Post-COVID-19 Parkinsonism and Parkinson's Disease Pathogenesis: The Exosomal Cargo Hypothesis.

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease after Alzheimer's disease, globally. Dopaminergic neuron degeneration in substantia nigra pars compacta and aggregation of misfolded alpha-synuclein are the PD hallmarks, accompanied by motor and non-motor symptoms. Several viruses have been linked to the appearance of a post-infection parkinsonian phenotype. Coronavirus disease 2019 (COVID-19), caused by emerging severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, has evolved from a novel pneumonia to a multifaceted syndrome with multiple clinical manifestations, among which neurological sequalae appear insidious and potentially long-lasting. Exosomes are extracellular nanovesicles bearing a complex cargo of active biomolecules and playing crucial roles in intercellular communication under pathophysiological conditions. Exosomes constitute a reliable route for misfolded protein transmission, contributing to PD pathogenesis and diagnosis. Herein, we summarize recent evidence suggesting that SARS-CoV-2 infection shares numerous clinical manifestations and inflammatory and molecular pathways with PD. We carry on hypothesizing that these similarities may be reflected in exosomal cargo modulated by the virus in correlation with disease severity. Travelling from the periphery to the brain, SARS-CoV-2-related exosomal cargo contains SARS-CoV-2 RNA, viral proteins, inflammatory mediators, and modified host proteins that could operate as promoters of neurodegenerative and neuroinflammatory cascades, potentially leading to a future parkinsonism and PD development.

The Effect of Whole-Body Cryostimulation in Healthy Adults : Whole-Body Cryostimulation According to Gender and Smoking Status.

INTRODUCTION: Whole-body cryostimulation (WBC) refers to the therapeutic application of extremely cold dry air for a short period of time. The method has beneficial results in various diseases as well as the recovery of athletes. The effects of WBC in healthy individuals have not been extensively investigated. PURPOSE: We aim to explore differences in the effects of WBC on blood pressure (BP), oxygen saturation (SpO2), and heart rate (HR) in healthy adults (not athletes) as well as differences according to gender and smoking status. MATERIALS AND METHODS: Fifty adults (male/female: 32/18) smokers/nonsmokers: 26/24) were included in the study. WBC was performed in a cryochamber at -85 °C for 3 min. Systolic BP (SBP) and diastolic BP (DBP), HR, and SpO2 were measured before and immediately after WBC. RESULTS: Males and females differed significantly in SBP after WBC (138.1 ± 13.0 vs 128.5 ± 17.0 mmHg, respectively, p = 0.029), SpO2 after WBC (96.6 ± 1.8 vs 98.3 ± 1.5%, respectively, p = 0.001) and HR after WBC (60.1 ± 9.6 vs 70.2 ± 7.7 bpm, respectively, p < 0.001). In males, SpO2 remained unchanged before and after WBC, whereas in women SpO2 increased by 1.0 ± 1.4% (p = 0.038) (Table 2). HR after WBC displayed a downward trend by -9.8 ± 5.9% in males compared to an upward trend by 3.6 ± 15.1 in females (p < 0.001). Nonsmokers displayed higher increase in SBP after WBC (4.3 ± 9.0% in smokers compared to 13.3 ± 13.2% in nonsmokers, p = 0.007). Smokers presented an increase by 1.0 ± 1.6% in SpO2, while in nonsmokers, SpO2 decreased by 0.8 ± 2.1% following WBC (p = 0.001). CONCLUSIONS: Our results suggest that WBC affects the cardiovascular and the respiratory system differently in males versus females and smokers versus nonsmokers. More studies are needed in order to fully explore the effects of WBC in these population groups in order to design individualized treatment protocols.

Impact of Isolated Exercise-Induced Small Airway Dysfunction on Exercise Performance in Professional Male Cyclists.

BACKGROUND: Professional cycling puts significant demands on the respiratory system. Exercise-induced bronchoconstriction (EIB) is a common problem in professional athletes. Small airways may be affected in isolation or in combination with a reduction in forced expiratory volume at the first second (FEV1). This study aimed to investigate isolated exercise-induced small airway dysfunction (SAD) in professional cyclists and assess the impact of this phenomenon on exercise capacity in this population. MATERIALS AND METHODS: This research was conducted on professional cyclists with no history of asthma or atopy. Anthropometric characteristics were recorded, the training age was determined, and spirometry and specific markers, such as fractional exhaled nitric oxide (FeNO) and immunoglobulin E (IgE), were measured for all participants. All of the cyclists underwent cardiopulmonary exercise testing (CPET) followed by spirometry. RESULTS: Compared with the controls, 1-FEV3/FVC (the fraction of the FVC that was not expired during the first 3 s of the FVC) was greater in athletes with EIB, but also in those with isolated exercise-induced SAD. The exercise capacity was lower in cyclists with isolated exercise-induced SAD than in the controls, but was similar to that in cyclists with EIB. This phenomenon appeared to be associated with a worse ventilatory reserve (VE/MVV%). CONCLUSIONS: According to our data, it appears that professional cyclists may experience no beneficial impacts on their respiratory system. Strenuous endurance exercise can induce airway injury, which is followed by a restorative process. The repeated cycle of injury and repair can trigger the release of pro-inflammatory mediators, the disruption of the airway epithelial barrier, and plasma exudation, which gradually give rise to airway hyper-responsiveness, exercise-induced bronchoconstriction, intrabronchial inflammation, peribronchial fibrosis, and respiratory symptoms. The small airways may be affected in isolation or in combination with a reduction in FEV1. Cyclists with isolated exercise-induced SAD had lower exercise capacity than those in the control group.

The impact of a 12-week tele-exercise program on cognitive function and cerebral oxygenation in patients with OSA: randomized controlled trial-protocol study.

Obstructive sleep apnea (OSA) is associated with a number of adverse health effects, particularly on brain health. Chronic sleep disruption caused by OSA can adversely affect cognitive health. Exercise is recommended as a non-pharmacological intervention for patients who are intolerant to continuous positive airway pressure (CPAP) and has been shown to have beneficial effects on brain health and cognitive function. This protocol aims to investigate the effects of a 12-week tele-exercise program on cognitive function and specific parameters of brain activity, including brain metabolism and oxygenation, in patients with OSA. The project aims to demonstrate the multidimensional relationship between exercise, cognition, and brain oxygenation/metabolism. Our local ethics committee has approved the study. Our population sample (Group A, OSA with cognitive impairment (CI) and tele-exercise; Group B, OSA with CI and no tele-exercise; Group C, OSA without CI and no tele-exercise) will undergo assessment both before and after a 12-week tele-exercise intervention program. This assessment will include a comprehensive battery of subjective and objective assessment tests. Data will be analyzed according to group stratification. We hypothesize a beneficial effect of tele-exercise on sleep and cognitive parameters, and we are confident that this study will raise awareness among healthcare professionals of the brain health benefits of exercise in patients with low compliance to CPAP treatment. The protocol of our manuscript entitled "The impact of a 12-week tele-exercise program on cognitive function and cerebral oxygenation in patients with OSA: Randomized Controlled Trial -Protocol Study" has been registered on ClinicalTrials.gov with ID NCT06467682.

Sleep Quality in Greek Adolescent Swimmers.

The aim of our study was to investigate the relationship between sleep quality and functional indices, swimming distance and gender in adolescent competitive swimmers. Forty-eight adolescent swimmers (boys, n = 22, 15.7 ± 1.0 years and girls, n = 26, 15.1 ± 0.8 years) were included in our study. They were assessed for handgrip strength, respiratory muscle strength and pulmonary function, answered a Pittsburg Sleep Quality Index questionnaire (PSQI), and recorded their anthropometric and morphological characteristics and training load for the last four weeks. The results showed differences between swimming distance and chest circumference difference, between maximal inhalation and exhalation (Δchest) (p = 0.033), PSQI score (p < 0.001), and sleep quality domains for "cannot breathe comfortably" (p = 0.037) and "have pain" (p = 0.003). Binary logistic regression (chi-square = 37.457, p = 0.001) showed that the variables Δchest (p = 0.038, 95% CI: 1.05-6.07) and PSQI score (p = 0.048, 95% CI: 0.1-1.07) remained independent predictors of the swim distance groups. Girls had a lower percentage of predicted values for the maximal inspiratory pressure (p < 0.001), maximal expiratory pressure (p = 0.027), forced expiratory volume within the first second (p = 0.026), forced vital capacity (p = 0.008) and sleep quality domains for "cough or snore loudly" (p = 0.032) compared to boys. A regression analysis showed that the sleep quality score was explained by the six independent variables: respiratory muscle strength (t = 2.177, ß = 0.164, p = 0.035), Δchest (t = -2.353, ß = -0.17, p = 0.023), distance (t = -5.962, ß = -0.475, p < 0.001), total body water (t = -7.466, ß = -0.687, p < 0.001), lean body mass (t = -3.120, ß = -0.434, p = 0.003), and handgrip (t = 7.752, ß = 1.136, p < 0.001). Our findings demonstrate that sleep quality in adolescent swimmers is a multifactorial result of morphometric characteristics, strength and respiratory function.

Exploring the Acute Effects of Immersive Virtual Reality Biking on Self-Efficacy and Attention of Individuals in the Treatment of Substance Use Disorders: A Feasibility Study.

BACKGROUND: The role of exercise programs during substance use disorder (SUD) treatment is considered particularly supportive in fostering positive psychological and behavioral changes. The treatment of SUD is a challenging and demanding process. Therefore, it is crucial to discover innovative methods to enhance and facilitate it. Integrating exercise into a virtual environment is an innovative approach for drug rehabilitation, offering multiple benefits to individuals undergoing treatment. The aim of this feasibility study was to explore the acute effects of cycling exercise in an immersive virtual reality (VR) environment on attentional control and self-efficacy expectations of individuals undergoing SUD treatment. METHODS: A total of 20 individuals (mean age of 37.75 years) enrolled in a SUD treatment program participated in the study. They were instructed to complete a single session of cycling with a self-selected duration within the VR system. RESULTS: Following the cycling session, pre-post measures indicated a statistically significant improvement in self-efficacy expectations and attentional control measured with the Stroop test. The results revealed that participants expressed high levels of intention for future use, interest/enjoyment, and positive attitudes toward the VR exercise system. Qualitative data indicated that participants found the VR exercise system enjoyable, expressed a strong intention to use it, and did not encounter technical difficulties or negative emotions. CONCLUSIONS: In conclusion, it seems that engaging in a brief period of self-selected exercise within a virtual environment can result in temporary activation of cognitive changes, heightened self-efficacy expectations, and a motivating approach to increasing physical activity participation among individuals with SUD, thus suggesting the feasibility of this approach.

The Impact of Different Exercise Modes in Fitness and Cognitive Indicators: Hybrid versus Tele-Exercise in Patients with Long Post-COVID-19 Syndrome.

The purpose of our study was to obtain evidence that an unsupervised tele-exercise program (TEgroup) via an online platform is a feasible alternative to a hybrid mode of supervised and unsupervised exercise (HEgroup) sessions for improving fitness indexes, respiratory and cognitive functions, and biomarkers of oxidative stress in patients recovering from COVID-19. Forty-nine patients with long post-COVID-19 were randomly divided into two groups (HEgroup: n = 24, age 60.0 ± 9.5 years versus TEgroup: n = 25, age 58.7 ± 9.5 years). For each patient, we collected data from body composition, oxidative stress, pulmonary function, physical fitness, and cognitive function before and after the 12-week exercise rehabilitation program (ERP). Our data showed differences in both groups before and after 12-week ERP on fitness indicators, body composition, and pulmonary function indicators. Our findings demonstrated differences between groups after 12-week ERP on adjustment in the domains of cognitive function (HEgroup increased the "visuospatial" domain: 3.2 ± 1.1 versus 3.5 ± 0.8 score, p = 0.008 and TEgroup increased the "memory" domain: 3.3 ± 1.0 versus 3.8 ± 0.5 score, p = 0.003; after 12-week ERP showed differences between groups in domain "attention" TEgroup: 4.8 ± 1.5 versus HEgroup: 3.6 ± 1.8 score, p = 0.014) and the diffusing capacity for carbon monoxide (HEgroup increased the percent of predicted values at 0.5 ± 32.3% and TEgroup at 26.0 ± 33.1%, p < 0.001). These findings may be attributed to the different ways of learning exercise programs, resulting in the recruitment of different neural circuits.

The Effect of Growth and Body Surface Area on Cardiopulmonary Exercise Testing: A Cohort Study in Preadolescent Female Swimmers.

BACKGROUND: The performance of young swimmers is the result of a multifactorial process that is influenced by anthropometric characteristics and biological maturation. The purpose of our study was to investigate the effect of stages of biological maturation and body surface area on cardiopulmonary fitness indicators in preadolescent female swimmers, for whom menstruation has not started. METHODS: Thirty female preadolescent swimmers (age 13.4 ± 1.0 years) participated in this study. We recorded anthropometric and morphological characteristics, stages of biological maturation, and pulmonary function parameters, and the swimmers underwent cardiopulmonary exercise testing. RESULTS: The cut-off was set for body surface area (BSA) at 1.6 m2 and for biological maturation stages at score 3. The BSA results showed differences in variabilities in maximal effort oxygen pulse (p < 0.001), oxygen uptake (p < 0.001), ventilation (p = 0.041), tidal volume (p < 0.001), and oxygen breath (p < 0.001). Tanner stage score results showed differences in variabilities in maximal effort breath frequency (p < 0.001), tidal volume (p = 0.013), and oxygen breath (p = 0.045). Biological maturation stages and BSA were correlated during maximal effort with oxygen breath (p < 0.001; p < 0.001), oxygen uptake (p = 0.002; p < 0.001), and oxygen pulse (p < 0.001; p < 0.001). CONCLUSIONS: In conclusion, the findings of our study showed that the girls who had a smaller body surface area and biological maturation stage presented lower values in maximal oxygen uptake and greater respiratory work.

Pulmonary Function Test: Relationship Between Adolescent Swimmers and Finswimmers.

INTRODUCTION: The aim of our study was to investigate the effects of training on the static and dynamic respiratory parameters in adolescent female swimmers (SWs) and finswimmers (FSWs). METHODS:  Forty-six female adolescent SWs (n=24, age=17.6±0.7 years) and FSWs (n=22, age=17.0±1.2 years) volunteered for this study. All participants underwent standard spirometry and lung volume measurements and were collected anthropometrical and morphological characteristics. RESULTS: The results of the groups in the pulmonary function test parameters, namely, inspiratory capacity (IC), expiratory reserve volume (ERV), and peak expiratory flow (PEF), were significantly different. Higher values of IC, ERV, and PEF were observed in the FSW group than the SW group: IC = 116.5±13.2 (SWs) vs. 125.5±11.5 (FSWs) % of predicted, p = 0.019; ERV = 121.8±14.8 (SWs) vs. 130.6±12.5 (FSWs) % of predicted, p = 0.036; PEF = 111.6±7.5 (SWs) vs. 116.3±5.0 (FSWs) % of predicted, p = 0.018. CONCLUSION:  The differences between groups probably reflect the activation of different muscle groups.

Effect of Hydration on Pulmonary Function and Development of Exercise-Induced Bronchoconstriction among Professional Male Cyclists.

BACKGROUND: Exercise-induced bronchoconstriction (EIB) is a common problem in elite athletes. Classical pathways in the development of EIB include the osmotic and thermal theory as well as the presence of epithelial injury in the airway, with local water loss being the main trigger of EIB. This study aimed to investigate the effects of systemic hydration on pulmonary function and to establish whether it can reverse dehydration-induced alterations in pulmonary function. MATERIALS AND METHODS: This follow-up study was performed among professional cyclists, without a history of asthma and/or atopy. Anthropometric characteristics were recorded for all participants, and the training age was determined. In addition, pulmonary function tests and specific markers such as fractional exhaled nitric oxide (FeNO) and immunoglobulin E (IgE) were measured. All the athletes underwent body composition analysis and cardiopulmonary exercise testing (CPET). After CPET, spirometry was followed at the 3rd, 5th, 10th, 15th, and 30th min. This study was divided into two phases: before and after hydration. Cyclists, who experienced a decrease in Forced Expiratory Volume in one second (FEV1) ≥ 10% and/or Maximal Mild-Expiratory Flow Rate (MEF25-75) ≥ 20% after CPET in relation to the results of the spirometry before CPET, repeated the test in 15-20 days, following instructions for hydration. RESULTS: One hundred male cyclists (n = 100) participated in Phase A. After exercise, there was a decrease in all spirometric parameters (p < 0.001). In Phase B, after hydration, in all comparisons, the changes in spirometric values were significantly lower than those in Phase A (p < 0.001). CONCLUSIONS: The findings of this study suggest that professional cyclists have non-beneficial effects on respiratory function. Additionally, we found that systemic hydration has a positive effect on spirometry in cyclists. Of particular interest are small airways, which appear to be affected independently or in combination with the decrease in FEV1. Our data suggest that pulmonary function improves systemic after hydration.

Athletes with mild post-COVID-19 symptoms experience increased respiratory and metabolic demands: Α cross-sectional study.

Coronavirus Disease 2019 (COVID-19) has significantly affected different physiological systems, with a potentially profound effect on athletic performance. However, to date, such an effect has been neither addressed nor investigated. Therefore, the aim of this study was to investigate fitness indicators, along with the respiratory and metabolic profile, in post-COVID-19 athletes. Forty male soccer players, were divided into two groups: non-hospitalized COVID-19 (n = 20, Age: [25.2 ±â€¯4.1] years, Body Surface Area [BSA]: [1.9 ±â€¯0.2] m2, body fat: 11.8% ±â€¯3.4%) versus [vs] healthy (n = 20, Age: [25.1 ±â€¯4.4] years, BSA: [2.0 ±â€¯0.3] m2, body fat: 10.8% ±â€¯4.5%). For each athlete, prior to cardiopulmonary exercise testing (CPET), body composition, spirometry, and lactate blood levels, were recorded. Differences between groups were assessed with the independent samples t-test (p < 0.05). Several differences were detected between the two groups: ventilation (V˙E: Resting: [14.7 ±â€¯3.1] L·min-1 vs. [11.5 ±â€¯2.6] L·min-1, p = 0.001; Maximal Effort: [137.1 ±â€¯15.5] L·min-1 vs. [109.1 ±â€¯18.4] L·min-1, p < 0.001), ratio VE/maximal voluntary ventilation (Resting: 7.9% ±â€¯1.8% vs. 5.7% ±â€¯1.7%, p < 0.001; Maximal Effort: 73.7% ±â€¯10.8% vs. 63.1% ±â€¯9.0%, p = 0.002), ratioVE/BSA (Resting: 7.9% ±â€¯2.0% vs. 5.9% ±â€¯1.4%, p = 0.001; Maximal Effort: 73.7% ±â€¯11.1% vs. 66.2% ±â€¯9.2%, p = 0.026), heart rate (Maximal Effort: [191.6 ±â€¯7.8] bpm vs. [196.6 ±â€¯8.6] bpm, p = 0.041), and lactate acid (Resting: [1.8 ±â€¯0.8] mmol·L-1 vs. [0.9 ±â€¯0.1] mmol·L-1, p < 0.001; Maximal Effort: [11.0 ±â€¯1.6] mmol·L-1 vs. [9.8 ±â€¯1.2] mmol·L-1, p = 0.009), during CPET. No significant differences were identified regarding maximal oxygen uptake ([55.7 ±â€¯4.4] ml·min-1·kg-1 vs. [55.4 ±â€¯4.6] ml·min-1·kg-1, p = 0.831). Our findings demonstrate a pattern of compromised respiratory function in post-COVID-19 athletes characterized by increased respiratory work at both rest and maximum effort as well as hyperventilation during exercise, which may explain the reported increased metabolic needs.

Breathlessness and exercise with virtual reality system in long-post-coronavirus disease 2019 patients.

Long-post-coronavirus disease-2019 (COVID-19) patients tend to claim residual symptomatology from various systems, most importantly the respiratory and central nervous systems. Breathlessness and brain fog are the main complaints. The pulmonary function pattern is consistent with restrictive defects, which, in most cases, are self-resolved, while the cognitive profile may be impaired. Rehabilitation is an ongoing field for holistic management of long-post-COVID-19 patients. Virtual reality (VR) applications may represent an innovative implementation of rehabilitation. We aimed to investigate the effect of exercise with and without the VR system and to assess further breathlessness and functional fitness indicators in long-post-COVID-19 patients with mild cognitive impairment after self-selected exercise duration using the VR system. Twenty long-post-COVID-19 patients were enrolled in our study (age: 53.9 ± 9.1 years, male: 80%, body mass index: 28.1 ± 3.1 kg/m2). Participants' anthropometric data were recorded, and they underwent pulmonary functional test evaluation as well as sleep quality and cognitive assessment. The participants randomly exercised with and without a VR system (VR vs. no-VR) and, later, self-selected the exercise duration using the VR system. The results showed that exercise with VR resulted in a lower dyspnea score than exercise without VR. In conclusion, VR applications seem to be an attractive and safe tool for implementing rehabilitation. They can enhance performance during exercise and benefit patients with both respiratory and cognitive symptoms.

Elements of Sleep Breathing and Sleep-Deprivation Physiology in the Context of Athletic Performance.

This review summarizes sleep deprivation, breathing regulation during sleep, and the outcomes of its destabilization. Breathing as an automatically regulated task consists of different basic anatomic and physiological parts. As the human body goes through the different stages of sleep, physiological changes in the breathing mechanism are present. Sleep disorders, such as obstructive sleep apnea-hypopnea syndrome, are often associated with sleep-disordered breathing and sleep deprivation. Hypoxia and hypercapnia coexist with lack of sleep and undermine multiple functions of the body (e.g., cardiovascular system, cognition, immunity). Among the general population, athletes suffer from these consequences more during their performance. This concept supports the beneficial restorative effects of a good sleeping pattern.

Tele-Exercise in Non-Hospitalized versus Hospitalized Post-COVID-19 Patients.

The purpose of our study was to investigate the effect of tele-exercise (TE) performed for 4 consecutive weeks on fitness indicators in hospitalized post-COVID-19 patients versus non-hospitalized patients. Forty COVID-19 survivors were included, and divided into two groups: non-hospitalized versus hospitalized. Body composition, anthropometric characteristics, pulmonary function tests, single-breath diffusing capacity for carbon monoxide, 6-min walk tests (6MWT) and handgrip strength tests were recorded before and after a TE regimen (3 sessions per week, 60 min each session, warm-up and cool-down with mobility exercises, aerobic exercise such as walking outdoors, and multi-joint strength exercises). Following TE, the 6-min walk distance and handgrip were increased in both groups, with a greater observed response in the non-hospitalized group (6MWT: 32.9 ± 46.6% vs. 18.5 ± 14.3%, p < 0.001; handgrip: 15.9 ± 12.3% vs. 8.9 ± 7.6%, p < 0.001). Self-assessed dyspnea and leg fatigue were reduced in both groups, while a higher percentage of reduction was observed in the non-hospitalized group (dyspnea: 62.9 ± 42.5% vs. 37.5 ± 49.0%, p < 0.05; leg fatigue: 50.4 ± 42.2% vs. 31.7 ± 45.1%, p < 0.05). Post- vs. pre-TE arterial blood pressure decreased significantly in both groups, with the hospitalized group exhibiting more prominent reduction (p < 0.001). Both groups benefited from the TE program, and regardless of the severity of the disease the non-hospitalized group exhibited a potentially diminished adaptative response to exercise, compared to the hospitalized group.

Exercise-Induced Bronchospasm in Elite Athletes.

Exercise is one of the most common triggers of exercise-induced bronchospasm (EIB), with less trained athletes showing more symptoms. Exercise-induced bronchospasm is a common and frequent problem among elite athletes with obvious implications on competing performance, health, and quality of life. Classical pathways in the development of EIB in this population include the osmotic and the thermal theory as well as the presence of epithelial injury and inflammation in the airway. Moreover, neuronic stimulation has been suggested as a potential modulator of EIB in elite athletes. In this category of population, the diagnosis of EIB is a serious challenge, especially as spirometry before and after bronchodilation is not diagnostic and specific tests are required. To date, there is no organized screening in asymptomatic elite athletes to detect EIB. This review aims to summarize the pathophysiology, clinical manipulations, and therapeutic approach of EIB in elite athletes. We searched for published studies related to the aim of this study. Exercise-induced bronchospasm is a serious and common disorder in elite athletes, and its symptoms are nonspecific with a need to confirm the diagnosis with specific tests.

COVID-19 Phenotypes and Comorbidity: A Data-Driven, Pattern Recognition Approach Using National Representative Data from the United States.

The aim of our study was to determine COVID-19 syndromic phenotypes in a data-driven manner using the survey results based on survey results from Carnegie Mellon University's Delphi Group. Monthly survey results (>1 million responders per month; 320,326 responders with a certain COVID-19 test status and disease duration <30 days were included in this study) were used sequentially in identifying and validating COVID-19 syndromic phenotypes. Logistic Regression-weighted multiple correspondence analysis (LRW-MCA) was used as a preprocessing procedure, in order to weigh and transform symptoms recorded by the survey to eigenspace coordinates, capturing a total variance of >75%. These scores, along with symptom duration, were subsequently used by the Two Step Clustering algorithm to produce symptom clusters. Post-hoc logistic regression models adjusting for age, gender, and comorbidities and confirmatory linear principal components analyses were used to further explore the data. Model creation, based on August's 66,165 included responders, was subsequently validated in data from March−December 2020. Five validated COVID-19 syndromes were identified in August: 1. Afebrile (0%), Non-Coughing (0%), Oligosymptomatic (ANCOS); 2. Febrile (100%) Multisymptomatic (FMS); 3. Afebrile (0%) Coughing (100%) Oligosymptomatic (ACOS); 4. Oligosymptomatic with additional self-described symptoms (100%; OSDS); 5. Olfaction/Gustatory Impairment Predominant (100%; OGIP). Our findings indicate that the COVID-19 spectrum may be undetectable when applying current disease definitions focusing on respiratory symptoms alone.

Memory Foam Pillow as an Intervention in Obstructive Sleep Apnea Syndrome: A Preliminary Randomized Study.

Specific pillow use is a seldom studied or controlled factor in the setting of sleep disordered breathing. The aim of this study was to investigate the effect of different pillows [own pillow (OP), memory foam pillow (MFP), generic laboratory pillow (LP)] on polysomnography (PSG)-derived parameters in patients with Obstructive Sleep Apnea Syndrome (OSAS). Thirty-two consecutive patients with OSAS were randomly allocated into two groups with randomized pillow usage [Group A: 3 h with LP and 3 h with OP (Age: 53.8 ± 12.5 years, BMI: 32.1 ± 4.6 kg/m2); Group B: 3 h with LP and 3 h with MFP (Age: 52.0 ± 6.3 years, BMI: 30.6 ± 2.2 kg/m2)]. Statistically significant differences between pillow types were detected in desaturation index and heart rate. In Group B (with MFP), a statistically significant decrease of 47.0 ± 15.9% was observed in snoring events (p < 0.05) and 10.6 ± 6.7% in their duration (p < 0.05) compared to LP. On the other hand, group A with OP recorded a decrease of 29.1 ± 32.1% in snoring events and 32.5 ± 33.1% in duration, but these values were not statistically significant (p > 0.05) compared to LP. These findings indicate that pillow type and usage, often uncontrolled in OSAS studies (contribution to the field), may impact several PSG parameters and are related to a snoring subtype of the syndrome. Secondly, they indicate that a focus on the treatment of the snoring OSAS subtype warrants further dedicated investigation.

Physical Fitness Differences, Amenable to Hypoxia-Driven and Sarcopenia Pathophysiology, between Sleep Apnea and COVID-19.

Handgrip strength is an indirect indicator of physical fitness that is used in medical rehabilitation for its potential prognostic value. An increasing number of studies indicate that COVID-19 survivors experience impaired physical fitness for months following hospitalization. The aim of our study was to assess physical fitness indicator differences with another prevalent and hypoxia-driven disease, Obstructive Sleep Apnea Syndrome (OSAS). Our findings showed differences between post-COVID-19 and OSAS groups in cardiovascular responses, with post-COVID-19 patients exhibiting higher values for heart rate and in mean arterial blood pressure. Oxygen saturation (SpO2) was lower in post-COVID-19 patients during a six-minute walking test (6MWT), whereas the ΔSpO2 (the difference between the baseline to end of the 6MWT) was higher compared to OSAS patients. In patients of both groups, statistically significant correlations were detected between handgrip strength and distance during the 6MWT, anthropometric characteristics, and body composition parameters. In our study, COVID-19 survivors demonstrated a long-term reduction in muscle strength compared to OSAS patients. Lower handgrip strength has been independently associated with a prior COVID-19 hospitalization. The differences in muscle strength and oxygenation could be attributed to the abrupt onset of the disorder, which does not allow compensatory mechanisms to act effectively. Targeted rehabilitation focusing on such residual impairments may thus be indispensable within the setting of post-COVID-19 syndrome.

Respiratory Muscle Strength: New Technology for Easy Assessment.

Respiratory muscle strength (RMS) is associated with good functionality of the respiratory system. For the general population, it refers to the quality of life, and for the athletes, is related to greater performance. In this study, a comparison was made between two different portable devices, MicroRPM (CareFusion, Kent, United Kingdom) and AirOFit PRO™ (AirOFit, Copenhagen, Denmark), assessing the maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP). Twenty-one male professional athletes were evaluated on a voluntary basis and randomly used the devices for RMS assessment, while all athletes underwent Pittsburgh Sleep Quality Index (PSQI), pulmonary function tests and ergospirometry. All measurements of MIP and MEP were made with the same methodology and all participants after the efforts answered the question "easy-operation device-information" and dyspnea and/or respiratory fatigue during trials with the CR10 scale. Results showed statistical differences between VO2max and maximal respiratory strength both for AirOFit PRO™ (r=0.526, p=0.014) and in MicroPRM (r=0.567, p=0.007). The PSQI score showed statistical differences in % of predicted values in MEP with the AirOFit PRO™ device (r=0.478, p=0.028). Athletes reported that the AirOFit PRO™ device is easier in operation as a device and provides more information during trial comparisons to MicroPRM (p=0.001). Athletes reported that the AirOFit PRO™ device is easier in operation as a device and provides more information during the trial compared to MicroPRM. The results did not show differences in RMS (MIP and MEP) between devices (p>0.05). For the people who want to train with tele-exercise and/or tele-rehabilitation, the AirOFit PRO™ device would be an important and safe training solution.

Respiratory Muscle Strength as an Indicator of the Severity of the Apnea-Hypopnea Index: Stepping Towards the Distinction Between Sleep Apnea and Breath Holding.

Background and objective The aim of this study was to investigate whether the maximum inspiratory and expiratory pressure are correlated with the apnea-hypopnea index (AHI) in patients with obstructive sleep apnea syndrome (OSAS). Methods Fifty-two patients with OSAS were divided into two groups (AHI, events/hours: <30, n=28, versus ≥30, n=24). For each patient, anthropometric characteristics, spirometry parameters, maximum inspiratory (MIP) and expiratory pressure (MEP), and cardiopulmonary function (CPF) parameters (oxygen uptake at rest (VO2), carbon dioxide output (VCO2), heart rate (HR), minute ventilation (VE), tidal volume at inspiratory (TVin) and expiratory (TVex), breath frequency (f ß), end-tidal carbon dioxide pressure (PETCO2), end-tidal oxygen pressure (PETO2), and mean arterial pressure (MAP)) in sitting position for three minutes were recorded. The independent t-test was used to measure the differences between groups (events/hours <30 versus ≥30) and Pearson correlation analysis was used for statistical comparison between parameters. Results Results showed differences between groups (AHI, events/h ≥30 versus <30) in MIP (102.0±18.3 versus 91.1±12.1 % of predicted, p=0.013) and CPF parameters TVin (0.8±0.2 versus 0.7±0.1, L, p=0.047), PETCO2 (34.6±4.2 versus 31.4±3.7, mmHg, p=0.007), and MAP (88.4±6.5 versus 82.9±6.2, mmHg, p=0.003). Pearson correlation analysis between respiratory muscle strength (MIP and MEP) and polysomnography (PSG) parameters, MIP is related to AHI (r=.332, p=0.016) and desaturation index (r=.439, p=0.001), as well as MEP to percent of REM sleep stage (r=-.564, p<0.001). Conclusion The data from the present study support that maximal inspiratory pressure relates to the severity of AHI and intermittent breath-holding during sleep increases the inspiratory muscle strength.