NEW YORK (Reuters Health) – Nephropathy associated with iodinated contrast medium exposure can be fatal, physicians report in the October issue of Mayo Clinic Proceedings. However, the mortality risk is even higher when contrast is administered intravenously than when it is injected into an artery, their findings suggest.

Dr. Aaron M. From and colleagues at the Mayo Clinic in Rochester, Minnesota, studied patients who underwent contrast procedures at their site between April 2004 and March 2006. Their cohort included 809 patients who developed contrast-induced nephropathy and 2427 control subjects who did not develop the condition, matched by age, sex, prior creatinine value, diabetes, and type of radiographic study.

Thirty-day and overall mortality during mean follow-up of 16 months were 15.6% and 31.8% in the contrast-induced nephropathy group, vs 5.2% and 22.6% in the patients without contrast-induced nephropathy. Contrast-induced nephropathy was significantly associated with 30-day (adjusted odds ratio 3.37) and overall mortality (adjusted hazard ratio 1.57, p < 0.001 for both analyses).

The authors note, however, that the increased mortality risk associated with contrast-induced nephropathy was significant only among patients with stage II and III kidney disease according to creatinine clearance measurement before contrast exposure.

Moreover, the mortality associated with contrast-induced nephropathy was approximately three times higher among patients who underwent intravenous contrast administration than among those who underwent intra-arterial contrast administration.

Dr. From