(HealthDay)—Contrast-induced nephropathy (CIN) is associated with long-term mortality in patients with, but not those without, chronic kidney disease (CKD), according to a study published in the Aug. 1 issue of The American Journal of Cardiology.

Mitsuru Abe, M.D., from the National Hospital Organization Kyoto Medical Center in Japan, and colleagues examined the effect of CIN on long-term mortality after in with or without CKD. Data were included for 4,371 patients who had paired serum creatinine measurements before and after percutaneous coronary intervention.

The researchers found that the incidence of CIN was 5 percent in the study cohort overall, and was 11 percent in patients with CKD and 2 percent in those without CKD (P < 0.0001) A total of 8.6 percent of patients died during a median follow-up of 42.3 months after discharge. CIN correlated with long-term mortality in the entire cohort after adjustment for prespecified confounders (hazard ratio [HR], 2.26; 95 percent confidence interval [CI], 1.62 to 2.29; P < 0.0001). CIN correlated with long-term mortality in patients with CKD (HR, 2.62; 95 percent CI, 1.91 to 3.57; P < 0.0001), but not in patients without CKD (HR, 1.23; 95 percent CI, 0.47 to 2.62; P = 0.6). These results were confirmed in sensitivity analyses.

"In conclusion, CIN was significantly correlated with long-term mortality in patients with CKD but not in those without CKD," the authors write.