Gender-specific associations of sleep duration with uncontrolled blood pressure in middle-aged patients

Hormone physiology and sleep dynamics among BaYaka foragers of the Congo Basin: Gendered associations between nighttime activity, testosterone, and cortisol

Sleep quality is an important contributor to health disparities and affects the physiological function of the immune and endocrine systems, shaping how resources are allocated to life history demands. Past work in industrial and post-industrial societies has shown that lower total sleep time (TST) or more disrupted nighttime sleep are linked to flatter diurnal slopes for cortisol and lower testosterone production. There has been little focus on these physiological links in other socio-ecological settings where routine sleep conditions and nighttime activity demands differ. We collected salivary hormone (testosterone, cortisol) and actigraphy-based sleep data from Congolese BaYaka foragers (N = 39), who have relatively short and fragmented nighttime sleep, on average, in part due to their typical social sleep conditions and nighttime activity. The hormone and sleep data collections were separated by an average of 11.23 days (testosterone) and 2.84 days (cortisol). We found gendered links between nighttime activity and adults' hormone profiles. Contrary to past findings in Euro-American contexts, BaYaka men who were more active at night, on average, had higher evening testosterone than those with lower nighttime activity, with a relatively flat slope relating nighttime activity and evening testosterone in women. Women had steeper diurnal cortisol curves with less disrupted sleep. Men had steeper cortisol diurnal curves if they were more active at night. BaYaka men often hunt and socialize when active at night, which may help explain these patterns. Overall, our findings indicate that the nature of nighttime activities, including their possible social and subsistence contexts, are potentially important modifiers of sleep quality-physiology links, meriting further research across contexts.

The stress of losing sleep: Sex-specific neurobiological outcomes

Sleep is a vital and evolutionarily conserved process, critical to daily functioning and homeostatic balance. Losing sleep is inherently stressful and leads to numerous detrimental physiological outcomes. Despite sleep disturbances affecting everyone, women and female rodents are often excluded or underrepresented in clinical and pre-clinical studies. Advancing our understanding of the role of biological sex in the responses to sleep loss stands to greatly improve our ability to understand and treat health consequences of insufficient sleep. As such, this review discusses sex differences in response to sleep deprivation, with a focus on the sympathetic nervous system stress response and activation of the hypothalamic-pituitary-adrenal (HPA) axis. We review sex differences in several stress-related consequences of sleep loss, including inflammation, learning and memory deficits, and mood related changes. Focusing on women's health, we discuss the effects of sleep deprivation during the peripartum period. In closing, we present neurobiological mechanisms, including the contribution of sex hormones, orexins, circadian timing systems, and astrocytic neuromodulation, that may underlie potential sex differences in sleep deprivation responses.

Uncontrolled Blood Pressure in Hypertensive Patients with High Medication Adherence: A Korean Nationwide Population-Based Study

Background

Uncontrolled blood pressure (BP) is relatively common despite treatment with antihypertensive medication. This study aimed to investigate factors associated with uncontrolled systolic BP (SBP) and diastolic BP (DBP) separately in hypertensive patients with high medication adherence in Korea.

Methods

This population-based cross-sectional study included 3,236 participants in the Korea National Health and Nutrition Examination Survey from 2013 to 2015. Hypertensive patients with high medication adherence were defined when they stated that they were taking antihypertensive medication daily. “Uncontrolled SBP and DBP” were defined as SBP ≥140 mm Hg and DBP ≥90 mm Hg, respectively. Data were analyzed using logistic regression to determine the association between uncontrolled SBP or DBP and various factors.

Results

The prevalence of uncontrolled SBP and uncontrolled DBP was 23.3%, and 9.0%, respectively. In multivariate analysis, uncontrolled SBP was positively associated with older age, female sex, blue-collar occupation or no work (vs. white-collar), presence of a spouse, short sleep duration, frequent heavy alcohol drinking, longer hypertension duration, diabetes, stroke, and missing antihypertensive medication on the examination day, but negatively associated with high stress. Uncontrolled DBP was positively associated with frequent heavy alcohol drinking, but negatively associated with older age, blue-collar occupation or no work (vs. white-collar), and diabetes.

Conclusion

After excluding low medication adherence, we identified various factors associated with uncontrolled SBP or DBP in Korean adults with treated hypertension. There were differences between factors associated with uncontrolled SBP or DBP. Separate analysis of SBP and DBP may help understand the factors involved in BP control.

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

OBJECTIVES

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

DESIGN

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

PARTICIPANTS

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

PRIMARY OUTCOME MEASURE

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

RESULTS

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

CONCLUSION

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

Association between sleep duration and electrocardiographic ischemic changes in middle-aged population: Isfahan Healthy Heart Program

BACKGROUND

Recent studies examining the association between sleep duration and cardiovascular disease (CVD) showed inconsistent results. The aim of our study was to evaluate the association between self-reported night sleep duration and ischemic changes in electrocardiography (ECG).

METHODS

We conducted this cross-sectional study on 3513 participants from Iranian middle-aged population as a part of Isfahan Healthy Heart Program (IHHP), Isfahan, Iran. Sleep duration was obtained by questioning participants. The frequency of electrocardiographic ischemic changes was calculated using ECG Minnesota coding system.

RESULTS

Short sleep duration was associated with increased frequency of electrocardiographic ischemic changes. In a fully adjusted multiple logistic regression analysis, the odds ratio (OR) for short sleep duration less than 5 hours per night was 1.501 [95% confidence interval (CI) for OR: 1.085-2.076] compared to 8 hours of sleep. After stratifying the study population into sex groups, the association remained significant only in women. The OR for short sleep less than 5 hours per night was 1.565 (95% CI for OR: 1.052-2.329) and 1.455 (95% CI for OR: 0.833-2.539) in women and men, respectively. There was no association between long sleep duration and electrocardiographic ischemic changes in men and women.

CONCLUSION

We concluded that there is a positive association between short sleep duration and frequency of electrocardiographic ischemic changes in middle-aged women. This association suggests that short sleep duration may increase the risk of ischemic heart disease (IHD) in women, and this need to be evaluated in further studies.

The effects of short sleep duration on proteinuria and chronic kidney disease: a systematic review and meta-analysis

Background

The risks of proteinuria and chronic kidney disease (CKD) in adults who regularly have short sleep duration (short sleepers) are controversial. The aim of this meta-analysis was to assess the effects of short sleep duration on proteinuria and CKD.

Methods

A literature search was conducted using MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews from the inception of the databases through November 2015. Studies that reported relative risks, odd ratios or hazard ratios comparing the risks of proteinuria and CKD in short sleepers were included. Pooled risk ratios (RR) and 95% confidence intervals (CI) were computed utilizing a random-effect, generic inverse variance method.

Results

Six observational studies with 252 075 individuals and three observational studies with 37 197 individuals were included in the analyses to assess the risks of CKD and proteinuria in short sleepers, respectively. The pooled RR of CKD in short sleepers was 1.51 (95% CI, 0.99-2.55). When meta-analysis was restricted only to studies with adjusted analysis for confounders assessing the risk of CKD in short sleepers, the pooled RR of CKD was 1.54 (95% CI, 0.80-2.95). The pooled RR of proteinuria in short sleepers was 1.47 (95% CI, 1.26-1.72).

Conclusions

Despite the lack of significant association between short sleep duration and CKD, our meta-analysis suggests a potential association between short sleep duration and proteinuria, a surrogate marker for kidney disease progression. Future study is required to investigate if reversal of short sleep helps reduce proteinuria.