ROC curve analysis: a useful statistic multi-tool in the research of nephrology.

In the past decade, scientific research in the area of Nephrology has focused on evaluating the clinical utility and performance of various biomarkers for diagnosis, risk stratification and prognosis. Before implementing a biomarker in everyday clinical practice for screening a specific disease context, specific statistic measures are necessary to evaluate the diagnostic accuracy and performance of this biomarker. Receiver Operating Characteristic (ROC) Curve analysis is an important statistical method used to estimate the discriminatory performance of a novel diagnostic test, identify the optimal cut-off value for a test that maximizes sensitivity and specificity, and evaluate the predictive value of a certain biomarker or risk, prediction score. Herein, through practical examples, we aim to present a simple methodological approach to explain in detail the principles and applications of ROC curve analysis in the field of nephrology pertaining diagnosis and prognosis.

Diuretics or ultrafiltration in the treatment of acute decompensated heart failure: An updated systematic review and meta-analysis.

INTRODUCTION: Hospitalization for decompensated heart failure is a major public health issue. METHODS: We performed a meta-analysis to summarize and analyze if there is a benefit in using ultrafiltration over diuretics in terms of reducing mortality or hospital readmissions, primarily and identified 10 randomized controlled trials (RCTs) including 941 patients. RESULTS: Compared to diuretics, treatment with ultrafiltration was associated with a significant reduction in heart failure hospitalizations (risk ratio [RR]: 0.72; 95% confidence interval [CI]: 0.55-0.96, p = 0.02) and significant increase in weight and net fluid loss (mean difference [MD]: -1.55, CI: -2.36 to -0.74, p = 0.0002) and (MD: -2.10, CI: -3.32 to -0.89, p = 0.0007), respectively. There was no significant difference among treatments regarding the duration of hospitalization, the increase in serum creatinine levels, and mortality. CONCLUSION: Among patients with decompensated heart failure, compared to diuretics, ultrafiltration is associated with reduced rehospitalizations and increased weight/net fluid loss.

Right Ventricular Global Longitudinal Strain and Short-Term Prognosis in Patients With First Acute Myocardial Infarction.

Right ventricular (RV) dysfunction after acute myocardial infarction (AMI) is a recognized predictor of dismal prognosis. However, the most reliable RV index to predict mortality early after revascularization remains undetermined. This study aimed to explore the ability of RV global longitudinal strain (GLS) to predict inhospital mortality in patients with first AMI. All consecutive patients with first AMI were prospectively enrolled from March 2022 until February 2023. An echocardiogram was performed 24 hours after successful revascularization and RV GLS alongside conventional echocardiographic indexes were measured. Inhospital mortality was recorded. A total of 300 patients (age 61.2 ± 11.8 years, 74% male) were included in the study. RV GLS was the only RV performance index that differed significantly between anterior and inferior ST-segment-elevation patients with AMI (14.5 ± 5.2% vs 17.4 ± 5.1% respectively, p <0.001). After revascularization, 23 patients (7.7%) died in hospital. The model of Global Registry of Acute Coronary Event risk score and left ventricular ejection fraction, built for predicting inhospital mortality, significantly improved its prognostic performance only by the addition of RV GLS (chi-square value increase by 7.485, p = 0.006) compared with the other RV function indexes. RV GLS was independently associated with inhospital mortality (odds ratio 0.83, 95% confidence interval 0.71 to 0.97, p = 0.017) after adjustment for Global Registry of Acute Coronary Event risk score and left ventricular ejection fraction. Echocardiographic RV GLS measured 24 hours after revascularization in patients with first AMI outperformed conventional RV function indexes in predicting inhospital mortality.

Transcatheter Aortic Valve Implantation with the Portico Valve: 2-Year Outcomes of a Multicenter, Real-World Registry.

INTRODUCTION: The self-expanding, resheathable, repositionable transcatheter aortic heart valve Portico is being used successfully for transcatheter aortic valve implantation procedures (TAVI) in patients with severe aortic stenosis. The aim of this study was to evaluate outcomes at 2 years after TAVI with the Portico valve. METHODS: Multicenter registry of clinical, echocardiographic and survival data from consecutive patients treated with the Portico TAVI system (Abbott, Chicago, IL, USA) in three cath labs in Northern Greece and Epirus during 2017-2020. The primary end point was all-cause mortality at 24 months. Secondary end points included procedural outcomes (efficacy and safety) and echocardiographic measurements. RESULTS: A total of 90 patients (81 ± 6 years, 50% females, mean age 81 ± 6 years) were included in the registry. The indication for implantation was severe, symptomatic aortic stenosis (NYHA III, IV) in eighty-two (91.1%) and degeneration of a prosthetic aortic valve in eight (8.9%) patients. All patients were categorized as high surgical risk (mean Logistic Euroscore 25.9 ± 10, Euroscore II 7.7 ± 4.4 and STS score 10.8 ± 8.9). The procedure was performed transfemorally in all patients, under general anesthesia in 95.6%, under TOE guidance in 21.1%, with native valve predilatation in 46.7%, and the "resheath" option was used in 31.1% of the cases. The implantation was successful in 97.8% and there was a need for a second valve in 2.2% of the cases. Complications included permanent pacemaker implantation (16.7%), access cite complications (15.6%), arrythmias (23.3%), paravalvular leak (moderate 7.8%, severe 1.1%), acute kidney injury (7.8%), no strokes and one death during the procedure. Aortic valve peak velocity, peak and mean pressure gradients, were significantly reduced after the procedure. All-cause mortality at 1, 12 and 24 months was 4.4%, 6.7% and 7.8%, respectively. CONCLUSIONS: TAVI with the Portico system comprises an effective and safe solution for the management of severe, symptomatic aortic stenosis in high-risk surgical patients.

Apical Hypertrophic Cardiomyopathy: Diagnosis, Natural History, and Management.

Apical hypertrophic cardiomyopathy (ApHCM) represents a rare variant of hypertrophic cardiomyopathy (HCM) with distinct phenotypic characteristics. The prevalence of this variant varies according to each study's geographic region. The leading imaging modality for the diagnosis of ApHCM is echocardiography. Cardiac magnetic resonance, however, is the gold standard for ApHCM diagnosis in case of poor acoustic windows or equivocal echocardiographic findings but also in cases of suspected apical aneurysms. The prognosis of ApHCM was reported to be relatively benign, although more recent studies seem to contradict this, demonstrating similar incidence of adverse events compared with the general HCM population. The aim of this review is to summarize the available evidence for the diagnosis of ApHCM, highlight distinctions in comparison to more frequent forms of HCM with regards to its natural history, prognosis, and management strategies.

Modelling the COVID-19 pandemic: Focusing on the case of Greece.

The SARS-CoV-2 infection (COVID-19) pandemic created an unprecedented chain of events at a global scale, with European counties initially following individual pathways on the confrontation of the global healthcare crisis, before organizing coordinated public vaccination campaigns, when proper vaccines became available. In the meantime, the viral infection outbreaks were determined by the inability of the immune system to retain a long-lasting protection as well as the appearance of SARS-CoV-2 variants with differential transmissibility and virulence. How do these different parameters regulate the domestic impact of the viral epidemic outbreak? We developed two versions of a mathematical model, an original and a revised one, able to capture multiple factors affecting the epidemic dynamics. We tested the original one on five European countries with different characteristics, and the revised one in one of them, Greece. For the development of the model, we used a modified version of the classical SEIR model, introducing various parameters related to the estimated epidemiology of the pathogen, governmental and societal responses, and the concept of quarantine. We estimated the temporal trajectories of the identified and overall active cases for Cyprus, Germany, Greece, Italy and Sweden, for the first 250 days. Finally, using the revised model, we estimated the temporal trajectories of the identified and overall active cases for Greece, for the duration of the 1230 days (until June 2023). As shown by the model, small initial numbers of exposed individuals are enough to threaten a large percentage of the population. This created an important political dilemma in most countries. Force the virus to extinction with extremely long and restrictive measures or merely delay its spread and aim for herd immunity. Most countries chose the former, which enabled the healthcare systems to absorb the societal pressure, caused by the increased numbers of patients, requiring hospitalization and intensive care.

The prognostic value of right ventricular longitudinal strain in heart failure: a systematic review and meta-analysis.

BACKGROUND: Right ventricular (RV) dysfunction is a well-recognized adverse prognostic feature in patients with heart failure (HF). Recently, many single-center studies have demonstrated that RV longitudinal strain assessed using speckle tracking echocardiography might be a powerful prognosticator in HF. OBJECTIVES: To systematically appraise and quantitatively synthesize the evidence of the prognostic value of echocardiographic RV longitudinal strain, across the entire spectrum of left ventricular ejection function (LVEF) in HF. METHODS: A systematic literature review was conducted in electronic databases to identify every study reporting the predictive role of RV global longitudinal strain (RV GLS) and RV free wall longitudinal strain (RV FWLS) in HF subjects. A random-effects meta-analysis was conducted to quantify the adjusted and unadjusted hazard ratios [(a)HRs] for all-cause-mortality and for the composite outcome of all-cause mortality or HF-related hospitalization for both indices. RESULTS: Twenty-four studies were deemed eligible and 15 of these provided appropriate quantitative data for the meta-analysis, encompassing 8,738 patients. Each 1% worsening in RV GLS and RV FWLS was independently associated with increased risk of all-cause mortality (pooled aHR = 1.08 [1.03-1.13]; p < 0.01; I2 = 76% and 1.05 [1.05-1.06]; p < 0.01; I2 = 0%, respectively) and the composite outcome (pooled aHR = 1.10 [1.06-1.15]; p < 0.01; I2 = 0% and 1.06 [1.02-1.10]; p < 0.01; I2 = 69%, respectively) for patients with HF. The subgroup analysis of HF patients with LVEF < 45% yielded similar results, with worsening in RV GLS and RV FWLS retaining strong association with the two outcomes. CONCLUSION: Echocardiographic RV GLS and RV FWLS appear to have powerful prognostic value across the range of HF.

Measures of frequency and effect in clinical research.

The assessment of risk and effect size of a specific endpoint associated to the presence/absence of a certain exposure is a hallmark in clinical and epidemiological research. In fact, before recommending any treatment, it is mandatory to investigate the magnitude of the benefits and harms between the exposure under investigation (e.g. a given treatment) and a specific disease or event. To do this, clinicians and statisticians use absolute (risk differences, number needed to treat, likelihood to be helped or harmed) and relative (risk ratio, incidence rate ratio, hazard ratio and odds ratio) measures of effect. Herein, using a series of clinical examples, we aim to present a step by step methodologic approach of measures of effect in the area of nephrology and urology.

Variant-Related Differences in Laboratory Biomarkers among Patients Affected with Alpha, Delta and Omicron: A Retrospective Whole Viral Genome Sequencing and Hospital-Setting Cohort Study.

During the COVID-19 pandemic, different SARS-CoV-2 variants of concern (VOC) with specific characteristics have emerged and spread worldwide. At the same time, clinicians routinely evaluate the results of certain blood tests upon patient admission as well as during hospitalization to assess disease severity and the overall patient status. In the present study, we searched for significant cell blood count and biomarker differences among patients affected with the Alpha, Delta and Omicron VOCs at admission. Data from 330 patients were retrieved regarding age, gender, VOC, cell blood count results (WBC, Neut%, Lymph%, Ig%, PLT), common biomarkers (D-dimers, urea, creatinine, SGOT, SGPT, CRP, IL-6, suPAR), ICU admission and death. Statistical analyses were performed using ANOVA, the Kruskal-Wallis test, two-way ANOVA, Chi-square, T-test, the Mann-Whitney test and logistic regression was performed where appropriate using SPSS v.28 and STATA 14. Age and VOC were significantly associated with hospitalization, whereas significant differences among VOC groups were found for WBC, PLT, Neut%, IL-6, creatinine, CRP, D-dimers and suPAR. Our analyses showed that throughout the current pandemic, not only the SARS-CoV-2 VOCs but also the laboratory parameters that are used to evaluate the patient's status at admission are subject to changes.

Prescription Rates and Prognostic Implications of Optimally Targeted Guideline-Directed Medical Treatment in Heart Failure and Atrial Fibrillation: Insights From The MISOAC-AF Trial.

ABSTRACT: Heart failure (HF) and atrial fibrillation (AF) commonly coexist in real-life clinical practice. Among patients with HF with reduced ejection fraction (HFrEF) or HF with mildly reduced ejection fraction (HFmrEF), guidelines call for evidence-based target doses of renin-angiotensin-aldosterone system inhibitors and beta-blockers. However, target doses of guideline-directed medical treatment (GDMT) are often underused in real-world conditions, including HF-AF comorbidity. This retrospective cohort study of a randomized trial (Motivational Interviewing to Support Oral AntiCoagulation adherence in patients with nonvalvular AF) included hospitalized patients with AF and HFrEF or HFmrEF. Optimally targeted GDMT was defined as intake of evidence-based target doses of renin-angiotensin-aldosterone system and beta-blockers at 3 months after discharge. Rates of optimally targeted GDMT achievement across the baseline estimated glomerular filtration rate (eGFR) were assessed. Independent predictors of nontargeted GDMT and its association with all-cause mortality and the composite of cardiovascular death or HF hospitalization were assessed by regression analyses. In total, 374 patients with AF and HFrEF or HFmrEF were studied. At 3 months after discharge, 30.7% received target doses of GDMT medications. The rate of optimally targeted GDMT was reduced by 11% for every 10 mg/min/1.73 m 2 decrease in baseline eGFR [adjusted ß = 0.99; 95% confidence interval (CI), 0.98-0.99] levels. After a median 31-month follow-up period, 37.8% patients in the optimally targeted GDMT group died, as compared with 67.8% (adjusted hazard ratio: 1.49; 95% CI, 1.05-2.13) in the nontargeted GDMT group. The risk of cardiovascular death or HF hospitalization was also higher in these patients (adjusted hazard ratio: 1.60; 95% CI, 1.17-2.20). Target doses of all HF drugs were reached in roughly one-third of patients with AF and HFrEF or HFmrEF 3 months after hospital discharge. Nontargeted GDMT was more frequent across lower eGFR levels and was associated with worse outcomes.

Effect of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers on cardiovascular outcomes in dialysis patients: a systematic review and meta-analysis.

BACKGROUND: Angiotensin-converting enzyme inhibitors (ACEIs) and/or angiotensin receptor blockers (ARBs) are recommended by guidelines as first-line antihypertensive therapies in the general population or in patients with earlier stages of kidney disease. However, the cardioprotective benefit of these agents among patients on dialysis remains uncertain. METHODS: We searched the MEDLINE, PubMed and Cochrane databases from inception through February 2022 to identify randomized controlled trials (RCTs) comparing the efficacy of ACEIs/ARBs relative to placebo or no add-on treatment in patients receiving dialysis. RCTs were eligible if they assessed fatal or non-fatal cardiovascular events as a primary efficacy endpoint. RESULTS: We identified five RCTs involving 1582 dialysis patients. Compared with placebo or no add-on treatment, the use of ACEIs/ARBs was not associated with a significantly lower risk of cardiovascular events {risk ratio [RR] 0.79 [95% confidence interval (CI) 0.57-1.11]}. Furthermore, there was no benefit in cardiovascular mortality [RR 0.82 (95% CI 0.59-1.14)] and all-cause mortality [RR 0.86 (95% CI 0.64-1.15)]. These results were consistent when the included RCTs were stratified by subgroups, including hypertension, ethnicity, sample size, duration of follow-up and quality. CONCLUSION: The present meta-analysis showed that among patients on dialysis, the use of ACEIs/ARBs is not associated with a significantly lower risk of cardiovascular events and all-cause mortality as compared with placebo or no add-on treatment.

Hypertension in Dialysis Patients: Diagnostic Approaches and Evaluation of Epidemiology.

Whereas hypertension is an established cardiovascular risk factor in the general population, the contribution of increased blood pressure (BP) to the huge burden of cardiovascular morbidity and mortality in patients receiving dialysis continues to be debated. In a large part, this controversy is attributable to particular difficulties in the accurate diagnosis of hypertension. The reverse epidemiology of hypertension in dialysis patients is based on evidence from large cohort studies showing that routine predialysis or postdialysis BP measurements exhibit a U-shaped or J-shaped association with cardiovascular or all-cause mortality. However, substantial evidence supports the notion that home or ambulatory BP measurements are superior to dialysis-unit BP recordings in diagnosing hypertension, in detecting evidence of target-organ damage and in prognosticating the all-cause death risk. In the first part of this article, we explore the accuracy of different methods of BP measurement in diagnosing hypertension among patients on dialysis. In the second part, we describe how the epidemiology of hypertension is modified when the assessment of BP is based on dialysis-unit versus home or ambulatory recordings.

Renal function and mortality in patients with atrial fibrillation.

AIM: The aim of this study is to examine the association of the presence of chronic kidney disease (CKD) and estimated glomerular filtration rate (eGFR) values with mortality in patients with atrial fibrillation. METHODS: This posthoc analysis of a randomized controlled trial consisted of hospitalized patients with atrial fibrillation who were followed up for a median of 2.7 years after discharge. Kaplan-Meier curves, multivariate Cox-regression and spline curves were utilized to assess the association of CKD, CKD stages 2-5 according to the KDOQI guidelines, and the continuum of eGFR values with the primary outcome of all-cause death, and the secondary outcome of cardiovascular mortality. RESULTS: Out of 1064 hospitalized patients with atrial fibrillation, 465 (43.7%) had comorbid CKD. The presence of CKD was associated with an increased risk for both all-cause and cardiovascular mortality following hospitalization [adjusted hazard ratio (aHR): 1.60; 95% confidence intervals (95% CIs): 1.25-2.05 and aHR: 1.74; 95% CI: 1.30-2.33, respectively]. The aHRs for all-cause mortality in CKD stages 2-5, as compared with CKD stage 1 were 2.18, 2.62, 4.20 and 3.38, respectively (all P < 0.05). In spline curve analyses, eGFR values lower than 50 ml/min/1.73 m2 were independent predictors of higher all-cause and cardiovascular mortality. CONCLUSION: In recently hospitalized patients with atrial fibrillation, the presence of CKD was independently associated with decreased survival, which was significant across CKD stages 2-5, as compared with CKD stage 1. Values of eGFR lower than 50 ml/min/1.73 m2 were incrementally associated with worse prognosis.

Predictive Role of Platelet-Associated Indices on Admission and Discharge in the Long-Term Prognosis of Acute Coronary Syndrome Patients.

Our study aimed to investigate the association between platelet indices and their in-hospital change and long-term prognosis in acute coronary syndrome (ACS). Data from a randomized controlled trial (NCT02927808) recruiting ACS patients were analyzed (survival analysis). The examined variables were platelet count (PC), mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT) on admission and discharge, as well as their alteration during hospitalization. The primary endpoint was major adverse cardiac events (MACE) (cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke or hospitalization for unstable angina) and all-cause mortality, while secondary endpoints were all-cause hospitalization and bleeding events. The study included 252 patients with a follow-up of 39 (28-45) months. In the univariate analysis, MACE was associated with discharge PC [hazard ratio (HR) 2.20, 95% confidence interval (CI) 1.10-4.40], discharge MPV (HR 0.48, 95% CI 0.25-0.94), and in-hospital PC difference (HR 0.25, 95% CI 0.13-0.51). In the multivariable analysis, only in-hospital PC decrease correlated with lower MACE incidence (adjusted HR .27, 95% CI 0.14-0.54) and lower all-cause hospitalization risk (adjusted HR 0.36, 95% CI 0.19-0.68). PC reduction during hospitalization for ACS is an independent predictor of better prognosis.

Prognostic implications of valvular heart disease in patients with non-valvular atrial fibrillation.

BACKGROUND: Valvular heart disease (VHD) in non-valvular atrial fibrillation (AF) is a puzzling clinical entity. The aim of this study was to evaluate the prognostic effect of significant VHD (sVHD) among patients with non-valvular AF. METHODS: This is a post-hoc analysis of the MISOAC-AF trial (NCT02941978). Consecutive inpatients with non-valvular AF who underwent echocardiography were included. sVHD was defined as the presence of at least moderate aortic stenosis (AS) or aortic/mitral/tricuspid regurgitation (AR/MR/TR). Cox regression analyses with covariate adjustments were used for outcome prediction. RESULTS: In total, 983 patients with non-valvular AF (median age 76 [14] years) were analyzed over a median follow-up period of 32 [20] months. sVHD was diagnosed in 575 (58.5%) AF patients. sVHD was associated with all-cause mortality (21.6%/yr vs. 6.5%/yr; adjusted HR [aHR] 1.55, 95% confidence interval [CI] 1.17-2.06; p = 0.02), cardiovascular mortality (16%/yr vs. 4%/yr; aHR 1.70, 95% CI 1.09-2.66; p = 0.02) and heart failure-hospitalization (5.8%/yr vs. 1.8%/yr; aHR 2.53, 95% CI 1.35-4.63; p = 0.02). The prognostic effect of sVHD was particularly evident in patients aged < 80 years and in those without history of heart failure (p for interaction < 0.05, in both subgroups). After multivariable adjustment, moderate/severe AS and TR were associated with mortality, while AS and MR with heart failure-hospitalization. CONCLUSION: Among patients with non-valvular AF, sVHD was highly prevalent and beared high prognostic value across a wide spectrum of clinical outcomes, especially in patients aged < 80 years or in the absence of heart failure. Predominantly AS, as well as MR and TR, were associated with worse prognosis.

Beat-to-Beat P-Wave Analysis Outperforms Conventional P-Wave Indices in Identifying Patients with a History of Paroxysmal Atrial Fibrillation during Sinus Rhythm.

Early identification of patients at risk for paroxysmal atrial fibrillation (PAF) is essential to attain optimal treatment and a favorable prognosis. We compared the performance of a beat-to-beat (B2B) P-wave analysis with that of standard P-wave indices (SPWIs) in identifying patients prone to PAF. To this end, 12-lead ECG and 10 min vectorcardiogram (VCG) recordings were obtained from 33 consecutive, antiarrhythmic therapy naïve patients, with a short history of low burden PAF, and from 56 age- and sex-matched individuals with no AF history. For both groups, SPWIs were calculated, while the VCG recordings were analyzed on a B2B basis, and the P-waves were classified to a primary or secondary morphology. Wavelet transform was used to further analyze P-wave signals of main morphology. Univariate analysis revealed that none of the SPWIs performed acceptably in PAF detection, while five B2B features reached an AUC above 0.7. Moreover, multivariate logistic regression analysis was used to develop two classifiers-one based on B2B analysis derived features and one using only SPWIs. The B2B classifier was found to be superior to SPWIs classifier; B2B AUC: 0.849 (0.754-0.917) vs. SPWIs AUC: 0.721 (0.613-0.813), p value: 0.041. Therefore, in the studied population, the proposed B2B P-wave analysis outperforms SPWIs in detecting patients with PAF while in sinus rhythm. This can be used in further clinical trials regarding the prognosis of such patients.

Circulating microRNAs Related to Bone Metabolism in HIV-Associated Bone Loss.

The pathophysiology of human immunodeficiency virus (HIV)-associated bone loss is complex and to date largely unknown. In this study, we investigated serum expression of microRNAS (miRNAs) linked to bone metabolism in HIV-associated bone loss. This was a case-control study. Thirty male individuals with HIV infection (HIV+) and osteoporosis/osteopenia (HIV+/OP+) (cases) and 30 age-matched male HIV+ individuals with normal bone mass (HIV+/OP-) (controls) were included in the analysis. Thirty male individuals matched for age without HIV infection (HIV-), were also included as second controls. The selected panel of miRNAs was as follows: hsa-miRNA-21-5p; hsa-miRNA-23a-3p; hsa-miRNA-24-2-5p; hsa-miRNA-26a-5p; hsa-miRNA-29a-3p; hsa-miRNA-124-3p; hsa-miRNA-33a-5p; and hsa-miRNA-133a-3p. Within the cohort of HIV+ individuals, relative serum expression of miRNA-21-5p and miRNA-23a-3p was significantly lower (p < 0.001) while the expression of miRNA-24-2-5p was significantly higher (p = 0.030) in HIV+/OP+ compared to HIV+/OP-. Expression of miRNA-21-5p demonstrated a sensitivity of 84.6% and a specificity of 66.7 in distinguishing HIV+/OP+ individuals. Expression of circulating miRNAs related to bone metabolism; miRNA-23a-3p, miRNA-24-2-5p, and miRNA-21-5p is significantly altered in HIV+OP+ individuals, in line with data on other causes of osteoporosis, suggesting a common pattern of circulating miRNAs independent of the underlying cause.

Machine Learning Algorithms and Statistical Approaches for Alzheimer's Disease Analysis Based on Resting-State EEG Recordings: A Systematic Review.

Alzheimer's Disease (AD) is a neurodegenerative disorder and the most common type of dementia with a great prevalence in western countries. The diagnosis of AD and its progression is performed through a variety of clinical procedures including neuropsychological and physical examination, Electroencephalographic (EEG) recording, brain imaging and blood analysis. During the last decades, analysis of the electrophysiological dynamics in AD patients has gained great research interest, as an alternative and cost-effective approach. This paper summarizes recent publications focusing on (a) AD detection and (b) the correlation of quantitative EEG features with AD progression, as it is estimated by Mini Mental State Examination (MMSE) score. A total of 49 experimental studies published from 2009 until 2020, which apply machine learning algorithms on resting state EEG recordings from AD patients, are reviewed. Results of each experimental study are presented and compared. The majority of the studies focus on AD detection incorporating Support Vector Machines, while deep learning techniques have not yet been applied on large EEG datasets. Promising conclusions for future studies are presented.

Expression of Circulating MicroRNAs Linked to Bone Metabolism in Chronic Kidney Disease-Mineral and Bone Disorder.

The pathophysiology of chronic kidney disease-mineral and bone disorder (CKD-MBD) is complex and multifactorial. Recent studies have identified a link between microRNAs (miRNAs) and bone loss. In this study, we investigated the expression of miRNAs in CKD-MBD. In this case-control study, we included thirty patients with CKD-MBD (cases) and 30 age- and gender-matched healthy individuals (controls). Bone mineral density (BMD) and trabecular bone score (TBS) evaluation was performed with dual X-ray absorptiometry. The selected panel of miRNAs included: hsa-miRNA-21-5p; hsa-miRNA-23a-3p; hsa-miRNA-24-2-5p; hsa-miRNA-26a-5p; hsa-miRNA-29a-3; hsa-miRNA-124-3p; hsa-miRNA-2861. The majority of cases had low BMD values. The relative expression of miRNA-21-5p was 15 times lower [fold regulation (FR): -14.7 ± 8.1, p = 0.034), miRNA-124-3p, 6 times lower (FR: -5.9 ± 4, p = 0.005), and miRNA-23a-3p, 4 times lower (FR: -3.8 ± 2.0, p = 0.036) in cases compared to controls. MiRNA-23a-3p was significantly and inversely correlated with TBS, adjusted for calcium metabolism and BMD values (beta = -0.221, p = 0.003, 95% CI -0.360, -0,081) in cases. In a receiver operating characteristic (ROC) analysis, expression of miRNA-124-3p demonstrated 78% sensitivity and 83% specificity in identifying CKD patents with osteoporosis. Serum expression of miRNAs related to osteoblasts (miRNA-23a-3p) and osteoclasts (miRNA-21-5p, miRNA-124-3p) is significantly altered in patients with CKD-MBD.

The Administrative Prevalence of Multiple Sclerosis in Greece on the Basis of a Nationwide Prescription Database.

Objective: To estimate current prevalence of multiple sclerosis (MS) in Greece using administrative data from the nationwide medicine prescription database. Methods: Prescription records of a 24-month period (June 2017-May 2019) were analyzed in order to identify cases of MS. Sex, age, and place of residence were recorded for each identified case. Prevalence of MS was calculated based on the updated records of the Greek population according to Hellenic Statistical Authority. Results: The 2-year cumulative period prevalence of MS was estimated to 197.8 per 100,000 (95% CI 197.6-198.0). In total, 21,218 patients (65.8% female) were identified. During this period, the prevalence of MS was 138.7 per 100,000 (95% CI 138.4-139.0) in men and 253.6 per 100,000 (95% CI 253.3-254.1) in women. Prevalence was higher in the 45-49 age group in both sexes. Analysis of the place of residence revealed higher prevalence in the Attica region and Western Greece while lower prevalence was observed in Northern Greece. No north-south latitude gradient was detected. Point prevalence on 1 January 2019 was calculated to 188.9 per 100,000 (95% CI 188.7-189.1). Regarding treatment, 73.1% of the identified cases received at least once a Disease Modifying Drug. Conclusions: According to this national-level study conducted in Greece, estimated prevalence of MS was found to be similar to those of other European countries. Heterogeneity of MS prevalence across the country was observed and needs further investigation.