Association of Variability and Hypertensive Loads in 24-h Blood Pressure With Mortality and Cardiovascular Risk.

BACKGROUND: Evidence shows that high 24-h blood pressure (BP) variability increases cardiovascular risk. We investigated whether 24-h BP variability relates to mortality and cardiovascular risk due to inherent variability and/or hypertensive loads in 24-h BP. METHODS: A total of 1,050 participants from the Maracaibo Aging Study (mean age, 66 years; women, 67.2%) underwent 24-h ambulatory BP monitoring and were followed between 2001 and 2016. To evaluate inherent BP variability, we used average real variability (ARV) as it captures variability among consecutive BP readings. 24-h systolic BP load was the proportion (%) of systolic BP readings ≥130 mm Hg during the daytime and ≥110 during the nighttime. Our primary endpoint was total mortality and major adverse cardiovascular endpoints (MACE). Statistics included Cox proportional models. RESULTS: During a median follow-up of 8.3 years, 299 participants died and 210 experienced MACE. Each +2 mm Hg (corresponding to 1-standard deviation) higher 24-h systolic ARV (mean value, 9.0 ±â€…2.0 mm Hg) was associated with higher hazard ratios (HRs) for mortality by 1.28-fold (95% confidence interval [CI], 1.14-1.43) and for MACE by 1.24-fold (95% CI, 1.08-1.42). Each 30% higher 24-h systolic BP load (median value, 63%) was associated with mortality and MACE with HRs of 1.29 (95% CI, 1.15-1.46) and 1.28 (95% CI, 1.10-1.48); respectively. After models were additionally adjusted by BP level, only ARV was associated with mortality (HR, 1.17; 95% CI, 1.04-1.33) and MACE (HR, 1.16; 95% CI, 1.00-1.34). CONCLUSIONS: High ARV and hypertensive loads in 24-h systolic BP were associated with mortality and cardiovascular risk, however, only ARV is associated independently of the BP level.

Relationship of arterial stiffness and baseline vascular burden with new lacunes and microbleeds: A longitudinal cohort study.

INTRODUCTION: Arterial stiffness may have a significant impact on the development of cerebral small vessel disease (cSVD). PATIENTS AND METHODS: We obtained pulse wave velocity (24-h PWV) by means of ambulatory blood pressure monitoring (ABPM) in patients with a recent small subcortical infarct (RSSI). Patients with known cardiac or arterial embolic sources were excluded. Lacunes, microbleeds, white matter hyperintensities and enlarged perivascular spaces at baseline were assessed in a brain MRI and included in a cSVD score. A follow-up MRI was obtained 2 years later and assessed for the appearance of new lacunes or microbleeds. We constructed both unadjusted and adjusted models, and subsequently selected the optimal models based on the area under the curve (AUC) of the predicted probabilities. RESULTS: Ninety-two patients (mean age 67.04 years, 69.6% men) were evaluated and 25 had new lacunes or microbleeds during follow-up. There was a strong correlation between 24-h PWV and age (r = 0.942, p < 0.001). cSVD was associated with new lacunes or microbleeds when adjusted by age, 24-h PWV, NT-proBNP and hypercholesterolemia (OR 2.453, CI95% 1.381-4.358). The models exhibiting the highest discrimination, as indicated by their area under the curve (AUC) values, were as follows: 1 (AUC 0.854) - Age, cSVD score, 24-h PWV, Hypercholesterolemia; 2 (AUC 0.852) - cSVD score, 24-h PWV, Hypercholesterolemia; and 3 (AUC 0.843) - Age, cSVD score, Hypercholesterolemia. CONCLUSIONS: cSVD score is a stronger predictor for cSVD progression than age or hemodynamic parameters in patients with a RSSI.

Leptospirosis in horses: Sentinels for a neglected zoonosis? A systematic review.

Background and Aim: Leptospirosis is considered a neglected tropical zoonosis in low-income countries due to surveillance system limitations and non-specificity of symptoms. Humans become infected through direct contact with carrier animals or indirectly through Leptospira-contaminated environments. Conventionally, equines have been considered an uncommon source of leptospirosis, but recent publications in Latin America suggest that their role in the maintenance and dispersion of the bacteria could be more relevant than expected, as horses are susceptible to a wide variety of zoonotic Leptospira spp. from domestic and wild animals with which they share the environment. A systematic review of the published literature was conducted to compile the available information on Leptospira spp. in Ecuador, with a special focus on equine leptospirosis, to better understand the epidemiology of the bacterium and identify possible knowledge gaps. Materials and Methods: A systematic review of the published literature was conducted in PubMed, SciELO and Web of Science databases to compile the available information on Leptospira spp. in Ecuador, with a special focus on equine leptospirosis, to better understand the epidemiology of the bacterium. We used a combination of the terms (Leptospira OR Leptospirosis) AND Ecuador, without restrictions on language or publication date. Results: Our literature review reveals that published scientific information is very scarce. Eighteen full-text original scientific articles related to Leptospira or leptospirosis cases in Ecuador were included in the systematic review. Most of the studies reported data obtained from one of the four regions (Coast), and specifically from only one of the 24 Provinces of Ecuador (Manabí), which evidence a large information bias at the geographical level. Furthermore, only the studies focused on humans included clinical signs of leptospirosis and there is only one study that analyzes the presence of Leptospira spp. in water or soil as a risk factor for pathogen transmission. Finally, only one study investigated Leptospira in horses. Conclusion: Since sentinel species can provide useful data on infectious diseases when epidemiologic al information is lacking, and horses could be considered excellent sentinel species to reveal circulating serovars, we propose developing a nationwide surveillance system using horses. This cost-effective epidemiological survey method provides a baseline for implementing specific prevention and control programs in Ecuador and neighboring developing countries.

Fast Parabolic Fitting: An R-Peak Detection Algorithm for Wearable ECG Devices.

Heart diseases rank among the most fatal health concerns globally, with the majority being preventable through early diagnosis and effective treatment. Electrocardiogram (ECG) analysis is critical in detecting heart diseases, as it captures the heart's electrical activities. For continuous monitoring, wearable electrocardiographic devices must ensure user comfort over extended periods, typically 24 to 48 h. These devices demand specialized algorithms with low computational complexity to accommodate memory and power consumption constraints. One of the most crucial aspects of ECG signals is accurately detecting heartbeat intervals, specifically the R peaks. In this study, we introduce a novel algorithm designed for wearable devices, offering two primary attributes: robustness against noise and low computational complexity. Our algorithm entails fitting a least-squares parabola to the ECG signal and adaptively shaping it as it sweeps through the signal. Notably, our proposed algorithm eliminates the need for band-pass filters, which can inadvertently smooth the R peaks, making them more challenging to identify. We compared the algorithm's performance using two extensive databases: the meta-database QT database and the BIH-MIT database. Importantly, our method does not necessitate the precise localization of the ECG signal's isoelectric line, contributing to its low computational complexity. In the analysis of the QT database, our algorithm demonstrated a substantial advantage over the classical Pan-Tompkins algorithm and maintained competitiveness with state-of-the-art approaches. In the case of the BIH-MIT database, the performance results were more conservative; they continued to underscore the real-world utility of our algorithm in clinical contexts.

Effect of 24-h blood pressure dysregulations and reduced ocular perfusion pressure in open-angle glaucoma progression.

BACKGROUND: Low ocular perfusion pressure (OPP), which depends on the mean arterial pressure (MAP) and intraocular pressure (IOP), is associated with glaucoma. We studied 24-h MAP dysregulations and OPP in relation to the progression of glaucoma damage. METHODS: We retrospectively analyzed 155 normal-tension glaucoma (NTG) and 110 primary open-angle glaucoma (POAG) patients aged 18 years old followed at the University Hospital Leuven with repeated visual field tests ( n  = 7000 measures, including both eyes) who underwent 24-h ambulatory blood pressure monitoring. Twenty-four-hour MAP dysregulations were variability independent of the mean (VIM), and the five lowest dips in MAP readings over 24 h. OPP was the difference between 2/3 of the MAP and IOP. Glaucoma progression was the deterioration of the visual field, expressed as decibel (dB) changes in mean deviation analyzed by applying multivariable linear mixed regression models. RESULTS: The mean age was 68 years (53% were women). High 24-h VIMmap was associated with glaucoma progression in POAG ( P  < 0.001) independently of the 24-h MAP level. The estimated changes in mean deviation in relation to dip MAP measures ranged from -2.84 dB [95% confidence interval (CI) -4.12 to -1.57] to -2.16 dB (95% CI -3.46 to -0.85) in POAG. Reduced OPP along with high variability and dips in MAP resulted in worse mean deviation deterioration. CONCLUSION: The progression of glaucoma damage associates with repetitive and extreme dips in MAP caused by high variability in MAP throughout 24 h. This progression exacerbates if 24-h MAP dysregulations occur along with reduced OPP.

Propensity score matching analysis of laparoscopic surgery vs. open approach in 4 297 adult patients with acute appendicitis, acute cholecystitis or gastrointestinal tract perforation: a prospective multicentre study of nationwide outcomes.

BACKGROUND AND AIMS: Previous studies indicated that laparoscopic surgery could improve postoperative outcomes in acute appendicitis, acute cholecystitis, perforated gastroduodenal ulcer, or acute diverticulitis, but some reported opposite results or differences in the magnitude of improvement. A contemporary analysis using propensity score matching that compares outcomes is lacking. METHODS: Over a 6-month period, 38 centres (5% of all public hospitals) attending emergency general surgery patients on a 24 h, 7 days a week basis, enroled all consecutive adult patients who underwent laparoscopic surgery or open approach. RESULTS: The study included 2 645 patients with acute appendicitis [32 years (22-51), 44.3% women], 1 182 with acute cholecystitis [65 years (48-76); 46.7% women], and 470 with gastrointestinal tract perforation [65 years (50-76); 34% women]. After propensity score matching, hospital stays decreased in acute appendicitis [open, 2 days (2-4); lap, 2 days (1-4); P <0.001], acute cholecystitis [open, 7 days (4-12); lap, 4 days (3-6); P <0.001], and gastrointestinal tract perforation [open, 11 days (7-17); lap, 6 days (5-8.5); P <0.001]. A decrease in 30-day morbidity was observed in acute appendicitis (open, 15.7%; lap, 9.7%; P <0.001), acute cholecystitis (open, 41%; lap, 21.7%; P <0.001), and gastrointestinal tract perforation (open, 45.2%; lap, 23.5%; P <0.001). A decrease in 30-day mortality was found in acute cholecystitis (open, 8.8%; lap, 2.8%; P =0.013) and gastrointestinal tract perforation (open, 10.4%; lap, 1.7%; P =0.013). CONCLUSIONS: This clinically based, multicentre study suggests that an initial laparoscopic approach could be considered not only in patients with acute appendicitis or acute cholecystitis but also in patients with a perforation of the gastrointestinal tract.

NT-proBNP, cerebral small vessel disease and cardiac function in patients with a recent lacunar infarct.

NT-proBNP is produced from both atria and ventricles and it is increased in patients with cardiac disease. NT-proBNP is also associated with cerebral small vessel disease(cSVD) but there are no studies that had carried out a systematic evaluation of cardiac function in this specific setting. We conducted a prospective observational study in 100 patients within 30 days after a recent lacunar infarct by means of brain MRI, 24 h ambulatory blood pressure monitoring, transthoracic echocardiography, and plasmatic NT-proBNP. Global cSVD burden was quantified using a validated visual score (0 to 4) and dichotomized into 2 groups (0-2 or 3-4). Age (73.8 vs 63.5 years) and NT-proBNP (156 vs 76 pg/ml) were increased in patients with SVD 3-4, while daytime augmentation index normalized for the heart rate of 75 bpm (AIx75) (22.5 vs 25.6%) was decreased. The proportion of patients with left atrial enlargement, left ventricular hypertrophy, or septal e' velocity <7 cm/s was not different between both groups. NT-proBNP was increased in patients with left atrial enlargement (126 vs 88 pg/ml). In multivariate analysis, age (OR 1.129 CI 95% 1.054-1.209), daytime AIx75 (OR 0.91 CI 95% 0.84-0.987,) and NT-proBNP (OR 1.007 CI 95% 1.001-1.012,) were independently associated with cSVD score 3-4. In conclusion, as well as in other patients with cSVD we found an association between NT-proBNP and cSVD. This association was independent of cardiac function.

Progression of functional and structural glaucomatous damage in relation to diurnal and nocturnal dips in mean arterial pressure.

Background: Systemic hypoperfusion plays a pivotal role in the pathogenesis of primary open-angle glaucoma (POAG). Extreme dips in mean arterial pressure (MAP) due to high 24-h variability are associated with POAG, however, whether this is driven by diurnal or nocturnal dips remains undocumented. We aimed this study to investigate the association of POAG damage with variability and dips in the diurnal and nocturnal MAP. Methods: We conducted a retrospective longitudinal study that included 110 POAG patients who underwent 24-h ambulatory blood pressure monitoring. Our outcomes included (i) functional [visual field defects expressed as mean deviation (MD)] and (ii) structural (optic disc cupping obtained from cup-to-disc ratio) glaucoma damage. MAP variability independent of the mean (VIMmap) was computed for diurnal and nocturnal MAP. Dips were the five diurnal and three nocturnal lowest drops in MAP. We also calculated the night-to-day ratio. We applied mixed models to evaluate the progression of visual field defects and optic disc cupping in relation to diurnal and nocturnal MAP measures. Results: The mean age was 64.0 y (53% women). The median follow-up was 9 years. In adjusted mixed models, functional progression of glaucoma damage was associated with VIMmap (-2.57 dB change in MD per every 3 mmHg increase in VIMmap; P < 0.001) and diurnal MAP dips (changes in the MD ranged from -2.56 to -3.19 dB; P < 0.001). Every 5 mmHg decrease in the nocturnal MAP level was associated with -1.14 dB changes in MD [95% confidence interval (CI), -1.90 to -0.40] and 0.01 larger optic disc cupping (95% CI, 0.01-0.02). Lower night-to-day ratio was also related to both outcomes (P ≤ 0.012). Functional glaucoma damage worsened if nocturnal hypotension was combined with high variability or extreme dips in the diurnal MAP (P ≤ 0.022). Conclusion: Progression of glaucoma damage in POAG associates with high variability and extreme dips in the diurnal MAP. Structural glaucoma damage seems more vulnerable to nocturnal hypotension. Ambulatory blood pressure monitoring allows the assessment of sporadic diurnal and persistent nocturnal hypotension episodes. These phenotypes might offer an opportunity to improve the risk-stratification of open-angle glaucoma (OAG).

Abordaje transcaval en reemplazo valvular aórtico percutáneo: primer caso en Costa Rica / Transcaval approach in valve replacement Percutaneous Aortic Surgery: First Case in Costa Rica

La estenosis aórtica severa sintomática que se presenta en pacientes de alto o mediano riesgo quirúrgico puede ser abordada de manera percutánea con reemplazos valvulares aórticos transcateter. Existe sólida evidencia de resultados favorables en estos pacientes con un perfil de seguridad adecuado. El abordaje transfemoral es el más utilizado y ha demostrado ser más seguro en comparación a los abordajes torácicos. Sin embargo, desde mitades de la década pasada el abordaje transcaval se ha convertido en una opción en los pacientes que presentan un riesgo quirúrgico alto y que presentan una vasculatura inadecuada para un abordaje transfemoral seguro. Presentamos el caso de un paciente de 65 años en quien se empleó este abordaje dado a su alto riesgo quirúrgico e inaccesibilidad para realizar un abordaje transfemoral.

Severe symptomatic aortic stenosis in patients with high surgical risk can be addressed percutaneously with transcatheter aortic valve replacement (TAVR). There is solid evidence of favorable results with an adequate safety profile in these patients. The transfemoral approach is the most widely used and has shown to be safer compared to thoracic approaches. Though, since the middle of the last decade, the transcaval approach has become an option in patients who present a high surgical risk and who have inadequate vasculature for a safe transfemoral approach. We present the case of a 65-year-old patient in whom this approach was preferred due to his high surgical risk and inaccessibility to perform a transfemoral approach.

Determinants and Trends of the Use of Intravenous Thrombolysis for Minor Stroke: A Population-Based Study, 2016 to 2020.

BACKGROUND: We analyzed the main factors associated with intravenous thrombolysis (IVT) in patients with minor ischemic stroke. METHODS: Data were obtained from a prospective, government-mandated, population-based registry of stroke code patients in Catalonia (6 Comprehensive Stroke Centers, 8 Primary Stroke Centers, and 14 TeleStroke Centers). We selected patients diagnosed with ischemic stroke and National Institutes of Health Stroke Scale (NIHSS) ≤5 at hospital admission from January 2016 to December 2020. We excluded patients with a baseline modified Rankin Scale score of ≥3, absolute contraindication for IVT, unknown stroke onset, or admitted to hospital beyond 4.5 after stroke onset. The main outcome was treatment with IVT. We performed univariable and binary logistic regression analyses to identify the most important factors associated with IVT. RESULTS: We included 2975 code strokes; 1433 (48.2%) received IVT of which 30 (2.1%) had a symptomatic hemorrhagic transformation. Patients treated with IVT as compared to patients who did not receive IVT were more frequently women, had higher NIHSS, arrived earlier to hospital, were admitted to a Comprehensive Stroke Centers, and had large vessel occlusion. After binary logistic regression, NIHSS score 4 to 5 (odds ratio, 40.62 [95% CI, 31.73-57.22]; P<0.001) and large vessel occlusion (odds ratio, 16.39 [95% CI, 7.25-37.04]; P<0.001) were the strongest predictors of IVT. Younger age, female sex, baseline modified Rankin Scale score of 0, earlier arrival to hospital (<120 minutes after stroke onset), and the type of stroke center were also independently associated with IVT. The weight of large vessel occlusion on IVT was higher in patients with lower NIHSS. CONCLUSIONS: Minor stroke female patients, with higher NIHSS, arriving earlier to the hospital, presenting with large vessel occlusion and admitted to a Comprehensive Stroke Centers were more likely to receive intravenous thrombolysis.

Subclinical Magnetic Resonance Imaging Markers of Cerebral Small Vessel Disease in Relation to Office and Ambulatory Blood Pressure Measurements.

Background: Twenty-four-hour and nighttime blood pressure (BP) levels are more strongly associated with cardiovascular risk than office or daytime BP measurements. However, it remains undocumented which of the office and ambulatory BP measurements have the strongest association and predictive information in relation to the presence of type I, or arteriolosclerosis type, cerebral small vessel diseases (CSVD). Methods: A subset of 429 participants from the Maracaibo Aging Study [aged ≥40 years (women, 73.7%; mean age, 59.3 years)] underwent baseline brain magnetic resonance imaging (MRI) to visualize CSVD, which included log-transformed white matter hyperintensities (log-WMH) volume and the presence (yes/no) of lacunes, cerebral microbleeds (CMB), or enlarged perivascular spaces (EPVS). Linear and logistic regression models were applied to examine the association between CSVD and each +10-mmHg increment in the office and ambulatory systolic BP measurements. Improvement in the fit of nested logistic models was assessed by the log-likelihood ratio and the generalized R 2 statistic. Results: Office and ambulatory systolic BP measurements were related to log-WMH (ß-correlation coefficients ≥0.08; P < 0.001). Lacunes and CMB were only associated with ambulatory systolic BP measurements (odds ratios [OR] ranged from 1.31 [95% confidence interval, 1.10-1.55] to 1.46 [1.17-1.84], P ≤ 0.003). Accounted for daytime systolic BP, both the 24-h (ß-correlation, 0.170) and nighttime (ß-correlation, 0.038) systolic BP measurements remained related to log-WMH. When accounted for 24-h or daytime systolic BP levels, the nighttime systolic BP retained the significant association with lacunes (ORs, 1.05-1.06; 95% CIs, ≥1.01 to ≤ 1.13), whereas the 24-h and daytime systolic BP levels were not associated with lacunes after adjustments for nighttime systolic BP (ORs, ≤ 0.88; 95% CI, ≥0.77 to ≤ 1.14). On top of covariables and office systolic BP, ambulatory systolic BP measurements significantly improved model performance (1.05% ≥ R 2 ≤ 3.82%). Compared to 24-h and daytime systolic BP, nighttime systolic BP had the strongest improvement in the model performance; for WMH (1.46 vs. 1.05%) and lacunes (3.06 vs. ≤ 2.05%). Conclusions: Twenty-four-hour and nighttime systolic BP were the more robust BP measurements associated with CSVD, but the nighttime systolic BP level had the strongest association. Controlling ambulatory BP levels might provide additional improvement in the prevention of CSVD.

Efectividad de la reacción en cadena de la polimerasa en tiempo real (PCR-RT) e Inmunodot en el diagnóstico temprano de leptospirosis: análisis comparativo con la prueba de Microaglutinación (MAT) / Effectiveness of the real-time polymerase chain reaction (RT-PCR) and Immunodot in the early diagnosis of Leptospirosis: comparative analysis with the Microagglutination test (MAT)

Introducción: la leptospirosis es una enfermedad infecciosa producida por espiroquetas del género Leptospira. Se disemina a través de la orina de animales domésticos, con mayor frecuencia por roedores. En República Dominicana se necesitan pruebas confiables para el diagnóstico en etapas tempranas de la enfermedad. En el presente trabajo se aborda la validez diagnóstica del PCR en Tiempo Real y del IGM (INMUNODOT) en comparación con la prueba de Microaglutinación (MAT). Materiales y métodos: se realizó un estudio observacional, descriptivo, de corte transversal con 69 pacientes admitidos en el Hospital Regional "José María Cabral y Báez" con diagnóstico presuntivo de leptospirosis desde el 2010 hasta el 2012. Resultados: del total de los casos (69), la mayoría fueron del sexo masculino (94.2 %), menores de 49 años (79.4 %) y provenían de la provincia de Santiago (58 %). La mortalidad fue de 52.1 % de los cuales 52.3 % fueron reportados positivos para Leptospira y 47.6 % resultaron negativos según el MAT. Al comparar los resultados de PCR en relación al MAT se obtuvo una sensibilidad de 27.3 % y una especificidad de 80 %. Los resultados del PCR y del Immunodot fueron equivalentes. Conclusión: en el presente trabajo la realización del PCR en sangre, después del 5to día de inicio de la enfermedad, no demostró ser mejor que la Inmunodot para la detección temprana de la enfermedad, al contrastarlos con el resultado del MAT. En República Dominicana, los casos hospitalizados con diagnóstico presuntivo de leptospirosis permanecen con muy alta mortalidad. Por tanto, es prioritario optimizar el diagnóstico y el tratamiento de estos casos. En este estudio, los casos confirmados con Leptospirosis que fallecieron indican que debe actualizarse el protocolo de tratamiento y asegurarse que pueda implementarse. Por otra parte, los casos no confirmados fallecidos exigen investigar otras causas de enfermedad como la Infección por Hanta Virus.

Introduction: Leptospirosis is an infectious disease caused by spirochaetes of the genus Leptospira. It spread through the urine of domestic animals most frequently in rodents. Need reliable tests to diagnose in early stages of the disease and it has been proposed the use of the PCR in real-time as an option. The present work deals with the diagnostic real-time PCR and IGM (INMUNODOT) in comparison with the Microagglutination (MAT) test. Materials and methods: An observational, descriptive, cross-sectional study with 69 patients admitted as possible Leptospirosis in the Hospital "Jose Maria Cabral y Báez" of Santiago from 2010 to 2012. Results: Of the total cases (69), most were male (94.2%), under 49 years of age (79.4%) coming from the province of Santiago (58%). Mortality was 52.1% of which 52.3% were reported positive for leptospirosis and 47.6% were negative according to the MAT. To compare the results of PCR in relation to the MAT was obtained a sensitivity of 27.3% and a specificity of 80%. The results of the PCR and immunodot were equivalent. Conclusion: In this study, the realization of the PCR in blood after the 5th day of the disease not proved to be better than the Inmunodot for the early detection of the disease. Is necessary to evaluate cases less than 5th day. In the Dominican Republic, hospitalized with a presumptive diagnosis of Leptospirosis cases remain with very high mortality. Therefore, it is important to optimize the diagnosis and treatment of these cases. In this study, confirmed cases with Leptospirosis who died, indicate that you must upgrade the treatment protocol and ensure that it can be implemented. On the other hand, the deceased not confirmed cases require to investigate other causes of disease as the Hanta Virus infection.

A Novel Framework for Generating Personalized Network Datasets for NIDS Based on Traffic Aggregation.

In this paper, we addressed the problem of dataset scarcity for the task of network intrusion detection. Our main contribution was to develop a framework that provides a complete process for generating network traffic datasets based on the aggregation of real network traces. In addition, we proposed a set of tools for attribute extraction and labeling of traffic sessions. A new dataset with botnet network traffic was generated by the framework to assess our proposed method with machine learning algorithms suitable for unbalanced data. The performance of the classifiers was evaluated in terms of macro-averages of F1-score (0.97) and the Matthews Correlation Coefficient (0.94), showing a good overall performance average.

Open-Angle Glaucomatous Optic Neuropathy Is Related to Dips Rather Than Increases in the Mean Arterial Pressure Over 24-H.

BACKGROUND: Mean arterial pressure (MAP) drives ocular perfusion. Excessive 24-h MAP variability relates to glaucoma, however, whether this is due to dips or increases in the blood pressure (BP) is undocumented. We investigated the association of open-angle glaucoma (OAG) in relation to the 5 largest MAP dips/increases over 24-h, henceforth called dips/blips. METHODS: In the Maracaibo Aging Study (MAS), 93 participants aged ≥40 y (women, 87.1%; mean age, 61.9 y) underwent baseline ophthalmological and 24-h ambulatory BP monitoring assessments. OAG was the presence of optic nerve damage and visual field defects. Statistical methods included logistic regression and the generalized R2 statistic. For replication, 48 OAG cases at the Leuven Glaucoma Clinic were matched with 48 controls recruited from Flemish population. RESULTS: In the MAS, 26 participants had OAG. OAG compared to non-OAG participants experienced longer and deeper dips (116.5 vs. 102.7 minutes; to 60.3 vs. 66.6 mm Hg; -21.0 vs. -18.0 mm Hg absolute or 0.79 vs. 0.81 relative dip compared to the preceding reading). The adjusted odds ratios associated with dip measures ranged from 2.25 (95% confidence interval [CI], 1.31-4.85; P = 0.009) to 3.39 (95% CI, 1.36-8.46; P = 0.008). On top of covariables and 24-MAP level/variability, the dip measures increased the model performance (P ≤ 0.025). Blips did not associate with OAG. The case-control study replicated the MAS observations. CONCLUSIONS: Dips rather than increases in the 24-h MAP level were associated with increased risk for OAG. An ophthalmological examination combined with 24-h BP monitoring might be precautious steps required in normotensive and hypertensive patients at risk of OAG.

Impact of COVID-19 Infection on the Outcome of Patients With Ischemic Stroke.

BACKGROUND AND PURPOSE: We evaluated whether stroke severity, functional outcome, and mortality are different in patients with ischemic stroke with or without coronavirus disease 2019 (COVID-19) infection. METHODS: A prospective, observational, multicentre cohort study in Catalonia, Spain. Recruitment was consecutive from mid-March to mid-May 2020. Patients had an acute ischemic stroke within 48 hours and a previous modified Rankin Scale (mRS) score of 0 to 3. We collected demographic data, vascular risk factors, prior mRS score, National Institutes of Health Stroke Scale score, rate of reperfusion therapies, logistics, and metrics. Primary end point was functional outcome at 3 months. Favourable outcome was defined depending on the previous mRS score. Secondary outcome was mortality at 3 months. We performed mRS shift and multivariable analyses. RESULTS: We evaluated 701 patients (mean age 72.3±13.3 years, 60.5% men) and 91 (13%) had COVID-19 infection. Median baseline National Institutes of Health Stroke Scale score was higher in patients with COVID-19 compared with patients without COVID-19 (8 [3-18] versus 6 [2-14], P=0.049). Proportion of patients with a favourable functional outcome was 33.7% in the COVID-19 and 47% in the non-COVID-19 group. However, after a multivariable logistic regression analysis, COVID-19 infection did not increase the probability of unfavourable functional outcome. Mortality rate was 39.3% among patients with COVID-19 and 16.1% in the non-COVID-19 group. In the multivariable logistic regression analysis, COVID-19 infection was a risk factor for mortality (hazard ratio, 3.14 [95% CI, 2.10-4.71]; P<0.001). CONCLUSIONS: Patients with ischemic stroke and COVID-19 infection have more severe strokes and a higher mortality than patients with stroke without COVID-19 infection. However, functional outcome is comparable in both groups.

Normal-tension glaucomatous optic neuropathy is related to blood pressure variability in the Maracaibo Aging Study.

Hypoperfusion of the optic nerve might be involved in the pathogenesis of normal-tension glaucomatous optic neuropathy (GON). Mean arterial pressure (MAP) drives ocular perfusion, but no previous studies have addressed the risk of GON in relation to blood pressure (BP) variability, independent of BP level. In a cross-sectional study, 93 residents of Maracaibo, Venezuela, underwent optical coherence tomography, visual field assessments and 24-h ambulatory BP monitoring between 2011 and 2016. We investigated the association of normal-tension GON with or without visual field defects with reading-to reading variability of 24-h MAP, as captured by variability independent of the MAP level (VIMmap). Odds ratios (ORs) were adjusted for 24-h MAP level and for a propensity score of up to five risk factors. Among the 93 participants (87.1% women; mean age, 61.9 years), 26 had open-angle normal-tension GON at both eyes; 14 had visual field defects; and 19 did not have visual field defects. The OR ratios for normal-tension GON, expressed per 1-SD increment in VIMmap (2 mm Hg), were 2.17 (95% confidence interval, 1.33-3.53) unadjusted; 2.20 (1.35-3.61) adjusted for 24-h MAP level only; 1.93 (1.10-3.41) with additional adjustment for age, educational attainment, high-density lipoprotein (HDL) cholesterol and office hypertension; and 1.95 (1.10-3.45) in models including intraocular pressure. We confirmed our a priori hypothesis that BP variability, most likely operating via hypoperfusion of the optic nerve, is associated with normal-tension GON. 24-H ambulatory BP monitoring might therefore help stratify the risk of normal-tension GON.

Higher Cerebral Small Vessel Disease Burden in Patients with White Matter Recent Small Subcortical Infarcts.

INTRODUCTION: Recent small subcortical infarcts (RSSI) are considered an acute manifestation of cerebral small vessel disease (CSVD). We assessed whether the topography of RSSI was related to CSVD markers on magnetic resonance imaging (MRI). MATERIAL AND METHODS: We screened the local registries of two independent stroke centers in Catalonia and selected patients with a symptomatic RSSI on MRI performed during admission. RSSI location was classified into brainstem, supratentorial subcortical structures (SSS), and centrum semiovale (CSO) regions. Clinical variables, including vascular risk factors, were collected. Radiological markers of CSVD on MRI were evaluated individually and by means of the global CSVD burden score. The associations between each RSSI location and CSVD markers were studied in uni- and multivariate logistic regression analysis. RESULTS: Among 475 patients with RSSI, 152 (32%) had an infarct in the brainstem, 227 (48%) in SSS, and 96 (20%) in CSO region. The median CSVD burden score was 2 (IQR, 1-3). After adjusting for confounding factors, a RSSI in CSO was associated with higher periventricular and deep white matter hyperintensity scores [OR 1.64 (95% CI, 1.16-2.33), and OR 1.44 (95% CI, 1.07-1.93), respectively]. Higher CSVD burden score was positively associated with CSO [OR 1.48 (95% CI, 1.22-1.81)] and inversely associated with SSS [0.85 (95% CI, 0.72-0.99)] location after adjusting for relevant confounders. CONCLUSIONS: CSO RSSI were related to a higher burden of CSVD, particularly to white matter hyperintensities, compared to other RSSI locations. The pathophysiological significance of such findings should be investigated in the future with advanced neuroimaging techniques.

Machine learning for guiding high-temperature PEM fuel cells with greater power density.

High-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) are enticing energy conversion technologies because they use low-cost hydrogen generated from methane and have simple water and heat management. However, proliferation of this technology requires improvement in power density. Here, we show that Machine Learning (ML) tools can help guide activities for improving HT-PEMFC power density because these tools quickly and efficiently explore large search spaces. The ML scheme relied on a 0-D, semi-empirical model of HT-PEMFC polarization behavior and a data analysis framework. Existing datasets underwent support vector regression analysis using a radial basis function kernel. In addition, the 0-D, semi-empirical HT-PEMFC model was substantiated by polarization data, and synthetic data generated from this model was subject to dimension reduction and density-based clustering. From these analyses, pathways were revealed to surpass 1 W cm-2 in HT-PEMFCs with oxygen as the oxidant and CO containing hydrogen.

Research on aging during the Venezuelan humanitarian crisis: the experience of the Maracaibo aging study.

BACKGROUND: Venezuela is in the throes of a complex humanitarian crisis that is one of the worst in decades to impact any country outside of wartime. This case analysis describes the challenges faced by the ongoing Maracaibo Aging Study (MAS) during the deteriorating conditions in Venezuela. When the MAS began in 1997, it focused on memory-related disorders. Since then, strategic planning and proactive community participation allowed us to anticipate and address logistical, funding, and ethical challenges, and facilitated the enrollment and retention of more than 2500 subjects over 55 years of age. All participants, who are residents of the city of Maracaibo, Venezuela, underwent various assessments on several occasions. Here, we discuss how our approach to implementing a longitudinal, population-based study of age-related conditions has allowed our research program to continue throughout this period of political, economic, and social upheaval. DISCUSSION: As the social context in Venezuela became more complicated, new challenges emerged, and strategies to sustain the study and participation were refined. We identified five main mechanisms through which the evolving humanitarian crisis has affected implementation of the MAS: 1) community dynamics; 2) morale of researchers, staff, and participants; 3) financial feasibility; 4) components of the research process; and 5) impact on the health of staff, participants, and their families. Strategies to compensate for the impact on these components were implemented, based on inputs from community members and staff. Improved communication, greater involvement of stakeholders, broadening the scope of the project, and strengthening international collaboration have been the most useful strategies. Particular demands emerged, related to the increased mortality and comorbidities of participants and staff, and deterioration of basic services and safety. CONCLUSION: Although the MAS has faced numerous obstacles, it has been possible to continue a longitudinal research project throughout the humanitarian crisis, because our research team has engaged the community deeply and developed a sense of mutual commitment, and also because our project has provided funding to help keep researchers employed, somewhat attenuating the brain drain.