Circadian disturbances, sleep difficulties and the COVID-19 pandemic

Abstract

The COVID-19 pandemic has imposed extraordinary and unpredictable changes on our lifestyle for an unknown duration. Consequently, core aspects of wellbeing including behavior, emotion, cognition, and social interactions are negatively affected. Sleep and circadian rhythms, with an extensive impact on physiology, behavior, emotion, and cognition are inevitably affected too. We provided an updated overview of the impact of the COVID-19 pandemic on circadian rhythms and sleep based on the results of published studies ( n =48) in three sections. First, we focus on circadian misalignment due to the pandemic in the general population (including shift workers, health staff, students) and COVID-19 patients and summarize the most critically contributing factors to circadian misalignment. Next, we address sleep difficulties and poor sleep quality during the pandemic, their contributing factors, rate and prevalence, and their effects on both the general population and COVID-19 patients. Finally, we summarize the currently applied/recommended interventions for aligning circadian rhythms and improving sleep quality in both, the general population, and COVID-19 patients during the pandemic situation. Briefly, circadian misalignment and sleep difficulties are common consequences of the pandemic in the general population (with elderly, students, children, health and night-work shifters as risk groups) and COVID-19 patients. Home confinement and its physiological, circadian, and psychological derivates are central to these difficulties. Symptoms severity, treatment progress, recovery duration, and even diagnosis of COVID-19 patients are considerably affected by circadian and sleep difficulties. Behavioral interventions for normalizing the factors that contribute to circadian and sleep difficulties are helpful and recommended.

Pandemic and student mental health: A cross-sectional and longitudinal analysis of mental health symptoms amongst university students and young adults after the first cycle of lockdown in the UK

“…These findings add to the existing literature on the mental health risk associated with non-male gender and financial pressure (25) (26) (27). They are also consistent with the view that circadian misalignment and sleep difficulties are common consequences of the pandemic that negatively affected core aspects of wellbeing and contributed to the aggravation of pre-existing psychological problems (28).…”

“…Each question is weighted differently depending on the severity of the risk examined by the item: for example, the item asking participants 'how often have you failed to do what was normally expected of you because of your use of (first drug, second drug, etc)' is weighted more heavily than the question 'In the past three months, how often have you used the substances you mentioned (first drug, second drug, etc)?'. The average total score for all substances is used to evaluate risk: low risk (0-3), moderate risk (4-26) and high risk (27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39).…”

Circadian misalignment is associated with Covid-19 infection

“…Social jetlag is a chronic misalignment between internal circadian clocks and external time (social time). Taken together, these results support the hypothesis that circadian misalignment could promote SARS-CoV-2 infection ( 6 , 7 , 8 ). Nevertheless, usual circadian misalignment as a risk factor for contracting Covid-19 has up to now been poorly studied.…”

Sleep-dependent upscaled excitability, saturated neuroplasticity, and modulated cognition in the human brain

“…While we found decreased cortical facilitation and lower neuroplasticity induction (same for both LTP and LTD) at the circadian nonpreferred time in that study (Salehinejad et al, 2021b), here we observed upscaled cortical excitability and a functionally different pattern of neuroplasticity alteration (i.e., diminished LTP-like plasticity induction and conversion of LTD-to LTP-like plasticity). Second, the results of the present study underscore the importance of sufficient sleep for adaptive and efficient performance (e.g., in working or educational environments) (Salehinejad et al, 2021a) which is specifically important in individuals with demanding jobs (e.g., night shift workers). Furthermore, the relevance of sleep for brain plasticity and optimal cortical excitability argues for the role of sufficient sleep in preventing disorders that are associated with cognitive and/or plasticity deficits, such as Alzheimer's disease (Ju et al, 2014) and major depression (Wolf et al, 2016) that constitute a growing public health concern.…”