Urea To Creatinine Ratio Research Articles

Role of urea to creatinine ratio in the prediction of outcomes in chronic heart failure

Abstract Background Renal function predicts events in chronic heart failure (HF). Urea to creatinine ratio (UCR) is a simple and cheap biomarker which correlates with neuroendocrine pathways. Objectives Evaluate the prognostic role of UCR in patients with chronic HF. Methodology 86 patients with chronic HF from an academic hospital were included (with reduced, mildly reduced or improved left ventricular ejection fraction). UCR was calculated at baseline, and patients were followed for a median of 360 (interquartile range 180-472) days. We plotted ROC curves for NT-proBNP and UCR and evaluated two scenarios using the Kaplan-Meier curve to determine the event-free survival. We grouped patients into four subgroups: a) UCR and NT-proBNP below the cut-off; b) UCR above and NT-proBNP below; c) UCR below and NT-proBNP above; and d) both above the cut-off. A second scenario was analysed, grouped as follows: a) UCR and NT-proBNP below; b) at least one of them above the cut-off; and c) both above the cutoff. The primary endpoint was cardiovascular death or HF hospitalisation. The level of significance was 5%. Results The mean age was 66.1±12.1y, and 60.5% were male. There were 28 events in the follow-up (32.5%). The ROC curve for UCR had an AUC of 0.75 (CI 0.64-0.86; p=0.0002) for a cut-off of 43.8 (sensitivity of 75% and specificity of 70.7%). The AUC for NT-proBNP was 0.64 (0.51-0.77; p=0.043) for a cut-off of 2010 pg/mL (sensitivity of 64.3% and specificity of 65.5%). In the Cox regression model, the UCR was the only independent predictor with HR of 1.06 per 1 unit increase (1.03-1.10; p=0.0002). UCR above cut-off (as a categorical variable) was the only independent predictor, with HR 5.34 (2.26-12.6; p=0.0001). Kaplan-Meier curves in Figures 1 and 2 show the UCR performance associated with NT-proBNP. Conclusions UCR is a simple and cheap biomarker that has been shown to have predictive power, probably due to persistent neuroendocrine activation in patients with low volume. In this population, elevated UCR added risk even in patients with low levels of NT-proBNP.

Clinical implications of admission and follow-up urea-to-creatinine ratio in patients with acute decompensated heart failure

PurposeAcute decompensated heart failure (ADHF) patients with a poor renal function have a worse prognosis. The urea-to-creatinine ratio (UCR) may be a valuable tool for assessing kidney function and stratifying patients with ADHF. We evaluated the value of an admission and follow-up UCR in predicting AKI, 28-day mortality, and rehospitalization in patients with ADHF.MethodsThis prospective research comprised sixty patients with ADHF. Based on the mean admission UCR, patients are classified into two groups: the high UCR group (UCR ≥ 42.33) and the low UCR group (UCR < 42.33). On the third day, they are categorized into high UCR and low UCR groups according to the same mean of UCR (42.33). A 28-day follow-up was implemented.ResultsThirty patients (50%) developed AKI, and nine (15%) died during follow-up. In the high UCR group, the development of AKI was considerably more significant than in the low UCR group on the 3rd day (69.2% vs. 35.2%, respectively, p = 0.010). Furthermore, the high UCR group experienced a higher death rate than the low UCR group on the 3rd day (26.9% vs. 5.8%, respectively, p = 0.024). A considerable statistical correlation was reported between UCR and eGFR on the 3rd day (p = 0.025). According to ROC, UCR on the 3rd day was a significant predictor of AKI and 28-day mortality in these patients ((AUC = 0.736 and 0.718, respectively). In contrast, UCR on admission was not a predictor of AKI or 28-day mortality (p = 0.578 and 0.305, respectively). Also, neither admission nor 3rd day UCR could predict HF readmission (p = 0.108 and 0.298, respectively). By the Kaplan–Meier curve, survival rates were highest when UCR ≤ 34.85 and reduced when UCR > 34.85 (p < 0.001).ConclusionThe follow-up UCR is a good predictor of AKI development and elevated 28-day mortality in ADHF patients. Considering its simplicity, this biomarker should be used more systematically in clinical practice.

Elevated Serum Urea-to-Creatinine Ratio and In-Hospital Death in Patients with Hyponatremia Hospitalized for COVID-19.

Hyponatremia is associated with adverse outcomes in hospitalized patients. An elevated value of the serum urea-to-creatinine ratio (UCR) has been proposed as a proxy of hypovolemia. The aim of this study was to investigate the relationship between the UCR and in-hospital death in patients hospitalized with COVID-19 and hyponatremia. We studied 258 patients admitted for COVID-19 between January 2020 and May 2021 with serum sodium at < 135 mmol/L. The primary end-point was all-cause mortality. A 5-unit increase in the serum UCR during hospital stays was associated with an 8% increase in the hazard of all-cause death (HR = 1.08, 95% CI: 1.03-1.14, p = 0.001) after adjusting for potential confounders. In patients with a UCR > 40 at baseline, a > 10 mmol/L increase in serum sodium values within the first week of hospitalization was associated with higher odds of in-hospital death (OR = 2.93, 95% CI: 1.03-8.36, p = 0.044) compared to patients who experienced a < 10 mmol/L change. This was not observed in patients with a UCR < 40. Hypovolemia developing during hospital stays in COVID-19 patients with hyponatremia detected at hospital admission bears an adverse prognostic impact. Moreover, in hypovolemic patients, a > 10 mmol/L increase in serum sodium within the first week of hospital stays may further worsen the in-hospital prognosis.

Catabolism highly influences ICU-acquired hypernatremia in a mainly trauma and surgical cohort

PurposeTo further analyse causes and effects of ICU-acquired hypernatremia. MethodsThis retrospective, single-centre study, analysed 994 patients regarding ICU-acquired hypernatremia. Non-hypernatremic patients (n = 617) were compared to early-hypernatremic (only before ICU-day 4; n = 87), prolonged-hypernatremic (before and after ICU-day 4; n = 169) and late-hypernatremic patients (only after ICU-day 4; n = 121). Trends in glomerular filtration rate (eGFR), urea-to-creatinine ratio (UCR), fraction of urea in total urine osmolality and urine sodium were compared. Risk factors for i) the development of hypernatremia and ii) mortality were determined. ResultsThirty-eight percent (n = 377) developed ICU-acquired hypernatremia. Specifically in the prolonged- and late-group, decreased eGFRs and urine sodium but increased UCR and fractions of urea in urine osmolality were present. Decreased eGFR was a risk factor for the development of hypernatremia in all groups; disease severity and increased catabolism particularly in the prolonged- and late-hypernatremic group. Increased age, SAPS-III and signs of catabolism but not the development of hypernatremia itself was identified as significant risk factor for mortality. ConclusionsLate- and prolonged-hypernatremia is highly related to an increased protein metabolism. Besides excessive catabolism, initial disease severity and a decrease in renal function must be considered when confronted with ICU-acquired hypernatremia.

Admission Hydration Status and Ischemic Stroke Outcome-Experience from a National Registry of Hospitalized Stroke Patients.

Reduced intravascular volume upon ischemic stroke (IS) admission has been associated with in-hospital complications, disability, and reduced survival. We aimed to evaluate the association of the urea-to-creatinine ratio (UCR) with disability or death at discharge, length of stay, in-hospital complications, and mortality during the first year. Using a national registry, we identified hospitalized IS patients without renal failure. Disability or death at discharge, length of stay, in-hospital complications, and mortality during the first year were studied by UCR, and associations between UCR levels and each outcome were assessed adjusting for age, sex, stroke severity, comorbidities, use of statins, and use of diuretics. In total, 2212 patients were included. Levels (median (25–75%)) for the main study variables were: urea 5.16 (3.66–6.83) mmol/L; creatinine 80 (64–92) µmol/L; and UCR 65 (58–74). Levels of UCR were significantly higher in patients with disability or death at discharge (p < 0.0001), those with complications during hospitalization (p = 0.03), those with infection during hospitalization (p = 0.0003), and those dead at 1 year (p < 0.0001). Analysis by UCR quartile showed that rates of disability or death at discharge, infections, complications overall, and death at 1 year in patients with UCR in the 4th quartile were significantly higher than in others. Risk-factor-adjusted analysis by UCR quartiles demonstrated an inconsistent independent association between UCR and disability or death after ischemic stroke. A high 1-year mortality rate was observed in IS patients with elevated UCR, yet this finding was not statistically significant after controlling for risk factors. Our study shows inconsistent associations between hydration status and poor functional status at discharge, and no association with length of stay, in-hospital complications (infectious and overall), and 1-year mortality.

Novel methods to identify and measure catabolism.

Assess current potential catabolism-biomarkers to characterize patients developing prolonged critical illness. A raised urea-to-creatinine ratio (UCR) during critical illness is negatively associated with muscle mass with greater increases in UCR seen patients developing persistent critical illness. Similarly, sarcopenia index (a ratio of creatinine to cystatin-c concentrations) correlates well to muscle mass in intensive care populations. Elevated growth/differentiation factor-15 (GDF-15) has been inconsistently associated with muscle loss. Although GDF-15 was a poor marker of feeding tolerance, it has been associated with worse prognosis in intensive care. UCR is an available and clinically applicable biomarker of catabolism. Similarly, sarcopenia index can be used to assess muscle mass and indirectly measure catabolism based on readily available biochemical measurements. The utility of novel biomarkers, such as GDF-15 is less established.

Factors determining renal impairment in unilateral ureteral colic secondary to calcular disease: a prospective study.

To evaluate all possible risk factors that can cause impairment of overall renal function in patients with unilateral ureteral calculus and a normal contralateral kidney. This is a prospective study of 90 patients who presented to our institute complaining of renal colic secondary to unilateral ureteral calculus. All patients were evaluated with a thorough history, physical examination, and laboratory and radiological investigations including renal function testing, urine analysis, non-contrast computed topography, and radionucleotide scan. Patients were divided into two groups according to their calculated creatinine clearance using the Modification of Diet in Renal Disease (MDRD) formula. Group I (favorable group) had a creatinine clearance >60 ml/min, while group II (unfavorable group) had a creatinine clearance <60 ml/min. The patients' mean age ± SD was 38.8 ± 11.4 years. Group I included 54 patients (60 %), while group II included 36 patients (40 %). On univariate analysis, factors that were associated with overall renal function impairment were patients' age, urea-to-creatinine ratio (UCR), use of nonsteroidal anti-inflammatory drugs, stone location, and presence of obstruction. However, using binary logistic regression analysis, only patients' age, UCR, and presence of obstruction sustained statistical significance in association with renal function impairment. The study of factors that help explain the presence of renal impairment in patients with unilateral ureteral calculus is important in the clinical setting. Patients' age, urea-to-creatinine ratio, and degree of obstruction seem to be significantly associated with overall renal function impairment.

Increased serum urea to creatinine ratio and its negative correlation with arterial pressure in canine babesiosis.

The increase of the serum urea to creatinine ratio (UCR) was observed in dogs infected with Babesia canis. Previous studies have suggested that decrease of blood pressure can be one of the reasons for this phenomenon. In this work statistically significant increase of the UCR was observed in dogs with babesiosis. Comparison of the UCR between 23 azotaemic dogs and 25 non-azotaemic dogs infected with Babesia canis showed statistically significantly higher mean of the UCR in azotaemic dogs. Correlations between UCR and systolic, diastolic and mean arterial pressure (SAP, DAP and MAP) in 48 dogs infected with B. canis were negative (UCR and SAP: r = -0.3909; UCR and DAP: r = -0.3182; UCR and MAP: r = -0.3682) and statistically significant (p < 0.05). This result may indicate contribution of hypotension in the increase of the UCR in canine babesiosis. However, the correlations were not high, and there was no statistically significant correlation between UCR and arterial pressures in azotaemic dogs. Thus, it seems that decrease of blood pressure in dogs with babesiosis explains only partially the cause of increased UCR in infected dogs. The other authors suggested hyperureagenesis and myocardial injury as a potential reason for the increased UCR in canine babesiosis. Thus, further studies are needed to determine causes of increased UCR in dogs with babesiosis, especially on the connection between UCR changes and the concentrations of plasma cardiac troponins and ammonia, and the occurrence of occult blood on fecal examination.

Laboratory prediction of the requirement for renal replacement in acute falciparum malaria

BackgroundAcute renal failure is a common complication of severe malaria in adults, and without renal replacement therapy (RRT), it carries a poor prognosis. Even when RRT is available, delaying its initiation may increase mortality. Earlier identification of patients who will need RRT may improve outcomes.MethodProspectively collected data from two intervention studies in adults with severe malaria were analysed focusing on laboratory features on presentation and their association with a later requirement for RRT. In particular, laboratory indices of acute tubular necrosis (ATN) and acute kidney injury (AKI) that are used in other settings were examined.ResultsData from 163 patients were available for analysis. Whether or not the patients should have received RRT (a retrospective assessment determined by three independent reviewers) was used as the reference. Forty-three (26.4%) patients met criteria for dialysis, but only 19 (44.2%) were able to receive this intervention due to the limited availability of RRT. Patients with impaired renal function on admission (creatinine clearance < 60 ml/min) (n = 84) had their laboratory indices of ATN/AKI analysed. The plasma creatinine level had the greatest area under the ROC curve (AUC): 0.83 (95% confidence interval 0.74-0.92), significantly better than the AUCs for, urinary sodium level, the urea to creatinine ratio (UCR), the fractional excretion of urea (FeUN) and the urinary neutrophil gelatinase-associated lipocalcin (NGAL) level. The AUC for plasma creatinine was also greater than the AUC for blood urea nitrogen level, the fractional excretion of sodium (FeNa), the renal failure index (RFI), the urinary osmolality, the urine to plasma creatinine ratio (UPCR) and the creatinine clearance, although the difference for these variables did not reach statistical significance.ConclusionsIn adult patients with severe malaria and impaired renal function on admission, none of the evaluated laboratory indices was superior to the plasma creatinine level when used to predict a later requirement for renal replacement therapy.