Elevated oxidative stress biomarkers in adults with segmented sleep patterns.

STUDY OBJECTIVES: We investigated the association between different sleep patterns and inflammatory and oxidative stress biomarkers in adults. METHODS: A total of 321 consented adults who fulfilled the inclusion criteria were recruited in this cross-sectional study. The inclusion criteria were mainly based on apparently healthy adults aged 18-59 years. To identify sleep patterns, participants were requested to wear the actigraph for 1 week for 24 hours a day. Fasting blood was collected from each participant at day 8. The blood serum was analyzed for inflammatory and oxidative stress biomarkers. Sleep patterns were defined as monophasic (1 episode of night sleep) biphasic (2 episodes of sleep; night and aternoon siesta), and polyphasic sleep pattern (3 or more sleep episodes). RESULTS: There was no correlation between night sleep duration, total sleep in 24 hours, and napping among inflammatory and oxidative stress biomarkers: high-sensitivity C-reactive protein, malondialdehyde, total glutathione, and basal oxidizability status. Actigraphy reports showed 3 sleep patterns in this cohort, monophasic (24.3%), biphasic-napping (45.2%) and polyphasic (30.5%). Individuals with segmented sleep patterns were significantly associated with oxidative stress biomarkers. A polyphasic sleep pattern was significantly associated with higher basal oxidizability status (P = .023), whereas a biphasic sleep pattern showed higher malondialdehyde (P = .036) as compared to a monophasic sleep pattern. Total glutathione was significantly higher in monophasic sleepers (P = .046). There was no difference in serum high-sensitivity C-reactive protein among all sleep patterns. CONCLUSIONS: Segmented sleep in polyphasic and biphasic sleep patterns is associated with higher serum malondialdehyde and basal oxidizability status in particular. Further studies are recommended on the cardiometabolic impact of oxidative stress biomarkers in individuals with segmented sleep. CITATION: Al Lawati I, Zadjali F, Al-Abri MA. Elevated oxidative stress biomarkers in adults with segmented sleep patterns. J Clin Sleep Med. 2024;20(6):959-966.

Seasonal variation and sleep patterns in a hot climate Arab Region.

PURPOSE: To describe the effect of seasonal variations on sleep patterns in a hot climate Arab region. METHODS: This is a cross-sectional study that included healthy Omani subjects of both genders between ages 18 and 59 years. Data for sleep pattern identification in summer and winter were collected from participants using an actigraphy wristband. RESULTS: Among 321 participants, in summer seasons, a polyphasic sleep pattern (40%) prevailed over other sleep patterns (P < 0.001). While in the winter season, monophasic sleep (31%) was the dominant pattern (P < 0.001). Subjects slept longer during the winter seasons with total hours of sleep during the day 48 min longer than in the summer, though the difference was not statistically significant (P > 0.05), while siesta duration in the summer was significantly longer (13 min, P < 0.01). In summer, the sleep quality was good (PSQI ≤ 5); however, it was poor (PSQI > 5) in winter (P < 0.05). Night sleep duration, daytime sleepiness, and sleep latency were not statistically different between the summer and winter seasons. CONCLUSION: Sleep patterns may be influenced by seasonal changes. A polyphasic sleep pattern prevailed in summer while a monophasic pattern was the predominant sleep pattern in winter. In summer, the sleep quality was good and the siesta duration was longer compared to the winter.

Association of elevated glycated hemoglobin and obesity with afternoon napping for more than 1 h in young and middle-aged healthy adults.

Introduction: Sleep has different patterns followed worldwide and can be influenced by social, cultural, and environmental factors. Daytime napping is commonly practiced in different parts of the world with controversial results of its effect on glucose metabolism. The current study aims to examine the association of afternoon napping and night sleep duration with metabolic derangements. Methods: This is a cross-sectional study involving young adults and middle-aged subjects. Anthropometric measurements were taken for height and weight and hip and waist ratio. Consented subjects were asked to wear actigraphy for 1 week and run their usual daily activities. Home sleep apnea testing was performed to exclude obstructive sleep apnea. Subjects had been asked to come fasting on day seven for blood collection to test for fasting glucose, glycated hemoglobin, lipid profile, and insulin. Results: A total of 405 subjects were involved to complete the study (52% male, 48% female). The mean age of participants was 32.8 ± 11.5 years. The study indicated that the duration of afternoon napping was significantly associated with abnormal glycated hemoglobin (HbA1c > 5.7%) (p = 0.01) and body mass index (p = 0.046) independent of age, gender, and nocturnal sleep duration. Nocturnal sleep duration was associated with increased insulin level (p = 0.04). Conclusion: Afternoon napping is associated with an increased level of glycated hemoglobin and obesity and that may predispose to the development of type 2 diabetes mellitus.

Agreement analysis of sleep patterns between self-reported questionnaires and actigraphy in adults.

PURPOSE: To investigate the agreement in sleep pattern recording by self-reported sleep questionnaires and actigraphy in adults. METHODS: This is a cross-sectional study. Men and women who met inclusion criteria were recruited for this study. The inclusion criteria were apparently healthy Omani nationals ages 19 to 50 years. Sleep questionnaires were randomly distributed in Muscat either directly or via electronic and paper announcements. Data were collected from the participants using the self-reported questionnaires with four piloted questions for sleep pattern identification and through the actigraphy wristband given to subjects to wear for a week. Cohen's kappa test was performed for agreement analysis. RESULTS: A total of 964 Omani subjects between ages 18 and 59 years of both genders were recruited and completed the questionnaires successfully. Out of these, only 321 subjects wore the actigraphy wristband for 1 week (response rate = 33%). Agreement analysis reported a mild level of agreement for the monophasic (41%), moderate level for biphasic (59%), and good level for polyphasic (70%) sleep patterns. The overall agreement level of sleep patterns between the two methods was 57%. There is a low specificity of self-reported assessment in reporting sleep pattern. CONCLUSION: The average agreement level of subjective versus objective assessments of sleep patterns was moderate at 57% and self-reported sleep pattern is not specific. The study recommends the use of actigraphy along with sleep questionnaires for accurate assessment of sleep patterns in cohort studies.

Sleep Patterns and Quality in Omani Adults.

BACKGROUND: Sleep patterns have changed continuously worldwide and it can be influenced by social, cultural, and environmental factors. These patterns may be associated with poor sleep quality and daytime sleepiness. The aim of the study was to investigate sleep patterns and quality in Omani adults using actigraphy. SUBJECTS AND METHODS: This was a cross-sectional study conducted between June 2015 and February 2017. Four hundred subjects agreed to participate in the study (52% male, 48% female). Subjects were randomly selected and enrolled in the study among young adults and middle aged individuals living in the City of Muscat. Subjects were asked to fill-in Epworth sleepiness scale (ESS) and Pittsburgh sleep quality index (PSQI). Actigraphy was used to measure their sleep patterns for one week. RESULTS: The mean age of participants was 32.80±11.50 years. Four sleep patterns were identified: monophasic, bi-phasic (post-dawn), bi-phasic (afternoon siesta), and polyphasic (three sleep periods/24 hours). The study revealed that 35% of participants had biphasic-siesta sleep pattern, 28% polyphasic, 26% monophasic, and 11% biphasic-dawn. The biphasic siesta pattern was found to be associated with younger age group (25-34 years) (P=0.001). Polyphasic sleep was associated with higher ESS score (P=0.001) but not with poor sleep quality (P=0.24). There was no significant difference in night sleep duration among all the sleep patterns (P=0.07) but the polyphasic sleep pattern had higher total 24-hour day sleep duration (P=0.03). Nearly 90% of participants practiced afternoon siestas with mean duration of 45±43 minutes. CONCLUSION: The predominant sleep pattern among Omanis was biphasic-siesta and majority of people practiced afternoon siesta. Polyphasic sleep pattern is associated with daytime sleepiness.