterns, and cardiometabolic health, in a rural South African health and demographic surveillance site.

Methods

Wrist-mounted actigraphy data was collected over nine days from 167 adults (≥ 40 years). Sleep patterns were constructed from tertiles of sleep quantity and quality parameters (TST: total sleep time, AC: activity counts during sleep) from valid minute-by-minute data. The reference category was Moderate TST/Low-to-Moderate AC. Self-reported data included behavioural, health and socio-demographic variables. Biological data included anthropometry, resting blood pressure and fasting blood glucose, insulin and lipids. Binary and ordinal logistic regression models were constructed to determine the association between TST and AC, the factors associated with sleeping patterns, and the association between sleeping patterns and Insulin resistance (HOMA-IR) and Metabolic Syndrome (MetS). HOMA-IR and MetS were also examined across sleep patterns using analysis of variance models.

Results

A total of 139 adults (71.2% female) had a complete dataset. In unadjusted analyses, females had poorer sleep quality, were more physically active, and displayed poorer cardiometabolc health and greater adiposity than males (p ≤ 0.017). There were no sex differences in TST or sleep pattern distribution (p ≤ 0.901). Not being classified as Low TST/High AC or exposed to ≥ 1 bout of Low TST/High AC sleep was associated with lower physical activity, longer sleep duration, better sleep quality and lower IR (p ≤ 0.0452). In multivariate analyses, there was no association between TST and AC (p = 0.921), while increasing age and people-to-bedroom density, and lower physical activity where significantly associated with increasing TST (p ≤ 0.027). Participants classified as Low TST/High AC had significantly higher HOMA-IR, but not MetS, compared with Moderate TST/Low AC (p = 0.021). Being exposed to ≥ 1 bout of Low TST/High AC sleep was significantly associated with hypertension (OR = 2.31, 95%CI: 1.00, 5.34), but not for HOMA-IR or MetS (p ≥ 0.227).

Conclusions

Long sleep was not associated with increased sleep fragmentation. Short, fragmented sleep was associated with insulin resistance. Exposure to at least one bout of short, fragmented sleep increased the likelihood of hypertension. Further studies are required to identify the factors associated with short, fragmented sleep in this setting.

The association of actigraphy-assessed sleep duration with sleep blood pressure, nocturnal hypertension, and nondipping blood pressure: the coronary artery risk development in young adults (CARDIA) study

OBJECTIVE

Nocturnal hypertension and nondipping systolic blood pressure (SBP) are associated with increased cardiovascular disease (CVD) risk. Short and long sleep duration (SSD and LSD) are also associated with increased CVD risk and may be risk factors for nocturnal hypertension and nondipping SBP. We examined the association between SSD and LSD with sleep BP, nocturnal hypertension, and nondipping SBP among 647 white and African American Coronary Artery Risk Development in Young Adults (CARDIA) study participants who completed 24-h ambulatory BP monitoring, wrist actigraphy, and sleep diaries in 2015-2016.

METHODS

The times when participants were asleep and awake were determined from actigraphy complemented by sleep diaries. Nocturnal hypertension was defined as sleep BP ≥120/70 mmHg and nondipping SBP as mean sleep-to-awake SBP ratio >0.90. Sleep duration was categorized as SSD (<6 h), normal sleep duration (NSD: 6-8.9 h), and LSD (≥9 h).

RESULTS

The prevalence of SSD and LSD were 13.9 and 21.1%, respectively. Compared to participants with NSD, participants with LSD had higher mean sleep SBP (2.1 mmHg, 95% confidence interval [CI] 0.2, 4.1 mmHg) and diastolic BP (1.7 mmHg, 95% CI 0.5, 3.0 mmHg). Participants with LSD had a higher prevalence of nocturnal hypertension (prevalence ratio [PR]: 1.26, 95% CI 1.03-1.54) and nondipping SBP (PR 1.33, 95% CI 1.03-1.72) compared to participants with NSD. There was no evidence of an association between SSD and sleep SBP or DBP, nocturnal hypertension, or nondipping SBP.

CONCLUSIONS

These findings suggest that LSD may be associated with nocturnal hypertension and nondipping SBP.

Workplace Discrimination and Short Sleep Among Healthcare Workers: The Buffering Effect of People-Oriented Culture

OBJECTIVE

Examine the association of discrimination and short sleep and the buffering effect of people-oriented culture in the workplace among nurses and patient care associates.

METHODS

Used a mixed-methods design from the 2018 Boston Hospital Workers Health Study (N = 845) and semi-structured interviews among nurse directors (N = 16).

RESULTS

We found that people-oriented culture reduced the odds of short sleep and slightly attenuated the association of discrimination and short sleep. People-oriented culture did not buffer the effects of discrimination on short sleep. Qualitative findings showed that discrimination occurred between co-workers in relation to their job titles and existing support in the workplace does not address discrimination.

CONCLUSIONS

Healthcare industries need to implement specific programs and services aimed at addressing discrimination which can potentially improve health outcomes among workers.

A scoping review of racial/ethnic disparities in sleep

BACKGROUND

Despite remarkable achievements in ensuring health equity, racial/ethnic disparities in sleep still persist and are emerging as a major area of concern. Accumulating evidence has not yet been well characterized from a broad perspective. We conducted a scoping review of studies on sleep disparities by race/ethnicity to summarize characteristics of existing studies and identify evidence gaps.

METHODS

We searched PubMed, CINAHL, PsycINFO, and Web of Science databases for studies of racial/ethnic disparities in sleep. Studies that met inclusion criteria were retrieved and organized in a data charting form by study design, sleep measuring methods, sleep features, and racial/ethnic comparisons.

RESULTS

One hundred sixteen studies were included in this review. Most studies focused on disparities between Whites and Blacks. Disproportionately fewer studies examined disparities for Hispanic, Asian, and other racial/ethnic groups. Self-reported sleep was most frequently used. Sleep duration, overall sleep quality, and sleep disordered breathing were frequently studied, whereas other features including sleep efficiency, latency, continuity, and architecture were understudied, particularly in racial minority groups in the US. Current study findings on racial/ethnic disparities in most of sleep features is mixed and inconclusive.

CONCLUSIONS

This review identified significant evidence gaps in racial/ethnic disparities research on sleep. Our results suggest a need for more studies examining diverse sleep features using standardized and robust measuring methods for more valid comparisons of sleep health in diverse race/ethnicity groups.

Sleep moderates the association between arterial stiffness and 24-hour blood pressure variability

BACKGROUND

Arterial stiffness and increased blood pressure variability (BPV) are important subclinical cardiovascular diseases (CVDs). Evidence is accumulating that poor sleep is associated with subclinical CVDs. The purpose of our study was to investigate how sleep was related to arterial stiffness and BPV. We also explored whether sleep moderated the association between arterial stiffness and BPV.

METHODS

We conducted a cross-sectional study including 78 healthy adults aged between 35 and 64 years. Variables of interest were: 1) objective seep characteristics, assessed with a wrist actigraphy for two consecutive nights; 2) arterial stiffness, measured by carotid-femoral pulse wave velocity (cfPWV); and 3) BPV, measured using an ambulatory blood pressure monitor over 24 h and estimated by average real variability.

RESULTS

Lower sleep efficiency was an independent predictor of higher cfPWV and higher systolic BPV, while longer wake after sleep onset (WASO) was an independent predictor of higher cfPWV only. In addition, cfPWV showed a positive relationship with systolic BPV, and this relationship was moderated by sleep efficiency and WASO, respectively. The relationship between cfPWV and systolic BPV became stronger among individuals who had a level of sleep efficiency lower than 84% and who had WASO higher than 67 min, respectively.

CONCLUSION

Our study showed that poor sleep not only directly linked with arterial stiffness and BPV but also moderated the relationship between these two subclinical CVDs. These findings suggest that improving sleep quality could be a target intervention to promote cardiovascular health in clinical practice.

Meta-analysis of age and actigraphy assessed sleep characteristics across the lifespan

STUDY OBJECTIVES

Sleep quantity and continuity vary across the lifespan. Actigraphy is a reliable and widely-used behavioral measure of sleep in research and personal health monitoring. This meta-analysis provides a novel examination of whether age (in years) is associated with actigraphy-assessed sleep across the lifespan.

METHODS

A systematic search of PubMed, Embase.com, Cochrane CENTRAL, and PsycINFO using "actigraphy" and "sleep" terms provided 7,079 titles/abstracts; studies of individuals with known psychiatric or medical comorbidities were excluded. Ninety-one articles (N = 23,365) provided data for six meta-analyses examining sleep duration (k = 89), sleep efficiency (k = 58), bedtime (k = 19) and waketime (k = 9) for individuals ages 6-21, and bedtime (k = 7) and waketime (k = 7) for individuals ages 22 and older.

RESULTS

At older ages, sleep duration was shorter (r = -0.12) and sleep efficiency was lower (r = -0.05). Older age was associated with later bedtime (r = 0.37) and wake-up time (r = 0.24) from ages 6-21, whereas older age was associated with earlier bedtime (r = -0.66) and wake-up time (r = -0.59) for ages 22 and above. The strength of these associations was modified by study continent, but not by any other moderator.

CONCLUSIONS

Age was negatively associated with actigraphy-assessed sleep duration and efficiency, but the effects were small in magnitude. On the other hand, large associations were observed between age and sleep timing, despite a smaller literature and the absence of analyzable data for ages 30-60. Changes in sleep timing, rather than changes in sleep duration or continuity, may better characterize the effects of age on human sleep.

Objective Sleep Efficiency Predicts Cardiovascular Disease in a Community Population: The Sleep Heart Health Study

Background There was little evidence about the role of objective sleep efficiency (SE) in the incidence of major cardiovascular disease (CVD) events. The purpose of this study was to investigate the correlation between objective SE and CVD based on polysomnography. Methods and Results A total of 3810 participants from the SHHS (Sleep Heart Health Study) were selected in the current study. CVD was assessed during an almost 11-year follow-up period. The primary composite cardiovascular outcome was major adverse cardiovascular events, defined as CVD mortality, congestive heart failure, myocardial infarction, and stroke. The secondary composite cardiovascular outcome was major adverse cardiovascular event plus revascularization. Objective measured SE, including SE and wake after sleep onset, was based on in-home polysomnography records. Cox regression analysis was used to explore the association between SE and CVD. After multivariate Cox regression analysis, poor SE (<80%) was significantly associated with primary (hazard ratio [HR], 1.338; 95% CI, 1.025-1.745; P=0.032) and secondary composite cardiovascular outcomes (HR, 1.250; 95% CI, 1.027-1.521; P=0.026); it was also found to be a predictor of CVD mortality (HR, 1.887; 95% CI, 1.224-2.909; P=0.004). Moreover, wake after sleep onset of fourth quartile (>78.0 minutes) was closely correlated with primary (HR, 1.436; 95% CI, 1.066-1.934; P=0.017), secondary composite cardiovascular outcomes (HR, 1.374; 95% CI, 1.103-1.712; P=0.005), and CVD mortality (HR, 2.240; 95% CI, 1.377-3.642; P=0.001). Conclusions Poor SE and long wake after sleep onset, objectively measured by polysomnography, were associated with the increased risk of incident CVD.

Associations of Sleep With Sedentary Behavior and Physical Activity Patterns Across Pregnancy Trimesters

INTRODUCTION

Sleep, sedentary behavior, and moderate-to-vigorous physical activity (MVPA) are altered in pregnancy and may affect pregnancy health; however, how these behaviors are associated with each other is unclear.

METHODS

Pregnant women (N = 120) completed the Pittsburgh Sleep Quality Index and wore an activPAL3 micro and ActiGraph GT3X for 7 days in each trimester to assess sleep, sedentary behavior, and MVPA, respectively. Latent trajectories described patterns of sleep duration, efficiency, and quality as well as sedentary behavior and MVPA. Multinomial logistic regression examined associations of sleep patterns with sedentary behavior and MVPA patterns and, in exploratory analyses, with adverse pregnancy outcomes.

RESULTS

Trajectories were identified for sleep duration (consistently short, 20.7% of sample; consistently adequate, 79.3%), efficiency (consistently low, 17.5%; consistently high, 82.5%), and quality (consistently poor, 15.1%; worsening, 23.5%; and consistently good, 61.5%). Compared with those in more optimal sleep groups, women in the short duration, low efficiency, and worsening quality groups had lower odds of being in the moderate and/or high sedentary behavior group (odds ratio range, 0.21-0.31; 95% confidence interval range, 0.09-0.65). Women in the worsening quality group had greater odds of being in the low MVPA group (odds ratio, 2.51; 95% confidence interval, 1.18-5.38). Trends were observed with women in less optimal sleep groups having greater odds of adverse pregnancy outcomes and lower odds of excessive gestational weight gain.

CONCLUSIONS

Less optimal sleep patterns in pregnancy are associated with less sedentary behavior and MVPA; additional research is needed to confirm associations between sleep and pregnancy outcomes.

Effect of Sleep Disturbances on Blood Pressure

This review summarizes recent literature addressing the association of short sleep duration, shift work, and obstructive sleep apnea with hypertension risk, blood pressure (BP) levels, and 24-hour ambulatory BP. Observational studies demonstrate that subjectively assessed short sleep increases hypertension risk, though conflicting results are observed in studies of objectively assessed short sleep. Intervention studies demonstrate that mild and severe sleep restriction are associated with higher BP. Rotating and night shift work are associated with hypertension as shift work may exacerbate the detrimental impact of short sleep on BP. Further, studies demonstrate that shift work may increase nighttime BP and reduce BP control in patients with hypertension. Finally, moderate to severe obstructive sleep apnea is associated with hypertension, particularly resistant hypertension. Obstructive sleep apnea is also associated with abnormal 24-hour ambulatory BP profiles, including higher daytime and nighttime BP, nondipping BP, and a higher morning surge. Continuous positive airway pressure treatment may lower BP and improve BP dipping. In conclusion, efforts should be made to educate patients and health care providers about the importance of identifying and treating sleep disturbances for hypertension prevention and management. Empirically supported sleep health interventions represent a critical next step to advance this research area and establish causality.

Objective short sleep duration and 24-hour blood pressure

Background

Short sleep duration is a contributor to cardiovascular disease (CVD) events and mortality. Short sleep duration is associated with an increased risk of high clinic blood pressure (BP). BP measured outside the clinic using 24-h ambulatory blood pressure monitoring (ABPM) is a better predictor of an individual's CVD risk. We examined the association between objectively-assessed sleep duration and 24-h ambulatory blood pressure (ABP).

Methods

A total of 893 working adults underwent sleep and ABPM. Participants were fitted with an ABPM device, and measures were taken at 28-30 min intervals. Objective sleep duration, and times of wakefulness and sleep during the 24-h ABPM period were derived from wrist-worn actigraphy. Linear regression, adjusted for age, sex, race/ethnicity, body mass index, smoking status, and diabetes were conducted on the relationship between sleep duration and the ABP measures.

Results

Mean age of participants (final n = 729, 59.5% female, 11.9% Hispanic) was 45.2 ± 10.4 y. Mean actigraphy-derived sleep duration was 6.8 ± 1.2 h. Sleep duration <6 h was associated with a 1.73 mmHg higher 24-h systolic BP (p = 0.031) and 2.17 mmHg higher 24-h diastolic BP (p < 0.001). Shorter sleep duration was not associated with mean awake or asleep systolic BP (p = 0.89 and p = 0.92) or mean awake or asleep diastolic BP (p = 0.30 and p = 0.74).

Conclusions

To our knowledge, this is the largest study conducted which assessed sleep duration objectively while measuring 24-h ABP. Shorter sleep duration is associated with higher 24-h BP and potentially cardiovascular risk.

Fragmented Sleep and the Prevalence of Hypertension in Middle-Aged and Older Individuals

OBJECTIVE

We aimed to investigate the association between fragmented sleep and the prevalence of hypertension in middle-aged and older individuals.

METHODS

This study included 5804 participants with an average age of 63.1±11.2 years from the Sleep Heart Health Study. Fragmented sleep parameters including arousal index in total sleep (ArI-Total), rapid eye movement sleep (ArI-REM), non-rapid eye movement sleep (ArI-NREM), fragmented sleep index (SFI), sleep efficiency (SE) and wake after sleep onset (WASO) were monitored using polysomnography. The information on hypertension, defined as systolic blood pressure (SBP) ≥140 mmHg and/or diastolic blood pressure (DBP) ≥90 mmHg or under antihypertensive treatment, was collected at baseline. We conducted multivariable logistic regression to explore the cross-sectional association between fragmented sleep and the prevalence of hypertension.

RESULTS

After adjusting for potential confounders, fragmented sleep parameters (per 5-unit change) including SE (odds ratio [OR] 0.904; 95% confidence interval [CI] 0.877-0.932; P < 0.001), WASO (OR 1.019; 95% CI 1.012-1.027; P < 0.001), ArI-Total (OR, 1.036; 95% CI, 1.005-1.068; P = 0.024), and ArI-NREM (OR 1.032; 95% CI 1.004-1.062; P = 0.027) were significantly associated with the prevalence of hypertension. In addition, ArI-Total, ArI-NREM, and ArI-REM were positively correlated with both systolic blood pressure and diastolic blood pressure.

CONCLUSION

We found a high prevalence of hypertension among middle-aged and older individuals with fragmented sleep. The causal association between fragmented sleep and hypertension warrants further investigation.

Objectively Measured Sleep Characteristics and Incidence of Ischemic Stroke: The Sleep Heart Health Study

OBJECTIVE

Sleep disorders are associated with the prevalence of stroke. However, there is limited evidence regarding the association between objectively measured sleep characteristics and ischemic stroke.

METHODS

Ischemic stroke was assessed during the mean follow-up period of 11 years in the Sleep Heart Health Study. Sleep parameters such as wake after sleep onset (WASO) and sleep efficiency (SE) were objectively measured based on in-home polysomnography records. Multivariable Cox regression analysis was utilized to examine the relationship between objective sleep characteristics and ischemic stroke incidence.

RESULTS

This study involved 4204 participants (1978 males and 2226 females, 63.8±11.1 years). The incidence of ischemic stroke increased in individuals with long WASO, poor SE, and short sleep duration. Multivariable Cox regression analysis showed that WASO within the fourth quartile (hazard ratio [HR] 3.771, 95% confidence interval [CI] 1.805-7.877, P<0.001), third quartile (HR 3.009, 95% CI 1.433-6.317, P=0.004), and second quartile (HR 3.108, 95% CI 1.470-6.568, P=0.003) had a higher incidence of ischemic stroke than WASO within the first quartile. Poor SE (<80.0%) was also found to be a predictor for ischemic stroke (HR 2.220, 95% CI 1.244-3.960, P=0.007). Additionally, a short sleep duration (<6 h) was associated with an increased risk of ischemic stroke (HR 1.725, 95% CI 1.026-2.899, P=0.040).

CONCLUSION

Our results revealed a relationship between WASO, SE, and sleep duration and ischemic stroke. Therefore, these sleep characteristics may be adequate predictors for the incidence of ischemic stroke.

Subjective Poor Sleep Quality is Associated with Higher Blood Pressure and Prevalent Hypertension in General Population Independent of Sleep Disordered Breathing

OBJECTIVE

To explore the relationship of subjective sleep quality with blood pressure (BP) and hypertension by considering the influence of sleep disordered breathing (SDB) and age in the general population.

METHODS

We evaluated sleep quality using the Pittsburgh sleep quality index (PSQI) and SDB using NoSAS score and measured BP in randomly selected adults in China in 2019. Sleep quality is categorized into four groups as very good, fairly good, fairly bad and very bad. SDB is defined as NoSAS score ≥8. Hypertension is defined as systolic BP ≥140 mmHg and/or diastolic BP ≥90 mmHg, and/or use of antihypertensive medicine within previous 2 weeks. Multi-variable linear and logistic regression analyses were used to assess the association of global PSQI score and sleep quality with BP and prevalent hypertension.

RESULTS

In the 33,341 participants (53.4% women, median age: 48 years), prevalence of hypertension significantly increased from very good to very bad sleepers in total (34.3 vs 42.6 vs 50.3 vs 58.5%), SDB (61.2 vs 68.3 vs 73.3 vs 75.5%) and non-SDB participants (26.8 vs 33.1 vs 40.1 vs 50.9%). In multiple linear regression, PSQI global score showed significant positive association with BP levels in total, SDB and non-SDB participants, consistent in sensitivity analysis by excluding participants who were taking antihypertensives, and in participants aged <60 years in age-stratified analysis. In multivariable logistic regression, odds ratio for presence of hypertension significantly increased from very good to very bad sleepers in total (1 vs 1.08 vs 1.22 vs 1.48), SDB (1 vs 1.17 vs 1.35 vs 1.28) and non-SDB participants (1 vs 1.05 vs 1.14 vs 1.53), consistent in participants aged <60 years.

CONCLUSION

Poor subjective sleep quality is significantly associated with higher BP and prevalent hypertension, independent of SDB in the young- and middle-aged general population, indicating potential of improving sleep quality to lower BP and optimize hypertension management at population level.

Self-Rated Health and Age-Related Differences in Ambulatory Blood Pressure: The Mediating Role of Behavioral and Affective Factors

OBJECTIVE

Despite the well-established association between self-rated health (SRH) and health, little is known about the potential psychobiological mechanisms responsible for such links and if these associations differ by age. The main goals of this study were to investigate the links between SRH and ambulatory blood pressure (ABP), if age moderated the risk, and the health behavior/affective mechanisms responsible for such links.

METHODS

A total of 188 men and women (94 married couples; ages, 18-63 years) completed a standard measure of SRH and a 1-day ABP assessment. Multilevel models were run to examine whether SRH was associated with daily ABP and whether these links were moderated by age. The Monte Carlo method was used to construct confidence intervals for mediation analyses.

RESULTS

Results indicated that poor SRH was associated with higher ambulatory systolic blood pressure (SBP; b = 3.14, SE = 0.68, p < .001) and diastolic blood pressure (DBP; b = 1.34, SE = 0.43, p = .002) levels. Age also moderated the links between SRH and ambulatory SBP (b = 0.19, SE = 0.08, p = .011) and DBP (b = 0.14, SE = 0.05, p = .004), with links being stronger in relatively older individuals. However, only daily life negative affect significantly mediated the age by SRH interaction for both ambulatory SBP and DBP.

CONCLUSIONS

These results highlight the potential psychobiological mechanisms linking SRH to longer-term health outcomes. Such work can inform basic theory in the area as well as intervention approaches that target such pathways.

Short Sleep Duration After Hospital Evaluation for Acute Coronary Syndrome Is Associated With Increased Risk of 6-Month Readmission

OBJECTIVE

Hospital readmission after acute coronary syndrome (ACS) is associated with worsened patient outcomes and financial burden. Short sleep duration is a risk factor for cardiovascular events and may therefore represent a behavioral factor that increases risk of adverse posthospitalization outcomes. This study examined whether short sleep duration in the month after hospital evaluation for ACS is associated with 6-month all-cause emergency department (ED) and hospital readmission.

METHODS

The current analyses entail a secondary analysis of a larger prospective observational cohort study. Sleep duration during the month after hospital evaluation for ACS was assessed subjectively and dichotomized as short (<6 hours) or not short (≥6 hours). A Cox proportional hazards model was used to assess the association between short sleep duration during the month after ACS hospital evaluation and 6-month all-cause ED/hospital readmission.

RESULTS

A total of 576 participants with complete data were included in analyses. Approximately 34% of participants reported short sleep duration during the month after ACS evaluation. Short sleep duration was significantly associated with 6-month all-cause ED/hospital readmission (hazard ratio = 2.03; 95% confidence interval = 1.12-3.66) in the model adjusted for age, sex, race/ethnicity, clinical severity, cardiac and renal markers, depression, acute stress, and including a sleep duration by ACS status interaction.

CONCLUSIONS

Short sleep duration after ACS hospital evaluation is prevalent and is associated with increased risk of all-cause readmission within 6 months of discharge. Current findings suggest that short sleep duration is an important modifiable behavioral factor to consider after hospital evaluation for ACS.