Microbiota Metabolite Profiles and Dietary Intake in Older Individuals with Insomnia of Short vs. Normal Sleep Duration.

Recent evidence suggests that the gut microbiota plays a role in insomnia pathogenesis. This study compared the dietary habits and microbiota metabolites of older adults with insomnia of short vs. normal sleep duration (ISSD and INSD, respectively). Data collection included sleep assessment through actigraphy, dietary analysis using the Food Frequency Questionnaire, and metabolomic profiling of stool samples. The results show that ISSD individuals had higher body mass index and a greater prevalence of hypertension. Significant dietary differences were observed, with the normal sleep group consuming more kilocalories per day and specific aromatic amino acids (AAAs) phenylalanine and tyrosine and branch-chain amino acid (BCAA) valine per protein content than the short sleep group. Moreover, metabolomic analysis identified elevated levels of the eight microbiota metabolites, benzophenone, pyrogallol, 5-aminopental, butyl acrylate, kojic acid, deoxycholic acid (DCA), trans-anethole, and 5-carboxyvanillic acid, in the short compared to the normal sleep group. The study contributes to the understanding of the potential role of dietary and microbial factors in insomnia, particularly in the context of sleep duration, and opens avenues for targeted dietary interventions and gut microbiota modulation as potential therapeutic approaches for treating insomnia.

Insomnia Severity Mediates the Association between COVID-19 Related Anxiety and Increase in Tobacco Smoking During the COVID-19 Pandemic among Adults.

OBJECTIVES: Examining the associations of COVID-19 related anxiety and insomnia with increased smoking following the outbreak of the COVID-19 pandemic, and investigating whether increased insomnia severity mediates the association between COVID-19 related anxiety and increased smoking. METHODS: 598 participants, aged 18-40, out of whom 140 self-identified as smokers, completed online questionnaires during the third wave of the COVID-19 pandemic. Measures included two items assessing COVID-19 related anxiety, the Pittsburgh Sleep Quality Index, and the Insomnia Severity Index, which included a pre-pandemic retrospective report. RESULTS: Compared with nonsmokers, smokers reported lower sleep quality and more severe symptoms of insomnia. Among smokers, more severe symptoms of insomnia were associated with greater odds of increased smoking during the COVID-19 outbreak. COVID-19 related anxiety was indirectly associated with greater odds of increased smoking through greater insomnia severity during the COVID-19 outbreak, after controlling for pre-pandemic levels of insomnia. CONCLUSIONS: Smokers experienced more sleep difficulties during the COVID-19 pandemic than nonsmokers. The results also lend support to the suggestion that anxiety, such that was experienced during the COVID-19 pandemic, may lead to further exacerbation of sleep difficulties, leading in turn to increase in smoking. These findings have important clinical implications that may be particularly relevant to attempts to minimize smoking during stressful circumstances.

Variation in Gut Microbiota Composition is Associated with Sleep Quality and Cognitive Performance in Older Adults with Insomnia.

Purpose: Insomnia, a chronic condition affecting 50% of older adults, is often accompanied by cognitive decline. The mechanism underlying this comorbidity is not fully understood. A growing literature suggests the importance of gut microbiota for brain function. We tested associations between sleep quality and cognitive performance with gut microbiota in older adults with insomnia. Patients and Methods: Seventy-two older adults with insomnia (age 73.2 ± 5.73 years, 56 females) provided stool samples for gut microbial sequencing. Microbiota profile was determined using the DADA2 bioinformatics pipeline. Cognition was assessed with the Cambridge Neuropsychological Test Automated Battery. Objective sleep quality was monitored by a two-week actigraphic recording, and participants completed the Insomnia Severity Index (ISI). We used partial canonical correspondence analysis (pCCA) to examine the relative contribution of insomnia, based on actigraphic sleep efficiency (SE) and ISI, and of cognitive status, based on the Multitasking test of Median Reaction Latency (MTTLMD) and the Spatial Working Memory Between Errors (SWMBE), to variance in microbiota composition. We used Pearson correlations to correlate insomnia and cognitive status parameters with microbiota amplicon sequence variants, genera, and families. Results: The pCCA revealed that sleep quality and cognitive performance explained a variation of 7.5-7.9% in gut microbiota composition in older adults with insomnia. Correlation analysis demonstrated that Lachnoclostridium (genus) correlates positively with SE (r=0.42; P=0.05) and negatively with MTTLMD (r=-0.29; P=0.03), whereas Blautia (genus) correlates negatively with MTTLMD (r=-0.31; P=0.01). Conclusion: Findings demonstrate the associations of sleep quality and cognitive performance with variance in gut microbiota composition and with specific genus abundance in older adults with insomnia. Further studies should validate the findings, determine causal relationships, and evaluate potential interventions for the comorbidity of insomnia and cognitive impairment in older adults with insomnia.

Associations Between Childhood Stressors, COVID-19-Related Anxiety, and Sleep Quality of Adults During the Third Wave of the COVID-19 Pandemic in Israel.

Purpose: Studies point to a persistent effect of the COVID-19 pandemic on sleep quality and mental health, including anxiety. Exposure to stressors during childhood increases the susceptibility to anxiety in later life. Given the negative effects of anxiety on sleep quality, the present study aimed to examine the associations between various childhood stressors and poor sleep quality of adults during the COVID-19 pandemic, and whether these associations are mediated by COVID-19-related anxiety. Participants and Methods: A total of 586 participants aged 18-40 (mean age 27.53± 6.48 years, 301 females) were recruited to take part in an online survey conducted in Israel between February 7 and 15, 2021, during the third wave of the COVID-19 pandemic. Participants completed questionnaires assessing retrospectively adverse childhood experiences (ACEs), childhood harshness (indexed separately by exposure to morbidity and mortality and low socioeconomic status, SES), and childhood unpredictability. COVID-19-related anxiety was assessed using two items. Sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI), and insomnia symptoms with the Insomnia Severity Index (ISI). Participants were asked to complete the ISI concerning two time points: (a) retrospectively, before the COVID-19 outbreak, and (b) currently, during the pandemic. Results: Path analysis indicated that poor sleep quality (PSQI) was directly and indirectly (through COVID-19-related anxiety) predicted by the number of ACEs and childhood morbidity-mortality exposure, directly predicted by childhood low SES, and indirectly predicted by childhood unpredictability. Insomnia symptoms increase (ISI) was indirectly predicted by the number of ACEs, childhood morbidity-mortality exposure, and childhood unpredictability. Conclusion: ACEs as well as harsh and unpredictable childhood environments are predictive of poorer sleep during the COVID-19 pandemic. COVID-19-related anxiety mediates the effects of childhood stressors (other than low SES) on sleep. These findings may have clinical implications relevant to stressful periods in general.

Maternal insomnia and depressive symptoms and early childhood sleep among Arab and Jewish families in Israel.

OBJECTIVES: The present study explored the links between maternal insomnia symptoms, maternal depressive symptoms, and young children's sleep quality among two major cultural groups in Israel: Arab and Jewish. We also assessed the prevalence of maternal insomnia and depressive symptoms, in both cultural groups. METHODS: Mothers of 497 healthy, typically developing infants and toddlers, ranging in age from 3-36 months, participated in the study: 253 of the mothers were Arab and 244 were Jewish. Mothers completed the Insomnia Severity Index (ISI), the Edinburgh Postnatal Depression Scale (EPDS), and the Brief Infant Sleep Questionnaire. RESULTS: For both cultural groups, there were significant positive associations between maternal ISI and EPDS, as well as between maternal ISI and child sleep variables (nighttime wakefulness and perceived child's sleep problems), after controlling for child age. Significant correlations were also found between maternal EPDS and child sleep, after controlling for child age, but these correlations were not significant once controlling for ISI. Cross-cultural differences in prevalence of insomnia and depressive symptoms were found based on the clinical cutoffs of the ISI and EPDS: Arab mothers, compared to Jewish mothers, reported higher levels of insomnia and depressive symptoms, and were more likely to have scores higher than the clinical cutoff on both measures. CONCLUSION: Maternal insomnia, depressive symptoms, and child sleep quality are significantly intertwined in both Arab and Jewish families in Israel. The findings highlight the importance of taking these three domains into consideration in research and in clinical assessments of families with young children.

The effect of co-dependent (thinking in motion [TIM]) versus single-modality (CogniFit) interventions on cognition and gait among community-dwelling older adults with cognitive impairment: a randomized controlled study.

BACKGROUND: Cognition and motor skills are interrelated throughout the aging process and often show simultaneous deterioration among older adults with cognitive impairment. Co-dependent training has the potential to ameliorate both domains; however, its effect on the gait and cognition of older adults with cognitive impairment has yet to be explored. The aim of this study is to compare the effects of the well-established single-modality cognitive computerized training program, CogniFit, with "Thinking in Motion (TIM)," a co-dependent group intervention, among community-dwelling older adults with cognitive impairment. METHODS: Employing a single-blind randomized control trial design, 47 community-dwelling older adults with cognitive impairment were randomly assigned to 8 weeks of thrice-weekly trainings of TIM or CogniFit. Pre- and post-intervention assessments included cognitive performance, evaluated by a CogniFit battery, as a primary outcome; and gait, under single- and dual-task conditions, as a secondary outcome. RESULTS: CogniFit total Z scores significantly improved from baseline to post-intervention for both groups. There was a significant main effect for time [F (1, 44) = 17.43, p < .001, ηp2 = .283] but not for group [F (1, 44) = 0.001, p = .970]. No time X group interaction [F (1, 44) = 1.29, p = .261] was found. No changes in gait performance under single and dual-task performance were observed in both groups. CONCLUSIONS: The findings show that single-modality (CogniFit) and co-dependent (TIM) trainings improve cognition but not gait in older adults with cognitive impairment. Such investigations should be extended to include various populations and a broader set of outcome measurements. TRIAL REGISTRATION: ACTRN12616001543471. Date: 08/11/2016.

Increased physical activity improves gut microbiota composition and reduces short-chain fatty acid concentrations in older adults with insomnia.

Physical activity (PA) can improve functional abilities, well-being, and independence in older adults with insomnia. Studies have shown that PA may be linked to changes in the gut microbiota composition and its metabolites' concentrations. This association among older adults with insomnia, however, is yet to be determined. We explored the relationships between physical activity (PA) levels, gut microbiota composition, and short-chain fatty acid (SCFA) levels in this population. Forty-nine community-dwelling adults with insomnia symptoms, aged 65 and older, participated in this study. Their average daily step-count and sleep continuity measures over a two-week period were calculated based on Actigraphic recordings. Each participant provided fecal samples for the microbiome and SCFA analyses, anthropometric measures, and information via questionnaires on medical history and food consumption. The gut microbiota composition and SCFA concentrations were determined by next-generation sequencing and Gas chromatography-mass spectrometry, respectively. Participants were divided into two groups (more and less active) according to their median step/day count. We compared the microbiota abundance and SCFA concentrations between groups and performed correlation analysis between gut microbiota abundances and study variables. Different microbiota taxa in each PA group and increased SCFAs in feces of less active individuals were found. Changes in step counts were positively or negatively associated with the relative abundance of 19 ASVs, 3 microorganisms at the family level, and 11 microorganisms at the genus level. Furthermore, significant associations were discovered among physical activity, gut microbiota, SCFAs, and sleep parameters. Our findings provide new insights on the relationship between PA, gut microbiota composition, and primary metabolites in older adults with insomnia.

The effects of sleep deprivation on the processing of emotional facial expressions in young adults with and without ADHD.

The ability to recognize emotions from facial expressions is essential to the development of complex social cognition behaviors, and impairments in this ability are associated with poor social competence. This study aimed to examine the effects of sleep deprivation on the processing of emotional facial expressions and nonfacial stimuli in young adults with and without attention-deficit/hyperactivity disorder (ADHD). Thirty-five men (mean age 25.4) with (n = 19) and without (n = 16) ADHD participated in the study. During the five days preceding the experimental session, the participants were required to sleep at least seven hours per night (23:00/24:00-7:00/9:00) and their sleep was monitored via actigraphy. On the morning of the experimental session, the participants completed a 4-stimulus visual oddball task combining facial and nonfacial stimuli, and repeated it after 25 h of sustained wakefulness. At baseline, both study groups had poorer performance in response to facial rather than non-facial target stimuli on all indices of the oddball task, with no differences between the groups. Following sleep deprivation, rates of omission errors, commission errors and reaction time variability increased significantly in the ADHD group but not in the control group. Time and target type (face/non-face) did not have an interactive effect on any indices of the oddball task. Young adults with ADHD are more sensitive to the negative effects of sleep deprivation on attentional processes, including those related to the processing of emotional facial expressions. As poor sleep and excessive daytime sleepiness are common in individuals with ADHD, it is feasible that poor sleep quality and quantity play an important role in cognitive functioning deficits, including the processing of emotional facial expressions that are associated with ADHD.

Maternal sleep related cognitions and child sleep quality: a cross-cultural comparison between the Arab and Jewish societies in Israel.

OBJECTIVES: To examine differences in maternal sleep-related cognitions and to explore the associations between those cognitions and reported child sleep quality in a sample of mothers of young children, from two major cultural groups in Israel: Arab and Jewish. METHOD: Mothers of 497 healthy, typically developing infants and toddler ranging in age from 3-36 months, participated in the study: 253 of the mothers were Arab and 244 were Jewish. Mothers completed the Maternal Cognitions about Infant Sleep Questionnaire, and the Brief Infant Sleep Questionnaire. RESULTS: Cross-cultural differences in maternal sleep-related cognitions were found between Arab and Jewish mothers. Arab mothers were more likely to hold sleep-related cognitions reflecting their difficulty in limiting their nighttime intervention in response to their child's awakenings, compared to Jewish mothers who were more likely to report feelings of anger and higher levels of doubts in their parental competence in response to their child`s nocturnal awakenings. Moderation analyses demonstrated that, only for Arab mothers but not for Jewish mothers, cognitions reflecting difficulty in limiting nighttime intervention, and feelings of anger and doubts were positively associated with poorer perceived child sleep quality. CONCLUSION: The results suggest that the links between maternal cognitions and child sleep are culturally-specific. Moreover, the discrepancies between Arab and Jewish mothers in sleep related cognitions may reflect differences between collectivistic and individualistic cultures. Maternal sleep-related cognitions seem to be an important parental aspect to consider in clinical sleep interventions of infants in the Arab society.

Why Do They Fall? The Impact of Insomnia on Gait of Older Adults: A Case-Control Study.

STUDY OBJECTIVES: To compare gait and cognitive performance conducted separately as a single- (ST) and simultaneously as a dual-task (DT), ie, when a cognitive task was added, among community-dwelling older adults with and without insomnia. METHODS: Participants included: 39 (28 females) community-dwelling older adults with insomnia, 34 (21 females) controls without insomnia. Subject groups were matched for age, gender, and education. Sleep quality was evaluated based on two-week actigraphy. Gait speed and cognition were assessed as ST and DT performance. DT costs (DTCs) were calculated for both tasks. Outcomes were compared via independent samples t-tests or Mann-Whitney U-tests. RESULTS: Older adults with insomnia demonstrated significantly slower gait speed during ST (1 ± 0.29 vs 1.27 ± 0.17 m/s, p<0.001) and DT (0.77 ± 0.26 vs 1.14 ± 0.20 m/s, p<0.001) and fewer correct responses in the cognitive task during ST (21 ± 7 vs 27 ± 11, p=0.009) and DT (19 ± 7 vs 23 ± 9, p=0.015) compared to control group. DTC for the gait task was higher among older adults with insomnia (18.32%, IQR: 9.48-30.93 vs 7.81% IQR: 4.43-14.82, p<0.001). However, no significant difference was observed in DTC for the cognitive task (14.71%, IQR: -0.89-38.84 vs 15%, IQR: -0.89-38.84%, p=0.599). CONCLUSION: Older adults with insomnia have lower gait speed and poorer cognitive performance during ST and DT and an inefficient pattern of task prioritization during walking, compared to counterparts without insomnia. These findings may explain the higher risk of falls among older adults with insomnia. Geriatric professionals should be aware of potential interrelationships between sleep and gait.

Associations between fecal short-chain fatty acids and sleep continuity in older adults with insomnia symptoms.

Insomnia is a disorder characterized by difficulty falling asleep and poor sleep continuity and is associated with increased risks for physical and cognitive decline. Insomnia with short sleep duration is considered the most biologically severe phenotype of the disorder. Evidence suggests that short-chain fatty acids (SCFAs), the main byproducts of fiber fermentation in the gut, may affect sleep via gut-brain communications. This study explores associations between SCFAs and sleep continuity and compares SCFA concentrations in short vs. normal sleep insomnia phenotypes in older adults. Fifty-nine participants with insomnia symptoms (≥ 65 years), completed 2 weeks of objective sleep monitoring (actigraphy), and were divided into short and normal sleep duration phenotypes via cluster analysis. Sleep measures included total sleep time (TST), sleep onset latency (SOL), sleep efficiency (SE), and wake after sleep onset (WASO). Stool samples were collected and fecal SCFA concentrations were determined by gas-chromatography-mass-spectrometry (GCMS). Higher concentrations of acetate, butyrate, and propionate, and total SCFAs, were associated with lower SE and longer SOL after controlling for Body Mass Index (BMI). Concentrations were higher in the short sleep duration phenotype. Age, BMI, TST, and SOL explained 40.7% of the variance in total SCFAs. Findings contribute to understanding pathways along the gut-brain axis and may lead to the use of SCFAs as biomarkers of insomnia phenotypes.

The Impact of Sleep Deprivation on Continuous Performance Task Among Young Men With ADHD.

Objective: To identify the impact of sleep deprivation on functioning of young adults with or without ADHD on a continuous performance attention task. Method: Thirty-four men (M age = 25.38) with (n = 16) or without (n = 18) ADHD completed a continuous performance task before and after 25 hr of sustained wakefulness in a controlled environment. Results: In both groups, sleep deprivation caused a decline in performance on all variables: omission errors, commission errors, reaction time, and reaction time variability. In addition, the ADHD group made more omission and commission errors, and had greater reaction time variability. Conclusion: Sleep deprivation has a detrimental effect on attention functioning among young adults. In addition, although young adults with ADHD generally perform worse on continuous performance tasks than young adults without ADHD, the groups are similarly affected by sleep deprivation.

Maternal perceptions of sleep problems among children and mothers during the coronavirus disease 2019 (COVID-19) pandemic in Israel.

Despite the marked impact of the coronavirus disease 2019 (COVID-19) pandemic on the life of families and its possible negative implications for sleep, little is known about how sleep among parents and children has been impacted by this current crisis. In the present study, we addressed, for the first time, possible consequences of the COVID-19 crisis and home confinement on maternal anxiety, maternal insomnia, and maternal reports of sleep problems among children aged 6-72 months in Israel (N = 264). Our results revealed a high frequency of maternal clinical insomnia during the COVID-19 pandemic: 23% during the pandemic, compared to only 11% before the pandemic (retrospective reports about 1-2 months before the pandemic). About 80% of mothers reported mild-to-high levels of current COVID-19 anxiety. The majority of mothers reported no change in their child's sleep quality, duration, and sleeping arrangement. However, about 30% reported a negative change in child's sleep quality and a decrease in sleep duration, and there were also mothers who reported a positive change. These findings suggest that the changes in sleep patterns during the COVID-19 pandemic are varied and that no unified change for the worse should be expected. Further consideration of changes in sleep within the family context during this ongoing crisis is needed.

Sleep ecology and sleep patterns among infants and toddlers: a cross-cultural comparison between the Arab and Jewish societies in Israel.

OBJECTIVE: The purpose of this study was to examine differences in reported sleep patterns (eg, sleep onset, nocturnal sleep duration, nocturnal wakefulness) and aspects of sleep ecology (eg, sleeping arrangements), in a sample of young children, between two cultural groups in Israel: Arab and Jewish. METHOD: Mothers of 497 healthy, typically developing infants and toddlers, ranging in age from 3 to 36 months, participated in the study: 253 of the mothers were Arab and 244 were Jewish. The mothers were asked to complete the Brief Infant Sleep Questionnaire - a well-validated questionnaire of early childhood sleep patterns. Mothers also completed a demographic questionnaire. RESULTS: Substantial cross-cultural differences in reported sleep patterns were found between Arab and Jewish children. Arab children, compared to Jewish children, had later bedtimes, shorter overall night duration, and longer periods of nocturnal wakefulness. Furthermore, Arab mothers perceived their children's sleep as more problematic than did Jewish mothers. Arab families were more likely to room-share, with higher rates of maternal involvement at bedtime. Sleep onset played an important role in predicting nighttime sleep in Arab children; in the Jewish group, nighttime sleep was linked to parental proximity and assistance at bedtime. CONCLUSION: The findings emphasize the importance of deepening the understanding regarding the role of culture in infants sleep patterns. This will enable health care professionals to attune their interventions to the specific cultural context. Further studies are needed to understand the basis and impacts of these cultural differences.

The Sleepiness Curve of Young Men With and Without Attention-Deficit Hyperactivity Disorder (ADHD).

Objectives: The present study aimed at comparing the sleepiness curve of young men with attention-deficit hyperactivity disorder (ADHD) to that of young men without ADHD before, during, and after a night of sleep deprivation. Participants: Thirty young men (age 18-30) of whom 14 were diagnosed with ADHD combined type (ADHD-C) and 16 without ADHD. Methods: The participants' sleep was monitored for 5 days via actigraphy. Subsequently, the participants were kept continuously awake in a controlled environment for 25 hr (8:00 a.m.-9:00 a.m.). The sleepiness of the participants was assessed every hour by the Karolinska Sleepiness Scale (KSS) in order to obtain the sleepiness curve of both study groups. Results: Actigraphy data demonstrated that the two groups did not differ in their total sleep time, sleep onset latency, or sleep efficiency during the 5 nights preceding the experimental session. However, during the experimental session, the ADHD group demonstrated higher sleepiness scores, particularly following midnight and on the morning following the night of sleep deprivation. Moreover, on the morning following sleep deprivation the proportion of participants reporting extreme levels of sleepiness (KSS > 7) was significantly higher in the ADHD group than in the control group. Conclusions: Young men with ADHD suffer from sleepiness more than their counterparts from the general population, and are particularly vulnerable to the effects of sleep deprivation on sleepiness. As excessive daytime sleepiness negatively affects cognition and increases the risk for motor vehicle crash and other accidents, these findings may have important clinical implications.

The Effect of Sleep Deprivation on Recognition of Ambiguous Emotional Facial Expressions in Individuals With ADHD.

Objective: The present study sought to investigate whether young adults with ADHD have more difficulty recognizing emotional facial expressions compared with young adults without ADHD, and whether such a difference worsens following sleep deprivation. Method: Thirty-one young men (M = 25.6) with (n = 15) or without (n = 16) a diagnosis of ADHD were included in this study. The participants were instructed to sleep 7 hr or more each night for one week, and their sleep quality was monitored via actigraph. Subsequently, the participants were kept awake in a controlled environment for 30 hr. The participants completed a visual emotional morph task twice-at the beginning and at the end of this period. The task included presentation of interpolated face stimuli ranging from neutral facial expressions to fully emotional facial expressions of anger, sadness, or happiness, allowing for assessment of the intensity threshold for recognizing these facial emotional expressions. Results: Actigraphy data demonstrated that while the nightly sleep duration of the participants with ADHD was similar to that of participants without ADHD, their sleep efficiency was poorer. At the onset of the experiment, there were no differences in recognition thresholds between the participants with ADHD and those without ADHD. Following sleep deprivation, however, the ADHD group required clearer facial expressions to recognize the presence of angry, sad, and, to a lesser extent, happy faces. Conclusion: Among young adults with ADHD, sleep deprivation may hinder the processing of emotional facial stimuli.

The Interplay Between Tobacco Dependence and Sleep Quality Among Young Adults.

Objective/Background: Sleep disturbances are considered among the negative consequences of smoking. However, the relationship between sleep quality and smoking among young adults, a population in which the prevalence of smoking is highest, has scarcely been examined. The current study aimed at examining differences in sleep indices, assessed by both subjective and objective (actigraphy) measures, between smokers and nonsmokers, and whether such differences are associated with levels of nicotine dependence. Participants: Eighty-six young (19-28 years old) volunteers, of them 46 nonsmokers (69.6% women) and 40 regular smokers (70.0% women) smoking at least 10 cigarettes a day. Methods: The participants completed the State-Trait Anxiety Inventory, Beck Depression Inventory, Brief Questionnaire on Smoking Urges, the Fagerstrom Test for Nicotine Dependence, and the Pittsburgh Sleep Quality Index. Their sleep was monitored objectively for one week using an actigraph. Results: Smokers' self-reported sleep quality was similar to that of nonsmokers. However, actigraphy data pointed to lower sleep continuity in smokers compared to nonsmokers as reflected by increased wake time after sleep onset (Mean ± SD: 18.56 ± 15.29 vs. 11.21 ± 11.19, p < .01) and decreased sleep efficiency (Mean ± SD: 95.63 ± 3.53 vs. 97.23 ± 2.62, p < .012). Total sleep time and sleep onset latency did not differ between the groups. Notably, severity of nicotine dependence was negatively associated with sleep efficiency (ß = -.32; p < .05). Conclusion: Young adult smokers have lower sleep continuity without necessarily subjectively experiencing their sleep as poor. Nevertheless, their lower sleep continuity is related to their level of nicotine dependence.

Depressive symptoms mediate the relationship between sleep disturbances and type 2 diabetes mellitus.

BACKGROUND: The current study aimed at examining whether individuals diagnosed with type 2 diabetes mellitus (T2DM) have more severe sleep disturbances compared to individuals who are healthy or have prediabetes and whether depressive symptoms mediate the relationship between sleep disturbances and having T2DM. METHODS: T2DM patients (n = 107) were compared to individuals with prediabetes (n = 48) and healthy individuals (n = 154) regarding the severity of depressive symptoms, measured via the Beck Depression Inventory-II (BDI-II), and sleep disturbances, measured via the Mini Sleep Questionnaire (MSQ). Mediation analysis examined whether depressive symptoms mediated the relationship between sleep disturbances and T2DM. RESULTS: Compared to healthy individuals and individuals with prediabetes, T2DM patients had more depressive symptoms and higher levels of insomnia, hypersomnia, and overall more sleep disturbances. The prediabetes group did not differ from the healthy control group on these measures, and these groups were thus combined for further analysis. Sleep disturbances were correlated with severity of depressive symptoms (r =0.43). After controlling for age, gender, and ethnic background, both severity of sleep disturbances (odds ratio [OR]: 1.04; 95% CI: 1.01-1.07, P <.001) and severity of depressive symptoms (OR: 8.54, 95% CI: 3.37-21.69, P <.001) predicted T2DM. Depression symptoms mediated the relationship between sleep disturbances and T2DM, whereas the direct relationship between sleep disturbances and T2DM was nonsignificant. CONCLUSIONS: The findings imply that sleep disturbances may contribute to the development and progression of T2DM by promoting depressive symptoms. Thus, treatments for the emotional distress associated with sleep disturbances may help reduce the risk for T2DM and the progression of the disease.

Depressive Symptoms Mediate the Relationship between Emotional Cutoff and Type 2 Diabetes Mellitus.

BACKGROUND: Differentiation of self is a family systems construct defined as the ability to balance intimacy and autonomy and to separate instinctually driven emotional reactions and thoughtfully considered goal-directed functioning. In theory, low differentiation of self is reflected by four components: a low tendency to take an I-position in relationships (i.e., to own one's thoughts and feelings); emotional cutoff from others; a greater tendency to fuse with others; and a tendency towards emotional reactivity. Low differentiation of self is associated with anxiety and depression, which are risk factors for type 2 diabetes mellitus. The current study examines the relationship between differentiation of self and type 2 diabetes mellitus. METHOD: Individuals with type 2 diabetes mellitus (N = 107) and healthy individuals (N = 145) completed the Differentiation of Self Inventory-Revised (DSI-R), the State-Trait Anxiety Inventory (STAI), and the Beck Depression Inventory (BDI-II). RESULTS: Compared with healthy individuals, participants with type 2 diabetes had more severe depressive symptoms, higher levels of emotional cutoff, and a lower tendency to take an I-position, but had similar levels of trait anxiety, emotional reactivity, and fusion with others (factor analysis revealed these factors were not separable in the current sample and thus were merged into a single construct). Importantly, the severity of depressive symptoms mediated the relationship between emotional cutoff and being in the type 2 diabetes study group rather than the healthy group. CONCLUSION: These findings suggest a new perspective on the role of psychological patterns in type 2 diabetes mellitus development and progression.

The Relationship Between Tobacco Smoking, Cortisol Secretion, and Sleep Continuity.

Background: Existing theories hold that chronic tobacco smoking leads to the development of adverse psychological symptoms, thus producing a compulsive urge to smoke in order to alleviate these sensations. Sleep disturbances are often considered among the negative consequences of chronic smoking. Objectives: The current study aimed at examining whether dysregulation of the hypothalamic-pituitary-adrenocortical (HPA) axis may be involved in this disruption of sleep quality among smokers. Methods: Smokers and non-smokers provided saliva samples following awakening for assessment of cortisol concentrations as a measure of HPA activity. Subsequently the participants completed the State-Trait Anxiety Inventory, Brief Questionnaire on Smoking Urges, the Fagerstrom Test for Nicotine Dependence, and the Pittsburgh Sleep Quality Index. Next, their sleep was monitored objectively for one week using an actigraph. Results: While smokers' self-reported sleep quality was similar to that of non-smokers, their sleep recording data pointed to diminished sleep continuity (increased wake time after sleep onset; WASO), while total sleep time and sleep onset latency were similar to that of non-smokers. Cortisol secretion was higher among smokers. However, among smokers only, cortisol was negatively correlated with WASO, suggesting that the direct enhancing effect of smoking on WASO is somewhat balanced by an indirect process related to higher cortisol levels. Possible interpretations for this inconsistent mediation are discussed. Conclusions/Importance: Smoking is associated with reduced sleep continuity and the relationship between smoking and sleep continuity may involve the HPA axis.