Chronotropic incompetence is associated with reduced aerobic conditioning and sedentary behavior in patients with post-acute COVID-19 syndrome.

Post-acute COVID-19 syndrome, or long COVID, presents with persistent symptoms, including cough, dyspnea, and fatigue, extending beyond one month after SARS-CoV-2 infection. Cardiac complications such as chest pain and arrhythmias have raised concerns, with chronotropic incompetence (CI), an inadequate heart rate increase during exercise, emerging as a significant condition contributing to diminished exercise tolerance and quality of life. This study estimated the prevalence of CI and explored its association with aerobic capacity and physical activity levels in long COVID patients. A cross-sectional study was conducted at a private hospital in Sergipe, Brazil, involving 93 patients over 18 years old with persistent post-COVID-19 symptoms after confirmed SARS-CoV-2 infections. Exclusion criteria included beta-blocker use, inadequate respiratory exchange ratio, and inability to complete cardiopulmonary exercise testing (CPET). Clinical histories, CPET results, and chronotropic index calculation were used to identify CI, with logistic regression analyzing associated factors. Of the participants (mean age 45 years; average duration since COVID-19 diagnosis 120 days), 20.4% were diagnosed with CI. Logistic regression identified a strong association between CI and sedentary behavior (OR 11.80; 95% CI 2.54 to 54.78; p=0.001). Patients with CI showed lower predicted peak heart rates and maximal oxygen uptake. The prevalence of CI among long COVID patients in this study was approximately 20%, associated with decreased aerobic capacity and increased sedentary behavior. These findings highlight the need for timely diagnosis and therapeutic interventions, including cardiopulmonary rehabilitation, to enhance the quality of life in post-COVID patients with CI. The study's cross-sectional design and its specific context have limited causality inference and generalizability, underscoring the importance of further research in diverse settings.

Demographic, socioeconomic, and health structure factors associated with the use of HIV pre-exposure prophylaxis in Brazil: A nationwide ecological study.

Aims: To assess the cumulative rate of HIV Pre-Exposure Prophylaxis (PrEP) users in Brazil since its 2018 implementation and to analyze the association between PrEP usage and state-level structural factors. Methods: A nationwide ecological study from 2018 to 2022 was conducted, examining the 5-year cumulative rate of PrEP users in relation to demographic, socioeconomic, and healthcare infrastructure variables. Multiple linear regression analysis identified significant predictors of PrEP utilization. Results: Between 2018 and 2022, 124,796 individuals used PrEP, with a cumulative rate of 61.5 per 100,000 population. The highest usage was in Minas Gerais, São Paulo, and Santa Catarina, while the lowest was in Distrito Federal, Maranhão, and Alagoas. Regression analysis showed that higher PrEP usage was associated with lower population density, a younger median age, a lower male to female ratio, and reduced social vulnerability. Additionally, PrEP usage was positively associated with the density of medical doctors and the number of dispensing units. Conclusions: The study reveals significant regional disparities in PrEP usage across Brazil, influenced by socioeconomic and healthcare factors. It highlights the need for targeted public health strategies to enhance PrEP access and uptake, especially in socially vulnerable regions.

Long-Term Impact of Left Bundle Branch Block on Cardiopulmonary Exercise Test Variables and Left Ventricular Systolic Function: A Two-Stage Observational Study.

INTRODUCTION: Left bundle branch block (LBBB) disrupts the electrical activation of the left ventricle (LV), potentially impairing its systolic function, leading to LBBB-induced cardiomyopathy. This study examined cardiopulmonary exercise test (CPET) variables in patients with and without LBBB and assessed the longitudinal development of left ventricular ejection fraction (LVEF). METHOD: An observational, comparative clinical study was executed in two stages at a private hospital in Brazil. The sample consisted of 27 individuals: 11 with LBBB and 16 without LBBB, all with preserved LVEF (>50%) and without confirmed ischemia. CPET variables were assessed, and after four years, participants had a transthoracic echocardiogram (TTE) for LVEF re-evaluation. Groups were compared using the t-test or the Chi-square (X²) test. Multivariate analysis of covariance (MANCOVA) determined effect magnitude. RESULTS: Patients with LBBB demonstrated significant differences in CPET variables, particularly in predicted peak V̇O2, predicted peak PO2, V̇E/V̇CO2 slope, and T½V̇O2. They also exhibited a more significant decline in LVEF over a four-year span compared to the patients without LBBB. Although initial preservation of LVEF, changes in contractile patterns due to LBBB interfered with its systolic function, suggesting early ventricular dysfunction indicated by a reduction in LVEF and an increase in the V̇E/V̇CO2 slope. Despite differences in cardiopulmonary function and changes in LVEF over time between patients with and without LBBB, the effect size was considered mild to moderate. CONCLUSIONS: LBBB patients with initially preserved LVEF displayed reduced exercise tolerance and a decrease in LVEF over time, emphasizing the need for vigilant monitoring and early intervention in these patients.

Comparative analysis of masseter muscle electrical activity by nasal patency in children with rhinitis and asthma: a pilot observational study.

PURPOSE: This pilot cross-sectional study aimed to evaluate differences in electromyographic activity patterns of the masseter muscle according to the nasal patency in children with rhinitis and asthma. METHODS: The study included 43 children aged 5-14 years with rhinitis and/or asthma. Patients underwent peak nasal inspiratory flow (PNIF) measurement to assess nasal patency, and electromyographic evaluation of the right and left masseter muscles during chewing and at rest. Electromyographic activity patterns according to nasal patency were compared using the Mann-Whitney test, and effect sizes were measured using the Glass rank biserial (rb) correlation. A p-value of < 0.05 was considered statistically significant. RESULTS: No significant differences in electromyographic activity of the masseter muscle at rest, during unilateral chewing, or during habitual chewing were found between the groups. However, we found that patients with low nasal patency had a median electric activity of the right masseter muscle during maximum contraction of 60.53 (51.74-72.43), while those with adequate nasal patency had a median of 77.40 (56.71-88.45). Although the difference in myoelectric activity between the groups did not reach statistical significance (p = 0.061) at the adopted significance level of 5%, the size of the difference between groups were considered moderate (rb = 0.338) and a potential association between nasal patency and the muscular function of the masseter muscle could be suggested. CONCLUSION: The study found no differences in the electromyographic activity of the masseter muscle at rest, during unilateral chewing, or during habitual chewing among children with rhinitis and asthma based on nasal patency. Further research with larger sample sizes is needed to validate these findings and gain a better understanding of the impact of nasal patency on the muscular function of the masseter muscle.

Cardiorespiratory optimal point in post-COVID-19 patients: a cross-sectional study.

The varied clinical presentations of SARS-CoV-2 infection have raised concerns about long-term consequences, especially "long-COVID" or "post-COVID-19 syndrome." In this context, the cardiorespiratory optimal point (COP) within the Cardiopulmonary Exercise Test (CPET) emerges as a crucial metric for evaluating functional capacities and detecting cardiovascular and pulmonary anomalies post-COVID-19. This study aimed to assess COP values among post-COVID-19 patients and categorized them based on the initial severity of their disease. In this cross-sectional study conducted in the Northeast Brazil, 80 patients (26 females and 54 males) previously infected with SARS-CoV-2 underwent CPET. We clinically stratified patients into mild, moderate, or severe COVID-19 categories and assessed COP values and other cardiorespiratory metrics. We found differences in the predicted COP between patients with mild and severe COVID-19 (p=0.042). Additionally, patients with moderate and severe COVID-19 record had an average COP value exceeding 22. Other parameters, including respiratory exchange ratio, heart rate, and oxygen uptake efficiency slope, did not differ across the groups. Patients with a history of severe COVID-19 showed altered COP values, suggesting potential discrepancies in cardiovascular and respiratory system integration. The outcomes emphasize the importance of continuous monitoring and assessment of the cardiorespiratory domain for post-COVID-19 patients. Further research is needed to understand the relationship between elevated COP in post-severe COVID-19 and its long-term prognostic implications.

Cardiorespiratory optimal point in post-COVID-19 patients: a cross-sectional study

ABSTRACT The varied clinical presentations of SARS-CoV-2 infection have raised concerns about long-term consequences, especially "long-COVID" or "post-COVID-19 syndrome." In this context, the cardiorespiratory optimal point (COP) within the Cardiopulmonary Exercise Test (CPET) emerges as a crucial metric for evaluating functional capacities and detecting cardiovascular and pulmonary anomalies post-COVID-19. This study aimed to assess COP values among post-COVID-19 patients and categorized them based on the initial severity of their disease. In this cross-sectional study conducted in the Northeast Brazil, 80 patients (26 females and 54 males) previously infected with SARS-CoV-2 underwent CPET. We clinically stratified patients into mild, moderate, or severe COVID-19 categories and assessed COP values and other cardiorespiratory metrics. We found differences in the predicted COP between patients with mild and severe COVID-19 (p=0.042). Additionally, patients with moderate and severe COVID-19 record had an average COP value exceeding 22. Other parameters, including respiratory exchange ratio, heart rate, and oxygen uptake efficiency slope, did not differ across the groups. Patients with a history of severe COVID-19 showed altered COP values, suggesting potential discrepancies in cardiovascular and respiratory system integration. The outcomes emphasize the importance of continuous monitoring and assessment of the cardiorespiratory domain for post-COVID-19 patients. Further research is needed to understand the relationship between elevated COP in post-severe COVID-19 and its long-term prognostic implications.

Differences in volume, density, electrolyte concentration, and total proteins in the fluid of the paranasal sinuses of freshwater and saltwater drowning victims: a systematic review and meta-analysis.

This study summarized the available evidence on the differences in volume, density, electrolyte concentration, and total proteins in paranasal sinus fluid between freshwater and saltwater drowning victims. A systematic search was conducted in electronic databases and gray literature, resulting in the inclusion of five studies with 234 drowning victims (92 saltwater incidents and 142 freshwater incidents). Meta-analyses using the inverse-of-variance method and a random-effects model were performed, reporting effect sizes as standardized mean differences (SMD) with 95% confidence intervals (CI). The findings showed a significantly higher sinus density in saltwater drowning cases compared to freshwater drowning cases (SMD 0.91, 95% CI 0.50 to 1.32). However, no significant differences were observed in sinus fluid volume. Saltwater drowning victims exhibited higher electrolyte concentrations (sodium: SMD 3.77, 95% CI 3.07 to 4.48; potassium: SMD 0.78, 95% CI 0.07 to 1.49; chloride: SMD 3.48, 95% CI 2.65 to 4.31; magnesium: SMD 4.01, 95% CI 3.00 to 5.03) and lower total protein concentrations (SMD - 1.20, 95% CI - 1.82 to - 0.58) in sinus fluid compared to freshwater drowning victims. This meta-analysis highlights the importance of analyzing the characteristics and composition of sinus fluid in forensic investigations of drowning cases. While no differences were found in sinus fluid volume, saltwater drowning victims exhibited higher sinus density, elevated electrolyte concentrations, and lower total protein concentrations compared to freshwater drowning victims.

Prevalence of sleep disorders in children with Congenital Zika Syndrome.

Studies have reported that children with Congenital Zika Syndrome (CZS) experience changes in their sleep patterns, which can result in mood disturbances, behavioral issues and delays in growth and development. This systematic review synthesized the available evidence on the prevalence of sleep disorders in children with CZS. Eligible studies were those with an observational design that reported sleep disorders in children with CZS using validated questionnaires, polysomnography/electroencephalographic recording or parent/caregiver reports. Searches were conducted in PubMed, Web of Science, SCOPUS and Embase, as well as a gray literature search using Google Scholar. The Freeman-Tukey double-arcsine transformation with a random-effects model was used to estimate the pooled prevalence of sleep disorders with a 95% confidence interval (CI). Five studies were included and data from 340 Brazilian children with CZS were analyzed. The overall prevalence of sleep disorders was 27.4% (95% CI 16.7-39.4), without differences among studies using validated questionnaires (29.4%, 95% CI 21.4-37.8) or report from parents and caregivers (27.4%, 95% CI 11.5-47.0). Sleep disorders are prevalent in children with CZS, impacting their development and quality of life. It is critical to examine the quality of sleep in these children to develop appropriate interventions that can mitigate these issues.

The article discusses a systematic review of studies that have explored the prevalence of sleep disorders in children with Congenital Zika Syndrome (CZS), a condition caused by the Zika virus. The study found that children with CZS often experience changes in their sleep patterns, which can lead to mood disturbances, behavioral issues and delays in growth and development. The review included five studies with a total of 340 Brazilian children with CZS, and the overall prevalence of sleep disorders was found to be 27.4%. This indicates that sleep disorders are prevalent in children with CZS and can significantly impact their development and quality of life. The authors suggest that further research is needed to develop appropriate interventions to mitigate these issues.