Prognostic value of albuminuria on cardiovascular outcomes after elective percutaneous coronary intervention

Albuminuria is the most widely evaluated marker of kidney damage. Many previous studies have demonstrated an association between the presence of albuminuria and increased cardiovascular events. However, there are limited data regarding the impact of albuminuria in patients requiring coronary revascularization. This study investigated whether the urinary albumin excretion rate could predict cardiovascular events in such a population. We enrolled 698 consecutive patients who underwent elective percutaneous coronary intervention. The baseline urinary albumin-to-creatinine ratio (ACR; mg/gCr) was measured and patients were divided into those with normoalbuminuria (ACR <30 mg/gCr), microalbuminuria (ACR 30 to 300 mg/gCr), or macroalbuminuria (ACR >300 mg/gCr). We collected data on the incidences of cardiac death and/or nonfatal myocardial infarction. We identified 389, 230, and 79 patients with normoalbuminuria, microalbuminuria, and macroalbuminuria, respectively. During follow-up (median: 1,564 days), 41 events occurred. The event-free survival rate was 89% in patients with macroalbuminuria, 92% in those with microalbuminuria, and 97% in those with normoalbuminuria, respectively (log-rank test p = 0.002). After adjustment for conventional risk factors, Cox analysis revealed hazard ratios for cardiac death and/or nonfatal myocardial infarction were 2.56 (95% CI 1.23 to 5.32, p = 0.01) in those with microalbuminuria and 4.02 (95% CI 1.59 to 10.12, p = 0.003) in those with macroalbuminuria compared with those with normoalbuminuria. In conclusion, an elevated urinary albumin excretion rate independently predicted adverse cardiovascular outcomes, with a gradual risk increase that progressed from microalbuminuria to macroalbuminuria in patients undergoing elective percutaneous coronary intervention.