Combined Use of Sleep Quality and Duration Is More Closely Associated With Mortality Risk Among Older Adults: A Population-based Kyoto-Kameoka Prospective Cohort Study

Cohort studies about the sleep duration on the risk of death among Chinese older adults are still lacking. The aim of this study was to examine whether extremely long or short sleep duration was associated with mortality in Chinese adults aged 65 years or older. We included participants aged 65 years or older in 2011 at baseline in 23 provinces from the Chinese Longitudinal Healthy Longevity Survey who were followed up in 2014/2018 in China. Sleep duration was categorized as short sleep duration (< 7 hours) and long sleep duration (> 8 hours). We used the Cox proportional hazards model and restricted cubic spline analysis to explore the association between sleep duration and mortality. Among 9578 participants, short sleep duration was associated with an 11% higher risk of death (adjusted hazard ratio [aHR]: 1.11; 95% confidence interval [CI]: 1.02-1.20) and long sleep duration was associated with a 24% higher risk of death (aHR: 1.24; 95% CI: 1.15-1.34), after adjustment for all covariates. There was a U-shaped association between sleep duration and all-cause mortality (nonlinear, P < .0001). Stratified analyses showed that the risk was higher among older people who smoked and with a higher level of education both for short and long sleepers than for those who never smoked and were illiterate (P value for interaction < .05). There was a U-shaped association between sleep duration and all-cause mortality in Chinese older adults, especially in more educated individuals and smokers. Du M, Liu M, Liu J. The association between sleep duration and the risk of mortality in the Chinese older adults: a national cohort study. J Clin Sleep Med. 2021;17(9):1821-1829.

To evaluate the relations between sleep characteristics and cardiovascular risk factors and napping behavior, and to assess whether daytime napping leads to subsequent better or worse sleep. The sample consisted of 224 (African American, Caucasian, and Asian) middle-aged men and women. Sleep measures included nine nights of actigraphy and sleep diaries, sleep questionnaires, and one night of polysomnography to measure sleep disordered breathing. More frequent napping was associated with shorter nighttime sleep duration averaged across the nine nights of actigraphy (especially among African Americans), more daytime sleepiness, more pain and fatigue by diary, and increased body mass index and waist circumference. Shorter nighttime sleep duration was associated with taking a nap during the next day and taking a nap was associated with less efficient sleep the next night. Napping in middle-aged men and women is associated with overall less nighttime sleep in African Americans and lower sleep efficiency as measured by actigraphy, and increased BMI and central adiposity. These findings point to the importance of measuring of napping in understanding associations of sleep with cardiovascular risk.

A large body of evidence has accumulated over the last five decades regarding the consequences of insufficient sleep duration and/or inadequate sleep quality (including sleep breathing disorders such as obstructive and central sleep apnea). It has been shown that insufficient sleep duration, sleep apnea, and insomnia are associated with a variety of adverse health outcomes.1 The negative effects of sleep disturbances may affect many aspects of human health by inducing metabolic, cardiovascular, immunological, and mental alterations. Furthermore, sleep duration has been found to be an independent risk factor for total mortality. A pioneering population-based study including 1 064 004 individuals, published more than 50 years ago, suggested that an increased mortality risk in men was associated with either short (6 hours or less) or long (9 hours or more) sleep duration.2 In particular, individuals who slept less than five hours per night had very high death rates, and this was also the case for who slept ten or more hours per night. A recent meta-analysis of 60 studies representing over 3 million participants showed a possible increase in cardiovascular mortality associated with either longer or shorter duration of sleep than 7 or 8 hours, thus providing an updated evidence in favor of a J-shaped relationship between sleep duration and mortality.3 It is also worth of mention that subjective poor sleep quality, assessed in 17 out of 60 studies, was independently associated with coronary heart disease but not with cardiovascular mortality and non-fatal stroke. A scientific statement released in 2016 by the American Heart Association, based on a comprehensive review of individual studies and their meta-analyses, highlighted the fact that sleep duration, mostly short sleep, and sleep disorders (insomnia symptoms, sleep-disordered breathing, periodic limb movement disorder, restless leg syndrome) are related to adverse cardiometabolic risk factors, such as obesity, metabolic syndrome, hypertension, type 2 diabetes mellitus, as well as to cardiovascular disease.4 The mechanisms underlying the association between sleep disturbances and unfavorable health consequences remain a topic of debate. Poor sleep quality has been shown to increase circulating levels of leptin and ghrelin, which in turn may promote insulin resistance and development of obesity. Increased plasma adrenaline, norepinephrine, and cortisol concentrations as well as low-grade inflammation and endothelial dysfunction have been associated with abnormal sleep patterns. A putative link between sleep disorders with heightened sympathetic nervous activity and/or reduced parasympathetic activity leading to sympathovagal imbalance and, ultimately, to cardiac autonomic dysfunction has been reported in different clinical settings.5, 6 Several epidemiological studies have shown significant associations between chronic insomnia, short sleep duration, poor sleep quality, and the risk of hypertension resulting from chronic sympathetic overactivity and/or arterial baroreflex dysfunction.7 A meta-analysis from 13 studies (6 cross-sectional studies and 7 prospective cohort studies) including a total of 347,759 participants (115,007 with hypertension) showed a U-shaped relationship between sleep duration and hypertension.8 In particular, the excess of hypertension risk associated with a short sleep period (ie, ≤5 hours) was 81% greater compared to the reference sleep time (ie, 7 hours) in cross-sectional studies and 31% greater in prospective cohort studies. Notably, the association between short sleep duration and hypertension was stronger in women than men. A more recent meta-analysis (comprising 54 studies and 1 074 207 subjects) targeted the relationship between six sleep parameters (ie, obstructive sleep apnea, oxygen desaturation index, sleep quality, short or long sleep duration, and snoring) and revealed that poor sleep quality but not sleep duration was a key risk factor for hypertension (OR = 1.38, 95% CI :1.082–1.760).9 In this issue of the Journal Oliveira-Silva and coworkers10 report the results of a cross-sectional study aimed at investigating the association between sleep quality with cardiac autonomic dysfunction, as assessed by the spectral analysis of heart rate (HR) and blood pressure (BP) variability, in a group of forty-seven treated essential hypertensive men. The study sample did not include patients with overt cardiovascular disease, subclinical target organ damage, grade II and III obesity, elderly, patients on treatment with insulin, beta-blockers, and non-dihydropyridine calcium channel antagonists. Sleep quality was investigated by the Pittsburgh Sleep Quality Index (PSQI). PSQI is a questionnaire examining seven sleep items: subjective sleep quality (a subjective feeling of satisfaction in daily sleep), sleep latency (time for transition from full wakefulness to sleep), habitual sleep efficiency (ratio of hours slept to total hours in bed), daytime dysfunction (trouble staying awake during social activities), sleep duration and use of sleep medication, and sleep disturbance (interruption of sleep). The global PSQI score ranges from 0 to 21, higher numbers reflecting worse sleep quality. A total of 24 out of 47 patients included in the study were identified as "poor sleepers" (PQSI score> 5); their demographic and clinical characteristics were not different from those of patients with preserved or good sleep quality.10 Furthermore, no differences were found in the number antihypertensive drugs (2/3 of patients in both groups were on monotherapy) as well as in the various classes of BP-lowering drugs, in particular diuretics. Cardiovascular parameters were assessed with the patients in sitting position by ten minutes recording of HR and beat-to-beat BP using photo-plethysmography. Autonomic modulation was then evaluated by the spectral analysis of HR and BP variability. Patients with poor sleep quality exhibited an impaired cardiac parasympathetic modulation (ie, lower HR high-frequency band) and reduced cardiac baroreflex sensitivity. In addition, correlation analyses showed that PSQI score was directly related to average HR and inversely related to HR high-frequency band, HR total variance, and cardiac baroreflex sensitivity. Some previous studies evaluating the effect of global sleep status on cardiac autonomic function, as assessed by HR variability and catecholamine levels, have been carried out in patients with cardiovascular disease (ie, acute myocardial infarction). In this critical setting, higher levels of adrenaline and norepinephrine, a significant increase in low-frequency power as well as low-frequency/high-frequency power ratio and reduced high-frequency power were found in 147 patients (61% men) with poor sleep quality as compared to their counterparts with good sleep quality (n = 156, 67% men).11 In clinical terms, sympathetic hyperactivity, associated with short-lasting poor sleep quality, resulted in increased prevalence of ventricular tachycardia in the following week after acute myocardial infarction. The findings provided by Oliveira-Silva et al. extend to the uncomplicated hypertension setting the view that poor sleep quality may adversely affect the sympathovagal balance and worsen the risk of cardiovascular complications in poor sleeper hypertensive patients. Some aspects and limits of this interesting study deserve to be commented on. Subjective and objective estimates of sleep (ie, actigraphy) are often discordant among subjects with sleep disorders who generally tend to under-report sleep time and over-report wake time at night. The PSQI is widely used by clinicians and researchers in order to assess several aspects of sleep as it has been validated in general population-based samples as well as in many different clinical settings. It cannot be ignored, however, that several studies have reported rather limited correlations between subjective evaluation of quality and duration of sleep and more-objective measures. For instance, an analysis of 669 participants in the CARDIA (Coronary Artery Risk Development in Young Adults) Sleep Study documented a moderate correlation (r = 0.45) between self-reported and objectively measured sleep duration based on wrist actigraphy, providing evidence of systematic errors and bias of subjective evaluations.12 Similar conclusions were reported in a large study aimed at comparing self-report sleep quality and actigraphy results in a cohort of 2,086 Hispanic Americans.13 Overall, the PSQI can be regarded as a good screening tool, but not a substitute for sleep disorder diagnoses based on a comprehensive clinical interview performed by skilled clinicians with the support of objective measurements; therefore, data obtained by this questionnaire should be considered with caution.14 The high prevalence of patients with poor sleep quality (ie, 51%) in the Oliveira-Sousa study was similar to that reported by Wang et al. in acute myocardial infarction 11 and raises the question of whether this sample reflects the real burden of sleep disturbances in the community. Data from the 2007 to 2008 National Health Nutrition Examination Survey (NHANES) targeting the prevalence of sleep symptoms have shown that long sleep latency, self-reported difficulty in falling asleep, sleep maintenance difficulties, and early morning awakenings were reported by more than 50% of the participants.15 This supports the concept that sleep disturbances involve a very large fraction of the general population and, consequently, conditions such as hypertension, obesity, diabetes could be even more exposed to the risk of poor quality sleep. Finally, differences in sleep between men and women have been reported in the literature in the last decades; unfortunately, the present study did not address the intriguing aspect of gender-based differences in the association between sleep disorders and cardiac autonomic dysfunction. In community-based studies, women have been shown to report shorter sleep duration, more frequently sleep symptoms, and higher rates of insomnia.16 Furthermore, the strength of association between short sleep duration/poor quality sleep and hypertension has been reported to be stronger in women than in men. In conclusion, the study by Oliveira-Souza and coworkers has the merit of raising the question about the relationship between sleep quality and cardiac autonomic function in the hypertension setting, suggesting that poor sleep quality is accompanied by substantial alterations of the sympathovagal modulation. Assessment of sleep quality, a point so far neglected, should be included in clinical practice and research, as it may contribute to a more comprehensive cardiovascular risk stratification of hypertensive patients as well as to the analysis of factors responsible for cardiac damage. It is evident that further larger studies, based on more accurate evaluation of sleep, are needed in order to more deeply explore the role of alterations of sleep quality on cardiovascular outcomes, as in the recent past it has been performed for the sleep apnea syndrome.17, 18 The authors report no conflicts of interest.

Poor sleep quality, often resulting from poor sleep hygiene, is common among medical students. Educational interventions aimed at improving sleep knowledge are beneficial for sleep quality in healthy populations. However, sleep education is often given minimal attention in medical school curriculums. The aim of the study was to explore whether a short educational intervention could improve sleep knowledge, and consequently sleep quality, among medical students. We recruited preclinical- and clinical-stage medical students during the 2017-2018 academic year. Students completed a demographic survey, the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), and the Assessment of Sleep Knowledge in Medical Education (ASKME) questionnaire. Students then attended a lecture on the physiology and importance of sleep. To assess the efficacy of the intervention, questionnaires were repeated 4 months thereafter. A total of 87 students (31 preclinical) with a mean age of 25.86 years (standard deviation [SD], 3.33), 51 of whom were women, participated in the study. At baseline, students had poor sleep quality with a PSQI mean score of 5.9 (SD, 2.37), without significant sleepiness, and a mean ESS score of 8.86 (SD, 4.32). The mean ASKME scores were consistent with poor sleep knowledge at 11.87 (SD, 4.32). After the intervention, the mean ASKME results improved to 14.15 (SD, 4.5; P < .001), whereas sleep quality did not. The effect was similar in preclinical and clinical medical students. Sleep knowledge was inadequate among medical students, who also experienced poor sleep quality. A short educational intervention improved sleep knowledge but was insufficient at improving sleep quality. Further studies are needed to determine which interventions may provide benefit in both sleep knowledge and sleep quality.

Low handgrip strength (HGS) and abdominal obesity (AO) have been reported to be linked to an increased all-cause mortality risk in older adults. However, the combined impact of AO with low HGS and/or HGS asymmetry on mortality risk remains unclear. Therefore, this study aimed to investigate the synergistic effects of AO and abnormal HGS on mortality risk among Chinese older adults. Baseline data of the China Health and Retirement Longitudinal Study in 2011, along with mortality outcomes obtained in 2018 were used for the analysis. Low HGS was identified as HGS <18 kg in women or <28 kg in men, while HGS asymmetry is defined as an HGS of either hand > 10% stronger than the other. AO was characterized by a waist circumference ≥90 cm in men and ≥85 cm in women. Logistic regression analysis was used to evaluate the relationship between AO, abnormal HGS and mortality risk. A total of 5186 subjects aged 60 years or older were enrolled, 50.6% of whom were male. The proportions of participants with only AO, only low HGS, only HGS asymmetry, low HGS with asymmetry, both AO and low HGS, both AO and asymmetric HGS, and AO with both low HGS and asymmetry were 20.0%, 6.1%, 16.6%, 8.3%, 3.2%, 13.4%, and 3.9%, respectively. Over the course of a 7-year follow-up interval, 970 of these individuals died, with 13.4%, 12.4%, 13.6%, 15.5%, 4.1%, 10.1% and 6.9% of deaths in the above groups, respectively. The adjusted logistic regression analysis model confirmed that only low HGS (OR = 1.897, 95%CI: 1.386-2.596, p<0.001), low HGS with asymmetry (OR = 1.680, 95%CI: 1.265-2.231, p<0.001), and AO combined with both low HGS and asymmetry (OR = 2.029, 95%CI: 1.381-2.981, p<0.001) were associated with a higher risk of mortality. Low HGS, with or without asymmetry, is associated with increased mortality risk in older Chinese adults without AO, and the combination of low HGS and HGS asymmetry further elevates mortality risk in those with AO.

The sleep patterns of humans are greatly influenced by age and sex and have various effects on overall health as they change continuously during the lifespan. We investigated age-dependent changes in sleep properties and their relation to sex in middle-aged individuals. We analyzed data from 2,640 participants (mean age of 49.8 ± 6.8 years at baseline, 50.6% women) in the Korean Genome and Epidemiology Study, which assessed sleep habits using the Pittsburgh Sleep Quality Index and other clinical characteristics. We analyzed the sleep habit changes that occurred between baseline and a follow-up point (mean interval: 12.00 ± 0.16 years). Associations of age and sex with 9 sleep characteristics were evaluated. Age was associated with most of the sleep characteristics cross-sectionally and longitudinally (P < .05), except for the time in bed at baseline (P = .455) and change in sleep duration (P = .561). Compared with men, women had higher Pittsburgh Sleep Quality Index scores, shorter time in bed, shorter sleep duration, and longer latency at baseline (P ≤ .001). Longitudinal deterioration in Pittsburgh Sleep Quality Index score, habitual sleep efficiency, duration, and latency was more prominent in women (P < .001). The sex differences in these longitudinal sleep changes were mainly noticeable before age 60 years (P < .05). Worsening of Pittsburgh Sleep Quality Index scores, habitual sleep efficiency, and latency was most evident in perimenopausal women. Men presented with greater advancement of chronotype (P = .006), with the peak sex-related difference occurring when they were in their late 40s (P = .048). Aging is associated with substantial deterioration in sleep quantity and quality as well as chronotype advancement, with the degree and timing of these changes differing by sex.

Inappropriate sleep duration and poor sleep quality are associated with risk of stroke, but their interactive effect on stroke is unknown. We explored the interactive effect of sleep quality and duration on stroke risk. A prospective cohort study was conducted with 41,786 adults. Sleep quality was assessed using the Pittsburgh Sleep Quality Index. Sleep duration was measured by average hours of sleep per night. Cox regression models were used to calculate the association of sleep duration and quality with stroke. The delta method and a non-conditional logistic regression model were used and the relative excess risk due to interaction (RERI), the attributable proportion (AP), and the synergy index (S) were calculated. Compared with sleep duration 6–8 h/day, the risk ratio of stroke was 1.63 (1.23–2.11) times for sleep duration <6 h/day and 1.40 (1.08–1.75) times for >8 h/day. The stroke risk ratio was 2.37 (1.52–3.41) times in subjects with poor sleep quality compared with those with good sleep quality. Women who slept <6 h/day had higher stroke risk than men who slept <6 h/day. Men who slept >8 h/day had higher stroke risk than women who slept >8 h/day. Men with poor sleep quality had higher stroke risk than women with poor sleep quality. Stroke was associated with short/long sleep duration and poor sleep quality in subjects aged >46 years, compared with those aged 18–45 years. Stroke occurred more frequently in subjects with poor sleep quality combined with short sleep duration (odds ratio: 6.75; 95% confidence interval (CI): 2.45–14.12). RERI, AP, and S values (and their 95% CIs) were 5.54 (3.75–8.12), 0.72 (0.56–0.80), and 5.69 (4.23–9.90) for the poor sleep quality interact with short sleep duration. In persons with poor sleep quality accompanied by long sleep duration, RERI, AP, and S (95% CI) were 1.12 (1.01–1.27), 0.35 (0.26–0.51), and 2.05 (1.57–2.96), respectively. Subjective sleep disturbances are related with risk of stroke in Chinese adults. There are additive interactions between short/long sleep duration and poor sleep quality that affect risk of stroke.

Sleep duration and quality in relation to non-alcoholic fatty liver disease in middle-aged workers and their spouses

BackgroundSleep is an essential component of human health and well-being, playing a crucial role in several cognitive processes, including attention, memory, and executive function. In this study, we aimed to examine the association between sleep quality, sleep duration and cognitive functioning among older men and women in India.MethodsData come from the World Health Organization’s Study on global AGEing and adult health (WHO-SAGE), India wave-2, which was conducted in 2015 in six selected states of India, representing different country regions. The sample included 6,396 older adults aged 50 years and above. We used multivariable linear regression models to examine the associations between sleep quality, sleep duration and cognitive function, separately among older men and women.ResultsOlder men and women with poor sleep and short duration sleep had lower mean scores of cognition than their peers with good sleep and age-appropriate sleep duration. Poor sleep (aCoef: -5.09, CI: -8.66, -1.51) and short duration sleep (aCoef: -5.43, CI: -7.77, -3.10) were negatively associated with cognitive functioning among older men and the associations remained significant among older men with poor sleep (aCoef: -2.39, CI: -3.78, -1.00) and short duration sleep (aCoef: -4.39, CI: -6.46, -2.31) after adjusting for a large number of socio-demographic, health and behavioral factors. Similarly, poor sleep (aCoef: -3.15, CI: -5.79, -0.52) and short duration sleep (aCoef: -2.72, CI: -4.64, -0.81) were associated with cognitive functioning among older women, however, the associations were insignificant when the potential confounders were adjusted.ConclusionsThis study provides evidence for the significant association between sleep health and cognitive functioning in older Indian adults, especially older men, with poor sleep quality and insufficient sleep duration being detrimental to their cognitive health. Healthcare providers should routinely screen for sleep quality and age-appropriate sleep duration in their older adult patients and consider sex/gender-tailored sleep interventions as part of cognitive health management strategies.

Background: Maternal sleep disturbance is a risk factor for adverse outcomes like preterm birth. However, the association of maternal sleep quality and duration with the risk of the infant being small for gestational age (SGA) remains inconclusive, and the specific critical window of vulnerability has yet to be clearly identified. Therefore, this study aims to investigate the effect of maternal sleep quality and duration on the risk of having an SGA infant and to identify the critical window for this association. Methods: One thousand six hundred and seventy-seven participants from the Shenzhen Birth Cohort Study were included. Maternal sleep duration and quality during pregnancy were assessed using the Pittsburgh Sleep Quality Index (PSQI) in early (<19 weeks), mid- (24–28 weeks), and late (32–38 weeks) pregnancy. Multivariate logistic regression analyses were used to examine the association of an SGA infant with sleep duration and quality, along with their specific effects across the different pregnancy stages. Results: The pregnant women with short sleep duration (≤7 h/day) in the early stage of pregnancy appeared to have a higher risk of having an SGA infant (aOR = 1.93, 95% CI = 1.32~2.79). Additionally, poor sleep quality combined with short sleep duration was associated with an even higher risk of having an SGA infant (aOR = 2.08, 95% CI = 1.32~3.23). However, this association was observed only during early pregnancy. Conclusions: The women with short sleep duration were associated with SGA risk, and the early stage of pregnancy might be a particularly sensitive period for this relationship. Addressing maternal sleep problems during pregnancy as part of antenatal care is crucial for reducing the likelihood of having an SGA infant and improving the overall birth outcomes.

Objective/Background: Fewer than one-third of U.S. women meet the Institute of Medicine guidelines for healthy gestational weight gain (GWG). While poor sleep quality and short sleep duration have been associated with weight gain and obesity in the general population, the relationship of sleep with pregnancy weight and body composition changes is unclear. This study aimed to examine associations of sleep duration and quality with pregnancy-related changes in body weight and fat. Participants: Pregnant women obtaining obstetric care through the University of North Carolina at Chapel Hill Healthcare System (UNC) (n = 339 who reported any sleep data) participating in the Pregnancy Eating Attributes Study. Materials and Methods: Participants were recruited at ≤12 weeks gestation and followed through delivery. The Pittsburgh Sleep Quality Index measured sleep duration and quality in early and late pregnancy. Weight was measured at each pregnancy medical visit and skinfolds were measured each trimester. t-tests examined sleep changes from early to late pregnancy and regression analyses estimated associations of sleep quality and duration with GWG and gestational fat gain (GFG). Results: Sleep quality and duration declined across pregnancy. A greater proportion of women with high early pregnancy body mass index (>25) reported low sleep quality and short sleep duration. Sleep quality was not associated with GWG adequacy, whereas longer late pregnancy sleep duration was associated with greater odds of inadequate GWG. Shorter sleep duration and lower sleep quality in late, but not early, pregnancy were associated with greater GFG. Conclusions: Lower sleep quality and shorter sleep duration in late pregnancy were associated with greater GFG. Experimental studies are needed to test the direction of causality between GFG and sleep attributes. ClinicalTrials.gov ID: NCT02217462.

<i>Background</i>: Sleep disorders are known to be linked with numerous cardiovascular comorbidities including type 2 diabetes mellitus. The prevalence and impact of sleep quality and duration on diabetes in the Cameroonian population is not well established. This study evaluates the isolated and combined contribution of two aspects of sleep (duration and quality) on glucose homeostasis in an urban and rural Cameroonian population. <i>Methods</i>: This was a cross-sectional prospective survey conducted among 249 rural and 250 urban community dwellers in Cameroon aged ≥18 years. Self-reported sleep duration (SD) and quality were evaluated using the Pittsburgh Sleep Quality Index (PSQI). Poor sleep quality was considered for PSQI score>5 and short SD was considered≤ 6h. Diabetes was considered for fasting blood glucose>126mg/d Land/or use of glucose-lowering medications. <i>Results</i>: Mean age was 36±12 years, and men accounted for 39.1%. Frequency of poor sleep quality was 50.3% and was similar in urban and rural groups (48.2% vs 52.4% respectively, p=0.395). Short SD was present in 30.5% of subjects and was more frequent among urban dwellers (36.1% vs 24.8% in rural, p=0.006, respectively). Short SD was significantly associated with diabetes (OR 2.62, 95%CI 1.38-5.00). Although the frequency of diabetes was higher in participants with poor sleep quality compared to those with PSQI ≤5 (10% vs 6.5%, respectively), the observed difference was not significant (p>0.05). The combination of poor sleep quality and short SD was strongly associated with diabetes (OR 2.67, 95%CI 1.23-5.79). <i>Conclusion</i>: This survey demonstrates a significant association between short sleep duration as well as the combination of short sleep duration and poor sleep quality with type 2 diabetes prevalence. It is appropriate to consider sleep quality and duration as potentially modifiable variables associated with the presence or management of diabetes in these Cameroonian populations.

The combined effects of sleep and extreme heat exposure on cognitive function among older adults.

Purpose: Short sleep duration and poor sleep quality in middle age have been reported to affect blood pressure(BP) control. However, the association between sleep duration, sleep quality and BP control is controversial in older adults with hypertension taking antihypertensive drugs. The aim of this study was to investigate this association in 70–80-year-old participants in the Japanese study of Septuagenarians, Octogenarians and Nonagenarians Investigation with Centenarians (SONIC). Method: Of the participants in the SONIC study, we performed a cross-sectional analysis of participants with hypertension taking antihypertensive drugs aged 76 ± 1 (n = 242) and 86 ± 1 (n = 196) years who had cooperated in the sleep survey. Sleep duration and quality were evaluated by the Pittsburgh Sleep Quality Index(PSQI). The subjects were categorized as &lt; 6(short) and &gt; = 6 hours. A PSQI&gt; = 6 defined poor sleepers and a PSQI&lt; = 5 defined good sleepers. BP control was defined as average systolic BP &lt; 140mmHg and diastolic BP &lt; 90mmHg as controlled status. We performed the multivariable logistic regression to investigate the association between sleep duration, sleep quality and BP control adjusted for the following confounding factors: age, sex, body mass index, frail, smoking, alcohol consumption, medical history, depressive symptoms separately for each age group. Results: In the age 70 years, logistic regression analysis indicated that neither sleep duration nor sleep quality association BP control. On the other hand, in the age 80 years, sleep duration of &lt; 6 hours was associated with poor BP control(OR = 4.87, 95% CI: 1.54–15.41,P = 0.007) when compared to sleep duration of &gt; = 6 hours and sleep quality was not significantly associated with BP control. Conclusion: In the age 80 years, sleep duration of &lt; 6 hour was associated with poor BP control. These results indicate that adequate sleep may be important for BP control in older adult, especially age around 80 years.

Shortened sleep duration causes hormonal and metabolic changes that favor fat accumulation and weight gain. Obesity, in turn, may reduce sleep quality and contribute to sleep loss. The purpose of this study was to evaluate the sleep durations of individuals with morbid obesity, compared to their nonobese counterparts, and to determine the effects of surgical weight reduction on sleep duration and sleep quality. The study population included 45 bariatric (BA) surgical patients (mean body mass index [BMI] = 49) and 45 gender-matched nonobese controls (NC; BMI = 24). Self-reported sleep durations were obtained and overall sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). The data show that average sleep durations of the preoperative BA patients were significantly (p < 0.0001) less than those of the NC, i.e., 6.0 and 7.2 h, respectively. Sleep loss for the BA patients was associated with poor sleep quality, along with an increased frequency of conditions that interfere with sleep, including coughing and snoring, difficulty breathing, feeling too hot, and experiencing pain. Overall, 78% of the BA patients, compared to 36% of the NC, had PSQI scores indicative of poor sleep quality. Surgery after 3 to 12 months resulted in significant (p < 0.0001) weight loss (percentage total change in BMI = 34) and improved sleep quality, i.e., PSQI = 8.8 preoperatively vs. 4.6 postoperatively. Sleep durations increased significantly (p < 0.0001) post-surgery from 6.0 to 6.8 h. Individuals with extreme obesity, compared to the nonobese, obtain less sleep and experience poorer sleep quality. Bariatric surgery improves sleep duration and quality.