Risk Factor Analysis for AKI Including Laboratory Indicators: a Nationwide Multicenter Study of Hospitalized Patients

Platelet-to-Lymphocyte Ratio and In-Hospital Mortality in Patients With AKI Receiving Continuous Kidney Replacement Therapy: A Retrospective Observational Cohort Study

Rationale & Objective

The platelet-to-lymphocyte ratio (PLR) is a marker of inflammation and a predictor of mortality in a variety of diseases. However, the effectiveness of PLR as a predictor of mortality in patients with severe acute kidney injury (AKI) is uncertain. We evaluated the association between the PLR and mortality in critically ill patients with severe AKI who underwent continuous kidney replacement therapy (CKRT).

Study Design

Retrospective cohort study.

Setting & Participants

A total of 1,044 patients who underwent CKRT in a single center, from February 2017 to March 2021.

Exposures

PLR.

Outcomes

In-hospital mortality.

Analytical Approach

The study patients were classified into quintiles according to the PLR values. A Cox proportional hazards model was used to investigate the association between PLR and mortality.

Results

The PLR value was associated with in-hospital mortality in a nonlinear manner, showing a higher mortality at both ends of the PLR. The Kaplan-Meier curve revealed the highest mortality with the first and fifth quintiles, whereas the lowest mortality occurred with the third quintile. Compared with the third quintile, the first (adjusted HR, 1.94; 95% CI, 1.44-2.62; P < 0.001) and fifth (adjusted HR, 1.60; 95% CI, 1.18-2.18; P = 0.002) quintiles of the PLR group had a significantly higher in-hospital mortality rate. The first and fifth quintiles showed a consistently increased risk of 30- and 90-day mortality rates compared with those of the third quintile. In the subgroup analysis, the lower and higher PLR values were predictors of in-hospital mortality in patients with older age, of female sex, and with hypertension, diabetes, and higher Sequential Organ Failure Assessment score.

Limitations

There may be bias owing to the single-center retrospective nature of this study. We only had PLR values at the time of initiation of CKRT.

Conclusions

Both the lower and higher PLR values were independent predictors of in-hospital mortality in critically ill patients with severe AKI who underwent CKRT.

Specificity of severe AKI aetiology and care in the elderly. The IRACIBLE prospective cohort study

INTRODUCTION

Acute Kidney Injury (AKI) is increasingly common in people over 65 years of age, but its causes and management are poorly described. The purpose of this study was to describe the causes, management and prognosis of patients over 65 hospitalised for severe acute kidney injury (AKI) in all departments of a tertiary centre.

METHOD

The prospective IRACIBLE (IRA: AKI in French; CIBLE: target in French) cohort included 480 patients hospitalised at a university hospital over 18 months for severe AKI or subgroup of AKIN3 (Acute Kidney Injury Network classification) defined by an acute creatinine increase > 354 μmol/L or managed with acute renal replacement therapy (RRT). The history, aetiology of AKI, management, and prognosis were compared in three age groups: < 65, 65-75, and > 75 years.

RESULTS

The study population included 480 subjects (73% men) with a median body mass index (BMI) of 26.6 kg/m² [23.3, 30.9], 176 (37%) diabetic patients, 124 (26%) patients < 65 years, 150 (31%) 65-75 years and 206 (43%) > 75 years. Increasing age class was associated with more comorbidities, a significantly lower median estimated glomerular filtration rate (eGFR) 6 months before inclusion (82; 62; 46 ml/min/1.73 m², p < 0.05) and aetiology of AKI, which was more often obstructive (12%; 15%; 23%, p = 0.03) or part of a cardio-renal syndrome (6%; 9%; /15%, p = 0.04). Older patients were less often managed in the intensive care unit  (54%; 47%; 24%, p < 0.0001), were less frequently treated by RRT (52%; 43%; 31%, p < 0.001) and received fewer invasive treatments  (6%; 9%; 22%, p < 0.0001). Older survivors returned home less often (80%; 73%; 62%, p = 0.05) in favour of transfers to rehabilitation services (10%; 13%; 22%) with higher mortality at 3 months (35%; 32%; 50%, p < 0.0001).

CONCLUSION

Older patients hospitalised for severe AKI have a specific profile with more comorbidities, lower baseline renal function, an aetiology of AKI of mainly extra-parenchymal causes and a complex pathway of care with an overall poor prognosis.

Risk factors for and characteristics of community‐ and hospital‐acquired drug‐induced acute kidney injuries

Drugs constitute one of the leading causes of acute kidney injuries (AKIs) and can appear in community (CA‐AKI) or hospital (HA‐AKI) population. The objectives of the present study of a cohort of hospitalized patients with AKI were to describe the characteristics of drug‐induced AKIs and the patients' short‐term outcomes and assess risk factors for drug‐induced AKIs overall, CA‐AKIs, and HA‐AKIs. Based on a cohort of 1557 hospitalized patients suffering from AKIs based on PMSI extraction and chart review (IRA‐PMSI), drug‐induced AKIs were identified by applying the Naranjo adverse drug reaction (ADR) probability scale. Multivariate logistic regression was used to identify factors associated with CA‐AKIs and/or HA‐AKIs. When considering the 1557 patients who experienced an AKI, 445 (28.6%) of the injuries were drug‐induced (180 CA‐AKIs (40.4%) and 265 HA‐AKIs (59.6%)). Antibiotics, diuretics, and contrast agents were significantly more likely to be involved in HA‐AKIs, whereas antineoplastic, lipid‐lowering drugs, antidiabetics, and immunosuppressive were significantly more likely to be involved in CA‐AKIs. Female sex (odds ratio [OR] [95%CI] = 1.3 [1.04–1.67]), chronic kidney disease (CKD) (OR = 1.8 [1.40–2.67]), and a history of ADRs of any type (OR = 1.3 [1.05–1.73]) were significant risk factors for drug‐induced AKIs. CKD was a risk factor for both CA‐AKI and HA‐AKI. In view of the long‐term impact of AKI on the kidneys and the differences between our CA‐AKI and HA‐AKI subgroups, our present results are interesting for optimizing treatments, limiting the occurrence of CA‐ and HA‐AKIs and (ultimately) reducing healthcare costs.

Integrating electronic health data records to develop and validate a predictive model of hospital-acquired acute kidney injury in non-critically ill patients

Background

Models developed to predict hospital-acquired acute kidney injury (HA-AKI) in non-critically ill patients have a low sensitivity, do not include dynamic changes of risk factors and do not allow the establishment of a time relationship between exposure to risk factors and AKI. We developed and externally validated a predictive model of HA-AKI integrating electronic health databases and recording the exposure to risk factors prior to the detection of AKI.

Methods

The study set was 36 852 non-critically ill hospitalized patients admitted from January to December 2017. Using stepwise logistic analyses, including demography, chronic comorbidities and exposure to risk factors prior to AKI detection, we developed a multivariate model to predict HA-AKI. This model was then externally validated in 21 545 non-critical patients admitted to the validation centre in the period from June 2017 to December 2018.

Results

The incidence of AKI in the study set was 3.9%. Among chronic comorbidities, the highest odds ratios (ORs) were conferred by chronic kidney disease, urologic disease and liver disease. Among acute complications, the highest ORs were associated with acute respiratory failure, anaemia, systemic inflammatory response syndrome, circulatory shock and major surgery. The model showed an area under the curve (AUC) of 0.907 [95% confidence interval (CI) 0.902–0.908), a sensitivity of 82.7 (95% CI 80.7–84.6) and a specificity of 84.2 (95% CI 83.9–84.6) to predict HA-AKI, with an adequate goodness-of-fit for all risk categories (χ² = 6.02, P = 0.64). In the validation set, the prevalence of AKI was 3.2%. The model showed an AUC of 0.905 (95% CI 0.904–0.910), a sensitivity of 81.2 (95% CI 79.2–83.1) and a specificity of 82.5 (95% CI 82.2–83) to predict HA-AKI and had an adequate goodness-of-fit for all risk categories (χ² = 4.2, P = 0.83). An online tool (predaki.amalfianalytics.com) is available to calculate the risk of AKI in other hospital environments.

Conclusions

By using electronic health data records, our study provides a model that can be used in clinical practice to obtain an accurate dynamic and updated assessment of the individual risk of HA-AKI during the hospital admission period in non-critically ill patients.

Association of Acute Kidney Injury with the Risk of Dementia: A Meta-Analysis

Acute kidney injury (AKI) is associated with several adverse outcomes, including new or progressive chronic kidney disease, end-stage kidney disease, and mortality. Epidemiological studies have reported an association between AKI and dementia as a long-term adverse outcome. This meta-analysis was aimed to understand the association between AKI and dementia risk. A literature search was performed in MEDLINE and Embase databases, from inception to July 2021, to identify epidemiological studies reporting the association between AKI and dementia risk. Title and abstract followed by the full-text of retrieved articles were screened, data were extracted, and quality was assessed, using the Newcastle-Ottawa scale by two investigators independently. The primary outcome was to compute the pooled risk of dementia in AKI patients. Subgroup analysis was also performed based on age and co-morbidities. Certainty of evidence was assessed using the GRADE approach. Statistical analysis was performed using Review Manager 5.4 software. Four studies (cohort (n = 3) and case-control (n = 1)) with a total of 429,211 patients, of which 211,749 had AKI, were identified. The mean age of the patients and the follow-up period were 64.15 ± 16.09 years and 8.9 years, respectively. Included studies were of moderate to high quality. The pooled estimate revealed a significantly higher risk of dementia in AKI patients with an overall relative risk/risk ratio (RR) of 1.92 (95% CI: 1.52-2.43), p ≤ 0.00001. Dementia risk increases by 10% with one year increase in age with an RR of 1.10 (95% CI: 1.09-1.11), p < 0.00001. Subgroup analysis based on stroke as a co-morbid condition also revealed significantly higher dementia risk in AKI patients (RR 2.30 (95% CI: 1.62-3.28), p = 0.009). All-cause mortality risk was also significantly higher in AKI patients with dementia with a pooled RR of 2.11 (95% CI: 1.20-3.70), p = 0.009. The strength of the evidence was of very low certainty as per the GRADE assessment. Patients with AKI have a higher risk of dementia. Further large epidemiological studies are needed to confirm the mechanistic association.

Association between Procalcitonin and Acute Kidney Injury in Patients with Bacterial Septic Shock

OBJECTIVE

The objective of this study was to assess the relationship between serum procalcitonin (PCT) and acute kidney injury (AKI) induced by bacterial septic shock.

METHODS

A retrospective study was designed which included patients who were admitted to the ICU from January 2015 to October 2018. Multiple logistic regression and receiver operating characteristic (ROC) as well as smooth curve fitting analysis were used to assess the relationship between the PCT level and AKI.

RESULTS

Of the 1,631 patients screened, 157 patients were included in the primary analysis in which 84 (53.5%) patients were with AKI. Multiple logistic regression results showed that PCT (odds ratio [OR] = 1.017, 95% confidence interval [CI] 1.009-1.025, p < 0.001) was associated with AKI induced by septic shock. The ROC analysis showed that the cutoff point for PCT to predict AKI development was 14 ng/mL, with a sensitivity of 63% and specificity 67%. Specifically, in multivariate piecewise linear regression, the occurrence of AKI decreased with the elevation of PCT when PCT was between 25 ng/mL and 120 ng/mL (OR 0.963, 95% CI 0.929-0.999; p = 0.042). The AKI increased with the elevation of PCT when PCT was either <25 ng/mL (OR 1.077, 95% CI 1.022-1.136; p = 0.006) or >120 ng/mL (OR 1.042, 95% CI 1.009-1.076; p = 0.013). Moreover, the PCT level was significantly higher in the AKI group only in female patients aged ≤75 years (p = 0.001).

CONCLUSIONS

Our data revealed a nonlinear relationship between PCT and AKI in septic shock patients, and PCT could be used as a potential biomarker of AKI in female patients younger than 75 years with bacterial septic shock.

Clinical Characteristics and Risk Factors for Acute Kidney Injury in COVID-19

Objective:

The objective of the study is to describe the clinical characteristics, risk factors, and prognosis for acute kidney injury (AKI) among patients with coronavirus disease (COVID-19).

Methods:

Retrospective study of 456 consecutive patients with confirmed COVID-19 infection at the whole hospital from January 1 to March 1, 2020 was enrolled. Demographic, clinical characteristics, the risk factors, and prognosis were collected and analyzed.

Results:

Of 456 patients with COVID-19, 38 patients developed AKI. Patients with AKI were older and predominantly male sex and were more likely to have comorbidities such as hypertension, cardiovascular, and cerebrovascular diseases. Among patients with AKI, the white blood cell count, neutrophil count, neutrophil-to-lymphocyte ratio, alanine aminotransferase, and C-reaction protein were increased, and lymphocyte and platelet count were decreased. Multivariate analysis showed that age, hypertension, and lymphocyte count were independent risk factors for AKI. The overall mortality rate of 456 patients was 9.9%, and the mortality rate of patients with AKI was 23.7%. In particular, increasing AKI severity was associated with increased risk.

Conclusions:

The risk of AKI was high in patients with COVID-19. Older age, hypertension, and lower lymphocyte count were independent risk factors for AKI. COVID-19-associated AKI was associated with higher risk of death in patients with COVID-19.

Mechanisms of Renal-Splenic Axis Involvement in Acute Kidney Injury Mediated by the α7nAChR-NF-κB Signaling Pathway

This study aimed to investigate the effect of splenectomy on dexmedetomidine-activated cholinergic anti-inflammatory pathway-mediated alleviation of LPS-induced AKI. A mouse model of septic kidney injury was established in C57BL/6 mice. A total of 30 C57BL/6 mice were randomly divided into the control group, LPS group, dexmedetomidine + LPS group, splenectomy group, splenectomy + LPS group, and splenectomy + dexmedetomidine + LPS group. The pathological effects in kidney tissues in each group were analyzed by HE staining. Apoptosis in each group was examined by the TUNEL method. Cr and Cys-C levels in each group were measured by ELISA. The expression levels of IL-6, NF-κB p65, Caspase-3, the antiapoptotic protein Bcl-2, the proapoptotic protein Bax, and α7nAChR in each group were measured by qRT-PCR and Western blotting. Dexmedetomidine alone reduced apoptosis in kidney tissue; however, apoptosis was increased after splenectomy in mice treated with dexmedetomidine. Splenectomy reduced the production of proinflammatory cytokines in circulation and had a protective effect on the kidney. Splenectomy inhibited dexmedetomidine-mediated activation of the α7nAChR pathway. Dexmedetomidine effectively alleviated LPS-induced kidney injury, and splenectomy inhibited the anti-inflammatory, antiapoptotic, and renoprotective effects of dexmedetomidine. The kidney-spleen axis is mediated by the α7nAChR-NF-κB signaling pathway and is involved in the development of AKI.

Clinical characteristics of acute glomerulonephritis with presentation of nephrotic syndrome at onset in children

BACKGROUND

Acute glomerulonephritis (AGN) is a common disease in children, which places a huge burden on developing countries. The prognosis of it may not always be good. However, the clinical characteristics of AGN with nephrotic syndrome (NS) at onset have not been fully clarified.

METHODS

One hundred and thirteen cases were analyzed retrospectively. Clinical data, pathological results and prognosis between AGN with NS (AGN-NS) and AGN without NS (AGN-no-NS) were compared.

RESULTS

Twenty (17.7%) of 113 patients were AGN-NS. The patients with AGN-NS were more likely to have hypertension (55.0% vs. 25.8%) and acute kidney injury (AKI) (50.0% vs. 17.2%). AKI was significantly related to the manifestation of AGN-NS in children (OR = 3.812, P = 0.040). Compared with the AGN-no-NS, the immunosuppressive treatments were more common in AGN-NS. A more severe pathological grade was significantly related to lower C3 fraction, estimated glomerular filtration rate (eGFR), and AKI, but not to the performance of AGN-NS. There was no difference in prognosis between the two groups.

CONCLUSIONS

AKI was significantly associated with AGN-NS. The prognosis of AGN-NS and AGN-no-NS in our study was almost good. Given the fact that AGN-NS patients are more likely to use immunosuppressive therapy, the long-term outcome of AGN-NS warrants further research.

AKI!Now Initiative: Recommendations for Awareness, Recognition, and Management of AKI

The American Society of Nephrology has established a new initiative, AKI!Now, with the goal of promoting excellence in the prevention and treatment of AKI by building a foundational program that transforms education and delivery of AKI care, aiming to reduce morbidity and associated mortality and to improve long-term outcomes. In this article, we describe our current efforts to improve early recognition and management involving inclusive interdisciplinary collaboration between providers, patients, and their families; discuss the ongoing need to change some of our current AKI paradigms and diagnostic methods; and provide specific recommendations to improve AKI recognition and care. In the hospital and the community, AKI is a common and increasingly frequent condition that generates risks of adverse events and high costs. Unfortunately, patients with AKI may frequently have received less than optimal quality of care. New classifications have facilitated understanding of AKI incidence and its impact on outcomes, but they are not always well aligned with AKI pathophysiology. Despite ongoing research efforts, treatments to promote or hasten kidney recovery remain ineffective. To avoid progression, the current approach to AKI emphasizes the promotion of early recognition and timely response. However, a lack of awareness of the importance of early recognition and treatment among health care team members and the heterogeneity of approaches within the health care teams assessing the patient remains a major challenge. Early identification is further complicated by differences in settings where AKI occurs (the community or the hospital), and by differences in patient populations and cultures between the intensive care unit and ward environments. To address these obstacles, we discuss the need to improve education at all levels of care and to generate specific guidance on AKI evaluation and management, including the development of a widely applicable education and an AKI management toolkit, engaging hospital administrators to incorporate AKI as a quality initiative, and raising awareness of AKI as a complication of other disease processes.

Female sex reduces the risk of hospital-associated acute kidney injury: a meta-analysis

Background

Female sex has been included as a risk factor in models developed to predict the development of AKI. In addition, the commentary to the Kidney Disease Improving Global Outcomes Clinical Practice Guideline for AKI concludes that female sex is a risk factor for hospital-acquired AKI. In contrast, a protective effect of female sex has been demonstrated in animal models of ischemic AKI.

Methods

To further explore this issue, we performed a meta-analysis of AKI studies published between January, 1978 and April, 2018 and identified 83 studies reporting sex-stratified data on the incidence of hospital-associated AKI among nearly 240,000,000 patients.

Results

Twenty-eight studies (6,758,124 patients) utilized multivariate analysis to assess risk factors for hospital-associated AKI and provided sex-stratified ORs. Meta-analysis of this cohort showed that the risk of developing hospital-associated AKI was significantly greater in men than in women (OR 1.23 (1.11,1.36). Since AKI is not a single disease but instead represents a heterogeneous group of disorders characterized by an acute reduction in renal function, we performed subgroup meta-analyses. The association of male sex with AKI was strongest among studies of patients who underwent non-cardiac surgery. Male sex was also associated with AKI in studies which included unselected hospitalized patients and in studies of critically ill patients who received care in an intensive care unit. In contrast, cardiac surgery-associated AKI and radiocontrast-induced AKI showed no sexual dimorphism.

Conclusions

Our meta-analysis contradicts the established belief that female sex confers a greater risk of AKI and instead suggests a protective role.

Combination of Mean Platelet Volume/Platelet Count Ratio and the APACHE II Score Better Predicts the Short-Term Outcome in Patients with Acute Kidney Injury Receiving Continuous Renal Replacement Therapy

BACKGROUND/AIMS

Both the Acute physiology and Chronic Health Evaluation (APACHE II) score and mean platelet volume/platelet count Ratio (MPR) can independently predict adverse outcomes in critically ill patients. This study was aimed to investigate whether the combination of them could have a better performance in predicting prognosis of patients with acute kidney injury (AKI) who received continuous renal replacement therapy (CRRT).

METHODS

Two hundred twenty-three patients with AKI who underwent CRRT between January 2009 and December 2014 in a Chinese university hospital were enrolled. They were divided into survivals group and non-survivals group based on the situation at discharge. Receiver Operating Characteristic (ROC) curve was used for MPR and APACHE II score, and to determine the optimal cut-off value of MPR for in-hospital mortality. Factors associated with mortality were identified by univariate and multivariate logistic regression analysis.

RESULTS

The mean age of the patients was 61.4 years, and the overall in-hospital mortality was 48.4%. Acute cardiorenal syndrome (ACRS) was the most common cause of AKI. The optimal cut-off value of MPR for mortality was 0.099 with an area under the ROC curve (AUC) of 0.636. The AUC increased to 0.851 with the addition of the APACHE II score. The mortality of patients with of MPR > 0.099 was 56.4%, which was significantly higher than that of the control group with of ≤ 0.099 (39.6%, P= 0.012). Logistic regression analysis showed that average number of organ failure (OR = 2.372), APACHE II score (OR = 1.187), age (OR = 1.028) and vasopressors administration (OR = 38.130) were significantly associated with poor prognosis.

CONCLUSION

Severity of illness was significantly associated with prognosis of patients with AKI. The combination of MPR and APACHE II score may be helpful in predicting the short-term outcome of AKI.