Post-contrast acute kidney injury in a hospitalized population: short-, mid-, and long-term outcome and risk factors for adverse events

Development and validation of a prediction model for people with mild chronic kidney disease in Japanese individuals

BACKGROUND

Chronic kidney disease (CKD) poses significant health risks due to its asymptomatic nature in early stages and its association with increased cardiovascular and kidney events. Early detection and management are critical for improving outcomes.

OBJECTIVE

This study aimed to develop and validate a prediction model for hospitalization for ischemic heart disease (IHD) or cerebrovascular disease (CVD) and major kidney events in Japanese individuals with mild CKD using readily available health check and prescription data.

METHODS

A retrospective cohort study was conducted using data from approximately 850,000 individuals in the PREVENT Inc. database, collected between April 2013 and April 2023. Cox proportional hazard regression models were utilized to derive and validate risk scores for hospitalization for IHD/CVD and major kidney events, incorporating traditional risk factors and CKD-specific variables. Model performance was assessed using the concordance index (c-index) and 5-fold cross-validation.

RESULTS

A total of 40,351 individuals were included. Key predictors included age, sex, diabetes, hypertension, and lipid levels for hospitalization for IHD/CVD and major kidney events. Age significantly increased the risk score for both hospitalization for IHD/CVD and major kidney events. The baseline 5-year survival rates are 0.99 for hospitalization for IHD/CVD and major kidney events are 0.99. The developed risk models demonstrated predictive ability, with mean c-indexes of 0.75 for hospitalization for IHD/CVD and 0.69 for major kidney events.

CONCLUSIONS

This prediction model offers a practical tool for early identification of Japanese individuals with mild CKD at risk for hospitalization for IHD/CVD and major kidney events, facilitating timely interventions to improve patient outcomes and reduce healthcare costs. The models stratified patients into risk categories, enabling identification of those at higher risk for adverse events. Further clinical validation is required.

Heterogeneity in the definition of major adverse kidney events: a scoping review

Acute kidney injury (AKI) is associated with persistent renal dysfunction, the receipt of dialysis, dialysis dependence, and mortality. Accordingly, the concept of major adverse kidney events (MAKE) has been adopted as an endpoint for assessing the impact of AKI. However, applied criteria or observation periods for operationalizing MAKE appear to vary across studies. To evaluate this heterogeneity for MAKE evaluation, we performed a systematic scoping review of studies that employed MAKE as an AKI endpoint. Four major academic databases were searched, and we identified 122 studies with increasing numbers over time. We found marked heterogeneity in applied criteria and observation periods for MAKE across these studies, with some even lacking a description of criteria. Moreover, 13 different observation periods were employed, with 30 days and 90 days as the most common. Persistent renal dysfunction was evaluated by estimated glomerular filtration rate (34%) or serum creatinine concentration (48%); however, 37 different definitions for this component were employed in terms of parameters, cut-off criteria, and assessment periods. The definition for the dialysis component also showed significant heterogeneity regarding assessment periods and duration of dialysis requirement (chronic vs temporary). Finally, MAKE rates could vary by 7% [interquartile range: 1.7-16.7%] with different observation periods or by 36.4% with different dialysis component definitions. Our findings revealed marked heterogeneity in MAKE definitions, particularly regarding component assessment and observation periods. Dedicated discussion is needed to establish uniform and acceptable standards to operationalize MAKE in terms of selection and applied criteria of components, observation period, and reporting criteria for future trials on AKI and related conditions.

Effects of Low-Osmolar Contrast Media on Long-Term Renal Impairment After Coronary Angiography: Iohexol Versus Iopromide

To investigate the long-term effects of 2 commonly used low-osmolar contrast media, iohexol and iopromide, on renal function and survival in patients who underwent coronary angiography. A total of 14,141 cardiology patients from 2006 to 2013 were recruited, of whom 1,793 patients (679 patients on iohexol and 1,114 on iopromide) were evaluated for long-term renal impairment and 5,410 patients (1,679 patients on iohexol and 3,731 on iopromide) were admitted for survival analyses spanning as long as 15 years. Univariate and multivariate logistic regression were used to explore the risk factors for long-term renal impairment. Cox proportional hazard regression was used to investigate the risk factors affecting survival. Propensity score matching and inverse probability of treatment weighting were applied to balance the baseline clinical characteristics. Patients receiving iohexol demonstrated a greater occurrence of renal impairment compared with those who received iopromide. Such difference remained consistent both before and after propensity score matching or inverse probability of treatment weighting, with a statistical significance of p <0.05. Among clinical variables, receiving contrast-enhanced contrast tomography/magnetic resonance imaging during follow-up, antihypertensive medication usage, presence of proteinuria, and anemia were identified as risk factors for long-term renal impairment (p = 0.041, 0.049, 0.006, and 0.029, respectively). During survival analyses, the difference was insignificant after propensity score matching and inverse probability of treatment weighting. In conclusion, administration of iohexol was more likely to induce long-term renal impairment than iopromide, particularly among patients diagnosed with anemia and proteinuria and those taking antihypertensive medication and with additional contrast exposure. The all-cause mortality, however, showed no significant difference between iohexol and iopromide administration.

Apelin-13 alleviates contrast-induced acute kidney injury by inhibiting endoplasmic reticulum stress

Contrast-induced acute kidney injury (CI-AKI) is a severe complication associated with significant morbidity and mortality, and effective therapeutic strategies are still lacking. Apelin is an endogenous physiological regulator with antioxidative, anti-inflammatory and antiapoptotic properties. However, the role of apelin-13 in CI-AKI remains unclear. In our study, we found that the protein expression levels of apelin were significantly downregulated in rat kidney tissues and HK-2 cells during contrast media treatment. Moreover, we explored the protective effect of apelin-13 on renal tubule damage using in vitro and in vivo models of CI-AKI. Exogenous apelin-13 ameliorated endoplasmic reticulum stress, reactive oxygen species and apoptosis protein expression in contrast media-treated cells and rat kidney tissues. Mechanistically, the downregulation of endoplasmic reticulum stress contributed critically to the antiapoptotic effect of apelin-13. Collectively, our findings reveal the inherent mechanisms by which apelin-13 regulates CI-AKI and provide a prospective target for the prevention of CI-AKI.

Shrunken Pore Syndrome: A New and More Powerful Phenotype of Renal Dysfunction Than Chronic Kidney Disease for Predicting Contrast-Associated Acute Kidney Injury

Background Shrunken pore syndrome (SPS) as a novel phenotype of renal dysfunction is characterized by a difference in renal filtration between cystatin C and creatinine. The manifestation of SPS was defined as a cystatin C-based estimated glomerular filtration rate (eGFR) <60% of the creatinine-based eGFR. SPS has been shown to be associated with the progression and adverse prognosis of various cardiovascular and renal diseases. However, the predictive value of SPS for contrast-associated acute kidney injury (CA-AKI) and long-term outcomes in patients undergoing percutaneous coronary intervention remains unclear. Methods and Results We retrospectively observed 5050 consenting patients from January 2012 to December 2018. Serum cystatin C and creatinine were measured and applied to corresponding 2012 and 2021 Chronic Kidney Disease Epidemiology Collaboration equations, respectively, to calculate the eGFR. Chronic kidney disease (CKD) was defined as a creatinine-based eGFR <60 mL/min per 1.73 m² without dialysis. CA-AKI was defined as an increase in serum creatinine ≥50% or 0.3 mg/dL within 48 hours after contrast medium exposure. Overall, 649 (12.85%) patients had SPS, and 324 (6.42%) patients developed CA-AKI. Multivariate logistic regression analysis indicated that SPS was significantly associated with CA-AKI after adjusting for potential confounding factors (odds ratio [OR], 4.17 [95% CI, 3.17-5.46]; P<0.001). Receiver operating characteristic analysis indicated that the cystatin C-based eGFR:creatinine-based eGFR ratio had a better performance and stronger predictive power for CA-AKI than creatinine-based eGFR (area under the curve: 0.707 versus 0.562; P<0.001). Multivariate logistic analysis revealed that compared with those without CKD and SPS simultaneously, patients with CKD and non-SPS (OR, 1.70 [95% CI, 1.11-2.55]; P=0.012), non-CKD and SPS (OR, 4.02 [95% CI, 2.98-5.39]; P<0.001), and CKD and SPS (OR, 8.62 [95% CI, 4.67-15.7]; P<0.001) had an increased risk of CA-AKI. Patients with both SPS and CKD presented the highest risk of long-term mortality compared with those without both (hazard ratio, 2.30 [95% CI, 1.38-3.86]; P=0.002). Conclusions SPS is a new and more powerful phenotype of renal dysfunction for predicting CA-AKI than CKD and will bring new insights for an accurate clinical assessment of the risk of CA-AKI.

Predictive Value of Hyperuricemia in Cardiac Patients with Post-Contrast Acute Kidney Injury (PC-AKI) and Different Basic Renal Functions: A Meta-Analysis

Background

Uric acid level has shown a certain relationship with the incidence of post-contrast acute kidney injury (PC-AKI), whereas it remains controversial whether hyperuricemia can function as a predictor of PCAKI in patients with different basic creatinine serum level. The present meta-analysis aimed to investigate whether hyperuricemia is an independent risk factor for PC-AKI and to explore the relationship between hyperuricemia and basic renal function.

Methods

Relevant studies were retrieved via searching in PubMed, Embase, Cochrane Library, and WAN FANG electronic databases from inception to Jan 2022. Only studies published in English and Chinese languages were selected.

Results

Overall, 11892 patients from 15 studies were included. The results of the pooled analysis revealed that the incidence of PC-AKI was significantly higher in the hyperuricemia group than that in the normouricemic group (20.62% vs. 13.05%). Hyperuricemia was associated with an increased risk of the incidence of PC-AKI (odds ratio (OR): 2.48 [95% confidence interval (CI): 1.77-3.46%]). The pooled ORs for mortality and incidence of undergoing renal replacement therapy were 2.33 (95% CI:1.81-3.00) and 8.69 (95% CI:3.22-23.44%), respectively. Comparatively, the pre-existing renal dysfunction subgroup had a lower relative risk in the hyperuricemia population.

Conclusion

Hyperuricemia was found to be significantly associated with the incidence of PC-AKI. The effect of serum uric acid level on the incidence of PC-AKI was higher in patients with normal renal function, which could lay a foundation for the establishment of individualized schemes to prevent PC-AKI by urate-lowering therapy.

Drug-induced kidney injury in Chinese critically ill pediatric patients

Background: Drug-induced acute kidney injury (DIKI) is a common adverse drug reaction event but is less known in pediatric patients. The study explored the DIKI in Chinese pediatric patients using the Pediatric Intensive Care database (PIC). Method: We screened pediatric patients with acute kidney injury (AKI) using the KDIGO criteria from the PIC and then assessed the relationship between their drugs and DIKI using the Naranjo scale. For the fifteen frequently used DIKI-suspected drugs, we divided patients into drug-exposed and non-exposed groups, using the outcome of whether DIKI was presented or not. Propensity score matching (PSM) was used to control for the effects of four confounders, age, gender, length of hospital stay, and major diagnosis. Unconditional logistic regression was used to identify statistically significant differences between the two groups. Results: A total of 238 drugs were used 1,863 times by the 81 patients with DIKI during their hospital stay. After screening the Naranjo scale to identify the top 15 suspected DIKI drugs with a high frequency of use, we found that furosemide injection (p = 0.001), midazolam injection (p = 0.001), 20% albumin prepared from human plasma injection (p = 0.004), fentanyl citrate injection (p = 0.001), compound glycyrrhizin injection (p = 0.026), vancomycin hydrochloride for intravenous (p = 0.010), and milrinone lactate injection (p = 0.009) were associated with DIKI. Conclusion: In critically ill pediatric patients, DIKI is more likely to occur after using furosemide injection, midazolam injection, 20% albumin prepared from human plasma injection, fentanyl citrate injection, compound glycyrrhizin injection, vancomycin hydrochloride for intravenous, milrinone lactate injection.

Relationship between renal and liver function with diabetic retinopathy in patients with type 2 diabetes mellitus: a study based on cross-sectional data

This study aims to explore the relationship between abnormal renal- and liver-function and diabetic retinopathy (DR) in patients with type 2 diabetes mellitus (T2DM). A total of 994 T2DM patients who received inpatient treatment in the Endocrinology Department of Henan Province People’s Hospital were included in the study. Logistic regression was performed to identify the relationship between abnormal renal and liver function with DR. Receiver operator characteristic analysis was performed to explore the efficacy of risk factors in predicting DR. Higher urine albumin [OR(95%CI) = 3.344(1.921–5.822), P < 0.001] and urine albumin/creatinine ratio [OR (95%CI) = 2.901(1.911–5.822), P < 0.001] were closely related to the occurrence of DR. People with low TP had a 1.624-times higher risk (95%CI: 1.008–2.617) of developing DR than those with normal total protein (P = 0.046). The more risk factors that are present, the greater the risk of DR. For every one-point incremental increase in the risk-factor score, the risk of DR increased by 31.0% (P < 0.001). The area under receiver operating curve of risk-factor score was 0.839 (0.812, 0.866), with a sensitivity of 81.9% and a specificity of 74.8%. The risk of developing DR increased with an increased risk-factor score. These findings are potentially valuable for DR screening and early diagnosis in patients with T2DM.

Outcome prediction for acute kidney injury among hospitalized children via eXtreme Gradient Boosting algorithm

Acute kidney injury (AKI) is common among hospitalized children and is associated with a poor prognosis. The study sought to develop machine learning-based models for predicting adverse outcomes among hospitalized AKI children. We performed a retrospective study of hospitalized AKI patients aged 1 month to 18 years in the Second Xiangya Hospital of Central South University in China from 2015 to 2020. The primary outcomes included major adverse kidney events within 30 days (MAKE30) (death, new renal replacement therapy, and persistent renal dysfunction) and 90-day adverse outcomes (chronic dialysis and death). The state-of-the-art machine learning algorithm, eXtreme Gradient Boosting (XGBoost), and the traditional logistic regression were used to establish prediction models for MAKE30 and 90-day adverse outcomes. The models’ performance was evaluated by split-set test. A total of 1394 pediatric AKI patients were included in the study. The incidence of MAKE30 and 90-day adverse outcomes was 24.1% and 8.1%, respectively. In the test set, the area under the receiver operating characteristic curve (AUC) of the XGBoost model was 0.810 (95% CI 0.763–0.857) for MAKE30 and 0.851 (95% CI 0.785–0.916) for 90-day adverse outcomes, The AUC of the logistic regression model was 0.786 (95% CI 0.731–0.841) for MAKE30 and 0.759 (95% CI 0.654–0.864) for 90-day adverse outcomes. A web-based risk calculator can facilitate the application of the XGBoost models in daily clinical practice. In conclusion, XGBoost showed good performance in predicting MAKE30 and 90-day adverse outcomes, which provided clinicians with useful tools for prognostic assessment in hospitalized AKI children.

Diffusion kurtosis imaging and arterial spin labeling for the noninvasive evaluation of persistent post-contrast acute kidney injury

OBJECTIVE

We investigated whether diffusion kurtosis imaging (DKI) and arterial spin labeling (ASL) facilitated the assessment of serial alterations in persistent post-contrast acute kidney injury (PC-AKI).

MATERIALS AND METHODS

We randomly divided 24 rats into four PC-AKI groups (days 1, 3, 7, and 13, n = 6/group), with an additional six control animals. We conducted functional magnetic resonance imaging (MRI), diffusion kurtosis imaging (DKI), and arterial spin-labeling (ASL) analyses. Mean kurtosis (MK), axial kurtosis (Ka), mean diffusivity (MD), fractional anisotropy (FA), radial kurtosis (Kr), and renal blood flow (RBF) maps were normalized to baseline (prior to contrast injection) to calculate adjusted △RBF, △MK, △Ka, △MD, △FA, and △Kr values. We also investigated urinary neutrophil gelatinase associated lipocalin (NGAL), serum cystatin C (CysC), aquaporin-2 (AQP2), hypoxia-inducible factor-1 (HIF-1α), and histological indices.

RESULTS

In the inner stripe of the outer medulla, when compared with controls, decreased △FA and △MD levels were observed on days 1, 3, and 7, and a distinct elevation in △MK and △Kr on days 1-13, and a persistent decrease in △RBF on days 1-13, and a prominent increase in △Ka on days 7 and 13 in PC-AKI animals (all p < 0.05). △Ka and △MK were positively correlated with AQP-2 (r = 0.8086, p < 0.0001 and r = 0.7314, p < 0.0001, respectively), and △RBF was highly correlated with HIF-1α (r = -0.7592, p < 0.0001). Moreover, both CysC and NGAL were significantly elevated in PC-AKI animals when compared with controls from days 1-13 (all p < 0.05). Renal histological data indicated severe tubular and glomerular injury at days 1-13 in all PC-AKI groups.

CONCLUSION

ASL and DKI may be noninvasively and longitudinally used to detect PC-AKI and predict further outcomes.

Predictive value of aspartate aminotransferase-to-alanine aminotransferase ratio for contrast-associated acute kidney injury in patients undergoing elective percutaneous coronary intervention

BACKGROUND

Pre-procedure liver insufficiency has been demonstrated as a poor prognostic factor after percutaneous coronary intervention (PCI). Recent research discovered that the aspartate aminotransferase-to-alanine aminotransferase ratio (De-Ritis ratio) reflects the severity of liver insufficiency and was associated with adverse outcomes. We aim to evaluate the predictive value of the De-Ritis ratio for contrast-associated acute kidney injury (CA-AKI) and long-term mortality in patients undergoing elective PCI.

METHODS

We retrospectively enrolled 5780 consenting patients undergoing elective PCI between January 2012 and December 2018. CA-AKI was defined as an increase in serum creatinine ≥0.3 mg/dl or ≥50% within 48 h after the administration of contrast media.

RESULTS

The incidence of CA-AKI was 6.3% (n = 363). The De-Ritis ratio >1.30 was identified as the best cut-off value for CA-AKI prediction. The De-Ritis ratio showed an area under the curve (AUC) of 0.636 [95% confidence interval (CI): 0.605-0.667] in predicting CA-AKI, which was significantly greater than alanine aminotransferase (p<0.001) and aspartate aminotransferase (p = 0.012) alone. Furthermore, compared to currently recognized liver function assessment tools, the predictive value of the De-Ritis ratio on CA-AKI was similar to the MELD score (AUC: 0.636 vs 0.626, p = 0.631) and higher than the MELD-XI score (AUC: 0.636 vs 0.561, p<0.001). Multivariate logistic analysis showed that the De-Ritis ratio >1.30 was independently associated with CA-AKI (odds ratio=1.551, 95% CI: 1.185-2.030, p = 0.001). The addition of the De-Ritis ratio to the fully adjusted logistic regression model has significant incremental effects on the risk prediction for CA-AKI with a continuous net reclassification improvement of 0.395 (p<0.001) and an integrated discrimination improvement of 0.005 (p = 0.018). Additionally, the De-Ritis ratio >1.30 was significantly associated with long-term mortality (hazard ratio=1.285, 95% CI: 1.007-1.641, p = 0.044).

CONCLUSIONS

The De-Ritis ratio was an independent risk factor for CA-AKI and long-term mortality in patients undergoing elective PCI.

Emergency angiography for trauma patients and potential association with acute kidney injury

BACKGROUND

Angiography has been conducted as a hemostatic procedure for trauma patients. While several complications, such as tissue necrosis after embolization, have been reported, little is known regarding subsequent acute kidney injury (AKI) due to contrast media. To elucidate whether emergency angiography would introduce kidney dysfunction in trauma victims, we compared the incidence of AKI between patients who underwent emergency angiography and those who did not.

METHODS

A retrospective cohort study was conducted using a nationwide trauma database (2004-2019), and adult trauma patients were included. The indication of emergency angiography was determined by both trauma surgeons and radiologists, and AKI was diagnosed by treating physicians based on a rise in serum creatinine and/or fall in urine output according to any published standard criteria. Incidence of AKI was compared between patients who underwent emergency angiography and those who did not. Propensity score matching was conducted to adjust baseline characteristics including age, comorbidities, mechanism of injury, vital signs on admission, Injury Severity Scale (ISS), degree of traumatic kidney injury, surgical procedures, and surgery on the kidney, such as nephrectomy and nephrorrhaphy.

RESULTS

Among 230,776 patients eligible for the study, 14,180 underwent emergency angiography. The abdomen/pelvis was major site for angiography (10,624 [83.5%]). Embolization was performed in 5,541 (43.5%). Propensity score matching selected 12,724 pairs of severely injured patients (median age, 59; median ISS, 25). While the incidence of AKI was rare, it was higher among patients who underwent emergency angiography than in those who did not (140 [1.1%] vs. 67 [0.5%]; odds ratio = 2.10 [1.57-2.82]; p < 0.01). The association between emergency angiography and subsequent AKI was observed regardless of vasopressor usage or injury severity in subgroup analyses.

CONCLUSIONS

Emergency angiography in trauma patients was probably associated with increased incidence of AKI. The results should be validated in future studies.

Framing Cause-Effect Relationship of Acute Coronary Syndrome in Patients with Chronic Kidney Disease

The main causes of death in patients with chronic kidney disease (CKD) are of cardiovascular nature. The interaction between traditional cardiovascular risk factors (CVRF) and non-traditional risk factors (RF) triggers various complex pathophysiological mechanisms that will lead to accelerated atherosclerosis in the context of decreased renal function. In terms of mortality, CKD should be considered equivalent to ischemic coronary artery disease (CAD) and properly monitored. Vascular calcification, endothelial dysfunction, oxidative stress, anemia, and inflammatory syndrome represents the main uremic RF triggered by accumulation of the uremic toxins in CKD subjects. Proteinuria that appears due to kidney function decline may initiate an inflammatory status and alteration of the coagulation—fibrinolysis systems, favorizing acute coronary syndromes (ACS) occurrence. All these factors represent potential targets for future therapy that may improve CKD patient’s survival and prevention of CV events. Once installed, the CAD in CKD population is associated with negative outcome and increased mortality rate, that is the reason why discovering the complex pathophysiological connections between the two conditions and a proper control of the uremic RF are crucial and may represent the solutions for influencing the prognostic. Exclusion of CKD subjects from the important trials dealing with ACS and improper use of the therapeutical options because of the declined kidney functioned are issues that need to be surpassed. New ongoing trials with CKD subjects and platelets reactivity studies offers new perspectives for a better clinical approach and the expected results will clarify many aspects.

Is intravenous iodinated contrast medium administration really harmful in hospitalized acute kidney injury patients: a propensity score-matched study

OBJECTIVES

To evaluate the effects of intravenous iodinated contrast medium (ICM) administration on the deterioration of renal function (DRF), new renal replacement therapy (RRT) induction and mortality of hospitalized acute kidney injury (AKI) patients.

METHODS

Adult hospitalized patients undergoing a contrast-enhanced or unenhanced CT scan within 7 days after AKI diagnosis from January 2015 to December 2019 were identified in this retrospective study. Propensity score matching was performed. Outcomes in 7 and 30 days after CT scan were compared between the contrast and non-contrast groups. Additional analyses were also performed in patients stratified by SCr levels at AKI diagnosis, times and time of CT scan, and in patients without chronic kidney disease or RRT requirement prior to CT scan.

RESULTS

In total, 1172 pairs were generated after 1:1 propensity score matching from 1336 cases exposed to ICM and 2724 unexposed. No significant differences were found in the outcomes between the two groups: DRF, 7.8% vs 9.0% (odds ratio (OR) 0.83, 95% confidence interval (CI) 0.62-1.11) in 7 days, 5.1% vs 5.4% (OR 0.93, 95%CI 0.64-1.34) in 30 days; new RRT induction, 2.3% vs 3.3% (OR 0.72,95%CI 0.43-1.18) in 7 days, 4.2% vs 4.5% (OR 0.95,95%CI 0.64-1.41) in 30 days; and mortality, 3.9% vs 4.8% (OR 0.83,95%CI 0.56-1.22) in 7 days, 9.0% vs 10.2% (OR 0.88,95%CI 0.68-1.15) in 30 days. Subset analyses showed similar results.

CONCLUSION

Intravenous ICM administration during AKI duration did not increase the risks of DRF, new RRT induction, and mortality in 7 and 30 days after CT scan.

KEY POINTS

• Intravenous ICM administration in hospitalized AKI patients does not increase the risks of deterioration of renal function, RRT induction, and mortality in 7 and 30 days after CT scan. • The effects of intravenous ICM on adverse outcomes are minimal even in AKI patients with high level of SCr values or multiple CT scans.

Acute kidney disease in hospitalized acute kidney injury patients

Background

Acute kidney injury (AKI) and chronic kidney disease (CKD) have become worldwide public health problems, but little information is known about the epidemiology of acute kidney disease (AKD)—a state in between AKI and CKD. We aimed to explore the incidence and outcomes of hospitalized patients with AKD after AKI, and investigate the prognostic value of AKD in predicting 30-day and one-year adverse outcomes.

Methods

A total of 2,556 hospitalized AKI patients were identified from three tertiary hospitals in China in 2015 and followed up for one year.AKD and AKD stage were defined according to the consensus report of the Acute Disease Quality Initiative 16 workgroup. Multivariable regression analyses adjusted for confounding variables were used to examine the association of AKD with adverse outcomes.

Results

AKD occurred in 45.4% (1161/2556) of all AKI patients, 14.5% (141/971) of AKI stage 1 patients, 44.6% (308/691) of AKI stage 2 patients and 79.6% (712/894) of AKI stage 3 patients. AKD stage 1 conferred a greater risk of Major Adverse Kidney Events within 30 days (MAKE30) (odds ratio [OR], 2.36; 95% confidence interval 95% CI [1.66–3.36]) than AKD stage 0 but the association only maintained in AKI stage 3 when patients were stratified by AKI stage. However, compared with AKD stage 0, AKD stage 2–3 was associated with higher risks of both MAKE30 and one-year chronic dialysis and mortality independent of the effects of AKI stage with OR being 31.35 (95% CI [23.42–41.98]) and 2.68 (95% CI [2.07–3.48]) respectively. The association between AKD stage and adverse outcomes in 30 days and one year was not significantly changed in critically ill and non-critically ill AKI patients. The results indicated that AKD is common among hospitalized AKI patients. AKD stage 2–3 provides additional information in predicting 30-day and one-year adverse outcomes over AKI stage. Enhanced follow-up of renal function of these patients may be warranted.

Long-term consequences of acute kidney injury: a narrative review

The incidence of acute kidney injury (AKI) has increased in the past decades. AKI complicates up to 15% of hospitalizations and can reach up to 50-60% in critically ill patients. Besides the short-term impact of AKI in patient outcomes, several studies report the association between AKI and adverse long-term outcomes, such as recurrent AKI episodes in 25-30% of cases, hospital re-admissions in up to 40% of patients, an increased risk of cardiovascular events, an increased risk of progression of chronic kidney disease (CKD) after AKI and a significantly increased long-term mortality. Despite the long-term impact of AKI, there are neither established guidelines on the follow-up care of AKI patients, nor treatment strategies to reduce the incidence of sequelae after AKI. Only a minority of patients have been referred to nephrology post-discharge care, despite the evidence of improved outcomes associated with nephrology referral by addressing cardiovascular risk and risk of progression to CKD. Indeed, AKI survivors should have specialized nephrology follow-up to assess kidney function after AKI, perform medication reconciliation, educate patients on nephrotoxic avoidance and implement strategies to prevent CKD progression. The authors provide a comprehensive review of the transition from AKI to CKD, analyse the current evidence on the long-term outcomes of AKI and describe predisposing risk factors, highlight the importance of follow-up care in these patients and describe the current therapeutic strategies which are being investigated on their impact in improving patient outcomes.

Diabetes Mellitus as a Risk Factor for Progression from Acute Kidney Injury to Acute Kidney Disease: A Specific Prediction Model

PURPOSE

Acute kidney injury is very common in hospitalized patients and carries a significant risk of mortality. Although timely intervention may improve patient prognosis, studies on the development of acute kidney disease in patients with acute kidney injury remain scarce. Thus, we constructed a prediction model to identify patients likely to develop acute kidney disease.

PATIENTS AND METHODS

Among 474 patients screened for eligibility, 261 were enrolled and randomly divided into training (185 patients) and independent validation cohorts (76 patients). Least absolute shrinkage and selection operator regression and multivariate logistic regression analyses were used to select features and build a nomogram incorporating the selected predictors: diabetes, anemia, oliguria, and peak creatinine. Calibration, discrimination, and the clinical usefulness of the model were assessed using calibration plots, the C-index, receiver operating characteristic curves, and decision curve analysis.

RESULTS

Diabetes was significantly associated with the presence of AKD. Peak creatinine, oliguria, and anemia also contributed to the progression of acute kidney injury. The model displayed good predictive power with a C-index of 0.834 and an AUC of 0.834 (95% confidence interval (CI): 0.773-0.895) in the training cohort and a C-index of 0.851 and an AUC of 0.851 (95% CI: 0.753-0.949) in the validation cohort. The calibration curves also showed that the model had a medium ability to predict acute kidney disease risk. Decision curve analysis showed that the nomogram was clinically useful when interventions were decided at the possibility threshold of 22%.

CONCLUSION

This novel prediction nomogram may allow for convenient prediction of acute kidney disease in patients with acute kidney injury, which may help to improve outcomes.