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1.
Microsurgery ; 44(4): e31156, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38549404

RESUMO

INTRODUCTION: Significant morbidity and mortality are hallmarks of the functional decline seen in physically frail patients. The modified frailty index 5 (mFI-5) represents a risk predictor score that has been validated as a comorbidity-based scale in surgery. Serum albumin levels of <3.5 g/dL (hypoalbuminemia) have also been implicated with poor postoperative outcomes. However, the association between these two parameters remains to be investigated. We aimed to elucidate the interdependence of preoperative albumin levels and frailty, as evaluated by the mFI-5 score, and its reliability to prognosticate postoperative results in free flap reconstruction (FFR). METHODS: We conducted a multicenter, retrospective cohort study and accessed the ACS National Surgical Quality Improvement Program (ACS-NSQIP) from 2008 to 2021. We identified all adult patients (≥18 years of age) who underwent a FFR. We extracted perioperative data and lab values including albumin. Multivariable linear and logistic regression analyses were performed to identify independent risk predictors. Main outcomes involved mortality, length of hospital stay, reoperation, medical and surgical complications, and discharge destination within the 30-day postoperative period. RESULTS: A total of 34,571 patients were included in the study, with an average age of 53.9 years (standard deviation [SD] 12.2) and an average body mass index (BMI) of 28.8 (SD 6.1). Of these patients, 7484 were male (21.6%), whereas 22,363 (64.7%) had no frailty (mFI = 0). Additionally, 9466 patients had a frailty score of 1 (27.4%), 2505 had a score of 2 (7.2%), 226 had a score of 3 (0.7%), and 11 had a score of 4 or higher (0.0%). Albumin levels were available for 16,250 patients (47.0%), and among them, 1334 (8.2%) had hypoalbuminemia. Regression analyses showed that higher mFI scores were independent predictors of any, surgical, and medical complications, as well as increased rates of reoperations, unplanned readmissions, and prolonged hospital stays. Hypoalbuminemia independently predicted any, surgical, and medical complications, and higher mortality, reoperation, and longer hospital stay. When both frailty and albumin levels (mFI-5 and albumin) were considered together, this combined assessment was found to be a more accurate predictor of all major outcomes (any, medical and surgical complications, mortality, and reoperation). Further, our analysis identified a weak negative correlation between serum albumin levels and mFI scores (Spearman R: -.1; p < .0001). CONCLUSION: In conclusion, this cohort study highlights the association of hypoalbuminemia with adverse postoperative outcomes, including those not directly related to frailty. Simultaneously, higher mFI scores independently predicted outcomes not associated with hypoalbuminemia. Stemming from these findings, we recommend considering both serum albumin levels and frailty in patients receiving FFR. This perioperative algorithm may help provide more individualized planning including multidisciplinary care and pre and posthabilitation.


Assuntos
Fragilidade , Retalhos de Tecido Biológico , Hipoalbuminemia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fragilidade/complicações , Hipoalbuminemia/complicações , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Albumina Sérica
2.
Biom J ; 66(1): e2200212, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36810737

RESUMO

Method comparisons are essential to provide recommendations and guidance for applied researchers, who often have to choose from a plethora of available approaches. While many comparisons exist in the literature, these are often not neutral but favor a novel method. Apart from the choice of design and a proper reporting of the findings, there are different approaches concerning the underlying data for such method comparison studies. Most manuscripts on statistical methodology rely on simulation studies and provide a single real-world data set as an example to motivate and illustrate the methodology investigated. In the context of supervised learning, in contrast, methods are often evaluated using so-called benchmarking data sets, that is, real-world data that serve as gold standard in the community. Simulation studies, on the other hand, are much less common in this context. The aim of this paper is to investigate differences and similarities between these approaches, to discuss their advantages and disadvantages, and ultimately to develop new approaches to the evaluation of methods picking the best of both worlds. To this aim, we borrow ideas from different contexts such as mixed methods research and Clinical Scenario Evaluation.


Assuntos
Benchmarking , Simulação por Computador
3.
Int J Surg ; 110(2): 684-699, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38052017

RESUMO

BACKGROUND: Breast cancer mortality and treatment differ across racial groups. It remains unclear whether such disparities are also reflected in perioperative outcomes of breast cancer patients undergoing mastectomy. STUDY DESIGN: The authors reviewed the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database (2008-2021) to identify female patients who underwent mastectomy for oncological purposes. The outcomes were stratified by five racial groups (white, Black/African American, Asian, American Indian/Alaska Native, and Native Hawaiian/Pacific Islander) and included 30-day mortality, reoperation, readmission, surgical and medical complications, and non-home discharge. RESULTS: The study population included 222 947 patients, 68% ( n =151 522) of whom were white, 11% ( n =23 987) Black/African American, 5% ( n =11 217) Asian, 0.5% ( n =1198) American Indian/Alaska Native, and 0.5% ( n =1018) Native Hawaiian/Pacific Islander. While 136 690 (61%) patients underwent partial mastectomy, 54 490 (24%) and 31 767 (14%) women received simple and radical mastectomy, respectively. Overall, adverse events occurred in 17 222 (7.7%) patients, the largest portion of which were surgical complications ( n =7246; 3.3%). Multivariable analysis revealed that being of Asian race was protective against perioperative complications [odds ratio (OR)=0.71; P <0.001], whereas American Indian/Alaska Native women were most vulnerable to the complication occurrence (OR=1.41; P <0.001). Black/African American patients had a significantly lower risk of medical (OR=0.59; P <0.001) and surgical complications (OR=0.60; P <0.001) after partial and radical mastectomy, respectively, their likelihood of readmission (OR=1.14; P =0.045) following partial mastectomy was significantly increased. CONCLUSION: The authors identified American Indian/Alaska Native women as particularly vulnerable to complications following mastectomy. Asian patients experienced the lowest rate of complications in the perioperative period. The authors' analyses revealed comparable confounder-adjusted outcomes following partial and complete mastectomy between Black and white races. Their findings call for care equalization in the field of breast cancer surgery.


Assuntos
Neoplasias da Mama , Mastectomia , Humanos , Feminino , Estados Unidos , Masculino , Mastectomia/efeitos adversos , Neoplasias da Mama/cirurgia , Estudos Retrospectivos , Grupos Raciais , Resultado do Tratamento
4.
J Plast Reconstr Aesthet Surg ; 89: 40-50, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134626

RESUMO

BACKGROUND: A variety of breast reconstruction (BR) options are available. The significance of timing on outcomes remains debated. This study aims to compare complications in breast cancer patients undergoing implant-based and autologous BR immediately after mastectomy or at a delayed time point. METHODS: We reviewed the ACS-NSQIP database (2008-2021) to identify all female patients who underwent BR for oncological purposes. Outcomes were stratified by technique (implant-based versus autologous) and timing (immediate versus delayed), and included 30-day mortality, reoperation, (unplanned) readmission, and surgical and medical complications. RESULTS: A total of 21,560 patients were included: 11,237 (52%) implant-based (9791/87% immediate, 1446/13% delayed) and 10,323 (48%) autologous (8378/81% immediate, 1945/19% delayed). Complications occurred in 3666 (17%) patients (implant-based: n = 1112/11% immediate, n = 64/4.4% delayed cohorts; Autologous: n = 2073/25% immediate, n = 417/21% delayed cohorts). In propensity score weighting (PSW) analyses, immediate BR was associated with significantly more complications than delayed BR (p < 0.0001). This was the case for both implant-based and autologous BR, with a greater difference between the two time points noted in implant-based. Confounder-adjusted multivariable analyses confirmed these results. CONCLUSION: At the 30-day time point, delayed BR is associated with significantly lower complication rates than immediate BR, in both the implant-based and autologous cohorts. These findings are not a blanket recommendation in favor of immediate and/or delayed BR. Instead, our insights may guide surgeons and patients in decision-making and help refine patients' eligibility in a case-by-case workup.


Assuntos
Neoplasias da Mama , Mamoplastia , Humanos , Feminino , Mastectomia/efeitos adversos , Mastectomia/métodos , Neoplasias da Mama/complicações , Mamoplastia/efeitos adversos , Mamoplastia/métodos , Reoperação/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos
5.
Pacing Clin Electrophysiol ; 46(12): 1553-1564, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37885302

RESUMO

BACKGROUND: Targeting individual sources identified during atrial fibrillation (AF) has been used as an ablation strategy with varying results. OBJECTIVE: Aim of this study was to evaluate the relationship between regions of interest (ROIs) from CARTOFINDER (CF) mapping and atrial cardiomyopathy from late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR). METHODS: Twenty consecutive patients underwent index catheter ablation for persistent AF (PERS AF). Pre-processed LGE CMR images were merged with the results from CF mapping to visualize harboring regions for focal and rotational activities. Atrial cardiomyopathy was classified based on the four Utah stages. RESULTS: Procedural success was achieved in all patients (n = 20, 100%). LGE CMR revealed an intermediate amount of 21.41% ± 6.32% for LA fibrosis. ROIs were identified in all patients (mean no ROIs per patient n = 416.45 ± 204.57). A tendency towards a positive correlation between the total amount of atrial cardiomyopathy and the total number of ROIs per patient (regression coefficient, ß = 10.86, p = .15) was observed. The degree of fibrosis and the presence of ROIs per segment showed no consistent spatial correlation (posterior: ß = 0.36, p-value (p) = .24; anterior: ß = -0.08, p = .54; lateral: ß = 0.31, p = 39; septal: ß = -0.12; p = .66; right PVs: ß = 0.34, p = .27; left PVs: ß = 0.07, p = .79; LAA: ß = -0.91, p = .12). 12 months AF-free survival was 70% (n = 14) after ablation. CONCLUSION: The presence of ROIs from CF mapping was not directly associated with the extent and location of fibrosis. Further studies evaluating the relationship between focal and rotational activity and atrial cardiomyopathy are mandatory.


Assuntos
Fibrilação Atrial , Cardiomiopatias , Ablação por Cateter , Humanos , Ablação por Cateter/métodos , Meios de Contraste , Fibrose , Gadolínio , Átrios do Coração , Imageamento por Ressonância Magnética/métodos
6.
Int J Surg ; 109(9): 2631-2640, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37788019

RESUMO

BACKGROUND: Global healthcare delivery is challenged by the aging population and the increase in obesity and type 2 diabetes. The extent to which such trends affect the cohort of patients the authors surgically operate on remains to be elucidated. Comprising of 8.7 million surgical patients, the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database can be analyzed to investigate the echo of general population dynamics and forecast future trends. MATERIAL AND METHODS: The authors reviewed the ACS-NSQIP database (2008-2020) in its entirety, extracting patient age, BMI, and diabetes prevalence. Based on these data, the authors forecasted future trends up to 2030 using a drift model. RESULTS: During the review period, median age increased by 3 years, and median BMI by 0.9 kg/m2. The proportion of patients with overweight, obesity class I, and class II rates increased. The prevalence of diabetes rose between 2008 (14.9%) and 2020 (15.3%). The authors forecast the median age in 2030 to reach 61.5 years and median BMI to climb to 29.8 kg/m2. Concerningly, in 2030, eight of ten surgical patients are projected to have a BMI above normal. Diabetes prevalence is projected to rise to 15.6% over the next decade. CONCLUSION: General population trends echo in the field of surgery, with the surgical cohort aging at an alarmingly rapid rate and increasingly suffering from obesity and diabetes. These trends show no sign of abating without dedicated efforts and call for urgent measures and fundamental re-structuring for improved future surgical care.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Idoso , Pré-Escolar , Pessoa de Meia-Idade , Análise por Conglomerados , Bases de Dados Factuais , Obesidade , Complicações Pós-Operatórias
7.
Front Immunol ; 14: 1161301, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37197657

RESUMO

Background: Naturally acquired immunity to malaria may involve different immune mechanisms working in concert, however, their respective contributions and potential antigenic targets have not been clearly established. Here, we assessed the roles of opsonic phagocytosis and antibody-mediated merozoite growth inhibition in Plasmodium falciparum (P. falciparum) infection outcomes in Ghanaian children. Methods: The levels of merozoite opsonic phagocytosis, growth inhibition activities and six P. falciparum antigen-specific IgG of plasma samples from children (n=238, aged 0.5 to 13 years) were measured at baseline prior to the malaria seasons in southern Ghana. The children were then actively and passively followed up for febrile malaria and asymptomatic P. falciparum infection detection in a 50-week longitudinal cohort. P. falciparum infection outcome was modelled as a function of the measured immune parameters while accounting for important demographic factors. Results: High plasma activity of opsonic phagocytosis [adjusted odds ratio (aOR)= 0.16; 95%CI= 0.05 - 0.50, p = 0.002], and growth inhibition (aOR=0.15; 95% CI = 0.04-0.47; p = 0.001) were individually associated with protection against febrile malaria. There was no evidence of correlation (b= 0.13; 95% CI= -0.04-0.30; p=0.14) between the two assays. IgG antibodies against MSPDBL1 correlated with opsonic phagocytosis (OP) while IgG against PfRh2a correlated with growth inhibition. Notably, IgG antibodies against RON4 correlated with both assays. Conclusion: Opsonic phagocytosis and growth inhibition are protective immune mechanisms against malaria that may be acting independently to confer overall protection. Vaccines incorporating RON4 may benefit from both immune mechanisms.


Assuntos
Malária Falciparum , Malária , Animais , Humanos , Criança , Gana , Merozoítos , Antígenos de Protozoários , Proteínas de Protozoários , Anticorpos Antiprotozoários , Fagocitose , Imunoglobulina G , Febre , Infecções Assintomáticas
8.
J Cardiovasc Dev Dis ; 10(4)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37103017

RESUMO

Background: Exercise capacity and patient-reported outcomes are increasingly considered crucial following aortic valve (AV) surgery in non-elderly adults. We aimed to prospectively evaluate the effect of native valve preservation compared with prosthetic valve replacement. Methods: From October 2017 to August 2020, 100 consecutive non-elderly patients undergoing surgery for severe AV disease were included. Exercise capacity and patient-reported outcomes were evaluated upon admission, and 3 months and 1 year postoperatively. Results: In total, 72 patients underwent native valve-preserving procedures (AV repair or Ross procedure, NV group), and 28 patients, prosthetic valve replacement (PV group). Native valve preservation was associated with an increased risk of reoperation (weighted hazard ratio: 10.57 (95% CI: 1.24-90.01), p = 0.031). The estimated average treatment effect on six-minute walking distance in NV patients at 1 year was positive, but not significant (35.64 m; 95% CI: -17.03-88.30, adj. p = 0.554). The postoperative physical and mental quality of life was comparable in both groups. Peak oxygen consumption and work rate were better at all assessment time points in NV patients. Marked longitudinal improvements in walking distance (NV, +47 m (adj. p < 0.001); PV, +25 m (adj. p = 0.004)) and physical (NV, +7 points (adj. p = 0.023); PV, +10 points (adj. p = 0.005)) and mental quality of life (NV, +7 points (adj. p < 0.001); PV, +5 points (adj. p = 0.058)) from the preoperative period to the 1-year follow-up were observed. At 1 year, there was a tendency of more NV patients reaching reference values of walking distance. Conclusions: Despite the increased risk of reoperation, physical and mental performance markedly improved after native valve-preserving surgery and was comparable to that after prosthetic aortic valve replacement.

9.
Biometrics ; 79(3): 1737-1748, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35762259

RESUMO

Randomized clinical trials with time-to-event endpoints are frequently stopped after a prespecified number of events has been observed. This practice leads to dependent data and nonrandom censoring, which can in general not be solved by conditioning on the underlying baseline information. In case of staggered study entry, matters are complicated substantially. The present paper demonstrates that the study design at hand entails general independent censoring in the counting process sense, provided that the analysis is based on study time information only. To illustrate that the filtrations must not use abundant information, we simulated data of event-driven trials and evaluated them by means of Cox regression models with covariates for the calendar times. The Breslow curves of the cumulative baseline hazard showed considerable deviations, which implies that the analysis is disturbed by conditioning on the calendar time variables. A second simulation study further revealed that Efron's classical bootstrap, unlike the (martingale-based) wild bootstrap, may lead to biased results in the given setting, as the assumption of random censoring is violated. This is exemplified by an analysis of data on immunotherapy in patients with advanced, previously treated nonsmall cell lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/terapia , Simulação por Computador , Neoplasias Pulmonares/terapia , Modelos de Riscos Proporcionais , Projetos de Pesquisa , Fatores de Tempo , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Stat Methods Med Res ; 32(2): 425-440, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36384320

RESUMO

A range of regularization approaches have been proposed in the data sciences to overcome overfitting, to exploit sparsity or to improve prediction. Using a broad definition of regularization, namely controlling model complexity by adding information in order to solve ill-posed problems or to prevent overfitting, we review a range of approaches within this framework including penalization, early stopping, ensembling and model averaging. Aspects of their practical implementation are discussed including available R-packages and examples are provided. To assess the extent to which these approaches are used in medicine, we conducted a review of three general medical journals. It revealed that regularization approaches are rarely applied in practical clinical applications, with the exception of random effects models. Hence, we suggest a more frequent use of regularization approaches in medical research. In situations where also other approaches work well, the only downside of the regularization approaches is increased complexity in the conduct of the analyses which can pose challenges in terms of computational resources and expertise on the side of the data analyst. In our view, both can and should be overcome by investments in appropriate computing facilities and educational resources.

11.
Biom J ; 2022 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-36529690

RESUMO

In psychology, linear discriminant analysis (LDA) is the method of choice for two-group classification tasks based on questionnaire data. In this study, we present a comparison of LDA with several supervised learning algorithms. In particular, we examine to what extent the predictive performance of LDA relies on the multivariate normality assumption. As nonparametric alternatives, the linear support vector machine (SVM), classification and regression tree (CART), random forest (RF), probabilistic neural network (PNN), and the ensemble k conditional nearest neighbor (EkCNN) algorithms are applied. Predictive performance is determined using measures of overall performance, discrimination, and calibration, and is compared in two reference data sets as well as in a simulation study. The reference data are Likert-type data, and comprise 5 and 10 predictor variables, respectively. Simulations are based on the reference data and are done for a balanced and an unbalanced scenario in each case. In order to compare the algorithms' performance, data are simulated from multivariate distributions with differing degrees of nonnormality. Results differ depending on the specific performance measure. The main finding is that LDA is always outperformed by RF in the bimodal data with respect to overall performance. Discriminative ability of the RF algorithm is often higher compared to LDA, but its model calibration is usually worse. Still LDA mostly ranges second in cases it is outperformed by another algorithm, or the differences are only marginal. In consequence, we still recommend LDA for this type of application.

13.
Adv Stat Anal ; 106(3): 349-382, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432617

RESUMO

A pandemic poses particular challenges to decision-making because of the need to continuously adapt decisions to rapidly changing evidence and available data. For example, which countermeasures are appropriate at a particular stage of the pandemic? How can the severity of the pandemic be measured? What is the effect of vaccination in the population and which groups should be vaccinated first? The process of decision-making starts with data collection and modeling and continues to the dissemination of results and the subsequent decisions taken. The goal of this paper is to give an overview of this process and to provide recommendations for the different steps from a statistical perspective. In particular, we discuss a range of modeling techniques including mathematical, statistical and decision-analytic models along with their applications in the COVID-19 context. With this overview, we aim to foster the understanding of the goals of these modeling approaches and the specific data requirements that are essential for the interpretation of results and for successful interdisciplinary collaborations. A special focus is on the role played by data in these different models, and we incorporate into the discussion the importance of statistical literacy and of effective dissemination and communication of findings.

14.
Alzheimers Dement (N Y) ; 8(1): e12268, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35229024

RESUMO

INTRODUCTION: People with type 2 diabetes have increased risk of dementia. Glucagon-like peptide-1 (GLP-1) receptor agonists (RAs) are among the promising therapies for repurposing as a treatment for Alzheimer's disease; a key unanswered question is whether they reduce dementia incidence in people with type 2 diabetes. METHODS: We assessed exposure to GLP-1 RAs in patients with type 2 diabetes and subsequent diagnosis of dementia in two large data sources with long-term follow-up: pooled data from three randomized double-blind placebo-controlled cardiovascular outcome trials (15,820 patients) and a nationwide Danish registry-based cohort (120,054 patients). RESULTS: Dementia rate was lower both in patients randomized to GLP-1 RAs versus placebo (hazard ratio [HR]: 0.47 (95% confidence interval [CI]: 0.25-0.86) and in the nationwide cohort (HR: 0.89; 95% CI: 0.86-0.93 with yearly increased exposure to GLP-1 RAs). DISCUSSION: Treatment with GLP-1 RAs may provide a new opportunity to reduce the incidence of dementia in patients with type 2 diabetes.

15.
Pathogens ; 10(5)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069514

RESUMO

The replication of viruses in secondary lymphoid organs guarantees sufficient amounts of pattern-recognition receptor ligands and antigens to activate the innate and adaptive immune system. Viruses with broad cell tropism usually replicate in lymphoid organs; however, whether a virus with a narrow tropism relies on replication in the secondary lymphoid organs to activate the immune system remains not well studied. In this study, we used the artificial intravenous route of infection to determine whether Influenza A virus (IAV) replication can occur in secondary lymphatic organs (SLO) and whether such replication correlates with innate immune activation. Indeed, we found that IAV replicates in secondary lymphatic tissue. IAV replication was dependent on the expression of Sialic acid residues in antigen-presenting cells and on the expression of the interferon-inhibitor UBP43 (Usp18). The replication of IAV correlated with innate immune activation, resulting in IAV eradication. The genetic deletion of Usp18 curbed IAV replication and limited innate immune activation. In conclusion, we found that IAV replicates in SLO, a mechanism which allows innate immune activation.

16.
Eur Heart J Digit Health ; 2(3): 424-436, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36713608

RESUMO

Aims: Artificial intelligence (AI) and machine learning (ML) promise vast advances in medicine. The current state of AI/ML applications in cardiovascular medicine is largely unknown. This systematic review aims to close this gap and provides recommendations for future applications. Methods and results: Pubmed and EMBASE were searched for applied publications using AI/ML approaches in cardiovascular medicine without limitations regarding study design or study population. The PRISMA statement was followed in this review. A total of 215 studies were identified and included in the final analysis. The majority (87%) of methods applied belong to the context of supervised learning. Within this group, tree-based methods were most commonly used, followed by network and regression analyses as well as boosting approaches. Concerning the areas of application, the most common disease context was coronary artery disease followed by heart failure and heart rhythm disorders. Often, different input types such as electronic health records and images were combined in one AI/ML application. Only a minority of publications investigated reproducibility and generalizability or provided a clinical trial registration. Conclusions: A major finding is that methodology may overlap even with similar data. Since we observed marked variation in quality, reporting of the evaluation and transparency of data and methods urgently need to be improved.

17.
Contemp Clin Trials ; 99: 106213, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33188930

RESUMO

The usual development cycles are too slow for the development of vaccines, diagnostics and treatments in pandemics such as the ongoing SARS-CoV-2 pandemic. Given the pressure in such a situation, there is a risk that findings of early clinical trials are overinterpreted despite their limitations in terms of size and design. Motivated by a non-randomized open-label study investigating the efficacy of hydroxychloroquine in patients with COVID-19, we describe in a unified fashion various alternative approaches to the analysis of non-randomized studies. A widely used tool to reduce the impact of treatment-selection bias are so-called propensity score (PS) methods. Conditioning on the propensity score allows one to replicate the design of a randomized controlled trial, conditional on observed covariates. Extensions include the g-computation approach, which is less frequently applied, in particular in clinical studies. Moreover, doubly robust estimators provide additional advantages. Here, we investigate the properties of propensity score based methods including three variations of doubly robust estimators in small sample settings, typical for early trials, in a simulation study. R code for the simulations is provided.


Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , COVID-19/epidemiologia , Ensaios Clínicos como Assunto/organização & administração , Hidroxicloroquina/uso terapêutico , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Causalidade , Ensaios Clínicos como Assunto/normas , Humanos , Hidroxicloroquina/administração & dosagem , Hidroxicloroquina/efeitos adversos , Pandemias , Pontuação de Propensão , SARS-CoV-2 , Tamanho da Amostra
18.
Front Immunol ; 11: 1849, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32973762

RESUMO

Immune activation within the tumor microenvironment is one promising approach to induce tumor regression. Certain viruses including oncolytic viruses such as the herpes simplex virus (HSV) and non-oncolytic viruses such as the lymphocytic choriomeningitis virus (LCMV) are potent tools to induce tumor-specific immune activation. However, not all tumor types respond to viro- and/or immunotherapy and mechanisms accounting for such differences remain to be defined. In our current investigation, we used the non-cytopathic LCMV in different human melanoma models and found that melanoma cell lines produced high levels of CCL5 in response to immunotherapy. In vivo, robust CCL5 production in LCMV infected Ma-Mel-86a tumor bearing mice led to recruitment of NK cells and fast tumor regression. Lack of NK cells or CCL5 abolished the anti-tumoral effects of immunotherapy. In conclusion, we identified CCL5 and NK cell-mediated cytotoxicity as new factors influencing melanoma regression during virotherapy.


Assuntos
Infecções por Arenaviridae/imunologia , Quimiocina CCL5/imunologia , Imunoterapia/métodos , Células Matadoras Naturais/imunologia , Melanoma/imunologia , Animais , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Vírus Oncolíticos/imunologia
19.
Contraception ; 102(3): 201-206, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32511945

RESUMO

OBJECTIVE: The primary objectives were to (1) identify risk factors for surgical evacuation following medical termination of second-trimester pregnancies in Denmark and (2) assesses if these risk factors were able to explain the a priori observed variation in risk of surgical evacuation among Danish hospitals and the a priori observed decline in risk throughout time. The secondary objective was to estimate the risk of major surgery following second-trimester medical abortion. STUDY DESIGN: We conducted a nationwide cohort study including all pregnancies terminated with mifepristone/misoprostol in second trimester in women aged 15-49 years through the period 2006-2017 in Denmark. All included pregnancies were followed for eight weeks from induction. Data were retrieved from national health registers. Multiple logistic regression provided adjusted odds ratios (ORs) of surgical evacuation with 95% confidence intervals (CI). Risk of major surgery was assessed and reported descriptively. RESULTS: Of 5702 abortions, 2934 (52%) underwent surgical evacuation. The proportion of surgical evacuations decreased linearly from 72% in 13th gestational week to 17% in week 22 (p < 0.001). Compared to 25-29-year-olds, a reduced risk of surgical evacuation was observed in the youngest age group, 15-19 years (OR 0.77; 95% CI 0.61-0.99), while the risk among women aged 30-49 years did not differ significantly from the reference group. Compared to nulliparas, women with a history of only vaginal deliveries with spontaneous delivery of placenta had a decreased risk of surgical evacuation, OR 0.79 (95% CI 0.68-0.92). The OR of surgical evacuation varied from 0.05 (95% CI 0.02-0.15) to 2.38 (95% CI 1.71-3.31) among the hospitals (Copenhagen University Hospital as the reference) and declined significantly throughout the study period (OR for one-year increase in calendar time 0.82; 95% CI 0.81-0.84). Of the 5702 abortions, ten (0.2%) underwent major surgery following medical induction, including one laparoscopy, three hysterotomies, five laparotomies, and one hysterectomy. CONCLUSION: Risk of surgical evacuation of second-trimester medical abortions decreased with increasing gestational age and was reduced in women aged 15-19 years as well as in women with a history of only vaginal deliveries with spontaneous delivery of the placenta. However, these risk factors could not explain the significant variation in risk of surgical evacuation among hospitals and the decline in risk by time, suggestive of an unwarranted variation in risk of surgical evacuation following second-trimester medical termination of pregnancy in Denmark. Major surgery following medical induction was uncommon. IMPLICATION: Risk of surgical evacuation following medical termination of second-trimester pregnancy declined by calendar time and varied among Danish hospitals. Risk factors for surgical evacuation could not explain the difference by time and site of induction, suggestive of an unwarranted variation in the risk of surgical evacuation following second-trimester medical abortions in Denmark.


Assuntos
Aborto Induzido , Misoprostol , Estudos de Coortes , Dinamarca , Feminino , Humanos , Recém-Nascido , Mifepristona , Gravidez , Segundo Trimestre da Gravidez
20.
J Clin Med ; 9(5)2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32443573

RESUMO

The objective of this study was to provide a comprehensive examination of the relation of complicated and uncomplicated mild traumatic brain injury (mTBI) with multidimensional outcomes at three- and six-months after TBI. We analyzed data from the Collaborative European NeuroTrauma Effectiveness Research (CENTER-TBI) research project. Patients after mTBI (Glasgow Coma scale (GCS) score of 13-15) enrolled in the study were differentiated into two groups based on computed tomography (CT) findings: complicated mTBI (presence of any traumatic intracranial injury on first CT) and uncomplicated mTBI (absence of any traumatic intracranial injury on first CT). Multidimensional outcomes were assessed using seven instruments measuring generic and disease-specific health-related quality of life (HRQoL) (SF-36 and QOLIBRI), functional outcome (GOSE), and psycho-social domains including symptoms of post-traumatic stress disorder (PTSD) (PCL-5), depression (PHQ-9), and anxiety (GAD-7). Data were analyzed using a multivariate repeated measures approach (MANOVA-RM), which inspected mTBI groups at three- and six-months post injury. Patients after complicated mTBI had significantly lower GOSE scores, reported lower physical and mental component summary scores based on the SF-36 version 2, and showed significantly lower HRQoL measured by QOLIBRI compared to those after uncomplicated mTBI. There was no difference between mTBI groups when looking at psychological outcomes, however, a slight improvement in PTSD symptoms and depression was observed for the entire sample from three to six months. Patients after complicated mTBI reported lower generic and disease specific HRQoL and worse functional outcome compared to individuals after uncomplicated mTBI at three and six months. Both groups showed a tendency to improve from three to six months after TBI. The complicated mTBI group included more patients with an impaired long-term outcome than the uncomplicated group. Nevertheless, patients, clinicians, researchers, and decisions-makers in health care should take account of the short and long-term impact on outcome for patients after both uncomplicated and complicated mTBI.

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