Relationship between serum uric acid levels and urinary albumin excretion in patients with heart failure.
OBJECTIVE
Hyperuricaemia is a constant finding in patients with heart failure (HF). Upregulated xanthine-oxidase activity seems to contribute to progression of the disease through the production of oxidative stress and the development of vascular and endothelial dysfunction. On this basis we speculated that in HF serum uric acid levels correlated with a reliable marker of endothelial dysfunction as urinary albumin excretion.


METHODS
Fifty-three patients with HF underwent assessment of serum uric acid, N-terminal probrain natriuretic peptide (NT-proBNP), glomerular filtration rate (GFR), other metabolic parameters and determination of urinary albumin concentration (UAC) in a morning urine sample.


RESULTS
In univariate analysis there is a direct correlation between serum uric acid levels and log UAC (r = 0.43, P < 0.01); uric acid correlates also positively with log NT-proBNP (r = 0.31, P < 0.05) and negatively with log-GFR (r = -0.38, P < 0.01). In stepwise regression analysis serum uric acid emerged as the only predictor of increased UAC (standardized coefficient = 0.42, P = 0.001) independent of other clinical determinants and metabolic factors.


CONCLUSIONS
Serum uric acid represents the strongest predictor of elevated UAC in HF. Regression of albuminuria may be a simple target to verify the efficacy of xanthine-oxidase inhibition in these patients.
Pinelli
Massimiliano
M
Department of Internal Medicine IV, Azienda Ospedaliera-Universitaria Pisana, Pisa, Italy.
Bindi
Massimo
M
Moroni
Federica
F
Castiglioni
Maido
M
D000368:Aged; D000419:Albuminuria / Q000209:etiology / Q000503:physiopathology / Q000652:urine*; D015415:Biomarkers / Q000097:blood / Q000652:urine; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006333:Heart Failure / Q000150:complications / Q000378:metabolism*; D006801:Humans; D033461:Hyperuricemia / Q000209:etiology / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood; D009391:Nephelometry and Turbidimetry; D010446:Peptide Fragments / Q000097:blood; D011379:Prognosis; D011498:Protein Precursors; D012720:Severity of Illness Index; D014527:Uric Acid / Q000097:blood*
D015415:Biomarkers; D010446:Peptide Fragments; D011498:Protein Precursors; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain; D014527:Uric Acid