25 research outputs found

    Contributions on joint modeling of sequential times to event with longitudinal information

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    In longitudinal studies it is often of interest to measure the association between a longitudinal marker repeatedly measured in time and the risk for an event. By postulating a model for the joint distribution, we acknowledge this link and we can assess the association between the longitudinal and the survival processes. In this work, we present the joint modeling approach and focus on the extension of the established methodology to include sequential survival times and more than one longitudinal variable. Thus, on the one hand, the purpose of the present work is to introduce the methodology for the joint models (comparing the frequentist and Bayesian approaches) and to develop a new theory to include more than one survival time and more than one longitudinal variable. On the other hand, we study in depth the structure of the R packages that fit joint models (JM and JMbayes) for one survival time and for one longitudinal variable in order to give some hints on how they should be modified to implement the problem we have theoretically formulated

    ThresholdROC: optimum threshold estimation tools for continuous diagnostic tests in R

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    We introduce an R package that estimates decision thresholds in diagnostic settings with a continuous marker and two or three underlying states. The package implements parametric and non-parametric estimation methods based on minimizing an overall cost function, as well as confidence interval estimation approaches to account for the sampling variability of the cut-off. Further features of the package include sample size determination and estimation of diagnostic accuracy measures. We used randomly generated data and two real datasets to illustrate the capabilities and characteristics of the package

    ThresholdROC: Optimum Threshold Estimation Tools for Continuous Diagnostic Tests in R

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    We introduce an R package that estimates decision thresholds in diagnostic settings with a continuous marker and two or three underlying states. The package implements parametric and non-parametric estimation methods based on minimizing an overall cost function, as well as confidence interval estimation approaches to account for the sampling variability of the cut-off. Further features of the package include sample size determination and estimation of diagnostic accuracy measures. We used randomly generated data and two real datasets to illustrate the capabilities and characteristics of the package

    Impact of surgical technique and analgesia on clinical outcomes after lung transplantation A STROBE-compliant cohort study

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    There is paucity of data on the impact of surgical incision and analgesia on relevant outcomes. A retrospective STROBE-compliant cohort study was performed between July 2007 and August 2017 of patients undergoing lung transplantation. Gender, age, indication for lung transplantation, and the 3 types of surgical access (Thoracotomy (T), Sternotomy (S), and Clamshell (C)) were used, as well as 2 analgesic techniques: epidural and intravenous opioids. Outcome variables were: pain scores; postoperative hemorrhage in the first 24 hours, duration of mechanical ventilation, and length of stay at intensive care unit (ICU). Three hundred forty-one patients were identified. Thoracotomy was associated with higher pain scores than Sternotomy (OR 1.66, 95% CI: 1.01; 2.74, P: .045) and no differences were found between Clamshell and Sternotomy incision. The median blood loss was 800 mL [interquartile range (IQR): 500; 1238], thoracotomy patients had 500 mL [325; 818] (P < .001). Median durations of mechanical ventilation in Thoracotomy, Sternotomy, and Clamshell groups were 19 [11; 37] hours, 34 [IQR 16; 57.5] hours, and 27 [IQR 15; 50.5] hours respectively. Thoracotomy group were discharged earlier from ICU (P < .001). Thoracotomy access produces less postoperative hemorrhage, duration of mechanical ventilation, and lower length of stay in ICU, but higher pain scores and need for epidural analgesia

    VET efficacy : evaluation of factors in the workplace training

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    Training in the workplace is a key part of VET studies because allows students to develop their skills in a work setting, and gives important information about how well VET studies prepare skilled workers. However, there is little information about factors that influence the efficacy of training in the workplace. Our aim is to evaluate the efficacy of training in the workplace, through the factors that influence training efficacy. We applied a questionnaire of 57 items (5-point Likert scale), a sample of 1,026 VET students in the area of Barcelona, Spain. The results show that the factor "integration into the workplace" is rated more positively by the VET students (4.19), and the factors "social attitudes" and "individual attitudes" get a low score (3.30 and 2.93, respectively). The study allows the introduction of improvements and changes in these practices in order to improve the quality of VE

    A propensity-score-matched analysis of laparoscopic vs open surgery for rectal cancer in a population-based study

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    Aim: the oncological risk/benefit trade-off for laparoscopy in rectal cancer is controversial. Our aim was to compare laparoscopic vs open surgery for resection of rectal cancer, using unselected data from the public healthcare system of Catalonia. Methods: this was a multicentre retrospective cohort study of all patients who had surgery with curative intent for primary rectal cancer at Catalonian public hospitals from 2011 to 2012. We obtained follow-up data for up to 5 years. To minimize the differences between the two groups, we performed propensity score matching on baseline patient characteristics. We used multivariate Cox proportional hazards regression analyses to assess locoregional relapse at 2 years and death at 2 and 5 years. Results: of 1513 patients with Stage I-III rectal cancer, 933 (61.7%) had laparoscopy (conversion rate 13.2%). After applying our propensity score matching strategy (2:1), 842 laparoscopy patients were matched to 517 open surgery patients. Multivariate Cox analysis of death at 2 years [hazard ratio (HR) 0.65, 95% CI 0.48, 0.87; P = 0.004] and 5 years (HR 0.61, 95% CI 0.5, 0.75; P < 0.001) and of local relapse at 2 years (HR 0.44, 95% CI 0.27, 0.72; P = 0.001) showed laparoscopy to be an independent protective factor compared with open surgery. Cconclusions: laparoscopy results in lower locoregional relapse and long-term mortality in rectal cancer in unselected patients with all-risk groups included. Studies using long-term follow-up of cohorts and unselected data can provide information on clinically relevant outcomes to supplement randomized controlled trials

    Endoscopic biliary drainage in unresectable biliary obstruction: the role of endoscopic ultrasound-guidance in a cohort study

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    Background and study aims: the use of endoscopic ultrasound-guided biliary drainage (EUS-BD) has increased in cases of failed endoscopic retrograde cholangiopancreatography (ERCP) and there are some concerns. The main aim of the study was to determine the role of EUS-BD in a palliative case cohort. The secondary aim was to compare the efficacy, safety and survival of EUS-BD and ERCP procedures. Patients and methods: this was an observational study at a single tertiary institution, with a consecutive inclusion from January 2015 to December 2016. The inclusion criteria were unresectable tumors of the biliopancreatic region with an indication of BD. Statistical comparison analysis was performed between the ERCP and EUS-BD groups. The incidence between groups was compared using the Chi-square and Fisher exact tests. The log rank test was used to compare the risk of death. Results: fifty-two cases with an indication of palliative BD were included in the study. Transpapillary drainage via ERCP was possible in 44 procedures and EUS-BD was required in eight cases; 15.4% of the cohort and seven using lumen apposing metal stent (LAMS). The technical and clinical success of global endoscopic BD was 100% and 88.5% (ERCP: 84.6% and 78.9%; EUS-BD: 100% and 62.5%, respectively). Pancreatitis was the most frequent adverse event (AE) in the ERCP group (9.62%) and bleeding in the EUS-BD (25%). There were fatal AEs in ERCP (1.9%) and EUS-BD (25%) cases. Patient survival was higher with ERCP transpapillary stents compared to EUS-guided stents, which was statistically significant (p = 0.007). Conclusions: the requirement of EUS-BD in palliative biliopancreatic pathology is not marginal. EUS-BD is associated with a lower survival rate and a higher rate of fatal AE, which argues against its use as a first choice procedure

    Host- and Pathogen-Related Factors for Acute Cardiac Events in Pneumococcal Pneumonia

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    Background: Acute cardiac events (ACEs) are increasingly being recognized as a major complication in pneumococcal community-acquired pneumonia (CAP). Information regarding host- and pathogen-related factors for ACEs, including pneumococcal serotypes and clonal complexes, is scarce. Methods: A retrospective study was conducted of a prospective cohort of patients hospitalized for CAP between 1996 and 2019. Logistic regression and funnel plot analyses were performed to determine host- and pathogen-related factors for ACEs. Results: Of 1739 episodes of pneumococcal CAP, 1 or more ACEs occurred in 304 (17.5%) patients, the most frequent being arrhythmia (n = 207), heart failure (n = 135), and myocardial infarction (n = 23). The majority of ACEs (73.4%) occurred within 48 hours of admission. Factors independently associated with ACEs were older age, preexisting heart conditions, pneumococcal bacteremia, septic shock at admission, and high-risk pneumonia. Among 983 pneumococcal isolates, 872 (88.7%) were serotyped and 742 (75.5%) genotyped. The funnel plot analyses did not find any statistically significant association between serotypes or clonal complexes with ACEs. Nevertheless, there was a trend toward an association between CC230 and these complications. ACEs were independently associated with 30-day mortality (adjusted odds ratio, 1.88; 95% CI, 1.11-3.13). Conclusions: ACEs are frequent in pneumococcal pneumonia and are associated with increased mortality. The risk factors defined in this study may help identify patients who must undergo close follow-up, including heart rhythm monitoring, and special care to avoid fluid overload, particularly during the first 48 hours of admission. These high-risk patients should be the target for preventive intervention strategies

    Characteristics and outcomes by ceiling of care of subjects hospitalized with COVID-19 during four waves of the pandemic in a metropolitan area: a multicenter cohort study

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    Introduction The profiles of patients with COVID-19 have been widely studied, but little is known about differences in baseline characteristics and in outcomes between subjects with a ceiling of care assigned at hospital admission and subjects without a ceiling of care. The aim of this study is to compare, by ceiling of care, clinical features and outcomes of hospitalized subjects during four waves of COVID-19 in a metropolitan area in Catalonia. Methods Observational study conducted during the first (March–April 2020), second (October–November 2020), third (January–February 2021), and fourth wave (July–August 2021) of COVID-19 in five centers of Catalonia. All subjects were adults (>¿18 years old) hospitalized with a proven SARS-CoV-2 infection and with therapeutic ceiling of care assessed by the attending physician at hospital admission. Results A total of 5813 subjects were analyzed. Subjects with a ceiling of care were mainly older (difference in median age of 20 years), with more comorbidities (Charlson index 3 points higher) and with fewer clinical signs at baseline than patients without a ceiling of care. Some features of their clinical profiles changed among waves. There were differences in treatments received during hospital admission across waves, but not between subjects with and without a ceiling of care. Subjects with a ceiling of care had a death incidence more than four times the death incidence of subjects a without a ceiling of care (risk ratio (RR) ranging from 3.5 in the first wave to almost 6 in the third and fourth). Incidence of severe pneumonia and complications for subjects with a ceiling of care was around 1.5 times the incidence in subjects without a ceiling of care. Discussion Analysis of hospitalized subjects with SARS-CoV-2 infection should be stratified according to therapeutic ceiling of care to avoid bias and outcome misestimation.This study was partially funded by Secretaria d’Universitats i Recerca del Departament d’Empresa i Coneixement de la Generalitat de Catalunya (2020PANDE00148).Peer ReviewedPostprint (published version

    Persistent COVID-19 symptoms 1 year after hospital discharge: A prospective multicenter study

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    Objective To determine the health status and exercise capacity of COVID-19 survivors one year after hospital discharge. Methods This multicenter prospective study included COVID-19 survivors 12 months after hospital discharge. Participants were randomly selected from a large cohort of COVID-19 patients who had been hospitalized until 15th April 2020. They were interviewed about persistent symptoms, underwent a physical examination, chest X-ray, and a 6-minute walk test (6MWT). A multivariate analysis was performed to determine the risk factors for persistent dyspnea. Results Of the 150 patients included, 58% were male and the median age was 63 (IQR 54-72) years. About 82% reported >= 1 symptoms and 45% had not recovered their physical health. The multivariate regression analysis revealed that the female sex, chronic obstructive pulmonary disease, and smoking were independent risk factors for persistent dyspnea. Approximately 50% completed less than 80% of the theoretical distance on the 6MWT. Only 14% had an abnormal X-ray, showing mainly interstitial infiltrates. A third of them had been followed up in outpatient clinics and 6% had undergone physical rehabilitation. Conclusion Despite the high rate of survivors of the first wave of the COVID-19 pandemic with persistent symptomatology at 12 months, the follow-up and rehabilitation of these patients has been really poor. Studies focusing on the role of smoking in the persistence of COVID-19 symptoms are lacking
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