ABSTRACT
Intensive care unit healthcare workers (ICU HCW) are at risk of mental health disorders during emerging disease outbreaks. Numerous cross-sectional studies have reported psychological distress, anxiety, and depression amongst ICU HCW during the COVID-19 pandemic. However, few studies have followed HCW longitudinally, and none of these have examined the association between COVID-19 workload and mental health. We conducted a longitudinal cohort study of 309 Canadian ICU HCW from April 2020 to August 2020, during the 1st wave of the COVID-19 pandemic. Psychological distress was assessed using the General Health Questionnaire 12-item scale (GHQ-12) at 3 timepoints: during the acceleration phase of the 1st wave (T1), the deceleration phase of the 1st wave (T2), and after the 1st wave had passed (T3). Clinically relevant psychological distress, defined as a GHQ-12 score ≥ 3, was identified in 64.7% of participants at T1, 41.0% at T2, and 34.6% at T3. Psychological distress was not associated with COVID-19 workload at T1. At T2, psychological distress was associated with the number of COVID-19 patients in the ICU (odds ratio [OR]: 1.06, 95% confidence interval [CI]: 1.00, 1.13) while at T3, when COVID-19 patient numbers were low, it was associated with the number of weekly hospital shifts with COVID-19 exposure (OR: 1.33, 95% CI: 1.09, 1.64). When analyzed longitudinally in a mixed effects model, pandemic timepoint was a stronger predictor of psychological distress (OR: 0.24, 95% CI: 0.15, 0.40 for T2 and OR: 0.16, 95% CI: 0.09, 0.27 for T3) than COVID-19 workload. Participants who showed persistent psychological distress at T3 were compared with those who showed recovery at T3. Persistent psychological distress was associated with a higher number of weekly shifts with COVID-19 exposure (OR: 1.97, 95% CI:1.33, 3.09) but not with a higher number of COVID-19 patients in the ICU (OR: 0.86, 95% CI: 0.76, 0.95). In summary, clinically relevant psychological distress was observed in a majority of ICU HCW during the acceleration phase of the 1st wave of the COVID-19 pandemic but decreased rapidly as the 1st wave progressed. Persistent psychological distress was associated with working more weekly shifts with COVID-19 exposure but not with higher numbers of COVID-19 patients in the ICU. In future emerging disease outbreaks, minimizing shifts with direct disease exposure may help alleviate symptoms for individuals with persistent psychological distress.
Subject(s)
COVID-19 , Psychological Distress , Humans , Longitudinal Studies , Pandemics , Cross-Sectional Studies , Workload , COVID-19/epidemiology , Canada/epidemiology , Cohort Studies , Health Personnel , Intensive Care Units , Depression/epidemiologyABSTRACT
OBJECTIVES: DNA methylation can be used to determine an individual's biological age, as opposed to chronological age, an indicator of underlying health status. This study aimed to assess epigenetic age in critically ill patients with and without sepsis to determine if higher epigenetic age is associated with admission diagnosis or mortality. DESIGN: Secondary analysis of whole blood DNA methylation data generated from a nested case-control study of critically ill septic and nonseptic patients. SETTING: Four tertiary care hospitals in Canada. INTERVENTIONS: None. PATIENTS: Critically ill patients with and without sepsis. MEASUREMENTS AND MAIN RESULTS: Epigenetic age was derived from DNA methylation data using the Hannum and PhenoAge algorithms and deviation from the patient's chronological age in years was determined. Of the 66 patients with sepsis, 34 were male (51.5%), the mean age was 65.03 years and 25 patients (37.8%) died before discharge. Of the 68 nonseptic patients, 47 were male (69.1%), the mean age was 64.92 years and 25 (36.7%) died before discharge. Epigenetic age calculated using the PhenoAge algorithm showed a significant age acceleration of 4.97 years in septic patients (p = 0.045), but no significant acceleration in nonseptic patients. Epigenetic age calculated using the Hannum algorithm showed no significant acceleration in the septic or nonseptic patients. Similarly, in the combined septic and nonseptic cohorts, nonsurvivors showed an epigenetic age acceleration of 7.62 years (p = 0.004) using the PhenoAge algorithm while survivors showed no significant age acceleration. Survivor status was not associated with age acceleration using the Hannum algorithm. CONCLUSIONS: In critically ill patients, epigenetic age acceleration, as calculated by the PhenoAge algorithm, was associated with sepsis diagnosis and mortality.
ABSTRACT
The purpose of this study was to investigate whether a tethered-swimming incremental test comprising small increases in resistive force applied every 60 seconds could delineate the isocapnic region during rapidly-incremented exercise. Sixteen competitive swimmers (male, n = 11; female, n = 5) performed: (a) a test to determine highest force during 30 seconds of all-out tethered swimming (Favg) and the ΔF, which represented the difference between Favg and the force required to maintain body alignment (Fbase), and (b) an incremental test beginning with 60 seconds of tethered swimming against a load that exceeded Fbase by 30% of ΔF followed by increments of 5% of ΔF every 60 seconds. This incremental test was continued until the limit of tolerance with pulmonary gas exchange (rates of oxygen uptake and carbon dioxide production) and ventilatory (rate of minute ventilation) data collected breath by breath. These data were subsequently analyzed to determine whether two breakpoints defining the isocapnic region (i.e., gas exchange threshold and respiratory compensation point) were present. We also determined the peak rate of O2 uptake and exercise economy during the incremental test. The gas exchange threshold and respiratory compensation point were observed for each test such that the associated metabolic rates, which bound the heavy-intensity domain during constant-work-rate exercise, could be determined. Significant correlations (Spearman's) were observed for exercise economy along with (a) peak rate of oxygen uptake (ρ = .562; p < 0.025), and (b) metabolic rate at gas exchange threshold (ρ = -.759; p < 0.005). A rapidly-incremented tethered-swimming test allows for determination of the metabolic rates that define zones for domain-specific constant-work-rate training.
ABSTRACT
RESUMO Introdução: Poucos estudos analisaram a contribuição da composição regional de nadadores para o perfil aeróbio, anaeróbio e o desempenho de nado. Objetivo: Verificar a influência da composição corporal regional e total sobre índices da aptidão aeróbia e anaeróbia em nado atado e livre, bem como sobre o desempenho de curta e média duração. Métodos: Onze nadadores (18,0 ± 4,0 anos) foram submetidos a: (1) teste incremental em nado atado, com coleta de gases respiração-a-respiração (K4b2 associado ao novo-AquaTrainerâ); e (2) tempo limite nos desempenhos de 200, 400 e 800 metros de nado livre. A regressão linear entre distância e tempo (d-tLim) empregou o método dos quadrados mínimos. O coeficiente de Pearson (r) averiguou as correlações da composição corporal regional e total com índices da aptidão aeróbica e anaeróbica em nado atado e livre. Resultados: Os valores da massa isenta de gordura (MIG) foram: 61,7 ± 7,4 kg; 7,5 ± 1,1 kg; 28,3 ± 3,7 kg; 22,1 ± 2,5 kg, respectivamente para corpo todo, membros superiores (MS), tronco (T) e membros inferiores (MI). O consumo máximo de oxigênio (VO2max) foi 52,1 ± 5,3 ml×kg-1×min-1, sendo a carga correspondente (iVO2max) de 93,9 ± 12,2 N. O tempo em 200 (132,2 ± 9,7 s), 400 (296,8 ± 17,2 s) e 800 metros (619,5 ± 26,9 s) forneceu velocidade crítica (VC = 1,23 ± 0,06 m×s-1) e capacidade anaeróbica de nado (CNA = 35,8 ± 15,1 m). Observaram-se correlações de iVO2max, CAN e v200m com MIG para MS (r = 0,64; 0,67 e 0,76), porém a MIG para T, MI e corporal demonstraram correlações apenas com v200m (r = 0,75; 0,69 e 0,75) e CAN (r = 0,71; 0,69 e 0,75). Conclusão: Houve, portanto, influência da MIG regional e corporal sobre o desempenho de curta distância e reservas anaeróbias, sendo a MIG-MS também influente sobre a iVO2max, e assim relacionada ao aprimoramento do desempenho de nado.
ABSTRACT Introduction: There have been few studies analyzing the regional body contribution of swimmers for aerobic and anaerobic profiles and swimming performance. Objective: To verify the influence of regional and whole-body composition on aerobic and anaerobic fitness indices in free and tethered swimming, as well as short- and medium-term performance. Methods: Eleven swimmers (18.0 ± 4.0 years old) were submitted to: (1) an incremental test in tethered swimming, with breath-by-breath gas exchange sampling (K4b2 associated with the new-AquaTrainerâ), and (2) timeout while performing the 200, 400 and 800 meter freestyle. Linear regression analysis between distance and time (d-tLim) was performed using the least squares method. Pearson's coefficient (r) was used to test the correlations between regional and whole-body composition and aerobic and anaerobic fitness indices in freestyle and tethered swimming. Results: Mean values for fat free mass (FFM) were: 61.7±7.4 kg; 7.5±1.1 kg; 28.3±3.7 kg; 22.1±2.5 kg, respectively, for the whole-body, upper-limbs (UL), trunk (T) and lower-limbs (LL). Maximal oxygen uptake (VO2max) was 52.1±5.3 ml×kg-1×min-1, and respective load (iVO2max) was 93.9 ± 12.2 N. The timeout in 200 (132.2±9.7 s), 400 (296.8±17.2 s) and 800 meters (619.5±26.9 s) provided critical velocity (CV = 1.23±0.06 m×s-1) and anaerobic swimming capacity (ASC = 35.8±15.1 m). Correlations were observed for iVO2max, ASC and v200m with FFM for UL (r = 0.64; 0.67 and 0.76), but FFM for T, LL and whole body were related only with v200m (r = 0.75; 0.69 and 0.75) and ASC (r = 0.71; 0.69 and 0.75). Conclusion: Regional and whole-body FFM influenced short-term performance and anaerobic reserves; FFM for UL was also related to iVO2max, and was therefore associated with improved swimming performance.
RESUMEN Introducción: Pocos estudios han examinado la contribución de la composición regional de los nadadores para el perfil aerobio, anaerobio y el rendimiento de nado. Objetivo: Verificar la influencia de la composición corporal regional y total sobre índices de aptitud aerobia y anaerobia en nado estacionario y libre, así como sobre el rendimiento de corta y media duración. Métodos: Once nadadores (18,0 ± 4,0 años) fueron sometidos a: (1) test incremental en nado estacionario, con coleta de gases respiración a respiración (K4b2 asociado al nuevo-AquaTrainerâ); y (2) tiempo límite en el rendimiento de 200, 400 y 800 metros en nado libre. La regresión lineal entre la distancia y el tiempo (d-tLim) utilizó el método de los mínimos cuadrados. Se empleó el coeficiente de Pearson (r) para examinar las correlaciones entre la composición corporal regional y total con los índices de capacidad aerobia y anaerobia en el nado estacionario y en el nado libre. Resultados: Los valores de masa libre de grasa (MLG) fueron: 61,7±7,4 kg; 7,5±1,1 kg; 28,3±3,7 kg; 22,1±2,5 kg, respectivamente, para todo el cuerpo, extremidades superiores (ES), tronco (T) y extremidades inferiores (EI). El consumo máximo de oxígeno (VO2máx) fue 52,1 ± 5,3 ml×kg-1×min-1, y la carga correspondiente (iVO2máx) fue 93,9 ± 12,2 N. El tiempo en 200 (132,2 ± 9,7 s), 400 (296,8 ± 17,2 s) y 800 metros (619,5 ± 26,9 s) estableció la velocidad crítica (VC = 1,23±0,06 m×s-1) y la capacidad del nado anaerobia (CNA = 35,8 ± 15,1 m). Se verificaron correlaciones entre iVO2máx, CNA y v200m con MLG de ES (r = 0,64, 0,67 y 0,76), pero la MLG para T, EI y corporal demostraron correlaciones sólo con la v200m (r = 0,75, 0,69 y 0,75) y la CNA (r = 0,71, 0,69 y 0,75). Conclusión: Por lo tanto, hubo influencia de la MLG regional y total en el rendimiento a corto plazo y en las reservas anaerobias, mientras la MLG-ES influye en la iVO2máx y así en la mejora del rendimiento en la natación.
