Elevated Blood Urea Nitrogen to Serum Albumin Ratio Is an Adverse Prognostic Predictor for Patients Undergoing Cardiac Surgery

Association of Serum Blood Urea Nitrogen to Albumin Ratio with in-Hospital Mortality in Patients with Acute Ischemic Stroke: A Retrospective Cohort Study of the eICU Database

Background

Albumin (ALB) and blood urea nitrogen (BUN) are both associated with the prognosis of acute ischemic stroke (AIS). A recent prognostic marker, the BUN/ALB ratio (BAR), has been suggested as a simple and sensitive method to predict certain acute diseases.

Aims

To determine the predictive value of BAR in relation to the risk of in-hospital mortality among AIS patients.

Study Design

Retrospective cohort study.

Methods

Cox regression analysis was employed to assess the relationship between in-hospital mortality and BAR, with hazard ratios (HRs) and 95% confidence intervals. Subgroup analysis of acute pulmonary embolism, acute myocardial infarction (AMI), thrombolysis, thrombectomy, and septic shock was performed to further examine this relationship. The predictive value of BAR and BAR multivariate models for in-hospital mortality was evaluated and compared to BUN, ALB, the Acute Physiology and Chronic Health Evaluation IV (APACHE IV) score, and the Sequential Organ Failure Assessment Score (SOFA).

Results

Among the 1,635 eligible patients, 226 (13.81%) died during hospitalization. An elevated serum BAR level was associated with an increased in-hospital mortality risk (HR: 1.3) after covariates were adjusted. Additionally, this positive association was observed in patients without AP, AMI, thrombolysis, history of thrombectomy, or septic shock (all; p < 0.05). The efficacy of the BAR multivariate model in predicting in-hospital mortality among AIS patients was superior to that of both APACHE IV and SOFA, with an area under the curve of 0.87.

Conclusion

Serum BAR exhibits the potential to identify AIS patients with high mortality risk, which may contribute to enhanced disease surveillance and risk stratification.

Prognostic value of albumin-based indices for mortality after heart failure: a systematic review and meta-analysis

BACKGROUND

Albumin-based indices have been used to predict mortality after heart failure (HF). We hereby examined the utility of albumin-globin ratio, lactate-albumin ratio, blood urea nitrogen (BUN)-albumin ratio, fibrinogen-albumin ratio, and albumin-bilirubin score (ABS) in predicting mortality after HF.

METHODS

We searched Embase, PubMed, Web of Science, and Scopus databases up to 2nd October 2024 for studies examining association between albumin-based indices and mortality after HF. A random-effect meta-analysis was conducted using multivariate adjusted data to calculate pooled hazard ratio (HR) with 95% confidence intervals (CI). Subgroup analysis was conducted for short-term (< 90 days) and long-term mortality (≥ 1 year) where possible.

RESULTS

There were seven studies on ABS, three studies each on BUN-albumin and fibrinogen-albumin ratio, and two studies each for albumin-globulin and lactate-albumin ratio. Meta-analysis showed that ABS was predictive of both short-term (HR: 2.01 95% CI: 1.01, 4.00 I2 = 62% p = 0.05) and long-term (HR: 1.36 95% CI: 1.05, 1.76 I2 = 49% p = 0.02) mortality after HF. Meta-analysis also showed that high fibrinogen-albumin ratio (HR: 1.12 95% CI: 1.09, 1.14 I2 = 0% p < 0.00001), BUN-albumin ratio (HR: 1.84 95% CI: 1.28, 2.64 I2 = 64% p = 0.001), and lactate-albumin ratio (HR: 1.84 95% CI: 1.68, 2.01 I2 = 0% p < 0.00001) were predictors of mortality after HF.

CONCLUSION

Very low quality of evidence indicates that albumin-based indices can predict mortality after HF. ABS was found to independently predict short and long-term mortality after HF. Other ratios like the albumin-globin ratio, lactate-albumin ratio, BUN-albumin ratio, and fibrinogen-albumin ratio were also found to predict mortality after HF albeit with limited data.

Blood urea nitrogen to serum albumin ratio as a new indicator of disease severity and prognosis in idiopathic pulmonary artery hypertension

BACKGROUND

Emerging evidence has shown that the blood urea nitrogen to serum albumin ratio (BAR) is associated with the severity and prognosis of heart failure. However, its role in idiopathic pulmonary arterial hypertension (IPAH) remains unclear. This study investigated the associations between BAR and functional status, echocardiographic findings, hemodynamics, and long-term outcomes among patients with IPAH.

METHODS

This study included consecutive patients who underwent right heart catheterization (RHC) and were diagnosed with IPAH between January 2013 and January 2018 at Fuwai Hospital. The primary outcome was the worsening of clinical symptoms. Spearman correlation coefficients were used to evaluate the association between the BAR and established markers of IPAH severity. Receiver operating characteristic (ROC) curve analysis was used to determine BAR's optimal cut-off and predictive performance. Kaplan-Meier analysis and Cox proportional hazard models assessed the relationship between BAR and clinical worsening.

RESULTS

A total of 340 patients with IPAH were included in this study. BAR correlated with well-validated variables that reflected the severity of IPAH, such as World Health Organization functional class, 6-min walk distance, N-terminal pro-brain natriuretic peptide (NT-proBNP) level, mixed venous oxygen saturation, and cardiac index. Kaplan-Meier curves indicated that patients with BAR＞3.80 had a significantly higher clinical worsening rate (log-rank test, P < 0.001) than those with BAR≤3.80. Multivariate Cox analysis showed that BAR could independently predict clinical worsening [hazard ratio(HR):2.642, 95 % confidence interval (CI):1.659-4.208, P < 0.001]. In addition, BAR provided additional predictive value for the European Society of Cardiology (ESC)/European Respiratory Society (ERS) risk assessment score.

CONCLUSIONS

BAR reflects disease severity and is independently associated with the prognosis of patients with IPAH.

Blood urea nitrogen to serum albumin ratio as a new prognostic indicator in type 2 diabetes mellitus patients with chronic kidney disease

Chronic kidney disease (CKD) is often a common comorbidity in critically ill patients with type 2 diabetes mellitus (T2DM). This study explored the relationship between blood urea nitrogen to serum albumin ratio (BAR) and mortality in T2DM patients with CKD in intensive care unit (ICU). Patients were recruited from the Medical Information Mart database, retrospectively. The primary and secondary outcomes were 90-day mortality, the length of ICU stay, hospital mortality and 30-day mortality, respectively. Cox regression model and Kaplan-Meier survival curve were performed to explore the association between BAR and 90-day mortality. Subgroup analyses were performed to determine the consistency of this association. A total of 1920 patients were enrolled and divided into the three groups (BAR < 9.2, 9.2 ≤ BAR ≤ 21.3 and BAR > 21.3). The length of ICU stay, 30-day mortality, and 90-day mortality in the BAR > 21.3 group were significantly higher than other groups. In Cox regression analysis showed that high BAR level was significantly associated with increased greater risk of 90-day mortality. The adjusted HR (95%CIs) for the model 1, model 2, and model 3 were 1.768 (1.409-2.218), 1.934, (1.489-2.511), and 1.864, (1.399-2.487), respectively. Subgroup analysis also showed the consistency of results. The Kaplan-Meier survival curve analysis revealed similar results as well that BAR > 21.3 had lower 90-day survival rate. High BAR was significantly associated with increased risk of 90-day mortality. BAR could be a simple and useful prognostic tool in T2DM patients with CKD in ICU.

Blood urea nitrogen to serum albumin ratio: a novel mortality indicator in intensive care unit patients with coronary heart disease

The blood urea nitrogen to albumin ratio (BAR) has been demonstrated as a prognostic factor in sepsis and respiratory diseases, yet its role in severe coronary heart disease (CHD) remains unexplored. This retrospective study, utilizing data from the Medical Information Mart for Intensive Care-IV database, included 4254 CHD patients, predominantly male (63.54%), with a median age of 74 years (IQR 64-83). Primary outcomes included in-hospital, 28-day and 1-year all-cause mortality after ICU admission. The Kaplan-Meier curves, Cox regression analysis, multivariable restricted cubic spline regression were employed to assess association between BAR index and mortality. In-hospital, within 28-day and 1-year mortality rates were 16.93%, 20.76% and 38.11%, respectively. Multivariable Cox proportional hazards analysis revealed associations between the increased BAR index and higher in-hospital mortality (HR 1.11, 95% CI 1.02-1.21), 28-day mortality (HR 1.17, 95% CI 1.08-1.27) and 1-year mortality (HR 1.23, 95% CI 1.16-1.31). Non-linear relationships were observed for 28-day and 1-year mortality with increasing BAR index (both P for non-linearity < 0.05). Elevated BAR index was a predictor for mortality in ICU patients with CHD, offering potential value for early high-risk patient identification and proactive management by clinicians.

Blood urea nitrogen to serum albumin ratio is associated with all-cause mortality in patients with AKI: a cohort study

Background

This study aims to investigate the relationship between blood urea nitrogen to serum albumin ratio (BAR) and all-cause mortality in patients with acute kidney injury (AKI) and evaluate the effect of BAR on the prognosis of AKI.

Methods

Adult patients with AKI admitted to the ICU in the Medical Information Mart for Intensive Care IV (MIMIC-IV) were selected in a retrospective cohort study. BAR (mg/g) was calculated using initial blood urea nitrogen (mg/dl)/serum albumin (g/dl). According to the BAR, these patients were divided into quartiles (Q1-Q4). Kaplan-Meier analysis was used to compare the mortality of the above four groups. Multivariate Cox regression analysis was used to evaluate the association between BAR and 28-day mortality and 365-day mortality. The receiver operating characteristic (ROC) curve was plotted and the area under the curve (AUC) was calculated, and the subgroup analysis was finally stratified by relevant covariates.

Results

A total of 12,125 patients with AKI were included in this study. The 28-day and 365-day mortality rates were 23.89 and 39.07%, respectively. Kaplan-Meier analysis showed a significant increase in all-cause mortality in patients with high BAR (Log-rank p < 0.001). Multivariate Cox regression analysis showed that BAR was an independent risk factor for 28-day mortality (4.32 < BAR≤7.14: HR 1.12, 95% CI 0.97-1.30, p = 0.114; 7.14 < BAR≤13.03: HR 1.51, 95% CI 1.31-1.75, p < 0.001; BAR>13.03: HR 2.07, 95% CI 1.74-2.47, p < 0.001; Reference BAR≤4.32) and 365-day mortality (4.32 < BAR≤7.14: HR 1.22, 95% CI 1.09-1.36, p < 0.001; 7.14 < BAR≤13.03: HR 1.63, 95% CI 1.46-1.82, p < 0.001; BAR>13.03: HR 2.22, 95% CI 1.93-2.54, p < 0.001; Reference BAR ≤ 4.32) in patients with AKI. The AUC of BAR for predicting 28-day mortality and 365-day mortality was 0.649 and 0.662, respectively, which is better than that of blood urea nitrogen and sequential organ failure assessment. In addition, subgroup analysis showed a stable relationship between BAR and adverse outcomes in patients with AKI.

Conclusion

BAR is significantly associated with increased all-cause mortality in patients with AKI. This finding suggests that BAR may help identify people with AKI at high risk of mortality.

The association of blood urea nitrogen to serum albumin ratio with short-term outcomes in Chinese patients with congestive heart failure: A retrospective cohort study

BACKGROUND AND AIMS

Limited evidence exists on the prognostic outcomes of the blood urea nitrogen to serum albumin ratio (B/A ratio) in congestive heart failure (CHF), particularly in developing countries with scarce heart failure epidemiological data. We aimed to investigate the association between B/A ratio and short-term outcomes in Chinese patients with CHF.

METHODS AND RESULTS

We included 1761 CHF patients with available B/A ratio data from a cohort of 2008 patients. Patients were categorized into three groups based on B/A ratio (low to high). The primary endpoint was death or readmission within 28 days, and the secondary endpoint was death or readmission within 90 days. We employed restricted cubic spline analysis, Cox proportional hazards regression, and Kaplan-Meier curves to evaluate the relationship between B/A ratio at admission and the endpoints. Even after adjusting for other variables, higher B/A ratios were associated with increased rates of 28 days and 90 days mortality or readmission (HR: 2.4, 95% CI: 1.81-3.18 and HR: 1.74, 95% CI: 1.48-2.05). Significant differences in the risks of both primary and secondary endpoints were observed among the three B/A ratio groups. The association between B/A ratio and CHF was stable in the different subgroups (all P for interaction＞0.05).

CONCLUSION

Higher B/A ratios are associated with an increased risk of short-term mortality or readmission in Chinese patients with CHF. The B/A ratio shows promise as a prognostic indicator for short-term outcomes in CHF patients.

Relationship between blood urea nitrogen to serum albumin ratio and short-term mortality among patients from the surgical intensive care unit: a population-based real-world study

BACKGROUND

Patients admitted to the surgical intensive care unit (SICU) often suffer from multi-organ dysfunction and have a high mortality rate. Therefore, finding a simple but effective clinical indicator to predict the prognosis of patients is essential to improve their survival. The aim of this study was to investigate the relationship between blood urea nitrogen to serum albumin ratio (B/A) and short-term mortality among patients from the SICU.

METHODS

All eligible adult patients admitted to the SICU from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database were recruited for this study. Participants were divided into a death group (n = 638) and a survival group (n = 2,048) based on the 90-day prognosis, and then grouped by B/A quartiles. We used restricted cubic splines (RCS) to visually analyze the correlation of B/A with 30- and 90-day risk of death. Cumulative survival rates were estimated using Kaplan-Meier survival curves according to B/A quartiles and evaluated using the log-rank test. Cox proportional risk models were developed and sensitivity analyses were performed to explore whether B/A was independently associated with short-term outcomes in SICU patients. Receiver operating characteristic (ROC) curves were analyzed to ascertain the value of B/A for prognosticating 90-day outcome.

RESULTS

A total of 2686 participants were included in the final study, and their 30-day and 90-day all-cause mortality rates were 17.61% and 23.75%, respectively. The differences in 30-day and 90-day mortality rates were statistically significant among the four groups of patients (all p < 0.001). RCS curves showed that B/A was linearly associated with the risk of 30-day and 90-day all-cause mortality in SICU patients (χ2 = 0.960, p = 0.811; χ2 = 1.940, p = 0.584). Kaplan-Meier analysis showed that the 90-day cumulative survival rate gradually decreased as B/A increased, with patients in the highest quartile of B/A having the lowest survival rate (p < 0.001). Cox regression indicated that elevated B/A (> 9.69) was an independent risk factor for 30-day and 90-day all-cause mortality in SICU patients. The analysis of ROC curves demonstrated that B/A exhibited a significant predictive ability for 90-day mortality, with an optimal threshold of 6.587, a sensitivity of 56.9%, and a specificity of 64.8%.

CONCLUSIONS

Elevated B/A (> 9.69) on admission was an independent risk factor for short-term mortality in SICU patients, and clinicians should pay more attention to this group of patients and intervene clinically at an early stage to reduce mortality.

Comparison of Prognostic Value of 10 Biochemical Indices at Admission for Prediction Postoperative Myocardial Injury and Hospital Mortality in Patients with Osteoporotic Hip Fracture

Aim: To evaluate the prognostic impact at admission of 10 biochemical indices for prediction postoperative myocardial injury (PMI) and/or hospital death in hip fracture (HF) patients. Methods: In 1273 consecutive patients with HF (mean age 82.9 ± 8.7 years, 73.5% women), clinical and laboratory parameters were collected prospectively, and outcomes were recorded. Multiple logistic regression and receiver-operating characteristic analyses (the area under the curve, AUC) were preformed, the number needed to predict (NNP) outcome was calculated. Results: Age ≥ 80 years and IHD were the most prominent clinical factors associated with both PMI (with cardiac troponin I rise) and in-hospital death. PMI occurred in 555 (43.6%) patients and contributed to 80.3% (49/61) of all deaths (mortality rate 8.8% vs. 1.9% in non-PMI patients). The most accurate biochemical predictive markers were parathyroid hormone > 6.8 pmol/L, urea > 7.5 mmol/L, 25(OH)vitamin D < 25 nmol/L, albumin < 33 g/L, and ratios gamma-glutamyl transferase (GGT) to alanine aminotransferase > 2.5, urea/albumin ≥ 2.0 and GGT/albumin ≥ 7.0; the AUC for developing PMI ranged between 0.782 and 0.742 (NNP: 1.84−2.13), the AUC for fatal outcome ranged from 0.803 to 0.722, (NNP: 3.77−9.52). Conclusions: In HF patients, easily accessible biochemical indices at admission substantially improve prediction of hospital outcomes, especially in the aged >80 years with IHD.