Risk for Chronic Kidney Disease Progression After Acute Kidney Injury: Findings From the Chronic Renal Insufficiency Cohort Study

Acute Kidney Injury and Its Association With Dementia and Specific Dementia Types: Findings From a Population-Based Study in Sweden

BACKGROUND AND OBJECTIVES

Preclinical studies suggest that acute kidney injury (AKI) results in biochemical and pathologic changes in the brain. We aimed to explore the association between experiencing AKI and subsequent risks of developing dementia.

METHODS

We conducted a study involving individuals aged 65 years and older in Stockholm from 2006 to 2019, who were free from dementia diagnosis and had data on kidney function. The exposure was an episode of AKI (time varying), ascertained by issued clinical diagnoses and transient creatinine elevations according to Kidney Disease Improving Global Outcomes criteria. The outcome was all-cause dementia and specific types of dementia, ascertained by clinically confirmed cases in the Swedish registry of cognitive/dementia disorders, the presence of 2 issued dementia diagnoses in outpatient care, or initiation of specific antidementia medications. We investigated associations with dementia through Cox proportional hazard regression by AKI, severity levels of AKI, AKI recurrence, and setting (community-acquired or hospital-acquired AKI).

RESULTS

We included 305,122 individuals with a median age of 75 ± 8 years (56.6% women). During a median follow-up of 12.3 (interquartile range 8.7-13.3) years, there were 79,888 individuals (26%) suffering from at least 1 episode of AKI and 47,938 incident cases (16%) of dementia. The rate of dementia cases was 37.0 per 1,000 person-years (95% CI 36.2-37.8) after developing AKI, which was approximately 2 times higher than the rate observed during the periods before AKI (17.3, 95% CI 17.2-17.5). After multivariable adjustment, developing AKI was associated with a 49% higher rate of subsequent dementia (adjusted hazard ratio hazard ratio [HR] 1.49, 95% CI 1.45-1.53). This pattern was consistent across dementia types, with HRs of 1.88 (95% CI 1.53-2.32), 1.47 (1.38-1.56), and 1.31 (1.25-1.38) for dementia with Lewy bodies and Parkinson disease with dementia, vascular dementia, and Alzheimer dementia, respectively. Risk associations were stronger in magnitude across more severe AKIs and in hospital-acquired vs community-acquired AKI.

DISCUSSION

Individuals who experienced an AKI were at increased risk of receiving a diagnosis of dementia.

Dynamically visualizing profibrotic maladaptive repair after acute kidney injury by fibroblast activation protein imaging

A major challenge in prevention and early treatment of organ fibrosis is the lack of valuable tools to assess the evolving profibrotic maladaptive repair after injury in vivo in a non-invasive way. Here, using acute kidney injury (AKI) as an example, we tested the utility of fibroblast activation protein (FAP) imaging for dynamic assessment of maladaptive repair after injury. The temporospatial pattern of kidney FAP expression after injury was first characterized. Single-cell RNA sequencing and immunostaining analysis of patient biopsies were combined to show that FAP was specifically upregulated in kidney fibroblasts after AKI and was associated with fibroblast activation and chronic kidney disease (CKD) progression. This was corroborated in AKI mouse models, where a sustained and exaggerated kidney FAP upregulation was coupled to persistent fibroblast activation and a fibrotic outcome, linking kidney FAP level to post-insult maladaptive repair. Furthermore, using positron emission tomography (PET)/CT scanning with FAP-inhibitor tracers ([18F]FAPI-42, [18F]FAPT) targeting FAP, demonstrated the feasibility of non-invasively tracking of maladaptive repair evolution toward kidney fibrosis. Importantly, a sustained increase in kidney [18F]FAPT (less hepatobiliary metabolized than [18F]FAPI-42) uptake reflected persistent kidney upregulation of FAP and characterized maladaptive repair after AKI. Kidney [18F]FAPT uptake at hour 2-day 7 correlated with kidney fibrosis 14 days after AKI. Similar changes in [18F]FAPI-42 PET/CT imaging were observed in patients with AKI and CKD progression. Thus, persistent kidney FAP upregulation after AKI was associated with maladaptive repair and a fibrotic outcome. Hence, FAP-specific PET/CT imaging enables dynamic visualization of maladaptive repair after AKI and prediction of kidney fibrosis within a clinically actionable window.

Clinical Characteristics and the Prognostic Impact of Acute Kidney Injury in Critically Ill Patients with Invasive Pulmonary Aspergillosis in the Intensive Care Unit: A Retrospective, Single-Center Study

Introduction

The incidence and impact of acute kidney injury (AKI) in patients with invasive pulmonary aspergillosis (IPA) admitted to the intensive care unit (ICU) are unknown.

Methods

This retrospective study included 140 patients who were diagnosed with IPA and admitted to the medical ICU of China-Japan Friendship Hospital in Beijing, China. AKI was defined according to the Kidney Disease: Improving Global Outcomes guidelines. Data on demographic characteristics, comorbidities, laboratory tests, treatments, and prognosis at ICU admission were collected.

Results

The rate of AKI was 71.4% (n = 100), and approximately 30% of the patients had preadmission acute kidney dysfunction. Of the 100 patients with AKI, 19, 8, and 73 patients had stage I, II, and III AKI, respectively, and 64 (87.6%) patients required continuous renal replacement therapy. Overall ICU mortality rate was 52.1%. Irreversible AKI was a strong independent risk factor for ICU mortality (odds ratio 13.36, 95% confidence interval 4.52-39.48, p < 0.001), followed by chronic lung disease, use of intermittent positive-pressure ventilation, and long-term corticosteroid treatment within 1 year prior to ICU admission. Higher cardiac troponin I levels at admission and worse volume control during the first 7 days of ICU stay were potential predictive factors of irreversible kidney dysfunction. Patients with irreversible AKI and those who died during the ICU stay had greater volume overload during the first 14 days of ICU stay. Patients who survived received earlier renal replacement therapy support after ICU admission compared to those who died (median, 2 vs. 5 days; p = 0.026).

Conclusion

Compared to the patients with IPA in the absence of AKI, those with AKI presented with more volume overload, worse disease burden, and required stronger respiratory support, while experiencing worse prognosis. Irreversible AKI was a strong predictor of mortality in patients with critical IPA. Better volume control and earlier CRRT initiation should be considered key points in AKI management and prognostic improvement.

Therapeutic role of extracellular vesicles from human umbilical cord mesenchymal stem cells and their wide therapeutic implications in inflammatory bowel disease and other inflammatory disorder

The chronic immune-mediated inflammatory condition known as inflammatory bowel disease (IBD) significantly affects the gastrointestinal system. While the precise etiology of IBD remains elusive, extensive research suggests that a range of pathophysiological pathways and immunopathological mechanisms may significantly contribute as potential factors. Mesenchymal stem cells (MSCs) have shown significant potential in the development of novel therapeutic approaches for various medical conditions. However, some MSCs have been found to exhibit tumorigenic characteristics, which limit their potential for medical treatments. The extracellular vesicles (EVs), paracrine factors play a crucial role in the therapeutic benefits conferred by MSCs. The EVs consist of proteins, microRNAs, and lipids, and are instrumental in facilitating intercellular communication. Due to the ease of maintenance, and decreased immunogenicity, tumorigenicity the EVs have become a new and exciting option for whole cell treatment. This review comprehensively assesses recent preclinical research on human umbilical cord mesenchymal stem cell (hUC-MSC)-derived EVs as a potential IBD therapy. It comprehensively addresses key aspects of various conditions, including diabetes, cancer, dermal injuries, neurological disorders, cardiovascular issues, liver and kidney diseases, and bone-related afflictions.

An overview of circulating and urinary biomarkers capable of predicting the transition of acute kidney injury to chronic kidney disease

INTRODUCTION

Acute kidney injury (AKI) defined by a substantial decrease in kidney function within hours to days and is often irreversible with higher risk to chronic kidney disease (CKD) transition.

AREAS COVERED

The authors discuss the diagnostic and predictive utilities of serum and urinary biomarkers on AKI and on the risk of AKI-to-CKD progression. The authors focus on the relevant literature covering evidence of circulating and urinary biomarkers' capability to predict the transition of AKI to CKD.

EXPERT OPINION

Based on the different modalities of serum and urinary biomarkers, multiple biomarker panel seems to be potentially useful to distinguish between various types of AKI, to detect the severity and the risk of AKI progression, to predict the clinical outcome and evaluate response to the therapy. Serum/urinary neutrophil gelatinase-associated lipocalin (NGAL), serum/urinary uromodulin, serum extracellular high mobility group box-1 (HMGB-1), serum cystatin C and urinary liver-type fatty acid-binding protein (L-FABP) were the most effective in the prediction of AKI-to-CKD transition regardless of etiology and the presence of critical state in patients. The current clinical evidence on the risk assessments of AKI progression is mainly based on the utility of combination of functional, injury and stress biomarkers, mainly NGAL, L-FABP, HMGB-1 and cystatin C.

Within and post-trial effects of an intensive lifestyle intervention on kidney disease in adults with overweight or obesity and type 2 diabetes mellitus: a secondary analysis of the Look AHEAD clinical trial

INTRODUCTION

The Look AHEAD randomized clinical trial reported that an 8-year intensive lifestyle intervention (ILI) compared with diabetes support and education (DSE) in adults aged 45-76 years with type 2 diabetes and overweight/obesity delayed kidney disease progression. Here, we report long-term post-intervention follow-up for the trial's secondary outcome of kidney disease.

RESEARCH DESIGN AND METHODS

We examined effects of ILI (n=2570) versus DSE (n=2575) on decline in estimated glomerular filtration rate (eGFR) to <45 mL/min/1.73 m2 or need for kidney replacement therapy (KRT: dialysis or kidney transplant) during intervention and post-intervention follow-up (median 15.6 years overall).

RESULTS

Incidence of eGFR <45 mL/min/1.73 m2 was lower in ILI during the intervention (HR=0.80, 95% CI=0.66 to 0.98) but not post-intervention (HR=1.03, 0.86 to 1.23) or overall (HR=0.92, 0.80 to 1.04). There were no significant treatment group differences in KRT. In prespecified subgroup analyses, age×treatment interactions were significant over total follow-up: p=0.001 for eGFR <45 mL/min/1.73 m2 and p=0.01 for KRT. The 2205 participants aged >60 years at baseline had benefit in both kidney outcomes during intervention and overall (HR=0.75, 0.62 to 0.90 for eGFR <45 mL/min/1.73 m2; HR=0.62, 0.43 to 0.91 for KRT). The absolute treatment effects were greater post-intervention: ILI reduced the rate of eGFR <45 mL/min/1.73 m2 by 0.46 and 0.76 cases/100 person-years during and post-intervention, respectively; and reduced KRT by 0.15 and 0.21 cases/100 person-years. The younger participants experienced no such post-intervention benefits.

CONCLUSIONS

ILI reduced kidney disease progression during and following the active intervention in persons aged ≥60 years. ILI should be considered for reducing kidney disease incidence in older persons with type 2 diabetes.

Acute kidney disease beyond day 7 after major surgery: a secondary analysis of the EPIS-AKI trial

PURPOSE

Acute kidney disease (AKD) is a significant health care burden worldwide. However, little is known about this complication after major surgery.

METHODS

We conducted an international prospective, observational, multi-center study among patients undergoing major surgery. The primary study endpoint was the incidence of AKD (defined as new onset of estimated glomerular filtration rate (eCFR) < 60 ml/min/1.73 m2 present on day 7 or later) among survivors. Secondary endpoints included the relationship between early postoperative acute kidney injury (AKI) (within 72 h after major surgery) and subsequent AKD, the identification of risk factors for AKD, and the rate of chronic kidney disease (CKD) progression in patients with pre-existing CKD.

RESULTS

We studied 9510 patients without pre-existing CKD. Of these, 940 (9.9%) developed AKD after 7 days of whom 34.1% experiencing an episode of early postoperative-AKI. Rates of AKD after 7 days significantly increased with the severity (19.1% Kidney Disease Improving Global Outcomes [KDIGO] 1, 24.5% KDIGO2, 34.3% KDIGO3; P < 0.001) and duration (15.5% transient vs 38.3% persistent AKI; P < 0.001) of early postoperative-AKI. Independent risk factors for AKD included early postoperative-AKI, exposure to perioperative nephrotoxic agents, and postoperative pneumonia. Early postoperative-AKI carried an independent odds ratio for AKD of 2.64 (95% confidence interval [CI] 2.21-3.15). Of 663 patients with pre-existing CKD, 42 (6.3%) had worsening CKD at day 90. In patients with CKD and an episode of early AKI, CKD progression occurred in 11.6%.

CONCLUSION

One in ten major surgery patients developed AKD beyond 7 days after surgery, in most cases without an episode of early postoperative-AKI. However, early postoperative-AKI severity and duration were associated with an increased rate of AKD and early postoperative-AKI was strongly associated with AKD independent of all other potential risk factors.

Clinicopathological Characteristics and Prognosis of Lupus Nephritis Patients with Acute Kidney Injury

INTRODUCTION

Acute kidney injury (AKI) is common in lupus nephritis (LN) and a risk factor for chronic kidney failure. Here, we aimed to assess the characteristics and prognosis of LN patients with AKI.

METHODS

AKI and AKI severity stages in LN patients were defined by the Kidney Disease Improving Global Outcomes (KDIGO) classification. Long-term renal outcomes and patient mortality between different stages of AKI were compared by Cox regression analysis.

RESULTS

Of 1272 LN patients, 225 (17.69%) had AKI and 72 (5.66%) were AKI stage 3. Compared with the non-AKI group, the proportion of male patients was significantly higher in the AKI group (p = 0.002). In addition, there were markedly higher proportions of hematologic system damage, more severe renal manifestations, and higher Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores in the AKI group than in the non-AKI group. The active and chronic lesions in renal biopsy were significantly higher in LN patients with AKI than those without AKI. During a median follow-up of 53 months, Kaplan-Meier curve showed that LN patients with AKI stage 3 had significantly poorer long-term renal outcomes (p = 0.002) and patient survival (p < 0.001) than those without AKI. Furthermore, AKI stage 3, but not stage 1 or 2 was significantly associated with adverse renal outcomes (hazard ratio [HR] = 2.52, 95% confidence interval [CI] 1.01-6.28, p = 0.048) and all-cause mortality (HR = 2.80, 95% CI: 1.18-6.61, p = 0.019) in LN patients. In patients with AKI, increased baseline serum creatinine and severe glomerular sclerosis were independent risk factors for worse renal outcomes, while higher blood pressure, increased baseline serum creatinine, and anti-Sjogren's syndrome A positivity could indicate poor survival.

DISCUSSION

LN patients with AKI stage 3, but not stages 1 and 2, have poorer long-term renal outcomes and patient survival. Our study demonstrates the importance of early identification and management of AKI in LN patients.