SCREEN TIME AND SLEEP IN YOUNG ADOLESCENTS BEFORE AND ACROSS THE FIRST YEAR OF THE COVID-19 PANDEMIC

Introduction: The COVID-19 pandemic has been associated with profound biopsychosocial changes for children, potentially affecting their health and wellbeing. Among these changes are altered sleep patterns and screen time use, however, no work has examined interactions between these two behaviors in the context of the pandemic. Here, we used longitudinal data from the Adolescent Brain Cognitive Development (ABCD) Study® to investigate changes in both sleep and screen time, and their relationship, from before and across the first year of the COVID-19 pandemic in young adolescents. Methods: More than 5000 adolescents (11-14 years;48% girls) completed digital surveys about their sleep and daily screen time use before the pandemic and across six timepoints during 2020- 2021, as part of the ongoing ABCD Study®. Random intercept linear mixed effect models (LMMs) were used to examine longitudinal associations between bedtime, wake-up time, and daily screen time use (social media, gaming), considering age, sex, and school effects. Results: Adolescents' wake up time was delayed (R2 = 0.51;~1.5 hour) during May-August 2020 relative to the pre-pandemic assessment (p<0.01), which was partially related to the summer break (p<0.01), before advancing to earlier times in October 2020. Bedtimes also delayed at all pandemic assessments (R2=0.62;~1 hour), even after starting the new school year (p<0.01), particularly in older adolescents (p<0.01) and girls (p<0.01). Recreational screen time was dramatically higher across the first year of the pandemic, relative to pre-pandemic (p<0.01;~45min social media, ~20min video gaming). More time spent with screen related activities was associated with later bedtimes and wake up times (p<0.01), across the pandemic, with effects being evident in male and female adolescents. Conclusion: Our findings show profound changes in sleep timing and screen time use across the pandemic in young adolescents, and critically, that excessive screen time negatively impacts sleep. As adolescents increasingly turn to more screen usage, these data highlight the need to promote their balanced and informed use of social media platforms, video games, and other digital technology to ensure adequate opportunity to sleep and maintain other healthy behaviors during this critical period of developmental change.

Pericardial constriction-like echocardiographic findings in elite athletes following mild covid-19 infection: A propensity score-matched analysis

Introduction: The cardiovascular effects of COVID-19 in elite athletes is still a matter of intense scientific debate. Hypothesis: We sought to perform a comprehensive echocardiographic characterization of postCOVID athletes by comparing them to a non-COVID athlete cohort. Methods: 107 elite athletes with COVID-19 were prospectively enrolled (P-CA;23±6 years, 23% female) 107 healthy athletes were selected as a control group using propensity score matching (NCA). All athletes underwent 2D and 3D echocardiography. Left (LV) and right ventricular (RV) enddiastolic volumes (EDVi) and ejection fractions (EF) were quantified. To characterize LV longitudinal deformation, 2D global longitudinal strain (GLS) and the ratio of free wall versus septal longitudinal strain (FWLS/SLS) were also measured. To describe septal flattening (SF-frequently seen in PCA), LV eccentricity index (EI) was calculated.Results: P-CA and N-CA athletes had comparable LV and RVEDVi (P-CA vs N-CA;77±12 vs. 78±13mL/m2;79±16 vs 80±14mL/m2). P-CA had significantly higher LVEF (58±4 vs 56±4%, p<0.001), while LVGLS values did not differ between P-CA and N-CA (-19.0±1.9 vs -18.8±2.2%). EI was significantly higher in P-CA (1.13±0.16 vs 1.01±0.05, p<0.001), which was attributable to a distinct subgroup of P-CA with a prominent SF (n=35, 33%), further provoked by inspiration. In this subgroup, the EI was markedly higher compared to the rest of the P-CA (1.29±0.15 vs 1.04±0.08, p<0.001), LVEDVi was also significantly higher (80±14 vs 75±11 mL/m2, p<0.001), while RVEDVi did not differ (82±16 vs 78±15mL/m2). Moreover, the FWLS/SLS ratio was significantly lower in the SF subgroup (91.7±8.6 vs 97.3±8.2, p<0.01). P-CA with SF experienced symptoms less frequently (1.4±1.3 vs. 2.1±1.5 symptom during the infection, p=0.01). Conclusions: COVID-19 infection might be frequently associated with a constriction-like physiology in elite athletes.

Frequent constriction-like echocardiographic findings in elite athletes following mild COVID-19: In the grasp of SARS-CoV-2?

The COVID-19 pandemic had a major impact on the sports community as well. Despite the vast majority of athletes experiencing mild symptoms, potential cardiac involvement and complications have to be explored to support a safe return to play. Accordingly, we were aimed at a comprehensive echocardiographic characterization of post-COVID athletes (P-CA) by comparing them to a propensity-matched healthy, non-COVID athlete (NCA) cohort. One hundred and seven elite athletes with COVID-19 were prospectively enrolled after an appropriate quarantine period and formed the P-CA group (23±6 years, 23% female). From our retrospective database comprising 425 elite athletes, 107 age-, gender-, body surface area-, and weekly training hours-matched subjects were selected as a reference group using propensity score matching (N-CA group). All athletes underwent a comprehensive clinical investigation protocol comprising 2D and 3D echocardiography. Left (LV) and right ventricular (RV) end-diastolic volumes (EDVi) and ejection fractions (EF) were quantified using dedicated softwares. To characterize LV longitudinal deformation, 2D global longitudinal strain (GLS) and the ratio of free wall versus septal longitudinal strain (FWLS/SLS) were also calculated. In order to describe septal flattening (SF-frequently seen in P-CA), LV eccentricity index (EI) was measured. P-CA and N-CA athletes had comparable LV and RV EDVi (P-CA vs NCA;77±12 vs 78±13mL/m2;79±16 vs 80±14mL/m2, respectively). P-CA group had significantly higher LV EF (58±4 vs 56±4%, p<0.001) and GLS (-18.2±1.8 vs -17.6±2.2%, p<0.05). Eccentricity index was significantly lower in P-CA (0.89±0.10 vs 0.99±0.04, p<0.001), which was attributable to a distinct subgroup of P-CA athletes with a prominent SF (n=34, 32%), further provoked by inspiration. In this subgroup, the eccentricity index was markedly lower compared to the rest of the P-CA group (0.79±0.07 vs 0.95±0.07, p<0.001). In the SF subgroup, LV EDVi was significantly higher (80±14 vs 75±11 mL/m2, p<0.001), while RV EDVi did not differ (82±16 vs 78±15mL/m2). Moreover, the FWLS/SLS ratio was significantly lower in the SF subgroup (0.92±0.09 vs 0.97±0.08, p<0.01). Interestingly, P-CA athletes with SF experienced fatigue (17 vs 34%, p<0.05) or chest pain (0 vs 15%, p=) less frequently during the course of the infection;however, the presence of a mild pericardial effusion was more common (41 vs 12%, p<0.01). Elite athletes following COVID-19 showed distinct morphological and functional cardiac changes compared to a propensity score-matched control athlete group. These results are mainly driven by a subgroup, which presented with some echocardiographic features characteristic of constrictive pericarditis (septal flattening, lower FWLS/SLS ratio, pericardial effusion). Follow-up of athletes and further, higher case number studies are warranted to determine the clinical significance and potential effects on exercise capacity of these findings.

Cardiopulmonary examinations of athletes returning to high-intensity sport activity following SARS-CoV-2 infection

During the pandemic, several studies were carried out on the short-term effects of acute SARS-CoV-2 infection in athletes. As some cases of young athletes with serious complications like myocarditis or thromboembolism and even sudden death were reported, strict recommendations for return to sport were published. However, we have less data about athletes who have already returned to high-intensity trainings after a SARS-CoV-2 infection. Athletes underwent cardiology screening (personal history, physical examination, 12-lead resting ECG, laboratory tests with necroenzyme levels and echocardiography) 2 to 3 weeks after suffering a SARS-CoV-2 infection. In case of negative results, they were advised to start low intensity trainings and increase training intensity regularly until achieving maximal intensity a minimum of 3 weeks later. A second step of cardiology screening was also carried out after returning to maximal intensity trainings. The above mentioned screening protocol was repeated and was completed with vita maxima cardiopulmonary exercise testing (CPET) on running treadmill. If the previous examinations indicated, 24h Holter ECG recording, 24h ambulatory blood pressure monitoring or cardiac MR imaging were also carried out. Data are presented as mean±SD. Two-step screening after SARS-CoV-2 infection was carried out in 111 athletes (male:74, age:22.4±7.4y, elite athlete:90%, training hours:14.8±5.8 h/w, ice hockey players:31.5%, water polo players:22.5%, wrestlers:18.9%, basketball players:18.0%). Second screenings were carried out 94.5±31.5 days after the first symptoms of the infection. A 5% of the athletes was still complaining of tiredness and decreased exercise capacity. Resting heart rate was 70.3±13.0 b.p.m., During CPET examinations, athletes achieved a maximal heart rate of 187.3±11.6 b.p.m., maximal relative aerobic capacity of 49.2±5.5 ml/kg/min, and maximal ventilation of 138.6±31.2 l/min. The athletes reached their anaerobic threshold at 87.8±6.3% of their maximal aerobic capacity, with a heart rate of 93.3±3.7% of their maximal values. Heart rate recovery was 29.9±9.2/min. During the CPET examinations, short supraventricular runs, repetititve ventricular premature beats + ventricular quadrigeminy and inferior ST depression were found in 1-1 cases. Slightly higher pulmonary pressure was measured on the echocardiography in 4 cases. Hypertension requiring drug treatment was found in 5.4% of the cases. Laboratory examinations revealed decreased vitamin D3 levels in 26 cases, decreased iron storage levels in 18 athletes. No SARS-CoV-2 infection related CMR changes were revealed in our athlete population. Three months after SARS-CoV-2 infection, most of the athletes examined had satisfactory fitness levels. However, some cases of decreased exercise capacity, decreased vitamin D3 or iron storage levels, arrhythmias, hypertension and elevated pulmonary pressure requiring further examinations, treatment or follow-up were revealed.

Poor sleep as a predictor of COVID-19 related stress, fear and sadness in young adolescents: A longitudinal study

Introduction: Adolescence is a transitional life-stage accompanied by large biopsychosocial changes and greater psychophysiological vulnerability. Global events like the COVID-19 pandemic may increase vulnerability to depression and anxiety in this population. Poor sleep is often associated with depression, and both sleep and mood have been shown to be strongly impacted by the COVID-19 pandemic, with most studies focusing on adults. The current study investigates psychological distress in young adolescents during the pandemic, and specifically, whether poor sleep before the pandemic predicts psychological distress. Methods: Self-report data were analyzed from 3099 adolescents (9-10 years at baseline) in the population-based, demographically diverse, Adolescent Brain Cognitive Development (ABCD) study across three pre-pandemic annual visits and 3 monthly time points during the COVID-19 pandemic (ages 11-13 years). At each assessment, children and their guardians completed questionnaires including those about sleep, environment, and psychological wellbeing. Gradient Boosted Tree machine learning algorithms were used to identify the strongest predictors of pandemic-related psychological distress in individuals. We trained models using pre-pandemic sleep measures along with demographics, economic, and social measures during the pandemic. We evaluated the performance of the models using area under curve (AUC) metrics and interpreted the models by using the recently proposed SHapley Additive exPlanations methodology. Results: Pandemic-related perceived stress, fear and sadness were accurately detected with our classifiers (AUC = 0.83 for perceived stress, AUC = 0.73 for fear, AUC = 0.79 for sadness). Across all models, shorter sleep duration, prolonged sleep onset latency, and longer time between waking and getting out of bed predicted greater distress. Moreover, female sex, and pandemic-related factors, including greater family conflict, fewer economic resources, and more screen time contributed to prediction performance in all three models. Conclusion: Findings highlight the importance of addressing sleep problems and ensuring sufficient sleep duration in children to protect against the psychological impact of major life events, including the COVID-19 pandemic. Considering the long-lasting effects of sleep, it would be crucial to improve sleep health by targeted prevention, intervention and increased awareness among adolescents.