Predictive Factors Research Articles

S856 Clinical Predictive Factors for Endoscopic Findings in Acute Gastrointestinal Bleeding

S856 Clinical Predictive Factors for Endoscopic Findings in Acute Gastrointestinal Bleeding

173 - Predictive factors for clean intermittent catheterization after intravesical onabotulinumtoxinA injections in women with overactive bladder syndrome: A Danish retrospective cohort study

173 - Predictive factors for clean intermittent catheterization after intravesical onabotulinumtoxinA injections in women with overactive bladder syndrome: A Danish retrospective cohort study

Comprehensive secondary analysis of thrombotic events in pediatric patients receiving extracorporeal membrane oxygenation: A prospective cohort study.

This study aims to describe laboratory and clinical factors associated with thrombotic events during prolonged pediatric extracorporeal membrane oxygenation. A secondary analysis of a multi-center prospective study performed between 2012 and 2014. Patients under the age of 19years that received extracorporeal membrane oxygenation for at least 4days of therapy were included (n = 385). Univariable analysis and binomial regression were performed to evaluate predictive factors of single and multiple thrombotic events. A posteriori scoring tool was created to categorize thrombotic event severity. Over 39% of children receiving prolonged ECMO experienced a thrombotic event (TE). Binomial regression demonstrated an association between higher transfused platelet volume (mL/kg) (OR 1.04, CI: 95% 1.01-1.06, p = 0.003), Anti-Xa (OR 5.38, CI: 95% 1.22-23.8, p = 0.026) and aPTT (OR 1.01, CI: 95% 1.00-1.02, p = 0.032) the day prior to TE. Patients experiencing multiple TEs were associated with higher platelet transfusion volume (mL/kg) (OR 1.08, CI: 95% 1.05-1.12, p =< 0.001), antithrombin III (OR 1.03, CI: 95% 1.01-1.04, p = 0.001) and aPTT (OR 1.02, CI: 95% 1.01-1.03, p = 0.009). Patients experiencing multiple thrombotic events had a higher risk of 28-day mortality based on a cumulative clot severity score >4 (OR 2.37 (CI: 95% 1.32-4.24). Current lab tests show limited sensitivity to predict these events the day prior in a vulnerable patient group, leading to potential ECMO circuit failures. Patients with multiple thrombotic events during ECMO therapy face increased mortality risks, highlighting the need for dynamic reporting tools like clot severity scores and detailed documentation of interventions to enhance understanding and improve outcomes.

Analysis of the Predictive Factors for Chronic Endometritis Recurrence in Infertile Women.

To identify the predictive factors for the recurrence of chronic endometritis (CE) in infertile women. In this case-control study, 1170 infertile women recovered from CE and underwent fertility treatment between December 2018 and August 2021. Among the 146 women (12.5%) who did not conceive or experienced pregnancy loss in 18 months after CE recovery, 105 consecutive women who underwent repeat endometrial biopsy for CD138 immunostaining and endometrial bacterial culturing were recruited. Thereafter, patients with and without CE recurrence were compared. The total recurrence rate of CE was 29.5% (31 women). Multivariable logistic regression analysis to determine predictive factors for CE recurrence revealed that hysteroscopic surgery (odds ratio [OR], 0.10; 95% confidence interval [CI], 0.02-0.56; p=0.0009) and pregnancy loss (OR, 4.13; 95% CI, 1.31-13.05; p=0.016) were significantly associated with decreased and increased CE recurrence rates, respectively. Also, reexamination with CD138 immunostaining after 16-18 months (OR, 9.75; 95% CI, 1.47-64.64; p=0.024) was significantly associated with increased CE recurrence rates. Among 49 patients without a history of pregnancy loss, the cumulative CE recurrence rates after 6, 12, and 18 months were 5.6%, 13.5%, and 20.4%, respectively. We recommend reexamination with endometrial CD138 immunostaining in patients with pregnancy loss or long-term infertility during fertility treatment. Hysteroscopic surgery without antibiotic therapy for CE associated with intrauterine abnormalities is also recommended.

Cognitive improvements linked to lysophosphatidylethanolamine after olanzapine treatment in drug-naïve first-episode schizophrenia.

Cognitive impairments are a hallmark symptom of schizophrenia (SCZ). Phosphatidylethanolamine (PE) is the second most abundant phospholipid in mammalian cells, yet its role in cognitive deficits remains unexplored. The aim of this study was to investigate the association between plasma LysoPE and cognitive improvements following olanzapine monotherapy in drug-naïve first-episode (DNFE) SCZ patients. Twenty-five female DNFE SCZ patients were treated with olanzapine for four weeks, and cognitive function was assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) at baseline and after the 4-week follow-up. Utilizing an untargeted ultra-performance liquid chromatography-mass spectrometry (UPLC-MS)-based metabolomics approach, we measured LysoPE concentrations. Significant improvements in immediate and delayed memory domains were observed post-treatment. We identified nine differential LysoPE species after olanzapine monotherapy, with increased concentrations for all LysoPE except LysoPE (22:6). Elevated LysoPE (22:1) concentration positively correlated with cognitive improvement in patients. Baseline LysoPE (16:1) emerged as a predictive factor for cognitive improvement following olanzapine monotherapy. This study offers preliminary evidence for the involvement of LysoPE in cognitive improvements observed in drug-naïve first-episode SCZ patients after olanzapine treatment.

Predictive value of hepatic venous pressure gradient in cirrhotic portal vein thrombosis development.

There are lots of risk factors reported for cirrhotic portal vein thrombosis (PVT) development, however, the relationship between hepatic venous pressure gradient (HVPG) and PVT development remains unclear. The clinical outcomes of cirrhotic patients who had no PVT and underwent HVPG measurement at baseline between March 2018 and March 2022 were analyzed retrospectively. Screening for non-tumoral PVT development was implemented by contrast-enhanced computed tomography and/or magnetic resonance imaging every 6-12 months. Eighty-two cirrhotic patients were evaluated over a follow-up period. Of these, 12 patients (14.6%) experienced the development of PVT. The occurrence of non-tumoral PVT at one, two, and three years were 6.6%, 11.7%, and 22.2% respectively. HVPG (p=0.038;HR 1.07;95%CI 1.00-1.14) and alcohol liver disease (ALD) (p=0.019;HR 4.20;95%CI 1.27-13.89) were independently associated with a high PVT risk. The cutoff value of HVPG was 17.52 mmHg. The cumulative incidence of PVT differed significantly among groups stratified by HVPG thresholds of 16mmHg (P=0.011). The sensitivity and specificity of HVPG≥16mmHg in predicting PVT development were 100.0% and 35.7%. In patients with liver cirrhosis, the value of HVPG was the independent predictive factor of PVT development. Screening for PVT was recommended during follow-up in patients with HVPG≥16 mmHg.

Modeling Overall Survival in Patients With Pancreatic Cancer From a Pooled Analysis of Phase II Trials.

We evaluated the validity of surrogacy of progression-free survival (PFS) or time-to-progression (TTP) and overall response rate (ORR) in phase II trials of pancreatic ductal adenocarcinoma (PDAC). In addition, we explored the impact of predictive variables on overall survival (OS) and developed an optimal OS model. We analyzed 1867 clinical endpoint from 619 phase II PDAC trials with a systematic search from PubMed. Endpoint correlations were determined by Spearman's rank correlation. The assessed predictive factors included PFS/TTP, treatment size, therapy type, stage, and previous treatment. The relationship between predictors and OS was explored by a gamma generalized linear model (GLM) with a log-link function and compared with linear models. The Spearman rank correlation coefficient between PFS/TTP and OS was 0.88 (95% confidence interval [CI] 0.85-0.89; p < 0.0001; n = 610) and between ORR and OS was 0.58 (0.52-0.64; p < 0.0001; n = 514). Model comparison favored the GLM model over the linear model, offering more accurate predictions for higher OS values. Consequently, PFS/TTP was the strongest predictor (pseudo-R2 = 0.75), with 1 added median PFS/TTP month associated with 13% (95% CI 13%-14%) increase in median OS. Subgroup analysis revealed that chemotherapy conferred significantly longer OS compared to targeted therapy in 1-Agent and 2-Agent trials, exhibiting a "very large" and "medium" effect size, respectively (rank biserial, rrb = 0.40 [95% CI 0.22-0.56] and rrb = 0.29 [0.16-0.41], both p < 0.0001), although inconsistent efficacy in 3-Agent trials (rrb = 0.12 [-0.07-0.30], p = 0.21). PFS/TTP is a more reliable surrogate than ORR and a strong predictor of OS in phase II trials of pancreatic cancer. Moreover, gamma GLM (log-link function) is a robust tool for modeling positively skewed survival data with non-constant variance, thus can be applied to other cancers' OS data of such nature.

An In-depth Single-center Retrospective Assessment of In-hospital Outcomes in Acute Myocardial Infarction Patients with and without Diabetes.

Objective This study examined variations in in-hospital mortality causes and identified independent mortality predictors among patients with acute myocardial infarction (AMI) with and without diabetes mellitus (DM). Methods We examined factors influencing in-hospital mortality in a single-center retrospective observational study. Separate multivariate analyses were conducted for both groups to identify independent predictors of in-hospital mortality. Patients This study included consecutive patients admitted to Iwate Medical University Hospital between January 2012 and December 2017 with a diagnosis of AMI. Results Of 1,140 patients meeting the AMI criteria (average age: 68.2±12.8 years old, 75% men), 408 (35.8%) had diabetes. The DM group had a 1.87-times higher 30-day mortality rate, a lower prevalence of ST-elevated MI (56.6% vs. 65.3% in non-DM, p=0.004), and more frequent non-cardiac causes of death (32% vs. 14% in non-DM, p=0.046) than the non-DM group. Independent predictors of in-hospital mortality in both groups were cardiogenic shock (CS) [DM: hazard ratio (HR) 6.59, 95% confidence interval (CI) 2.90-14.95; non-DM: HR 4.42, 95% CI 1.99-9.77] and renal dysfunction (DM: HR 5.64, 95% CI 1.59-20.04; non-DM: HR 5.92, 95% CI 1.79-19.53). Among patients with DM, a history of stroke was an additional independent predictor of in-hospital mortality (HR 2.59, 95% CI 1.07-6.31). Conclusion Notable disparities were identified in the causes of death and predictive factors of mortality between these two groups of patients with AMI. To further improve AMI outcomes, individualized management and prioritizing non-cardiac comorbidities during hospitalization may be crucial, particularly in patients with DM.

EP.07G.04 Clinical Implications of Spread Through Air Spread as Prognostic and Predictive Factors for Patients with Stage IA-B Non-Small Cell Lung Cancer

EP.07G.04 Clinical Implications of Spread Through Air Spread as Prognostic and Predictive Factors for Patients with Stage IA-B Non-Small Cell Lung Cancer

Isolated non-immune-mediated second-degree atrioventricular block in the fetus: natural history and predictive factors for spontaneous recovery.

To determine the clinical course of fetal isolated non-immune-mediated second-degree atrioventricular block (AVB) and the factors associated with spontaneous recovery in these cases. Fetuses with isolated non-immune-mediated second-degree AVB were recruited prospectively between 2014 and 2022. These fetuses were divided into two groups: those which recovered spontaneously and those which did not. Maternal and fetal characteristics and intrauterine and postnatal outcomes were compared between the two groups. The study cohort included 20 fetuses with isolated non-immune-mediated second-degree AVB, diagnosed at a median gestational age of 22.0 (range, 17.0-35.0) weeks. In 12 fetuses, 1:1 atrioventricular conduction was restored spontaneously in utero and there was no recurrence during the postnatal follow-up period. In the remaining eight fetuses, second-degree AVB was maintained and, in six of these, the pregnancy was terminated on parental request. Of the two liveborn children who had persistent second-degree AVB prenatally, one had progressed to complete AVB at the latest follow-up, at the age of 34 months, but was asymptomatic, without heart enlargement or dysfunction. The other child progressed to complete AVB after delivery and was diagnosed with type-2 long QT syndrome. This infant died aged 2 months. Fetuses in the group that recovered spontaneously had earlier gestational age at diagnosis (median, 20.0 (range, 17.0-26.0) vs 24.5 (range, 18.0-35.0) weeks; P = 0.004) and higher atrial rate at diagnosis (median, 147 (range, 130-160) vs 138 (range, 125-149) bpm; P = 0.006) in comparison with the group that did not recover spontaneously. The best cut-off values for prediction of failure to recover spontaneously were 22.5 weeks' gestational age at diagnosis and 144 bpm atrial rate at diagnosis, with sensitivities of 87.5% and 75.0%, respectively, and specificities of 92.0% and 87.5%, respectively. The outcome of 60% of fetuses with isolated non-immune-mediated second-degree AVB was favorable. Earlier gestational age and higher atrial rate at diagnosis were associated with spontaneous reversion to normal sinus rhythm. Prenatal genetic testing should be performed in cases with persistent AVB, to exclude heritable disorders including long QT syndrome. These findings provide important information for clinical management and prenatal counseling in these cases. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

General practice trainee, supervisor and educator perspectives on the transitions in postgraduate training: a scoping review

Transitions are a period and a process, through which there is a longitudinal adaptation in response to changing circumstances in clinical practice and responsibilities. While the experience of the transition...

Predictive factors to return to sport after surgical management of ankle fractures.

Achieving Return to Sport (RTS) is crucial in managing ankle fractures for athletes. This study aimed to identify RTS factors post-surgical fixation of ankle fractures. A retrospective analysis was conducted on 93 active patients with surgically treated displaced or unstable ankle fractures from January 2020 to January 2021. The median follow-up was 2.12 years. Clinical, functional, and radiographic aspects were evaluated. Among the athletes, 82.8% resumed sports post-surgery, with 26.9% returning within 3 months and 75.3% at 1 year. At 1 year, 40.9% regained their pre-injury activity level. There was a significant association between RTS and AO/OTA fracture subtype (p = 0.038). Unimalleolar fractures had the best outcomes, with 100% achieving RTS in a median of 4 months. Bimalleolar fractures had 80.77% RTS in 6 months, and trimalleolar fractures had 65.22% RTS in 8 months. AO/OTA subtypes B and C predicted lower RTS to pre-injury levels, with delayed recovery for bimalleolar and trimalleolar fractures. These findings underscore the impact of fracture severity on RTS, with more complex fractures leading to poorer and delayed recovery outcomes. Level of evidence: III.

The effect of genital self-image on sexual satisfaction and stress in women after vaginal delivery.

Pregnancy, childbirth, and postpartum periods bring along biological, psychological, and social changes that could affect women's sexual health. The aim of this study was to evaluate the effect of genital self-image on sexual satisfaction and stress in women who had a vaginal delivery. This descriptive and cross-sectional study was conducted online between June and September 2023 by using snowball sampling and the data collection forms prepared in the GoogleDocs program. Women who had a normal vaginal delivery were included, were within 6 weeks to 1 year postpartum, were able to use at least one of the social media networks (e-mail, WhatsApp, Facebook, and Instagram), and volunteered to participate in the research. Data were collected through the Personal Information Form, the "Female Genital Self-Image Scale," the "Golombok-Rust Inventory of Sexual Satisfaction," and the "Female Sexual Distress Scale-Revised." The average age of the participating women was 30.54±5.83 years (n=235). The participants' mean scores were 18.94±2.92 for the Female Genital Self-Image Scale, 40.07±15.51 for the Golombok-Rust Inventory of Sexual Satisfaction, and 8.85±8.50 for the Female Sexual Distress Scale-Revised total. A statistically significant and negative relationship was found between Female Genital Self-Image Scale and Golombok-Rust Inventory of Sexual Satisfaction and Female Sexual Distress Scale-Revised total scores (r=-0.183, p<0.01; r=-0.387, p<0.01). Regression analysis (forward) was performed, and genital self-image was found to be the predictive factor affecting sexual satisfaction and stress. This study found that women had a medium level of genital self-image and sexual satisfaction and a low level of sexual distress.

Diversity, Geographical Distribution and Predictive Factors of Hepatitis C Virus Genotypes and Subtypes in Rwanda

Existing data on the prevalence of hepatitis C virus (HCV) genotypes and subtypes in Rwanda need to be strengthened. The aim of this study was to identify HCV genotypes and subtypes among HCV-infected patients, as well as their geographical distribution in Rwanda, and to identify the social and economic factors that could influence HCV epidemiology which would make it possible to target national preventive and management actions for infected patients. This study included 560 patients with confirmed chronic HCV infection. Patients were recruited from various health facilities in the four provinces of Rwanda as well as in the City of Kigali and had never received treatment with direct-acting antiviral (DAAs). HCV viral loads were measured using Cobas® AmpliPrep/Cobas® TaqMan® HCV Quantitative Test, version 2.0. HCV genotyping was performed using an in-house sequencing protocol targeting the NS5B central region. Genotypic HCV prevalence was correlated with patient geographic location, sociodemographic, behavioral, lifestyle, and clinical factors. HCV genotype 4 was detected in 99.3% of the patients, while genotype 3 was identified in 0.7%. A total of eight (8) HCV subtypes were detected, with 4k being the predominant subtype nationwide (49.5%), followed by subtypes 4r (21.2%), 4q (16.2%), 4v (7.9%), 4b (2.0%), 4l (1.8%), 4c and 3h represent 0.7% each. Our findings reveal subtype distribution variations among provinces. Subtype 4k was prevalent across regions, particularly in Kigali (64.0%) and the Eastern Province (61.6%). Subtype 4q was more common in the northern province (40.7%), 4r in the southern (43.9%) and western provinces (37.1%), and 4v in the eastern province (17.8%). Farmers exhibit a distinct infection profile compared to other occupations, showing a lower prevalence of subtype 4k but a higher prevalence of subtype 4r. Our study revealed that HCV infection is unevenly distributed in Rwanda, dominated by HCV genotype 4, with considerable heterogeneity in the repartition of the different subtypes. We found potential associations between rural/urban lifestyles and HCV subtype profiles. Determined HCV distribution and diversity can serve as basis not only for HCV infection awareness and prevention campaigns, but also success and guidance for personalized treatment.

Outcome of intravenous thrombolysis in acute ischemic stroke patients with small vessel disease

IntroductionLacunar stroke (LS) subtype accounts for a quarter of ischemic strokes. Intravenous thrombolysis (IVT) is known to improve overall stroke outcomes. Very few studies have focused on the outcome of IVT in lacunar strokes. Aim: To detect the outcome of IVT in LS patients compared to non-thrombolysed LS patients. MethodsFifty patients presenting with LS received the standard protocol of IVT (Group I). They were compared to fifty matched LS patients who presented beyond the time window and were selected as the control group (Group II). Clinical outcome was measured using NIHSS within 24 h, NIHSS at discharge, and MRS after 3 months. Risk factors that could have affected clinical outcomes were compared in the thrombolysis group. ResultsThe short-term clinical outcome of Group I showed statistically significant improvement of NIHSS after 24 hrs compared to Group II (mean NIHSS = 5.52±3.89 and 7.44±1.82 respectively), as well as on discharge (mean NIHSS = 3.88±3.50 and 5.78±2.97) respectively. For long-term outcomes, 94 % of GroupⅠ reached MRS 0, 1, and 2 (n = 47/50) versus 74 % (n = 36/50) in Group II. Longer door-to-needle time, severe WMCs (Fazekas score), and pneumonia were shown to be significant predictor factors for the worst outcome. ConclusionIVT has improved short- and long-term outcomes in LS patients. Longer door-to-needle time, severe WMCs, and pneumonia were shown to be significant predictor factors for the worst outcome.

Adaptation and Validation of School Burnout Inventory-Bangla and Its Predictive Factors Among Adolescents.

School burnout (SB) among adolescents is a growing concern, yet there has been limited research in Bangladesh. This study aims to address this gap by validating the School Burnout Inventory (SBI) in Bangla and investigating the predictive factors of SB among high-school-going adolescents in Bangladesh. The study employed a cross-sectional design, recruiting participants from various high schools across urban and rural areas. Data were collected through self-reported questionnaires, which included information related to demographics, COVID-19, school burnout, daytime sleepiness, insomnia, and depression. The SBI-Bangla demonstrated high reliability and validity. The mean score of SB was 20.26 (±7.84). Significant differences in SB levels were observed across different age groups, grades, locations, mother's education levels, smoking status, and self-reported COVID-19 infection status. Multiple linear regression identified age (B = 0.647, p = .010), location (B = -1.043, p = .034), depression (B = 0.270, p < .001), daytime sleepiness (B = 0.208, p < .001), and insomnia (B = 0.662, p < .001) as significant predictors of SB. The final model explained 12.3% of the variance in SB scores. Enhancing sleep hygiene and addressing psychological issues may help reduce academic burnout. This study provides valuable baseline data that can inform future research and policy formulation aimed at reducing adolescent SB in Bangladesh.

Prevalence and Predictors of Complementary and Alternative Medicine Use Among Children Attending an Asthma Clinic in a Tertiary Hospital in Ghana

Objective: The objectives of this study were to determine the prevalence and type of CAMs, and predictive factors among Ghanaian children with asthma. Methodology: A cross-sectional study involving 110 children with physician-diagnosed asthma attending the Asthma Clinic of the Department of Child Health (DCH), Korle Bu Teaching Hospital (KBTH), Accra were consecutively recruited between February 2018 to May 2019. Data were collected with a semi-structured, pre-tested, investigator-administered questionnaire. Results: Out of the 110 participants, forty-nine (44.5%) had used CAM within the last 12 months. The three most frequently used remedies as standalone or in combination were honey (80.0%), garlic (34.2%) and lemon/lime (26.3%%). In the multivariable logistic regression analysis, CAM use among children aged 10--13 years was over 4 times the use among those aged 5--9 years (AOR=4.45, 95% CI: 1.32-14.98, p=0.016), 71% less among female children (AOR: 0.29, 95% CI: 0.10-0.80, p=0.017) and 85% less among mothers in middle occupation class relative to the low occupation class (AOR: 0.15, 95% CI: 0.15, 95% CI: 0.03-0.77, p=0.023). Conclusion: There was high prevalence of CAM use among the children attending the asthma clinic, KBTH. Adolescents and children from low occupational class are more likely to use CAM, while the female child was less likely.

Predictive Factors and Prognostic Relevance of Sunitinib-induced Subclinical and Overt Hypothyroidism in Korean Patients with Metastatic Renal Cell Carcinoma

Predictive Factors and Prognostic Relevance of Sunitinib-induced Subclinical and Overt Hypothyroidism in Korean Patients with Metastatic Renal Cell Carcinoma

Seroprevalence of Bordetella pertussis infection in children 1-14 years old: Indonesia basic health research (Riskesdas) 2013 and 2018 data.

Bordetella pertussis infection is a highly contagious respiratory disease that can cause complications such as pneumonia and death. A total of 62,646 cases of pertussis worldwide were reported by WHO in 2022. This study aimed to obtain the pertussis seroprevalence and sociodemographic data in children aged 1-14 years and its association factors in the community based on Riskesdas 2013 and 2018. Bivariate and multivariate analysis was carried out on data from 12,753 children aged 1-14 years collected from Riskesdas 2013 and 2018 in Indonesia. Pertussis serology data was obtained based on the results of the ELISA examination which was categorized as seropositive if anti-pertussis toxin IgG ≥ 100 IU/mL or anti-pertussis IgG > 11 NTU. Pertussis seropositive indicated recent pertussis infection if no pertussis vaccine was received within the last twelve months. Pertussis seroprevalence was found at 9.8% and 33.4% in Riskesdas 2013 and 2018 respectively. While 10.1% of children aged 5-14 years were found pertussis seropositive by excluding the possible effect of vaccination in the last twelve months in Riskesdas 2013. The most important associated factor in seropositive pertussis at ages 1-4 years and 5-14 years was a history of pneumonia in the last month (OR = 2.709, 95%CI: 2.592-2.831 in Riskesdas 2013 and OR = 2.421, 95%CI: 2.299-2.550 in Riskesdas 2018). In the adjusted analysis for respondents' characteristics, low maternal education was the predictive factor that most influenced pertussis seropositivity, especially in the 2013 Riskesdas (APOR = 2.983, 95%CI: 2.670-3.333). In conclusion, the results of this study showed that the seroprevalence of pertussis was high, especially in children aged 5-14 years, so that pertussis vaccine booster administration could be considered. Because the most influencing factor towards pertussis seropositive was low maternal education, the groups of children with low-educated mothers should be targets for strengthening complete vaccination coverage and disease control.

Early Urinary Potassium Level Predicts High-dose Methotrexate Elimination Delay in Primary Central Nervous System Lymphoma.

Treatment of primary central nervous system lymphoma (PCNSL) includes high dose methotrexate-based polychemotherapy (HD-MTX). This study aimed to identify early predictive factors of methotrexate (MTX) delayed elimination. We prospectively included all patients with newly-diagnosed PCNSL. Daily serum and urinary creatinine and ionogram were collected. We generated two independent cohorts: a training cohort (TC) and a confirmatory cohort (CC). We included for analysis 64 cures of HD-MTX (20 patients) in the TC and 59 cures (22 patients) in the CC. Median elimination time of MTX was 95 h and 96 h in the TC and CC, respectively. In multivariate analysis, older age (p=0.004), low Karnofsky Performance Status (p=0.036) and high urinary K+ (p=0.001) were associated with delayed MTX elimination. An optimal cutoff for urinary K+ was defined. In the CC, we confirmed that high urinary K+ (p=0.004) remained associated with delayed MTX elimination. High urinary K+ may be predictive of delayed MTX elimination in primary central nervous system lymphoma. Its relevance as a decision-making factor needs to be validated in additional prospective studies.