Background: Increased urinary excretion of albumin is an early sign of kidney damage and a risk factor for progressive cardiovascular and renal diseases and heart failure. There is, however, only limited information on the prevalence and prognostic role of urinary albumin excretion in patients with established chronic heart failure.
Methods and results: A total of 2131 patients enrolled in 76 sites participating in the GISSI-Heart Failure trial provided a first morning spot sample of urine at any of the clinical visits scheduled in the trial to calculate the urinary albumin-to-creatinine ratio. The relation between log-transformed urinary albumin-to-creatinine ratio and all-cause mortality (428 deaths, time from urine collection to event or censoring) was evaluated with Cox multivariable models adjusted for all significant risk factors at the time of urine collection, in the study population, and in patients without diabetes or hypertension. Almost 75% of the patients had normal urinary albumin excretion, but 19.9% had microalbuminuria (30 to 299 mg/g creatinine) and 5.4% had overt albuminuria (>or=300 mg/g). There was a progressive, significant increase in the adjusted rate of mortality in the study population (hazard ratio, 1.12; 95% CI, 1.05 to 1.18 per 1-U increase of log(urinary albumin-to-creatinine ratio), P=0.0002) and in the subgroup of patients without diabetes or hypertension. Randomized treatments (n-3 polyunsaturated fatty acids or rosuvastatin) had no major impact on albumin excretion.
Conclusions: Independently of diabetes, hypertension, or renal function, elevated albumin excretion is a powerful prognostic marker in patients with chronic heart failure.