Associations between post-traumatic stress symptoms and sleep/circadian parameters: Exploring the effect of chronotype as a moderator variable

The present study aimed at evaluating how post-traumatic stress symptoms (PTSS) are associated with rest-activity circadian and sleep-related parameters, assessed both subjectively (via questionnaires) and objectively (via actigraphy). Specifically, we explored whether chronotype could moderate the association between sleep/circadian parameters and PTSS. Participants (n = 120 adults; mean age 35.6 ± 14; 48 male) were assessed through the Trauma and Loss Spectrum Self Report (TALS-SR) for lifetime PTSS, the reduced version of the Morningness-Eveningness Questionnaire (rMEQ) for chronotype, the Pittsburgh Sleep Quality Index (PSQI) for self-reported sleep quality, and wrist actigraphy for sleep and circadian parameters. Eveningness, poor self-reported sleep quality, lower sleep efficiency (SE), lower interdaily stability (IS), and higher intradaily variability (IV) were correlated with higher TALS-SR scores. Regression analyses showed that IV, SE, and PSQI remained associated with TALS symptomatic domains after adjusting for potentially confounding factors (age and gender). Moderation analysis showed that only the PSQI remained significantly associated with TALS symptomatic domains; however, the interaction with chronotype was not significant. Targeting self-reported sleep disturbances and rest-activity rhythms fragmentation could mitigate PTSS. Although the effect of chronotype as a moderator of the associations between sleep/circadian parameters and PTSS was not significant, eveningness was associated with higher TALS scores, thus confirming the vulnerability of evening types to worse stress reactions.

Poor sleep quality and unhealthy lifestyle during the lockdown: an Italian study

Background

The lockdown measure implemented to face the 2019 Coronavirus Disease (COVID-19) first wave deeply modified the lifestyle of the Italian population. Despite its efficacy in limiting the number of infections, forced home confinement was paralleled by sleep/wake cycle disruptions, psychological distress and maladaptive coping strategies (i.e., unhealthy behaviours, such as tobacco and alcohol consumption). Under these unprecedented stress conditions, we explored a possible association between poor sleep quality and increased likelihood of engaging in an unhealthy lifestyle.

Methods

A cross-sectional study was conducted by disseminating an online survey via social networks and e-mail. We collected information on demographics, COVID-19-related data, sleep quality, chronotype, circadian misalignment, and lifestyle before and during the lockdown (i.e., consumption of cigarettes, alcoholic beverages, coffee, hypnotics, comfort food and fresh food; practice of physical activity). A global healthiness score was computed to assess participants’ modifications in lifestyle since the beginning of the lockdown.

Results

1297 respondents were included in the study: 414 (31.9%) from Northern Italy, 723 (55.8%) from Central Italy, 160 (12.3%) from Southern Italy. The following variables were found to be significant predictors of the adoption of an unhealthy lifestyle since the beginning of the lockdown: poor sleep quality, high BMI and considering the measures adopted by the government to fight the pandemic as excessive. Living in Northern Italy, instead, was associated with healthier habits compared to living in Central Italy.

Conclusions

Poor sleepers may represent the share of the general population who paid the highest price for social isolation. Further investigations are required to explore the role of sleep quality assessment in the identification of individuals vulnerable to unhealthy behaviours under stressful conditions.

Sleep quality mediates the effect of chronotype on resilience in the time of COVID-19

This study aimed to explore the relationship between chronotype and resilience, sleep quality, and post-traumatic stress reactions during the first COVID-19 lockdown in Italy. An online survey was distributed through social networks during forced home confinement, collecting data from1298 participants of 19 different Italian regions. Chronotype was evaluated using the reduced version of the Morningness/Eveningness Questionnaire (rMEQ); sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI); resilience levels were measured by the 10-item version of the Connor-Davidson Resilience Scale (CD-RISC10); post-traumatic stress reactions were assessed by the 6-item version of the Impact of Event Scale (IES6). Resilience and sleep quality were significantly lower in the evening compared to non-evening types, as well as in females as compared to males. Moreover, resilience was negatively correlated with post-traumatic stress reactions and positively correlated with sleep quality. A negative correlation was also reported between sleep quality and post-traumatic stress reactions. Sleep quality was identified as a possible mediator between chronotype and resilience, and between resilience and post-traumatic stress reactions, after controlling for age and sex. These findings provide new insights into the role of chronotype in adapting to continuous stressful situations. Sleep quality seems to mediate the causal path between the antecedents of resilience and the development of trauma. Further research is needed to explore the suitability of primary interventions based on chronobiology and sleep hygiene to mitigate the impact of pandemic-related home confinement measures on mental health among the general population.

Heart rate variability at bedtime predicts subsequent sleep features

Getting enough sleep during the night is important for preventing adverse short- and long-term health outcomes. The sympathetic-parasympathetic autonomic balance, characteristics of the pre-bed time resting period, correlates with sleep efficiency. We investigated in healthy subjects whether Low/High Frequencies (LF/HF) and other Heart Rate Variability (HRV) metrics, extracted in the period immediately before sleep onset, are able to predict quality/architecture sleep parameters in the sample group and in the Evening-Intermediate- chronotype subgroups. Linear correlations were found between HRV metrics and the investigated quality/architecture sleep parameters. The possibility to predict sleep parameters from the HRV metrics while falling asleep might pave the way to behavioral interventions during the bedtime period to increase the quality of sleep.

The Complexity of Dreams: a Multiscale Entropy Study on Cardiovascular Variability Series

Uncovering the physiological correlates of dreams is one of the most ambitious aim of multidisciplinary neuroscientific research. Here we investigated Autonomic Nervous System (ANS) dynamics associated with a dream recall, with a particular focus on the complexity assessment on cardiovascular control. We recorded electrocardiogram and arterial blood pressure signals from eight healthy subjects during rapid-eye-movement sleep before awakenings. Recordings were then split into two groups: the ones with a dream experience, and the ones without recall of dream experiences. The randomness of cardiovascular variability series was assessed through Sample Entropy metrics, which did not show any statistical difference between groups. On the other hand, a multiscale complexity analysis based on Distribution Entropy and Fuzzy Entropy revealed that a higher cardiovascular complexity is associated with a dreaming experience.

Vascular Function Is Improved After an Environmental Enrichment Program

Environmental enrichment may slow cognitive decay possibly acting through an improvement in vascular function. Aim of the study was to assess the effects of a 7-month cognitive, social, and physical training program on cognitive and vascular function in patients with mild cognitive impairment. In a single-center, randomized, parallel-group study, 113 patients (age, 65–89 years) were randomized to multidomain training (n=55) or usual care (n=58). All participants underwent neuropsychological tests and vascular evaluation, including brachial artery flow-mediated dilation, carotid–femoral pulse wave velocity, carotid distensibility, and assessment of circulating hematopoietic CD34+ and endothelial progenitor cells. At study entry, an age-matched control group (n=45) was also studied. Compared with controls, patients had at study entry a reduced flow-mediated dilation (2.97±2.14% versus 3.73±2.06%; P =0.03) and hyperemic stimulus (shear rate area under the curve, 19.1±15.7 versus 25.7±15.1×10 −3 ; P =0.009); only the latter remained significant after adjustment for confounders ( P =0.03). Training improved Alzheimer disease assessment scale cognitive (training, 14.0±4.8 to 13.1±5.5; nontraining, 12.1±3.9 to 13.2±4.8; P for interaction visit×training=0.02), flow-mediated dilation (2.82±2.19% to 3.40±1.81%, 3.05±2.08% to 2.24±1.59%; P =0.006; P =0.023 after adjustment for diameter and shear rate area under the curve), and circulating hematopoietic CD34 + cells and prevented the decline in carotid distensibility (18.4±5.3 to 20.0±6.6, 23.9±11.0 to 19.5±7.1 Pa −1 ; P =0.005). The only clinical predictor of improvement of cognitive function after training was established hypertension. There was no correlation between changes in measures of cognitive and vascular function. In conclusion, a multidomain training program slows cognitive decline, especially in hypertensive individuals. This effect is accompanied by improved systemic endothelial function, mobilization of progenitor CD34 + cells, and preserved carotid distensibility.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT01725178.

Insomnia symptoms, perceived stress and coping strategies in patients with systemic lupus erythematosus

Objective

The aim of this study is to evaluate perceived stress and coping strategies in individuals with systemic lupus erythematosus (SLE) according to the presence of insomnia symptoms, using a set of variables that include anxiety and depressive symptoms evaluation.

Methods

Ninety SLE women were evaluated in a cross-sectional study using the Perceived Stress Scale (PSS), Brief COPE, Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Beck Depression Inventory (BDI) and Self-rating Anxiety Scale (SAS).

Results

Individuals with insomnia symptoms ( n = 57, 66%) presented higher PSS ( p < 0.001), PSQI ( p < 0.0001), BDI, ( p < 0.0001) scores and showed less-effective coping strategies such as the use of behavioral disengagement ( p = 0.04), self-blame ( p = 0.02) and emotional-focused coping ( p = 0.001). In a multi-regression model ISI was the independent determinant of high PSS and of behavioral disengagement; PSQI was the only determinant of self-blame ( p = 0.02) and emotional-focused coping.

Conclusions

SLE individuals with insomnia symptoms show high levels of perceived stress and more frequent use of disengaging and emotional-focused coping strategies. This body of evidence suggests that individuals with SLE and comorbid insomnia symptoms may therefore require additional interventions for insomnia.