Search Results (55)

Sleep is a vital physiological process for recovery and health. In people with knee osteoarthritis (OA), disrupted sleep is common and linked to worse clinical outcomes. Commercial sleep trackers provide an accessible option to monitor sleep in this population, but their accuracy for detecting sleep, wake, and sleep stages remains uncertain. This study compared nighttime sleep data from polysomnography (PSG) and Fitbit Sense in individuals with knee OA and insomnia. Data were collected from 53 participants (60.4% women, mean age 51 ± 8.2 years) over 62 nights using simultaneous PSG and Fitbit recording. Fitbit Sense showed high accuracy (85.76%) and sensitivity (95.95%) for detecting sleep but lower specificity (50.96%), indicating difficulty separating quiet wakefulness from sleep. Agreement with PSG was higher on nights with longer total sleep time, higher sleep efficiency, shorter sleep onset, and fewer awakenings, suggesting better performance when sleep is less fragmented. The device showed limited precision in classifying sleep stages, often misclassifying deep and REM sleep as light sleep. Despite these issues, Fitbit Sense may serve as a useful complementary tool for monitoring sleep duration, timing, and regularity in this population. However, sleep stage and fragmentation data should be interpreted cautiously in both clinical and research settings. Full article

Currently, approximately 40% of patients with dementia develop some form of sleep disorder. Benzodiazepines are widely prescribed but pose the risk of tolerance and cognitive decline; however, Z-drugs may offer safer alternatives. Therefore, this systematic review aimed to analyze the effect of benzodiazepines and Z-drugs on sleep disorders in patients with dementia. Two authors conducted a systematic search in PubMed, Scopus, Web of Science, Espistemonikos, and ACCESSSS for studies published between 2019 and 2024 using the MeSH terms “dementia”, “sleep disorders”, and “pharmacotherapy”. Randomized clinical trials comparing benzodiazepines, Z-drugs, or innovative medications with placebo or other drugs were included. Sleep and cognitive outcomes were assessed using validated instruments; the ROB-2 tool evaluated the risk of bias. The protocol was registered in “PROSPERO”. Three randomized clinical trials involving a total of 192 patients were included in the review. Zopiclone increased the main duration of nighttime sleep by 81 min, Zolpidem reduced nighttime awakenings by 21 min, and Eszopiclone improved sleep quality, benefited the progression of sleep architecture, and reduced mental symptoms such as fear and anxiety. Z-drugs show superior efficacy and safety over benzodiazepines, improving sleep and cognitive symptoms in dementia. Personalized treatment and further research across dementia subtypes are needed to optimize long-term outcomes. Full article

Introduction/Aim: Type 1 diabetes (T1D) challenges glycemic control, with sleep disturbances affecting insulin sensitivity and glucose variability. This study aimed to observe sleep quality in T1D patients and glycemic outcomes, particularly at bedtime hours. Methods: This retrospective observational study, conducted at an Italian clinical center, included T1D patients using Medtronic devices. Sleep quality was assessed using the Italian version of the Pittsburgh Sleep Quality Index (PSQI), and glycemic outcomes were analyzed with CGM data. Descriptive statistics and non-parametric tests were applied for statistical comparisons. Results: Of 45 patients, four were excluded, leaving 41 for analysis. The mean PSQI score was 6.0 ± 4.1, with 36.6% showing poor sleep quality. No significant differences in age, sex, BMI, or diabetes duration were found. Poor sleepers had a higher time above range level 2 (TAR2) (6.3 ± 6.2%) compared to good sleepers (4.1 ± 5.0%). During bedtime hours, poor sleepers showed a significantly higher TAR2 (6.7 ± 7.2% vs. 3.3 ± 6.2%, p = 0.013). Conclusions: Poor sleep quality is associated with increased nocturnal hyperglycemia in T1D patients. Enhancing sleep quality may contribute to improved glycemic control, particularly during nighttime. Future research should explore targeted sleep interventions in diabetes care, and specific lifestyle-based healthcare programs are recommended to optimize glycemic outcomes. Full article

Background/Objectives: Active gamification, which incorporates game elements with physical interaction, is presented as an innovative strategy to address anxiety problems and sleep quality in children. This study aimed to evaluate the impact of an active gamification program on the aforementioned variables in children in primary education. Methods: This study utilized a randomized, controlled trial with 120 children between 8 and 11 years of age, divided into an experimental group, which participated in a 12-week gamified program, and a control group, which continued with traditional physical education classes. Results: The main findings indicate that the intervention had a significant impact on reducing anxiety, with improvements in most of the subscales evaluated except for the obsessive-compulsive disorder subscale. Significant improvements were also found in sleep quality, with reductions in bedtime resistance, nighttime awakenings, parasomnias, and sleep-disordered breathing, although no significant changes were noted in sleep-onset delay, sleep duration, sleep anxiety, and daytime sleepiness. Conclusions: The gamification intervention in physical exercise showed positive effects in reducing anxiety and improving sleep quality in primary school children, highlighting its potential as an intervention strategy in primary education classrooms. Full article

Cardiology and sleep societies recommend 7–9 h sleep/night for adults (7–8 h for seniors) and more for youngsters; nonetheless, short sleep duration (SSD) of <7 h/night is epidemic. We searched PubMed for representative investigations, including those cited by meta-analyses, that reported association between SSD and long sleep duration (LSD) of >9 h/night and blood pressure (BP) levels to assess shortcomings of their methods. Studies indicate both SSD and LSD negatively impact BP despite major deficiencies, such as (i) reliance mainly on cross-sectional rather than longitudinal protocols, (ii) inclusion of participants diagnosed with hypertension (HTN) and/or taking antihypertension medications, (iii) assessment of BP and diagnosis of HTN performed by single wake-time office measurement rather than multiple measurements performed by 24 h ambulatory BP monitoring (ABPM), and (iv) determination of SD by subjective recall, single-night polysomnography, or diary recordings rather than objective wrist actigraphy of sufficient duration. The limited number of ABPM-based studies, despite evidencing major shortcomings, particularly (i) assessment for 24 h rather than preferred ≥48 h and (ii) inclusion of subjects diagnosed with HTN and/or taking antihypertension medications, also report association between abnormal SD and elevated 24 h ‘daytime’/wake-time diastolic and systolic (SBP) means plus ‘nighttime’/sleep-time SBP mean and dipping—the latter two indices, in combination, the strongest predictors of major adverse cardiovascular events. Full article

Sleep disorders in children have a negative impact on mental and physical development, and a lack of sleep is one of the most important problems in infancy. At the age when naps are commonly accepted, the judgment of whether the amount of sleep is adequate has been based on the total amount of sleep per day. In other words, the idea is that even if the amount of sleep at night is insufficient, it is not considered insufficient if it is compensated for by taking a long nap or sleeping late on weekend mornings. However, these lifestyle habits disrupt the circadian rhythm and cause social jet lag, which is not appropriate for healthy mental and physical development. Therefore, in this review, I present the average required nighCime basic sleep duration (NBSD) of 10 h for Japanese and 11 h for Caucasian children as a judgment standard. (1) If the child sleeps less than 8 h at night, and (2) if the child sleeps less than 9 h at night or 30 to 60 min less than the required NBSD, immediate treatment is recommended. I also discuss briefly how to address sleep insufficiency in childhood. Full article

Cardiovascular diseases are a major cause of mortality worldwide. Long-term monitoring of nighttime heart rate (HR) and heart rate variability (HRV) may be useful in identifying latent cardiovascular risk. The Oura Ring has shown excellent correlation only with ECG-derived HR, but not HRV. We thus assessed if stringent data quality filters can improve the accuracy of time-domain and frequency-domain HRV measures. 92 younger (<45 years) and 22 older (≥45 years) participants from two in-lab sleep studies with concurrent overnight Oura and ECG data acquisition were analyzed. For each 5 min segment during time-in-bed, the validity proportion (percentage of interbeat intervals rated as valid) was calculated. We evaluated the accuracy of Oura-derived HR and HRV measures against ECG at different validity proportion thresholds: 80%, 50%, and 30%; and aggregated over different durations: 5 min, 30 min, and Night-level. Strong correlation and agreements were obtained for both age groups across all HR and HRV metrics and window sizes. More stringent validity proportion thresholds and averaging over longer time windows (i.e., 30 min and night) improved accuracy. Higher discrepancies were found for HRV measures, with more than half of older participants exceeding 10% Median Absolute Percentage Error. Accurate HRV measures can be obtained from Oura’s PPG-derived signals with a stringent validity proportion threshold of around 80% for each 5 min segment and aggregating over time windows of at least 30 min. Full article

In this study, we investigated the sleep–wake rhythm of nursery school children with the aim of supporting their health and mental/physical development. We analyzed 4881 children from infancy to 6 years of age, using 2 week sleep tables recorded by their guardians. The tables contained night bedtimes, wake times, nighttime/daytime sleep duration, and the differences in these between weekdays and weekends. The total sleep decrement of children with increasing age is attributed to a decrease in daytime sleep, while nighttime sleep duration remains almost unchanged at about 10 h, which is, therefore, referred to as the nighttime basic sleep duration (NBSD). Although bedtime stabilizes at around 9:30 p.m. by the age of 2, wake-up times tend to be before 7 a.m., which results in sleep insufficiency during weekdays. This lack of sleep is compensated for by long naps on weekdays and by catching up on sleep on weekend mornings, which may contribute to future social jet lag. Guardians are encouraged to know their children’s exact NBSD and set an appropriate bedtime to be maintained on weekdays. This helps to prevent sleep debt and fosters a consistent daily rhythm of waking up at the same time both on weekdays and weekends. These conditions are believed to support mental/physical development and school and social adaptation. Full article

Background: Caffeine is a well-known psychostimulant reputed to alleviate the deleterious effects of sleep deprivation. Nevertheless, caffeine can alter sleep duration and quality, particularly during recovery sleep. We evaluated the effects of acute caffeine intake on the duration and quality of recovery sleep following total sleep deprivation (TSD), taking into account daily caffeine consumption. Methods: Forty-one participants performed a double-blind, crossover TSD protocol (38 h of continuous wakefulness) with acute caffeine or placebo. Caffeine (2.5 mg/kg) or placebo was administered twice during continuous wakefulness (last treatment 6.5 h before bedtime for the recovery night). Polysomnographic measurements were recorded using a connected headband. Results: TSD was associated with a rebound in total sleep time (TST) on the recovery night (+110.2 ± 23.2 min, p < 0.001). Caffeine intake decreased this recovery TST (−30.2 ± 8.2 min p = 0.02) and the N3 sleep stage duration (−35.6 ± 23.2 min, p < 0.01). Caffeine intake altered recovery sleep continuity (increased number of long awakenings), stability (higher stage transition frequency), and organization (less time spent in complete sleep cycle) and decreased the delta power spectral density during NREM sleep. On the recovery night, habitual daily caffeine consumption was negatively correlated with TST in caffeine and placebo conditions and positively correlated with wake after sleep onset (WASO) duration and with the frequency of long (>2 min) awakenings in the caffeine condition only. Conclusions: Acute caffeine intake during TSD affects nighttime recovery sleep, with an interaction with daily consumption. These results may influence advice on caffeine intake for night-shift workers. (NCT03859882). Full article

Objectives: Eating disorders (EDs) have emerged as a growing public health concern. However, the role of sleep in this context remains underexplored. The aim of this cross-sectional study was to determine the associations between sleep parameters and chronotype with ED risk in a sample of university students in Spain. Methods: ED risk was assessed via the Sick, Control, One stone, Fat, Food Questionnaire, and sleep quality was assessed via the Pittsburgh Sleep Quality Index. Other sleep parameters and chronotypes were self-reported. Sociodemographic, body composition, lifestyle, and depressive symptom data were collected. Logistic and linear regression models adjusted for the main confounders were used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of the study associations. Results: A total of 403 students (70.2% female) aged 18 to 30 years participated in the study. Those reporting poor sleep quality (OR = 1.85, 95% CI 1.08–3.17, p = 0.025) and ≤6 h of night-time sleep duration (OR = 4.14, 95% CI 2.00–8.57, p < 0.01) were more likely to be at risk of EDs in the adjusted analyses. The association between night-time sleep duration and the risk of ED did not remain significant when we adjusted for sleep quality. In addition, an evening chronotype was associated with an increased risk of EDs (OR = 1.68, 95% CI 1.07–2.66, p = 0.039) only before adjustment for confounders. Conclusions: Among university students, poorer sleep quality was cross-sectionally associated with EDs. Future prospective studies are needed to examine whether promoting sleep quality may serve as an effective strategy for preventing the risk of EDs. Full article

The aim of our cross-sectional and longitudinal study is to assess the relationship between daytime and night-time sleep duration and health-related quality of life (HRQoL) in adults with metabolic syndrome after a 1-year healthy lifestyle intervention. Analysis of the data from 2119 Spanish adults aged 55–75 years from the PREDIMED-Plus study was performed. Sleep duration was assessed using a wrist-worn accelerometer. HRQoL was measured using the SF-36 questionnaire. Linear regression models adjusted for socioeconomic and lifestyle factors and morbidity were developed. In cross-sectional analyses, participants with extreme night-time sleep duration categories showed lower physical component summary scores in Models 1 and 2 [β-coefficient (95% confidence interval) <6 h vs. 7–9 h: −2, 3 (−3.8 to −0.8); p = 0.002. >9 h vs. 7–9 h: −1.1 (−2.0 to −0.3); p = 0.01]. Participants who sleep less than 7 h a night and take a nap are associated with higher mental component summary scores [β-coefficient (95% confidence interval) 6.3 (1.3 to 11.3); p = 0.01]. No differences between night-time sleep categories and 12-month changes in HRQoL were observed. In conclusion, in cross-sectional analyses, extremes in nocturnal sleep duration are related to lower physical component summary scores and napping is associated with higher mental component summary scores in older adults who sleep less than 7 h a night. Full article

Background: Cyberbullying and nighttime phone use are independently detrimental to sleep and psychological wellbeing, but whether in combination they might be more disruptive remains unknown. Methods: Students aged 7–19 years (N = 53,734) completed a survey measuring sleep duration, nighttime phone use, cyberbullying, and psychological distress. Results: Across stratification variables of gender (F/M) and age group (primary/secondary-school-aged children), bivariate ordered probit regression revealed that being cyberbullied and nighttime phone use were independent predictors of both increased psychological distress and obtaining <8 h sleep. Nighttime phone use was observed to moderate the relationship between cyberbullying and sleep in both primary- and secondary-school-aged girls and boys and, likewise, between cyberbullying and psychological distress, especially in secondary-school-aged boys. Notably, the moderation effect was such that the impact of nighttime phone use was lower in children who were compared with those who were not cyberbullied. This may be a ceiling effect due to the high number of cyberbullied children reporting shortened sleep and higher levels of psychological distress. Discussion: The present findings point to a possible role of nighttime phone use as a moderator of the effect of cyberbullying on sleep and psychological wellbeing. There is a need for future studies to better explore more directly the effects of cyberbullying during the nighttime. Full article

Background: The sleep-low method has been proposed as a way to sleep in a low-glycogen state, increase the duration of low glycogen availability and sleep and temporarily restrict carbohydrates to improve exercise performance. However, long-term dietary restriction may induce mental stress in athletes. Therefore, if it can be shown that the effects of the sleep-low method can be achieved by restricting the carbohydrate intake at night (the nighttime carbohydrate restriction method), innovative methods could be developed to reduce weight in individuals with obesity and enhance athletes’ performance with reduced stress and in a shorter duration when compared with those of previous studies. With this background, we conducted a study with the purpose of examining the intervention effects of a short-term intensive nighttime carbohydrate restriction method. Methods: A total of 22 participants were recruited among university students participating in sports club activities. The participants were assigned at random to groups, including a nighttime carbohydrate restriction group of 11 participants (6 males, 5 females; age 22.3 ± 1.23) who started a carbohydrate-restricted diet and a group of 11 participants (5 males, 6 females; age 21.9 ± 7.9) who continued with their usual diet. The present study had a two-group parallel design. In the first week, no dietary restrictions were imposed on either group, and the participants consumed their own habitual diets. In the second week, the total amount of calories and carbohydrate intake measured in the first week were divided by seven days, and the average values were calculated. These were used as the daily calorie and carbohydrate intakes in the second week. Only the nighttime carbohydrate restriction group was prohibited from consuming carbohydrates after 4:00 p.m. During the two-week study period, all participants ran for one hour each day before breakfast at a heart rate of 65% of their maximum heart rate. Results: The results obtained from young adults participating in sports showed significant differences in peak oxygen consumption ($\stackrel{·}{\mathrm{V}}$O2peak), work rate max, respiratory quotient (RQ), body weight and lean body mass after the intervention when compared with before the intervention in the nighttime carbohydrate restriction group (p < 0.05). Conclusions: Our findings suggest that the nighttime carbohydrate restriction method markedly improves fat metabolism even when performed for a short period. This method can be used to reduce body weight in individuals with obesity and enhance athletes’ performance. However, it is important to consider the intake of nutrition other than carbohydrates. Full article

AIM: Congenital Zika Virus Syndrome (CZS) presents notable hurdles to neurodevelopment, with language development emerging as a crucial aspect. This study investigates sleep patterns and language skills in children with CZS, aiming to explore the potential synchronization of sleep development with their neurodevelopment. METHOD: We studied cross-sectionally 135 children with CZS aged 0 to 48 months, investigating sleep using the BISQ Questionnaire. Language development was assessed using the Early Language Milestone Scale, while motor development and cognitive and social ability were assessed using the Bayley Scales of Infant and Young Child Development 3rd edition. We also studied longitudinally a cohort of 16 children (initially aged 0 to 12 months) whom we followed for four years, assessing at one-year intervals. RESULTS: Sleep disturbances and language deficits were highly frequent in this population. In the 0–12 months group, a late bedtime and frequent nighttime awakenings were associated with poorer auditory expressive skills. At 13–24 months, nighttime awakenings were associated with poorer auditory expressive skills, while among 25–36-month-olds decreased auditory receptive skills were associated with longer sleep onset latency and reduced nighttime sleep duration. CONCLUSION: The brain alterations caused by Zika virus infection affect both sleep disturbances and delays in language development. It is possible that sleep disturbance may be a mediating factor in the pathway between CZS and delayed language development, as the three analyzed language skills showed a correlation with sleep parameters. Full article

Objectives: Nocturnal blood pressure (BP) monitoring is essential for evaluating cardiovascular risk and guiding treatment decisions. However, the standardized narrow-fixed nighttime period between 10 p.m. and 6 a.m. may not accurately reflect individual sleep schedules. This pilot study aimed to investigate the comparability between the standardized nighttime period and actual time in bed (TIB) regarding BP assessment. Further, our goal was to evaluate the clinical relevance of the observed BP differences. Methods: A total of 30 participants underwent 24 h ambulatory blood pressure monitoring (ABPM). Patient-specific TIB was precisely assessed through an accelerometer and a position sensor from the SOMNOtouch NIBP™ (SOMNOmedics GmbH, Randersacker, Germany). We analysed the effect of considering individual TIB as nighttime instead of the conventional narrow-fixed interval on the resulting nocturnal BP levels and dipping patterns. Results: We observed differences in both systolic and diastolic BP between the standardized nighttime period and the TIB. Furthermore, a notable percentage of patients (27%) changed their dipping pattern classification as a function of the nighttime definition adopted. We found strong correlations between the start (r = 0.75, p < 0.01), as well as the duration (r = −0.42, p = 0.02) of TIB and the changes in dipping pattern classification. Conclusions: Definition of nocturnal period based on the individual TIB leads to clinically relevant changes of nocturnal BP and dipping pattern classifications. TIB is easily detected using a body position sensor and accelerometer. This approach may thus improve the accuracy of cardiovascular risk evaluation and enhance treatment strategies. Full article