Betty van Aken, Jens-Michalis Papaioannou, Marcel Naik, Georgios Eleftheriadis, Wolfgang Nejdl, Felix Gers, Alexander Loeser. Proceedings of the 2nd Conference of the Asia-Pacific Chapter of the Association for Computational Linguistics and the 12th International Joint Conference on Natural Language Processing (Volume 1: Long Papers). 2022.

Kidney transplant recipients (KTRs) show higher morbidity and mortality from COVID-19 than the general population and have an impaired response to vaccination. We analyzed COVID-19 incidence and clinical outcomes in a single-center cohort of approximately 2500 KTRs. Between 1 February 2020 and 1 July 2022, 578 KTRs were infected with SARS-CoV-2, with 25 (4%) recurrent infections. In total, 208 KTRs (36%) were hospitalized, and 39 (7%) died. Among vaccinated patients, infection with the Omicron variant had a mortality of 2%. Unvaccinated patients infected with the Omicron variant showed mortality (9% vs. 11%) and morbidity (hospitalization 52% vs. 54%, ICU admission 12% vs. 18%) comparable to the pre-Omicron era. Multivariable analysis revealed that being unvaccinated (OR = 2.15, 95% CI [1.38, 3.35]), infection in the pre-Omicron era (OR = 3.06, 95% CI [1.92, 4.87]), and higher patient age (OR = 1.04, 95% CI [1.03, 1.06]) are independent risk factors for COVID-19 hospitalization, whereas a steroid-free immunosuppressive regimen was found to reduce the risk of COVID-19 hospitalization (OR = 0.51, 95% CI [0.33, 0.79]). This suggests that both virological changes in the Omicron variant and vaccination reduce the risk for morbidity and mortality from COVID-19 in KTRs. Our data extend the knowledge from the general population to KTRs and provide important insights into outcomes during the Omicron era.

Background: The aim of this study was to quantify hypertension control and evaluate concordance between all commonly available blood pressure (BP) modalities in kidney transplant recipients (KTRs). Methods: For this prospective cross-sectional study, 89 stable KTRs were recruited at the Charité Transplant Outpatient Clinic. For each study participant office [manual office BP (MOBP) and automated office BP (AOBP)], 7-day home (HBPM) and 24-hour ambulatory BP (24h-ABPM) measurements were performed. Results: 80 of the 89 patients recruited had sufficient BP recordings. The mean BP for MOBP, AOBP, HBPM and 24h-ABPM was 129/73, 126/71, 131/85 and 130/81 mmHg, respectively. Uncontrolled hypertension, as defined by 24h-ABPM (mean ≥130/80 mmHg), was present in 53 (66%) patients. MOBP, AOBP and HBPM classified 19 (24%), 22 (28%) and 41 (51%) patients, respectively, as ‘uncontrolled hypertensive’. The Bland–Altman plot showed good agreement between systolic MOBP, AOBP, HBPM and daytime-ABPM (mean bias: −1 ± 13 mmHg, −4 ± 13 mmHg, 1 ± 10 mmHg, respectively). Uncontrolled night-time hypertension was present in 74 (93%) KTRs, with 71 (89%) patients showing a non-physiological dipping pattern. Moderate positive correlation between daytime-ABPM/HBPM and night-time-ABPM (Pearson correlation coefficients: 0.62–0.73), followed by MOBP/AOBP (Pearson correlation coefficients: 0.49–0.59) was noted. Estimated eGFR and proteinuria displayed weak correlation with 24h-, daytime- and night-time-ABPM (absolute values of Pearson correlation coefficients: 0.04–0.41). No robust association with either 24h-, daytime- or night-time-ABPM was observed for volume status exams. Conclusions: Masked hypertension is highly prevalent in KTRs, especially due to high rates of uncontrolled night-time hypertension. HBPM shows the narrowest limits of agreement with daytime-ABPM. Daytime-ABPM and HBPM show the highest, albeit clinically insufficient, correlation with night-time-ABPM. Systematic integration of 24h-ABPM into clinical practice, as proposed by the 2023 ESH guidelines for the management of arterial hypertension, should not be withheld for the KTR population. Clinical trials evaluating the treatment of hypertension in KTRs are urgently needed.

Introduction: In renal transplant recipients (RTRs), kidney graft failure and cardiovascular (CV) disease are prevalent and associated with mortality. Objectives: The objective of the study was to evaluate biomarkers, (cardiac troponin T (cTnT) and N-terminal pro-B-type natriuretic peptide (NT-proBNP)), to identify RTRs who are at greater risk of death, CV event, and graft renal survival. Patients and methods: A total of 342 stable RTRs were enrolled in this study, with a median follow-up time of 54 months. The probability of death, CV event, and renal graft survival were calculated using Kaplan–Meier analysis for the group defined by cTnT and NT-proBNP levels above the cutoff values. Results: The probability of death for troponin T level above the cut-off was 23% and for NT-proBNP 29%. For CV events the probability for troponin T was 20% and for NT-proBNP it was 21%. Troponin T concentrations above the cutoff point suggested a 25% probability of death-censored graft survival. For NT-proBNP, it was 26%. The probability of overall graft survival was 38% for patients with higher troponin T levels, and 40% for NT proBNP. Conclusions: These data suggest that cTnT and NT-proBNP could potentially identify patients at high risk for death, CV event, and graft survival.

Post-transplantation diabetes mellitus (PTDM) and prediabetes are associated with increased cardiovascular morbidity and mortality in kidney transplant recipients (KTR), when diagnosed by an oral glucose tolerance test (oGTT). Hemoglobin A1c (HbA1c) and fasting plasma glucose (FPG) display low concordance with the oGTT in the early phase posttransplant. For this prospective cross-sectional pilot study, 41 KTR from years one to five after transplantation without known preexisting PTDM (defined by HbA1c ≥ 6.5% (NGSP) or 48 mmol/mol (IFCC) at last visit or glucose-lowering therapy) were recruited at the Charité Transplant Outpatient Clinic. For each study participant HbA1c, FPG and an oGTT were followed by CGM. 38 of the 41 patients recruited had sufficient CGM-recordings (≥10 days). PTDM and impaired glucose tolerance (IGT), as defined by the gold standard oral glucose tolerance test (oGTT)-derived 2-h plasma glucose (2hPG), were diagnosed in one (3%) and twelve (32%) patients, respectively. HbA1c exhibited good test characteristics regarding IGT (ROC-AUC: 0.87); sensitivity/specificity of HbA1c-threshold 5.7% (NGSP) or 39 mmol/mol (IFCC) were 1.0/0.64, respectively. Best performing CGM-readouts mean sensor glucose and percent of time >140 mg/dL (%TAR (140 mg/dL)) displayed acceptable diagnostic performance (ROC-AUC: 0.78 for both). Thus, HbA1c can aid in timely diagnosis of IGT in the stable phase after kidney transplantation.