Benedikt Schaefer

Dr. Benedikt Schaefer

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 November 2020 in British Journal of Clinical Pharmacology
Verified
Journal Article
Open access
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BSBenedikt Schaefer
Benedikt Schaefer
MTMoritz Tobiasch
Moritz Tobiasch
AVAndré Viveiros
André Viveiros
HTHerbert Tilg
Herbert Tilg
NKNicholas A. Kennedy
Nicholas A. Kennedy
HZHeinz Zoller
Heinz Zoller
Aims: Hypophosphataemia is an increasingly recognized side‐effect of ferric carboxymaltose (FCM) and possibly iron isomaltoside/ferric derisomaltose (IIM), which are used to treat iron deficiency. The aim of this study was to determine frequency, severity, duration and risk factors of incident hypophosphataemia after treatment with FCM and IIM.Methods: A systematic literature search for articles indexed in EMBASE, PubMed and Web of Science in years 2005–2020 was carried out using the search terms ‘ferric carboxymaltose’ OR ‘iron isomaltoside’. Prospective clinical trials reporting outcomes on hypophosphataemia rate, mean nadir serum phosphate and/or change in mean serum phosphate from baseline were selected. Hypophosphataemia rate and severity were compared for studies on IIM vs. FCM after stratification for chronic kidney disease. Meta‐regression analysis was used to investigate risk factors for hypophosphataemia.Results: Across the 42 clinical trials included in the meta‐analysis, FCM induced a significantly higher incidence of hypophosphataemia than IIM (47%, 95% CI 36–58% vs. 4%, 95% CI 2–5%), and significantly greater mean decreases in serum phosphate (0.40 vs. 0.06 mmol/L). Hypophosphataemia persisted at the end of the study periods (maximum 3 months) in up to 45% of patients treated with FCM. Meta‐regression analysis identified low baseline serum ferritin and transferrin saturation, and normal kidney function as significant predictors of hypophosphataemia.Conclusion: FCM is associated with a high risk of hypophosphataemia, which does not resolve for at least 3 months in a large proportion of affected patients. More severe iron deficiency and normal kidney function are risk factors for hypophosphataemia.

18 January 2022 in PLOS Digital Health
Verified
Journal Article
Open access
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VDVadim Demichev
Vadim Demichev
PTPinkus Tober-Lau
Pinkus Tober-Lau
TNTatiana Nazarenko
Tatiana Nazarenko
OLOliver Lemke
Oliver Lemke
SASimran Kaur Aulakh
Simran Kaur Aulakh
MRMarkus Ralser
Markus Ralser
Global healthcare systems are challenged by the COVID-19 pandemic. There is a need to optimize allocation of treatment and resources in intensive care, as clinically established risk assessments such as SOFA and APACHE II scores show only limited performance for predicting the survival of severely ill COVID-19 patients. Additional tools are also needed to monitor treatment, including experimental therapies in clinical trials. Comprehensively capturing human physiology, we speculated that proteomics in combination with new data-driven analysis strategies could produce a new generation of prognostic discriminators. We studied two independent cohorts of patients with severe COVID-19 who required intensive care and invasive mechanical ventilation. SOFA score, Charlson comorbidity index, and APACHE II score showed limited performance in predicting the COVID-19 outcome. Instead, the quantification of 321 plasma protein groups at 349 timepoints in 50 critically ill patients receiving invasive mechanical ventilation revealed 14 proteins that showed trajectories different between survivors and non-survivors. A predictor trained on proteomic measurements obtained at the first time point at maximum treatment level (i.e. WHO grade 7), which was weeks before the outcome, achieved accurate classification of survivors (AUROC 0.81). We tested the established predictor on an independent validation cohort (AUROC 1.0). The majority of proteins with high relevance in the prediction model belong to the coagulation system and complement cascade. Our study demonstrates that plasma proteomics can give rise to prognostic predictors substantially outperforming current prognostic markers in intensive care.

10 April 2023 in Liver Transplantation
Verified
Journal Article
Closed access
BTBenjamin V. Tran
Benjamin V. Tran
DMDimitrios Moris
Dimitrios Moris
DMDaniela Markovic
Daniela Markovic
HZHamed Zaribafzadeh
Hamed Zaribafzadeh
RHRicardo Henao
Ricardo Henao
VAVatche G. Agopian
Vatche G. Agopian
HCC recurrence following liver transplantation (LT) is highly morbid and occurs despite strict patient selection criteria. Individualized prediction of post-LT HCC recurrence risk remains an important need. Clinico-radiologic and pathologic data of 4981 patients with HCC undergoing LT from the US Multicenter HCC Transplant Consortium (UMHTC) were analyzed to develop a REcurrent Liver cAncer Prediction ScorE (RELAPSE). Multivariable Fine and Gray competing risk analysis and machine learning algorithms (Random Survival Forest and Classification and Regression Tree models) identified variables to model HCC recurrence. RELAPSE was externally validated in 1160 HCC LT recipients from the European Hepatocellular Cancer Liver Transplant study group. Of 4981 UMHTC patients with HCC undergoing LT, 71.9% were within Milan criteria, 16.1% were initially beyond Milan criteria with 9.4% downstaged before LT, and 12.0% had incidental HCC on explant pathology. Overall and recurrence-free survival at 1, 3, and 5 years was 89.7%, 78.6%, and 69.8% and 86.8%, 74.9%, and 66.7%, respectively, with a 5-year incidence of HCC recurrence of 12.5% (median 16 months) and non-HCC mortality of 20.8%. A multivariable model identified maximum alpha-fetoprotein (HR = 1.35 per-log SD, 95% CI,1.22–1.50, p < 0.001), neutrophil-lymphocyte ratio (HR = 1.16 per-log SD, 95% CI,1.04–1.28, p < 0.006), pathologic maximum tumor diameter (HR = 1.53 per-log SD, 95% CI, 1.35–1.73, p < 0.001), microvascular (HR = 2.37, 95%–CI, 1.87–2.99, p < 0.001) and macrovascular (HR = 3.38, 95% CI, 2.41–4.75, p < 0.001) invasion, and tumor differentiation (moderate HR = 1.75, 95% CI, 1.29–2.37, p < 0.001; poor HR = 2.62, 95% CI, 1.54–3.32, p < 0.001) as independent variables predicting post-LT HCC recurrence (C-statistic = 0.78). Machine learning algorithms incorporating additional covariates improved prediction of recurrence (Random Survival Forest C-statistic = 0.81). Despite significant differences in European Hepatocellular Cancer Liver Transplant recipient radiologic, treatment, and pathologic characteristics, external validation of RELAPSE demonstrated consistent 2- and 5-year recurrence risk discrimination (AUCs 0.77 and 0.75, respectively). We developed and externally validated a RELAPSE score that accurately discriminates post-LT HCC recurrence risk and may allow for individualized post-LT surveillance, immunosuppression modification, and selection of high-risk patients for adjuvant therapies.

18 April 2019 in JCI Insight
Verified
Journal Article
Open access
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DHDavid Haschka
David Haschka
VPVerena Petzer
Verena Petzer
FKFlorian Kocher
Florian Kocher
CTChristoph Tschurtschenthaler
Christoph Tschurtschenthaler
BSBenedikt Schaefer
Benedikt Schaefer
PTPiotr Tymoszuk
Piotr Tymoszuk
Myelomonocytic cells are critically involved in iron turnover as aged RBC recyclers. Human monocytes are divided in 3 subpopulations of classical, intermediate, and nonclassical cells, differing in inflammatory and migratory phenotype. Their functions in iron homeostasis are, however, unclear. Here, we asked whether the functional diversity of monocyte subsets translates into differences in handling physiological and pathological iron species. By microarray data analysis and flow cytometry we identified a set of iron-related genes and proteins upregulated in classical and, in part, intermediate monocytes. These included the iron exporter ferroportin (FPN1), ferritin, transferrin receptor, putative transporters of non-transferrin-bound iron (NTBI), and receptors for damaged erythrocytes. Consequently, classical monocytes displayed superior scavenging capabilities of potentially toxic NTBI, which were augmented by blocking iron export via hepcidin. The same subset and, to a lesser extent, the intermediate population, efficiently cleared damaged erythrocytes in vitro and mediated erythrophagocytosis in vivo in healthy volunteers and patients having received blood transfusions. To summarize, our data underline the physiologically important function of the classical and intermediate subset in clearing NTBI and damaged RBCs. As such, these cells may play a nonnegligible role in iron homeostasis and limit iron toxicity in iron overload conditions.

23 February 2018 in Liver Transplantation
Verified
Journal Article
Open access
PDF file
AVAndré Viveiros
André Viveiros
AFArmin Finkenstedt
Armin Finkenstedt
BSBenedikt Schaefer
Benedikt Schaefer
MMMattias Mandorfer
Mattias Mandorfer
BSBernhard Scheiner
Bernhard Scheiner
HZHeinz Zoller
Heinz Zoller
Patients with cirrhosis frequently present with high serum ferritin and low transferrin concentrations, reflecting impaired liver function and inflammation. Recent studies have shown that transferrin and its saturation with iron are Model for End‐Stage Liver Disease–independent predictors of mortality in patients with acute‐on‐chronic liver failure or decompensated cirrhosis. The aim of this study was to evaluate the prognostic utility of serum iron parameters in relation to markers of liver function and immune activation. Clinical, demographic, and biochemical data were retrospectively analyzed from a cohort of 1255 consecutive patients with cirrhosis (age ≥ 18 years) who presented from August 1, 2004 until December 31, 2014 at the University Hospital of Innsbruck. Patients with malignancies at diagnosis including hepatocellular carcinoma were excluded. Survival analysis was carried out by Cox regression by using baseline laboratory parameters, and findings were validated in an independent patient cohort. During a median follow‐up of 2.4 years, 193 deaths occurred and 254 patients underwent liver transplantation. In patients with transferrin < 180 mg/dL, 3‐month, 1‐year, and 5‐year transplant‐free survival estimates were significantly lower (91.7%, 79.0%, and 30.5%) when compared with the group of patients with transferrin ≥ 180 mg/dL (98.9%, 95.5%, and 68.0%, P < 0.001). Transferrin predicted transplant‐free survival independently of Model for End‐Stage Liver Disease–sodium (MELD‐Na) and C‐reactive protein (CRP) in multivariate regression analysis including all patients. When patients with alcoholic or nonalcoholic fatty liver disease were excluded, transferrin was in addition an albumin‐independent predictor of transplant‐free survival. In conclusion, the association of transferrin with transplant‐free survival is independent of MELD‐Na score and CRP. In patients without fatty liver disease, transferrin also predicts survival independently of albumin. Liver Transplantation 24 343–351 2018 AASLD.

29 June 2018 in Alimentary Pharmacology & Therapeutics
Verified
Journal Article
Open access
PDF file
MMM. Mandorfer
M. Mandorfer
BSbernhard scheiner
bernhard scheiner
ASA. F. Stättermayer
A. F. Stättermayer
PSPhilipp Schwabl
Philipp Schwabl
RPR. Paternostro
R. Paternostro
AFA. Ferlitsch
A. Ferlitsch
Summary: Background: The rs738409 C>G p.I148M variant in the patatin‐like phospholipase domain containing 3 (PNPLA3)‐gene promotes triglyceride accumulation in hepatocytes and hepatic stellate cell activation and has previously been linked to hepatic steatosis/liver fibrosis.Aim: To investigate its impact on hepatic decompensation and (liver‐related) mortality in patients who had already developed portal hypertension. Moreover, we assessed its link with hepatic steatosis as evaluated by controlled attenuation parameter.Methods: We performed a retrospective analysis in prospectively characterised patients with viral hepatitis/fatty liver disease‐induced portal hypertension (hepatic venous pressure gradient [HVPG] ≥ 6 mm Hg) diagnosed at the Medical University of Vienna who underwent HVPG measurement (until 2013; n = 372; longitudinal study) or simultaneous HVPG and controlled attenuation parameter measurement (2014‐2017; n = 153; cross‐sectional study).Results: While survival was similar between PNPLA3‐C/C and ‐C/G patients, we observed substantially increased mortality in PNPLA3‐G/G patients. PNPLA3‐G/G had no impact on mortality in the subgroup of patients with viral hepatitis; however, we observed a strong independent association between PNPLA3‐G/G and hepatic decompensation (adjusted subdistribution hazard ratio [aSHR]: 2.1, 95% confidence interval [95% CI]: 1.1‐4; P = 0.024) as well as mortality (overall: aSHR: 2.2, 95% CI: 1.22‐3.98; P = 0.009; liver‐related: aSHR: 2.2, 95% CI: 1.08‐4.46; P = 0.029) in patients with fatty liver disease. Interestingly, even in the subgroup of patients who had already progressed to clinically significant portal hypertension (HVPG ≥ 10 mm Hg), PNPLA3‐G/G substantially increased mortality (aSHR: 2.33, 95% CI: 1.27‐4.29; P = 0.006). PNPLA3‐genotype had no influence on controlled attenuation parameter or the prevalence of values ≥248 dB/m.Conclusion: PNPLA3‐G/G‐genotype seems to double the risks of hepatic decompensation and (liver‐related) mortality in patients with portal hypertension due to fatty liver disease. Further studies are warranted to investigate potential underlying pathophysiological mechanisms unrelated to hepatic steatosis.