Albuminuria and Dipstick Proteinuria for Predicting Mortality in Heart Failure: A Systematic Review and Meta-Analysis

Background: Research suggest that albuminuria is not only an independent risk factor for the development of heart failure but may also act as a biomarker for predicting adverse outcomes. To date, no study has synthesized evidence on its role as a prognostic indicator. Thus, the current study aimed to quantitatively assess the prognostic utility of albuminuria as well as dipstick proteinuria in predicting mortality in heart failure patients. Methods: PubMed, Embase, ScienceDirect, CENTRAL, and Google Scholar databases were searched up to October 10, 2020. All studies reporting multivariable-adjusted hazard ratios (HR) for albuminuria or dipstick proteinuria for mortality and/or hospitalization in heart failure patients were included. Results: Eleven studies were included. Seven assessed albuminuria and five assessed dipstick proteinuria. Our analysis revealed a statistically significant increased risk of all-cause mortality with microalbuminuria (HR: 1.54; 95% CI, 1.23–1.93; I(2) = 79%; p = 0.0002) and macroalbuminuria (HR: 1.76; 95% CI, 1.21–2.56; I(2) = 88%; p = 0.003) in heart failure patients. The risk of all-cause mortality and hospitalization was also significantly increased with macroalbuminuria. Microalbuminuria was associated with significantly increased cardiovascular mortality and combined cardiovascular mortality and hospitalization. Positive dipstick test for proteinuria was significantly associated with mortality in heart failure (HR: 1.54; 95% CI, 1.28–1.84; I(2) = 67%; p < 0.00001). Conclusion: Both microalbuminuria and macroalbuminuria are predictors of mortality in patients with heart failure. Dipstick proteinuria may be used as a rapid screening test to predict mortality in these patients.