Is paclitaxel less cardiotoxic in the treatment of breast cancer before or after doxorubicin? / Qual estratégia terapêutica é menos cardiotóxica no tratamento do câncer de mama: uso de paclitaxel antes ou depois da doxorrubicina?

Background: The combination of doxorubicin (DOX) with paclitaxel (PTX) effectively treats breast cancer (BC). However, DOX-associated cardiotoxicity (CTX) is aggravated by the use of PTX. Consensus is lacking about which drug sequence involves the most CTX. Objectives: To evaluate whether DOX followed by PXT or the reverse sequence has the greatest cardiotoxic potential in the treatment of BC. Methods: Prospective study of women with primary BC who received four cycles of DOX and 12 infusions of PTX. Participants were divided into Group 1 (G1; PXT before DOX) and Group 2 (G2; DOX before PXT) at the discretion of the oncologist. CTX was defined as an absolute reduction in left ventricular ejection fraction (LVEF) > 10% to a value <53%. Patients underwentclinical evaluations and echocardiography before treatment (Phase 1) and one year after treatment (Phase 2). Results: Sixty-nine women were evaluated: 19 in G1 and 50 in G2. The groups had similar clinical characteristics. The doses of radiation, DOX, and PTX used were similar. Eight (11.6%) patients developed CTX: two (10.5%) in G1 and six (12.0%) in G2 (p=0.62). The mean LVEF was similar between groups in Phase 1 (G1=65.1±3.5%; G2=65.2±3.9%; p=0.96), with a significant reduction noted after one year in both groups: G1=61.4±8.1% (p=0.021) and G2=60.8±7.6% (p<0,001). Although lower, mean LVEF remained similar between groups after Phase 2 (p=0.79). Conclusions: In women with BC who underwent chemotherapy, the incidence of CTX at the end of the first year of treatment was similar regardless of whether DOX was used before or after PTX. (AU)

COVID-19 epidemic curve in Brazil: a sum of multiple epidemics, whose inequality and population density in the states are correlated with growth rate and daily acceleration. An ecological study

ABSTRACT Background: The epidemic curve has been obtained based on the 7-day moving average of the events. Although it facilitates the visualization of discrete variables, it does not allow the calculation of the absolute variation rate. Recently, we demonstrated that the polynomial interpolation method can be used to accurately calculate the daily acceleration of cases and deaths due to COVID-19. This study aimed to measure the diversity of epidemic curves and understand the importance of socioeconomic variables in the acceleration, peak cases, and deaths due to COVID-19 in Brazilian states. Methods: Epidemiological data for COVID-19 from federative units in Brazil were obtained from the Ministry of Health's website from February 25 to July 11, 2020. Socioeconomic data were obtained from the Instituto Brasileiro de Geografia e Estatística (https://www.ibge.gov.br/). Using the polynomial interpolation methods, daily cases, deaths and acceleration were calculated. Moreover, the correlation coefficient between the epidemic curve data and socioeconomic data was determined. Results: The combination of daily data and case acceleration determined that Brazilian states were in different stages of the epidemic. Maximum case acceleration, peak of cases, maximum death acceleration, and peak of deaths were associated with the Gini index of the gross domestic product of Brazilian states and population density but did not correlate with the per capita gross domestic product of Brazilian states. Conclusions: Brazilian states showed heterogeneous data curves. Population density and socioeconomic inequality were correlated with a more rapid exponential growth in new cases and deaths.

Covid-19 growth rate analysis: application of a low-complexity tool for understanding and comparing epidemic curves

Abstract INTRODUCTION: The acceleration of new cases is important for the characterization and comparison of epidemic curves. The objective of this study was to quantify the acceleration of daily confirmed cases and death curves using the polynomial interpolation method. METHODS: Covid-19 epidemic curves from Brazil, Germany, the United States, and Russia were obtained. We calculated the instantaneous acceleration of the curve using the first derivative of the representative polynomial. RESULTS: The acceleration for all curves was obtained. CONCLUSIONS: Incorporating acceleration into an analysis of the Covid-19 time series may enable a better understanding of the epidemiological situation.

Subclinical Ventricular Dysfunction Detected by Speckle Tracking Two Years after Use of Anthracycline / Disfunção Ventricular Subclínica Detectada por Speckle Tracking Dois Anos após Uso de Antraciclina

Background: Heart failure is a severe complication associated with doxorubicin (DOX) use. Strain, assessed by two-dimensional speckle tracking (2D-STE), has been shown to be useful in identifying subclinical ventricular dysfunction. Objectives: a) To investigate the role of strain in the identification of subclinical ventricular dysfunction in patients who used DOX; b) to investigate determinants of strain response in these patients. Methods: Cross-sectional study with 81 participants: 40 patients who used DOX ±2 years before the study and 41 controls. All participants had left ventricular ejection fraction (LVEF) ≥55%. Total dose of DOX was 396mg (242mg/ms2). The systolic function of the LV was evaluated by LVEF (Simpson), as well as by longitudinal (εLL), circumferential (εCC), and radial (εRR) strains. Multivariate linear regression (MLR) analysis was performed using εLL (model 1) and εCC (model 2) as dependent variables. Results: Systolic and diastolic blood pressure values were higher in the control group (p < 0.05). εLL was lower in the DOX group (-12.4 ±2.6%) versus controls (-13.4 ± 1.7%; p = 0.044). The same occurred with εCC: -12.1 ± 2.7% (DOX) versus -16.7 ± 3.6% (controls; p < 0.001). The S’ wave was shorter in the DOX group (p = 0.035). On MLR, DOX was an independent predictor of reduced εCC (B = -4.429, p < 0.001). DOX (B = -1.289, p = 0.012) and age (B = -0.057, p = 0.029) were independent markers of reduced εLL. Conclusion: a) εLL, εCC and the S’ wave are reduced in patients who used DOX ±2 years prior to the study despite normal LVEF, suggesting the presence of subclinical ventricular dysfunction; b) DOX was an independent predictor of reduced εCC; c) prior use of DOX and age were independent markers of reduced εLL. .

Fundamento: A insuficiência cardíaca é uma complicação grave associada ao uso da doxorrubicina (DOX). O strain, avaliado por speckle tracking bidimensional (2D-STE), tem se mostrado útil na identificação de disfunção ventricular subclínica. Objetivos: a) Investigar o comportamento do strain na identificação de disfunção ventricular subclínica em pacientes que usaram DOX; b) investigar determinantes do comportamento do strain nestes pacientes. Métodos: Estudo transversal com 81 participantes: 40 pacientes que usaram DOX ± 2 anos antes do estudo e 41 controles. Todos tinham fração de ejeção do ventrículo esquerdo (FEVE) ≥ 55%. A dose total de DOX foi de 396 mg (242 mg/m2). A função sistólica do VE foi avaliada pela FEVE (Simpson), assim como pelo strain longitudinal (εLL), circunferencial (εCC) e radial (εRR). Realizamos análise de regressão linear multivariada (RLM) usando como variáveis dependentes o εLL (modelo 1) e o εCC (modelo 2). Resultados: Os valores da pressão arterial sistólica e diastólica foram maiores no grupo controle (p < 0,05). O εLL foi menor no grupo DOX (-12,4 ± 2,6%) versus controle (-13,4 ± 1,7%; p = 0,044). O mesmo ocorreu em relação ao εCC: -12,1 ± 2,7% (DOX) versus -16,7 ± 3,6% (controles; p < 0,001). A onda S' foi menor no grupo DOX (p = 0,035). Na RLM, a DOX foi preditora independente de redução do εCC (B = -4,429, p < 0,001). DOX (B = -1,289, p = 0,012) e idade (B = -0,057, p = 0,029) foram marcadores independentes de redução do εLL. Conclusões: a) O εLL, o εCC e a onda S' estão reduzidos nos pacientes que usaram DOX ±2 anos antes do estudo, apesar da FEVE ser normal, sugerindo presença de disfunção ventricular subclínica; b) a DOX foi preditora independente de redução do εCC; c) o uso prévio da DOX e a idade foram marcadores independentes de redução do εLL. .