Pointwise forecast, confidence and prediction intervals in electricity demand and price

Programa Oficial de Doutoramento en Estatística e Investigación Operativa. 555V01[Abstract] Analysis of the electricity demand and price is presented, within the Spanish Electricity Market, applying statistical tools from the field of functional data. It begins with a descriptive analysis of the electrical data, studying its particular features. This kind of data conform a functional time series. Functional outlier detection methods are proposed to deal specifically with functional time series, taking dependence in this data structure into account. Then, a comparative study among different prediction techniques for next-day electricity demand and price is performed. It includes naïve procedures, time series ARIMA models and robust functional principal components analysis. The use of functional regression methods is proposed in this field. Specifically, the functional nonparametric regression model is used together with the semi-functional partial linear regression model, which allows incorporating external covariates as temperature and wind power production. Bootstrap procedures are proposed to build confidence intervals for the considered functional regression models. Validity of these bootstrap procedures is proved theoretically and they are applied to both a simulation study and the electricity demand and price data. Finally, bootstrap procedures are proposed to build prediction intervals and prediction density, which are also applied to the electrical data.[Resumen] Se presenta un análisis de la demanda y el precio de la electricidad, dentro del Mercado Eléctrico Español, aplicando técnicas estadísticas del ámbito de los datos funcionales. En primer lugar, se realiza un análisis descriptivo de los datos eléctricos, en el que se estudian sus principales características. Este tipo de datos conforman una serie de tiempo funcional. Se proponen métodos de detección de atípicos diseñados específicamente para series de tiempo funcionales, teniendo en cuenta la dependencia presente en esta estructura de datos. A continuación, se realiza un estudio comparativo de diferentes técnicas para la predicción de la demanda y precio de la electricidad al día siguiente. Este estudio incluye métodos naïve, modelos ARIMA de series de tiempo y métodos basados en componentes principales funcionales robustas. Se propone el uso de métodos de regresión funcional en este ámbito. En concreto, se utiliza el modelo de regresión funcional no paramétrico y el modelo semi-funcional parcialmente lineal, en el que se incorporan covariables externas como la temperatura y la producción de energía eólica. Considerando los métodos de regresión funcional indicados, se proponen procedimientos bootstrap para el cálculo de intervalos de confianza, cuya validez se prueba teóricamente y se aplican en un estudio de simulación y en los datos eléctricos de demanda y precio. Finalmente, se proponen procedimientos bootstrap para construir intervalos y densidades de predicción, los cuales se aplican al mismo conjunto de datos eléctricos.[Resumo] Preséntase unha análise da demanda e prezo da electricidade, dentro do Mercado Eléctrico Español, aplicando técnicas do ámbito dos datos funcionais. En primeiro lugar, realízase unha análise descritiva dos datos eléctricos, estudando as súas principais características. Este tipo de datos conforman unha serie de tempo funcional. Propóñense métodos de detección de atípicos dese ñados especificamente para series de tempo funcionais, tendo en conta a dependencia presente nesa estrutura de datos. A continuación, lévase a cabo un estudo comparativo de diferentes técnicas para predición da demanda e prezo da electricidade no día seguinte. Este estudo inclúe métodos naïve, modelos ARIMA de series de tempo e métodos baseados en compoñentes principais funcionais robustas. Proponse o uso de métodos de regresión funcional neste ámbito. En concreto, utilízase o modelo de regresión funcional non paramétrico e o modelo semi-funcional parcialmente lineal, no que se incorporan covariables externas como a temperatura e a produción de enerxía eólica. Considerando os métodos de regresión funcional indicados, propóñense procedementos bootstrap para o cálculo de intervalos de confi- anza, nos que a súa validez se proba na teoría e que son aplicados tanto nun estudo de simulación como nos datos eléctricos de demanda e prezo. Finalmente, propóñense procedementos bootstrap para construír intervalos e densidades de predición, que se aplican ao mesmo conxunto de datos eléctricos

Usefulness of the 2MACE Score to Predicts Adverse Cardiovascular Events in Patients With Atrial Fibrillation

[Abstract] We investigated the incidence of nonembolic adverse events in 2 cohorts of patients with atrial fibrillation (AF) and validated the 2MACE score ([metabolic syndrome, age ≥75] [doubled]; [myocardial infarction or revascularization, congestive heart failure {HF}, and stroke, transient ischemic attack or thromboembolism]) as predictor of major adverse cardiovascular events (MACEs). We recruited 2,630 patients with AF from 2 different cohorts (Murcia AF and FANTASIIA). The 2MACE score was calculated, and during a median of 7.2 years (Murcia AF cohort) and 1.01 years (FANTASIIA) of follow-up, we recorded all nonembolic adverse events and MACEs (composite of nonfatal myocardial infarction or revascularization and cardiovascular death). Receiver operating characteristic curves comparison, reclassification and discriminatory analyses, and decision curve analyses were performed to compare predictive ability and clinical usefulness of the 2MACE score against CHA2DS2-VASc. During follow-up, there were 65 MACEs in the Murcia cohort and 60 in the FANTASIIA cohort. Events rates were higher in the high-risk category (score ≥3) (1.94%/year vs 0.81%/year in the Murcia cohort; 6.01%/year vs 1.71%/year, in FANTASIIA, both p <0.001). The predictive performance of 2MACE according to the receiver operating characteristic curve was significantly higher than that of CHA2DS2-VASc (0.662 vs 0.618, p = 0.008 in the Murcia cohort; 0.656 vs 0.565, p = 0.003 in FANTASIIA). Decision curve analyses demonstrated improved clinical usefulness of the 2MACE compared with the CHA2DS2-VASc score. In conclusion, in “real-world” patients with AF, the 2MACE score is a good predictor of MACEs. A score ≥3 should be used to categorize patients at “high risk,” in identifying patients at risk of MACE.Instituto de Salud Carlos III; PI13/00513Instituto de Salud Carlos III; P14/00253Fundación Séneca; 19245/PI/14Instituto Murciano de Investigación Biosanitaria; IMIB16/AP/01/0

Association of body mass index with clinical outcomes in patients with atrial fibrillation: a report from the FANTASIIA Registry

[Abstract] Background. Obesity and atrial fibrillation (AF) frequently coexist and independently increase mortality. We sought to assess the association between obesity and adverse events in patients receiving oral anticoagulants for AF. Methods and Results. Consecutive AF outpatients receiving anticoagulant agents (both vitamin K antagonists and direct oral anticoagulants) were recruited into the FANTASIIA (Atrial fibrillation: influence of the level and type of anticoagulation on the incidence of ischemic and hemorrhagic stroke) registry. This observational, multicenter, and prospective registry of AF patients analyzes the quality of anticoagulation, incidence of events, and differences between oral anticoagulant therapies. We analyzed baseline patient characteristics according to body mass index, normal: <25 kg/m2, overweight: 25–30 kg/m2, and obese: ≥30 kg/m2), assessing all‐cause mortality, stroke, major bleeding and major adverse cardiovascular events (a composite of ischemic stroke, myocardial infarction, and total mortality) at 3 years’ follow‐up. In this secondary prespecified substudy, the association of weight on prognosis was evaluated. We recruited 1956 patients (56% men, mean age 73.8±9.4 years): 358 (18.3%) had normal body mass index, 871 (44.5%) were overweight, and 727 (37.2%) were obese. Obese patients were younger (P<0.01) and had more comorbidities. Mean time in the therapeutic range was similar across body mass index categories (P=0.42). After a median follow‐up of 1070 days, 255 patients died (13%), 45 had a stroke (2.3%), 146 a major bleeding episode (7.5%) and 168 a major adverse cardiovascular event (8.6%). Event rates were similar between groups for total mortality (P=0.29), stroke (P=0.90), major bleeding (P=0.31), and major adverse cardiovascular events (P=0.24). On multivariate Cox analysis, body mass index was not independently associated with all‐cause mortality, cardiovascular mortality, stroke, major bleeding, or major adverse cardiovascular events. Conclusions. In this prospective cohort of patients anticoagulated for AF, obesity was highly prevalent and was associated with more comorbidities, but not with poor prognosis

Association of Body Mass Index With Clinical Outcomes in Patients With Atrial Fibrillation: A Report From the FANTASIIA Registry

Background Obesity and atrial fibrillation (AF) frequently coexist and independently increase mortality. We sought to assess the association between obesity and adverse events in patients receiving oral anticoagulants for AF. Methods and Results Consecutive AF outpatients receiving anticoagulant agents (both vitamin K antagonists and direct oral anticoagulants) were recruited into the FANTASIIA (Atrial fibrillation: influence of the level and type of anticoagulation on the incidence of ischemic and hemorrhagic stroke) registry. This observational, multicenter, and prospective registry of AF patients analyzes the quality of anticoagulation, incidence of events, and differences between oral anticoagulant therapies. We analyzed baseline patient characteristics according to body mass index, normal: <25 kg/m2, overweight: 25-30 kg/m2, and obese: ≥30 kg/m2), assessing all‐cause mortality, stroke, major bleeding and major adverse cardiovascular events (a composite of ischemic stroke, myocardial infarction, and total mortality) at 3 years' follow‐up. In this secondary prespecified substudy, the association of weight on prognosis was evaluated. We recruited 1956 patients (56% men, mean age 73.8±9.4 years): 358 (18.3%) had normal body mass index, 871 (44.5%) were overweight, and 727 (37.2%) were obese. Obese patients were younger (P<0.01) and had more comorbidities. Mean time in the therapeutic range was similar across body mass index categories (P=0.42). After a median follow‐up of 1070 days, 255 patients died (13%), 45 had a stroke (2.3%), 146 a major bleeding episode (7.5%) and 168 a major adverse cardiovascular event (8.6%). Event rates were similar between groups for total mortality (P=0.29), stroke (P=0.90), major bleeding (P=0.31), and major adverse cardiovascular events (P=0.24). On multivariate Cox analysis, body mass index was not independently associated with all‐cause mortality, cardiovascular mortality, stroke, major bleeding, or major adverse cardiovascular events. Conclusions In this prospective cohort of patients anticoagulated for AF, obesity was highly prevalent and was associated with more comorbidities, but not with poor prognosis

Inappropriate doses of direct oral anticoagulants in real-world clinical practice: prevalence and associated factors. A subanalysis of the FANTASIIA Registry

Aims To describe the prevalence and associated factors of inappropriate doses of direct oral anticoagulants (DOAC) in a national registry of patients of real clinical practice. Methods and results  Five hundred and thirty outpatients with atrial fibrillation treated with DOAC were included in a prospective, national, multicentre study. The appropriateness of the doses of DOAC was defined according to the recommendations of the European Heart Rhythm Association. Mean age was 73 ± 9 years, with a 46% of women. Two hundred and sixty-seven patients were prescribed dabigatran, 190 rivaroxaban, and 73 apixaban. A total of 172 patients (32%) did not receive the appropriate dose: 93 patients received a lower dose (18%) and 79 patients a higher dose (15%). In the comparisons among the subgroups of inappropriately low, appropriate, and inappropriately high dose, we observed significant trends to older age (69 ± 8 years vs. 73 ± 10 years vs. 77 ± 6 years), more frequent female sex (37% vs. 46% vs. 59%), antiplatelet drugs (5% vs. 8% vs. 25%), rivaroxaban (14% vs. 38% vs. 53%), and apixaban use (5% vs. 15% vs. 19%), higher CHAD2DS2-VASc (3.00 ± 1.38 vs. 3.58 ± 1.67 vs. 4.59 ± 1.44) and HAS-BLED scores (1.83 ± 0.87 vs. 1.92 ± 1.07 vs. 2.47 ± 1.13), lower body mass index (30 ± 6 kg/m2 vs. 29 ± 4 kg/m2 vs. 28 ± 4 kg/m2) and glomerular filtration rate (74 ± 27 mL/min vs. 70 ± 22 mL/min vs. 63 ± 16 mL/min), and lower frequency of dabigatran use (81% vs. 47% vs. 28%) (all comparisons P ≤ 0.01). Conclusion In this real-life study, 32% of patients received an inappropriate dose of DOAC. Several clinical factors can identify patients at risk of this situation.Sin financiación5.047 JCR (2018) Q1, 30/136 Cardiac & Cardiovascular Systems2.612 SJR (2018) Q1, 27/365 Cardiology and Cardiovascular Medicine, 7/108 Physiology (medical)No data IDR 2018UE

Quality of oral anticoagulation with vitamin K antagonists in 'real-world' patients with atrial fibrillation: a report from the prospective multicentre FANTASIIA registry.

The efficacy and safety of oral anticoagulation (OAC) using the vitamin K antagonists (VKA) are closely associated with the quality of anticoagulation, reflected by time in therapeutic range (TTR). The SAMe-TT2R2 is a risk score developed to predict the quality of anticoagulation control among VKA users. To analyse the quality of anticoagulation and its clinical determinants based on different methods in a prospective cohort of atrial fibrillation patients on VKA treatment participating in the multicentre Spanish observational registry FANTASIIA. Estimated TTR was calculated from Rosendaal, direct method, international normalized ratio variability, and NICE criteria. Time in therapeutic range values were compared for those patients with a SAMe-TT2R2 score 0-2 and >2. One thousand four hundred and seventy patients were analysed (56.4% male, mean age 74.1 ± 9.5 years). Mean TTR was 61.5 ± 25.1 with Rosendaal and 64.7 ± 24.2 with direct method. There was a high correlation between both methods (ρ = 0.805). The prevalence of poor anticoagulation control was 55%. Diabetes mellitus [odds ratio (OR) 1.38; P = 0.008], peripheral artery disease (PAD, OR 1.62; P = 0.048), and HAS-BLED (OR 1.13; P = 0.022) were independently associated with TTR 2. One thousand four hundred and seventy patients were analysed (56.4% male, mean age 74.1 ± 9.5 years). Mean TTR was 61.5 ± 25.1 with Rosendaal and 64.7 ± 24.2 with direct method. There was a high correlation between both methods (ρ = 0.805). The prevalence of poor anticoagulation control was 55%. Diabetes mellitus [odds ratio (OR) 1.38; P = 0.008], peripheral artery disease (PAD, OR 1.62; P = 0.048), and HAS-BLED (OR 1.13; P = 0.022) were independently associated with TTR 2 (P = 0.044), with a specificity of > 90% for predicting TTR  90% for predicting TTR  In a multicentre prospective registry, 55% of AF patients had poor anticoagulation control with diabetes mellitus, PAD, and HAS-BLED being independently associated with TTR