The Attend Study: A Retrospective Observational Study of Emergency Department Attendances During the Early Stages of the COVID-19 Pandemic.

INTRODUCTION: The coronavirus disease-19 (COVID-19) pandemic was associated with a large reduction in the number of attendances at emergency departments (EDs) in March 2020 in the United Kingdom (UK). We sought to identify which patient groups attended EDs least. METHODS: Single-centre before and after study. We used routine administrative data from March 2020 and compared this to a composite control of March 2019 and February 2020.  Results: Mean daily attendance fell by 30% from 342 patients per day in the composite control months to 242 patients per day in March 2020. Reductions in attendance were seen in almost all patient groups but were greatest in patients with injuries, those referred by another clinician, those arriving at the weekend, and in patients who received no investigations. Multivariate analysis revealed that the proportion of patients who were admitted to hospital fell, despite the patients being sicker, older, needing more investigations, and more likely to arrive by ambulance. DISCUSSION: The reduction in ED attendances seen in the early phases of the UK pandemic occurred in all patient groups, but was greatest in the lower acuity patients. Reasons for this are complex and likely to be multifactorial.

Preparing for Mars: human sleep and performance during a 13 month stay in Antarctica.

Study Objectives: Manned spaceflights from Earth to Mars will likely become reality within the next decades. Humans will be exposed to prolonged isolation, confinement, and altered photoperiods under artificial atmospheric conditions, with potential adverse effects on sleep and performance. On Earth, polar environments serve as space analogs to study human adaptation; yet, few studies include polysomnography due to operational constraints. Methods: Polysomnography, self-reported sleepiness and fatigue, and psychomotor performance were measured every 6 weeks in 13 males ("Hivernauts") during a 13 month winter-over campaign at Concordia (Antarctica). Stability and robustness of interindividual differences were examined by means of intraclass correlations. Results: Hivernauts present with high-altitude periodic breathing, increased sleep onset latencies, and reduced psychomotor speed. Except for obstructive apneas, all sleep, sleepiness, and psychomotor performance variables remain stable over time. Individual differences in respiratory variables show the highest degree of stability and robustness, followed by fatigue and situational sleepiness, sleep fragmentation, and psychomotor speed, suggesting moderate to substantial trait-like characteristics for these variables. Phase delays are suspected in Hivernauts, both in individuals with imposed and self-selected bedtimes. A significant decline in psychomotor speed over time is observed in the latter group. Conclusions: Space analog conditions such as isolated confinement, extreme photoperiods, and altered atmospheric conditions affect human sleep and performance. However, individual responses to these extreme environmental challenges show large differences and remain relatively stable under prolonged exposure. Ad hoc polysomnographic, including respiratory function monitoring is therefore recommended for selecting eligible candidates for extraterrestrial sojourns.

Exercise during Short-Term and Long-Term Continuous Exposure to Hypoxia Exacerbates Sleep-Related Periodic Breathing.

STUDY OBJECTIVES: Exposure to hypoxia elevates chemosensitivity, which can lead to periodic breathing. Exercise impacts gas exchange, altering chemosensitivity; however, interactions between sleep, exercise and chronic hypoxic exposure have not been examined. This study investigated whether exercise exacerbates sleep-related periodic breathing in hypoxia. METHODS: Two experimental phases. Short-Term Phase: a laboratory controlled, group-design study in which 16 active, healthy men (age: 25 ± 3 y, height: 1.79 ± 0.06 m, mass: 74 ± 8 kg) were confined to a normobaric hypoxic environment (FIO2 = 0.139 ± 0.003, 4,000 m) for 10 days, after random assignment to a sedentary (control, CON) or cycle-exercise group (EX). Long-Term Phase: conducted at the Concordia Antarctic Research Station (3,800 m equivalent at the Equator) where 14 men (age: 36 ± 9 y, height: 1.77 ± 0.09 m, mass: 75 ± 10 kg) lived for 12-14 months, continuously confined. Participants were stratified post hoc based on self-reported physical activity levels. We quantified apnea-hypopnea index (AHI) and physical activity variables. RESULTS: Short-Term Phase: mean AHI scores were significantly elevated in the EX group compared to CON (Night1 = CON: 39 ± 51, EX: 91 ± 59; Night10 = CON: 32 ± 32, EX: 92 ± 48; P = 0.046). Long-Term Phase: AHI was correlated to mean exercise time (R(2) = 0.4857; P = 0.008) and the coefficient of variation in night oxyhemoglobin saturation (SpO2; R(2) = 0.3062; P = 0.049). CONCLUSIONS: Data indicate that exercise (physical activity) per se affects night SpO2 concentrations and AHI after a minimum of two bouts of moderate-intensity hypoxic exercise, while habitual physical activity in hypobaric hypoxic confinement affects breathing during sleep, up to 13+ months' duration.

Exercise in isolation--a countermeasure for electrocortical, mental and cognitive impairments.

INTRODUCTION: Mental impairments, including deterioration of mood and cognitive performance, are known to occur during isolation and space missions, but have been insufficiently investigated. Appropriate countermeasures are required, such as exercise, which is known to prevent mood disorders for prolonged space and isolation missions. Based on the interaction of brain activity, mood and cognitive performance, this study aims to investigate the effect of long-term isolation and confinement and the long-term effect of exercise on these parameters. METHODS: Eight male volunteers were isolated and confined for about eight month during the winter period at the Antarctic Concordia Station. Every six weeks electroencephalographic measurements were recorded under rest conditions, and cognitive tests and a mood questionnaire were executed. Based individual training logs, subjects were afterwards separated into an active (> 2500 arbitrary training units/interval) or inactive (< 2500 arbitrary training units/interval) group. RESULTS: A long-term effect of exercise was observed for brain activity and mood. Regularly active people showed a decreased brain activity (alpha and beta) in the course of isolation, and steady mood. Inactive people instead first increased and than remained at high brain activity accompanied with a deterioration of mood. No effect of exercise and isolation was found for cognitive performance. CONCLUSION: The findings point out the positive effect of regularly performed voluntary exercise, supporting subjective mental well-being of long-term isolated people. The choice to be regularly active seems to support mental health, which is not only of interest for future isolation and space missions.

Altitude and seasonality impact on sleep in Antarctica.

BACKGROUND: This study investigates the effects of seasonality and altitude on sleep in extreme Antarctic conditions. METHODS: During summer and winter periods, 24 h of actimetric recordings were obtained at two different research stations, Dumont d'Urville (sea level altitude) and Concordia (corrected altitude 12,467 ft or 3800 m). RESULTS: During daytime, there were no altitude- or season-related differences in time spent at work, energy expenditure, or number of walking steps. During the nighttime however, total sleep time was longer (m = 427.4; SD = 42.4), sleep efficiency higher (m = 90; SD = 4.8), and wake after sleep onset shorter (m = 42.2; SD = 28.7) at sea level. Additionally, sleep fragmentation episodes and energy expenditure were higher during summer than winter periods. DISCUSSION: Our results show that dramatic variations in light exposure are not the only main factor affecting sleep quality in Antarctica, as altitude also markedly impacted sleep in these conditions. The effect of altitude-induced hypoxia should be taken into account in future investigations of sleep in extreme environments.