Elevated urinary albumin concentration predicts worse clinical outcomes in hospitalized acute decompensated heart failure patients

Diagnostic value and utility of commonly used biomarkers of cardiac and renal function in cardiorenal syndromes: a narrative review

Cardiorenal syndrome (CRS), first defined in 2004 as a consequence of the interactions between the kidneys and other circulatory departments leading to acute heart failure, has since been recognized as a complex clinical entity that is hard to define, diagnose and classify. The framework for the classification of CRS according to pathophysiologic background was laid out in 2008, dividing CRS into five distinct phenotypes. However, determining the timing of individual organ injuries and making a diagnosis of either renal or cardiac failure remains an elusive task. In clinical practice, the diagnosis and phenotyping of CRS is mostly based on using laboratory biomarkers in order to directly or indirectly estimate the degree of end-organ functional decline. Therefore, a well-educated clinician should be aware of the effects that the reduction of renal and cardiac function has on the diagnostic and predictive value and properties of the most commonly used biomarkers (e.g. troponins, N-terminal pro-brain natriuretic peptide, serum creatinine etc). They should also be acquainted, on a basic level, with emerging biomarkers that are specific to either the degree of glomerular integrity (cystatin C) or tubular injury (neutrophil gelatinase-associated lipocalin). This narrative review aims to provide a scoping overview of the different roles that biomarkers play in both the diagnosis of CRS and the prognosis of the disease in patients who have been diagnosed with it, along with highlighting the most important pitfalls in their interpretation in the context of impaired renal and/or cardiac function.

Microalbuminuria and mortality in individuals with coronary heart disease: A meta-analysis of a prospective study

AIM

Microalbuminuria has been elevated as an outcome predictor in cardiovascular medicine. However, due to the small number of studies investigating the association of microalbuminuria and mortality in the coronary heart disease (CHD) population, the prognosis value of microalbuminuria in CHD remains under debate. The objective of this meta-analysis was to investigate the relationship between microalbuminuria and mortality in individuals with CHD.

METHOD

A comprehensive literature search was performed using Pubmed, EuroPMC, Science Direct, and Google Scholar from 2000 to September 2022. Only prospective studies investigating microalbuminuria and mortality in CHD patients were selected. The pooled effect estimate was reported as risk ratio (RR).

RESULTS

5176 patients from eight prospective observational studies were included in this meta-analysis. Individuals with CHD have a greater overall risk of all-cause mortality (ACM) [rR = 2.07 (95% CI = 1.70-2.44); p = 0.0003; I2 = 0.0%] as well as cardiovascular mortality (CVM) [rR = 3.23 (95% CI = 2.06-4.39), p < 0.0001; I2 = 0.0%]. Subgroup analysis based on follow-up duration and a subset of CHD patients were similarly associated with an increased risk of ACM.

CONCLUSION

This meta-analysis indicates that microalbuminuria is associated with a higher risk of mortality in individuals with CHD. Microalbuminuria can serve as a predictor of poor outcomes in CHD patients.

Urine albumin-to-creatinine ratio on admission predicts early rehospitalization in patients with acute decompensated heart failure

Detecting high-risk patients for early rehospitalization is crucial in heart failure patient care. An association of albuminuria with cardiovascular events is well known. However, its predictive impact on rehospitalization for acute decompensated heart failure (ADHF) remains unknown. In this study, 190 consecutive patients admitted due to ADHF between 2017 and April 2019 who underwent urinalysis were enrolled. Among them, 140 patients from whom urine albumin-to-creatinine ratio (UACR) was measured with spot urine samples on admission were further analyzed. The association between UACR and rehospitalization due to HF during 1 year after discharge was evaluated. The mean age of 140 participants was 77.6 years and 55% were men. Only 18% (n = 25) of patients presented with normoalbuminuria (UACR < 30 mg/g∙creatinine), whereas 59% (n = 83) and 23% (n = 32) showed microalbuminuria (UACR 30-300 mg/g·creatinine) and macroalbuminuria (UACR > 300 mg/g·creatinine), respectively. The level of UACR on admission was correlated with the risk of subsequent rehospitalization due to HF (p = 0.017). The receiver operating characteristic analysis indicated that the best cut-off values for the UACR and B-type natriuretic peptide (BNP) levels to predict ADHF rehospitalization were 50 mg/g·creatinine and 824 pg/ml, respectively. When the patients were divided into four groups using both cut-off values, the individual predictive impacts of UACR and BNP on rehospitalization were comparable. Patients with both elevated UACR and BNP levels had a higher rate of HF rehospitalization than those with elevated BNP levels alone (p < 0.05). The combination of both values enabled more accurate prediction of HF rehospitalization than BNP levels alone. In conclusion, UACR could be a new useful biomarker to predict HF rehospitalization in patients with ADHF, especially in combination with the levels of BNP, and should be further evaluated in a prospective study.

Elevated urinary albumin concentration predicts worse clinical outcomes in hospitalized acute decompensated heart failure patients

Objective

To investigate the prognostic value of elevated urinary albumin concentration (UAC) in hospitalized acute decompensated heart failure (ADHF) patients.

Methods

We measured UAC at baseline in 1818 hospitalized ADHF patients who were admitted to our Heart Failure Center. All patients were followed up for a median period of 937.5 days. The primary endpoint was a composite of all‐cause death or heart transplantation (HTx) or left ventricular assist device (LVAD) implantation.

Results

In total, 41.5% of ADHF patients had albuminuria (UAC ≥ 20 mg/L). The median value of UAC was 15.5 mg/L. A total of 679 patients died or underwent HTx/LVAD during follow‐up. The median UAC was significantly lower in non‐HTx/LVAD survivors (14.3 mg/L) than in those who died or underwent HTx/LVAD (18.0 mg/L, P < 0.001). Compared with patients without albuminuria (reference, n = 1064), those with albuminuria had a 1.47‐fold higher risk of all‐cause death or HTx/LVAD (95% confidence interval [CI]:1.26–1.71, P < 0.001), with hazard ratios (HRs) of 1.42 (95% CI: 1.21–1.66) and 1.74 (95% CI: 1.33–2.26) in patients with microalbuminuria (20 mg/L ≤ UAC < 200 mg/L, n = 617) and macroalbuminuria (UAC ≥ 200 mg/L, n = 137), respectively (both P < 0.001). After adjustment for significant clinical risk factors, the albuminuria group had a higher risk of primary adverse events than the non‐albuminuria group (HR = 1.28, 95% CI: 1.09–1.50, P = 0.003), with HRs of 1.27 [95% CI: 1.07–1.49] and 1.36 [95% CI: 1.01–1.84] in patients with microalbuminuria and macroalbuminuria, respectively (P = 0.006 and P = 0.041). The adjusted risk of primary adverse events also increased with the degree of albuminuria in the test for trend (HR = 1.21, 95% CI: 1.06–1.37, P for trend = 0.004). In the subgroup analysis, albuminuria had a significantly greater prognostic value for patients with left ventricular ejection fraction ≥ 40%, eGFR ≥ 60 mL/min/1.73 m², BUN/creatinine ratio ≥ 20 or NT‐proBNP < 2098 pg/mL.

Conclusion

The presence of albuminuria evaluated by UAC predicts adverse clinical outcomes in hospitalized ADHF patients.