PHENOTYPING REPAIR AFTER ACUTE KIDNEY INJURY: PRECISION MEDICINE TO CLINICAL TRIALS.

Acute kidney injury (AKI) is common during hospitalization and is associated with long-term risk of readmissions and chronic kidney disease (CKD). Preclinical studies and novel urine biomarkers have demonstrated that subclinical inflammation and repair continue for several months after AKI. We conducted three clinical and translational studies to alleviate long-term sequelae after AKI. First, we assessed repair in deceased donor kidneys which can assist with organ allocation and reduce discard. In an ongoing study, organ procurement organizations are measuring repair biomarkers via lateral flow devices to assess organ quality and adding it to their workflow. Second, we performed research biopsies during AKI to interrogate kidney tissue with novel transcriptomic and proteomic techniques to advance therapeutic development. Third, we initiated pragmatic clinical trials to reduce readmissions after an episode of AKI by providing nurse navigator and pharmacist support to optimize blood pressure, fluid, and medication management.

Urine Biomarkers of Kidney Tubule Health and Risk of Incident CKD in Persons Without Diabetes: The ARIC, MESA, and REGARDS Studies.

Rationale & Objective: Tubulointerstitial damage is a feature of early chronic kidney disease (CKD), but current clinical tests capture it poorly. Urine biomarkers of tubulointerstitial health may identify risk of CKD. Study Design: Prospective cohort (Atherosclerosis Risk in Communities [ARIC]) and case-cohort (Multi-Ethnic Study of Atherosclerosis [MESA] and Reasons for Geographic and Racial Differences in Stroke [REGARDS]). Setting & Participants: Adults with estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2 and without diabetes in the ARIC, REGARDS, and MESA studies. Exposures: Baseline urine monocyte chemoattractant protein-1 (MCP-1), alpha-1-microglobulin (α1m), kidney injury molecule-1, epidermal growth factor, and chitinase-3-like protein 1. Outcome: Incident CKD or end-stage kidney disease. Analytical Approach: Multivariable Cox proportional hazards regression for each cohort; meta-analysis of results from all 3 cohorts. Results: 872 ARIC participants (444 cases of incident CKD), 636 MESA participants (158 cases), and 924 REGARDS participants (488 cases) were sampled. Across cohorts, mean age ranged from 60 ± 10 to 63 ± 8 years, and baseline eGFR ranged from 88 ± 13 to 91 ± 14 mL/min/1.73 m2. In ARIC, higher concentrations of urine MCP-1, α1m, and kidney injury molecule-1 were associated with incident CKD. In MESA, higher concentration of urine MCP-1 and lower concentration of epidermal growth factor were each associated with incident CKD. In REGARDS, none of the biomarkers were associated with incident CKD. In meta-analysis of all 3 cohorts, each 2-fold increase α1m concentration was associated with incident CKD (HR, 1.19; 95% CI, 1.08-1.31). Limitations: Observational design susceptible to confounding; competing risks during long follow-up period; meta-analysis limited to 3 cohorts. Conclusions: In 3 combined cohorts of adults without prevalent CKD or diabetes, higher urine α1m concentration was independently associated with incident CKD. 4 biomarkers were associated with incident CKD in at least 1 of the cohorts when analyzed individually. Kidney tubule health markers might inform CKD risk independent of eGFR and albuminuria.

This study analyzed 3 cohorts (ARIC, MESA, and REGARDS) of adults without diabetes or prevalent chronic kidney disease (CKD) to determine the associations of 5 urinary biomarkers of kidney tubulointerstitial health with incident CKD, independent of traditional measures of kidney health. Meta-analysis of results from all 3 cohorts suggested that higher baseline levels of urine alpha-1-microglobulin were associated with incident CKD at follow-up. Results from individual cohorts suggested that in addition to alpha-1-microglobulin, monocyte chemoattractant protein-1, kidney injury molecule-1, and epidermal growth factor may also be associated with the development of CKD. These findings underscore the importance of kidney tubule interstitial health in defining risk of CKD independent of creatinine and urine albumin.

Kidney Transplant Outcomes From Deceased Donors Who Received Dialysis.

Importance: Recipient outcomes after kidney transplant from deceased donors who received dialysis prior to kidney donation are not well described. Objective: To compare outcomes of transplant recipients who received kidneys from deceased donors who underwent dialysis prior to kidney donation vs recipients of kidneys from deceased donors who did not undergo dialysis. Design, Setting, and Participants: A retrospective cohort study was conducted including data from 58 US organ procurement organizations on deceased kidney donors and kidney transplant recipients. From 2010 to 2018, 805 donors who underwent dialysis prior to kidney donation were identified. The donors who underwent dialysis prior to kidney donation were matched 1:1 with donors who did not undergo dialysis using a rank-based distance matrix algorithm; 1944 kidney transplant recipients were evaluated. Exposure: Kidney transplants from deceased donors who underwent dialysis prior to kidney donation compared with kidney transplants from deceased donors who did not undergo dialysis. Main Outcomes and Measures: The 4 study outcomes were delayed graft function (defined as receipt of dialysis by the kidney recipient ≤1 week after transplant), all-cause graft failure, death-censored graft failure, and death. Results: From 2010 to 2018, 1.4% of deceased kidney donors (805 of 58 155) underwent dialysis prior to kidney donation. Of these 805 individuals, 523 (65%) donated at least 1 kidney. A total of 969 kidneys (60%) were transplanted and 641 kidneys (40%) were discarded. Among the donors with kidneys transplanted, 514 (mean age, 33 years [SD, 10.8 years]; 98 had hypertension [19.1%] and 36 had diabetes [7%]) underwent dialysis prior to donation and were matched with 514 (mean age, 33 years [SD, 10.9 years]; 98 had hypertension [19.1%] and 36 had diabetes [7%]) who did not undergo dialysis. Kidney transplants from donors who received dialysis prior to donation (n = 954 kidney recipients) were associated with a higher risk of delayed graft function compared with kidney transplants from donors who did not receive dialysis (n = 990 kidney recipients) (59.2% vs 24.6%, respectively; adjusted odds ratio, 4.17 [95% CI, 3.28-5.29]). The incidence rates did not significantly differ at a median follow-up of 34.1 months for all-cause graft failure (43.1 kidney transplants per 1000 person-years from donors who received dialysis prior to donation vs 46.9 kidney transplants per 1000 person-years from donors who did not receive dialysis; adjusted hazard ratio [HR], 0.90 [95% CI, 0.70-1.15]), for death-censored graft failure (22.5 vs 20.6 per 1000 person-years, respectively; adjusted HR, 1.18 [95% CI, 0.83-1.69]), or for death (24.6 vs 30.8 per 1000 person-years; adjusted HR, 0.76 [95% CI, 0.55-1.04]). Conclusions and Relevance: Compared with receiving a kidney from a deceased donor who did not undergo dialysis, receiving a kidney from a deceased donor who underwent dialysis prior to kidney donation was associated with a significantly higher incidence of delayed graft function, but no significant difference in graft failure or death at follow-up.

MASLD and MASH at the crossroads of hepatology trials and cardiorenal metabolic trials.

Steatotic liver disease (SLD) is a worldwide public health problem, causing considerable morbidity and mortality. Patients with SLD are at increased risk for major adverse cardiovascular (CV) events, type 2 diabetes mellitus and chronic kidney disease. Conversely, patients with cardiometabolic conditions have a high prevalence of SLD. In addition to epidemiological evidence linking many of these conditions, there is evidence of shared pathophysiological processes. In December 2022, a unique multi-stakeholder, multi-specialty meeting, called MOSAIC (Metabolic multi Organ Science Accelerating Innovation in Clinical Trials) was convened to foster collaboration across metabolic, hepatology, nephrology and CV disorders. One of the goals of the meeting was to consider approaches to drug development that would speed regulatory approval of treatments for multiple disorders by combining liver and cardiorenal endpoints within a single study. Non-invasive tests, including biomarkers and imaging, are needed in hepatic and cardiorenal trials. They can be used as trial endpoints, to enrich trial populations, to diagnose and risk stratify patients and to assess treatment efficacy and safety. Although they are used in proof of concept and phase 2 trials, they are often not acceptable for regulatory approval of therapies. The challenge is defining the optimal combination of biomarkers, imaging and morbidity/mortality outcomes and ensuring that they are included in future trials while minimizing the burden on patients, trialists and trial sponsors. This paper provides an overview of some of the wide array of CV, liver and kidney measurements that were discussed at the MOSAIC meeting.

The development of lateral flow devices for urinary biomarkers to assess kidney health.

Serum creatinine levels are insensitive to real-time changes in kidney function or injury. There is a growing interest in assessing kidney injury by measuring biomarkers in body fluid. From our previous studies, we identified and reported three urinary biomarkers namely Uromodulin (UMOD), Osteopontin (OPN), and Interleukin-9 (IL-9) to be associated with kidney health. The availability of a rapid point-of-care test for these urinary biomarkers will potentially accelerate its applicability and accessibility. In this study, we aimed to develop novel lateral flow device (LFD) for UMOD, OPN and IL-9. We tested paired antibodies using Enzyme Linked Immunosorbent Assay wherein we observed functionality only for UMOD and OPN and not for IL-9. A conjugation buffer pH of 7.8 and 8.5 was found suitable at a detection antibody concentration of 15 µg/mL for LFD development. The developed LFDs were found to quantitatively measure UMOD standard (LLOD of 80,000 pg/mL) and OPN standard (LLOD of 8600 pg/mL) respectively. The LFD was also able to measure human urinary UMOD and OPN with a percent CV of 12.12 and 5.23 respectively.

Mitochondrial genetic variation and risk of chronic kidney disease and acute kidney injury in UK Biobank participants.

Experimental models suggest an important role for mitochondrial dysfunction in the pathogenesis of chronic kidney disease (CKD) and acute kidney injury (AKI), but little is known regarding the impact of common mitochondrial genetic variation on kidney health. We sought to evaluate associations of inherited mitochondrial DNA (mtDNA) variation with risk of CKD and AKI in a large population-based cohort. We categorized UK Biobank participants who self-identified as white into eight distinct mtDNA haplotypes, which were previously identified based on their associations with phenotypes associated with mitochondrial DNA copy number, a measure of mitochondrial function. We used linear and logistic regression models to evaluate associations of these mtDNA haplotypes with estimated glomerular filtration rate by serum creatinine and cystatin C (eGFRCr-CysC, N = 362,802), prevalent (N = 416 cases) and incident (N = 405 cases) end-stage kidney disease (ESKD), AKI defined by diagnostic codes (N = 14,170 cases), and urine albumin/creatinine ratio (ACR, N = 114,662). The mean age was 57 ± 8 years and the mean eGFR was 90 ± 14 ml/min/1.73 m2. MtDNA haplotype was significantly associated with eGFR (p = 2.8E-12), but not with prevalent ESKD (p = 5.9E-2), incident ESKD (p = 0.93), AKI (p = 0.26), or urine ACR (p = 0.54). The association of mtDNA haplotype with eGFR remained significant after adjustment for diabetes mellitus and hypertension (p = 1.2E-10). When compared to the reference haplotype, mtDNA haplotypes I (ß = 0.402, standard error (SE) = 0.111; p = 2.7E-4), IV (ß = 0.430, SE = 0.073; p = 4.2E-9), and V (ß = 0.233, SE = 0.050; p = 2.7E-6) were each associated with higher eGFR. Among self-identified white UK Biobank participants, mtDNA haplotype was associated with eGFR, but not with ESKD, AKI or albuminuria.

Implementation of the Kidney Failure Risk Equation in a United States Nephrology Clinic.

Introduction: The kidney failure risk equation (KFRE) estimates a person's risk of kidney failure and has great potential utility in clinical care. Methods: We used mixed methods to explore implementation of the KFRE in nephrology clinics. Results: KFRE scores were integrated into the electronic health record at Johns Hopkins Medicine and were displayed to nephrology providers. Documentation of KFRE scores increased over time, reaching 25% of eligible outpatient nephrology clinic notes at month 11. Three providers documented KFRE scores in >75% of notes, whereas 25 documented scores in <10% of notes. Surveys and focus groups of nephrology providers were conducted to probe provider views on the KFRE. Survey respondents (n = 25) reported variability in use of KFRE for decisions such as maintaining nephrology care, referring for transplant evaluation, or providing dialysis modality education. Provider perspectives on the use of KFRE, assessed in 2 focus groups of 4 providers each, included 3 common themes as follows: (i) KFRE scores may be most impactful in the care of specific subsets of people with chronic kidney disease (CKD); (ii) there is uncertainty about KFRE risk-based thresholds to guide clinical care; and (iii) education of patients, nephrology providers, and non-nephrology providers on appropriate interpretations of KFRE scores may help maximize their utility. Conclusion: Implementation of the KFRE was limited by non-uniform provider adoption of its use, and limited knowledge about utilization of the KFRE in clinical decisions.

Indicators and predictors of in-hospital mortality and survival in patients with ventricular septal rupture.

Background: Ventricular septal rupture (VSR), a mechanical complication of myocardial infarction (MI), usually presents with rapid clinical deterioration with acute heart failure or cardiogenic shock. VSR may occur within 24 h to several days after MI and can occur in both anterior and inferior wall MI. Although guidelines recommend emergent surgery, this is associated with a high mortality rate of up to 40%. Intra-aortic balloon pump (IABP) and extracorporeal membrane oxygenation (ECMO) stabilize patients in preparation for angiography and surgery. Delayed surgery allows better septal repair in scarring tissue but also carries the risk of rupture extension and death while waiting. Percutaneous closure of the defect with appropriately designed devices results in better survival in the subacute phase. Aims: To study the indicators and predictors of VSR in the current era of primary percutaneous coronary interventions and mechanical circulatory support. Methods: Of total of 34,681 patients presenting with MI, the incidence of VSR was 0.45%. We sought to evaluate the predictors of survival and death in VSR. Coronary angiography (CAG) was performed, hemodynamic support provided to unstable patients, and consenting patients were referred to definitive therapy, either surgery or percutaneous device closure. The previously postulated hypotheses of triple vessel disease (TVD), diabetes mellitus (DM), and concentric left ventricular hypertrophy (LVH) due to Hypertension (HTN) being protective against VSR were explored. Results: Of the 169 patients with VSR, we found that the group that survived was mostly men and the mean age was 61.5 years; this was in contrast to the non-survivors, who were mainly women, and the mean age was 65.2 years (p = 0.025); higher Killip Class was 111-1V (p = 0.001), lower LVEF (p = 0.010), apical VSR and LV aneurysm (p = 0.015 and p = 0.002, respectively) were predictors of death. 48 patients underwent CAG, with single vessel disease (SVD) with lower-grade Rentrop collateral flow being most common in the death group. 25 patients were subjected to definitive therapy with surgical patch closure or percutaneous device closure. The patients who died were older by approximately 7 years. The risk factors for coronary artery disease, such as HTN, diabetes, and smoking, were not statistically different between the two groups. Conclusion: Prevention of myocardial infarction is more important than managing a VSR, which carries a high mortality despite advanced mechanical support and definitive interventional therapy such as emergent surgery and percutaneous device closure.

Warfarin use has no effect on blood pressure of patients with Diabetes and hypertension / Uso da warfarina não tem efeitos sobre a pressão arterial em pacientes com diabetes e hipertensão arterial sistêmica

Introduction: Warfarin causes arterial calcification, arterial stiffness and systolic hypertension in animals. Early evidence in humans indicates that a similar effect may occur in patients with diabetes mellitus (DM) and/or hypertension. Objective: To evaluate whether warfarin use causes elevated blood pressure and pulse pressure in patients with both DM and hypertension. Methods: Cross-sectional study of 159 subjects with both DM and hypertension who received warfarin for at least 2 years and 159 age-matched control subjects with DM and hypertension never exposed to warfarin. The primary focus of analysis was the difference in systolic blood pressure (SBP), diastolic blood pressure (DBP) and pulse pressure (PP) between the two groups. Results: Average age was 73±10 years in both groups. Patients in the warfarin group had received it for an average of 5.5±3.1 years. Subjects in the warfarin group had higher rates of coronary disease and heart failure. SBP and PP were lower in the warfarin group (SBP 130±14 mmHg vs. 134±12 mmHg, P=0.003; PP 58±12 mmHg vs. 62±11 mmHg, P=0.004), while DBP was not different (72±8 vs. 72±7 mmHg, P=0.64). Warfarin patients received more antihypertensive drugsand were seen more often than controls. Multiple regression analyses adjusting for relevant variables did not disclose an association between warfarin useand higher BP; on the contrary, exposure to warfarin was associated with lower SBP and PP on the multivariable models. Conclusion: Use of warfarin in conventional doses for an average of 5.5 years was not associated with increased BP in this cross-sectional study of patients with DM and hypertension.

Introdução: Em animais, a warfarina provoca calcificação arterial, rigidez arterial e hipertensão arterial (HA) sistólica. Dados preliminares em humanos sugerem que o mesmo efeito pode acontecer em pacientes com diabetes mellitus (DM) e/ou HA. Objetivo: Determinar se o uso da warfarina em pacientescom DM e HA resulta em elevação da pressão arterial ou pressão de pulso. Métodos: Estudo transversal de 159 pacientes com DM e HA que haviam sidotratados com warfarina por pelo menos 2 anos, e 159 controles pareados por idade, com DM e HA, mas que nunca haviam usado warfarina. O enfoqueprincipal na análise foi a diferença na pressão arterial sistólica (PAS), diastólica (PAD) e pressão de pulso (PP) entre os dois grupos. Resultados: A média de idade foi 73±10 anos em ambos os grupos. Os pacientes no grupo da warfarina haviam usado a droga por 5.5±3.1 anos. Pacientes no grupo da warfarina tinham uma prevalência maior de doença coronariana e insuficiência cardíaca. A PAS e PP foram mais baixas no grupo warfarina (PAS 130±14 mmHgvs. 134±12 mmHg, P=0.003; PP 58±12 mmHg vs. 62±11 mmHg, P=0.004), mas a PAD não diferiu entre os grupos (72±8 vs. 72±7 mmHg, P=0.64).Pacientes do grupo warfarina usaram mais drogas antihipertensivas e foram avaliados clinicamente com maior freqüência do que os controles. Regressão múltipla ajustada para fatores de relevância clínica não demonstrou nenhuma associação entre o uso da warfarina e elevação da pressão arterial. Pelo contrário, nos modelos de regressão múltipla, a exposição à warfarina associou-se a valores mais baixos de PAS e PP. Conclusão: O uso da warfarina em doses convencionais, por 5.5 anos, não associou-se a um aumento da pressão arterial neste estudo tranversal de pacientes com DM e hipertensão.