Background: Oxidative stress caused by contrast medium is thought to be one of the main mechanisms of contrast-induced acute kidney injury. A prospective study was conducted to evaluate the relationship between oxidative stress caused by contrast agent administration and long-term renal function.
Methods and results: Thirty-six consecutive patients who underwent coronary angiography were enrolled. Urinary F2-isoprostane, a marker of oxidative stress, was measured at baseline and 24h after angiography, and serum creatinine was measured at baseline, 24h and 1 year after the procedure. The change in estimated glomerular filtration rate (eGFR) at 1 year after angiography correlated significantly with the change in eGFR at 24h after angiography (r=0.729, P<0.001). We also found a significant correlation between the increase in urinary F2-isoprostane at 24h and the decrease in eGFR at 1 year (r=0.439, P=0.022). In multivariate analysis, the decrease in eGFR at 1 year after coronary angiography correlated with the increase in F2-isoprostane at 24h after angiography as well as the decrease in eGFR at 24h after angiography (P=0.039 and P<0.001, respectively).
Conclusions: Contrast-induced nephrotoxicity might be transient; however, an early decrease in eGFR and increase in oxidative stress are associated with chronic renal insufficiency. Careful long-term follow-up and adequate medical intervention are necessary for these patients.