Clinicians React to FDA's Gadolinium Warnings
The rate at which patients with renal disease are undergoing magnetic resonance (MR) studies using gadolinium-based contrast agents decreased dramatically since 2006, when the FDA issued its first warning regarding a link between the use of these agents and development of nephrogenic system fibrosis (NSF), a recent study found.
The study examined data from patients receiving medical care in the U.S. Department of Veterans Affairs Health Care System. From July 2005 to September 2008, a total of 1,080,536 MR studies were performed. Of these, 406,003 (38%) were gadolinium-enhanced MR studies (GE-MR).
From the first FDA warning in June 2006 to the most recent available data (fourth quarter of 2008), the rate of GE-MR use was essentially unchanged for patients with a glomerular filtrate rate (GFR) above 60 mL/min/1.73 m2. The rate declined, however, by 71% for those with a GFR of 15-30 and 61% for patients with a GFR of 15 or less, according to a report in the American Journal of Kidney Diseases (2010;56:458-467). The rate declined 81% among subjects who had received recent dialysis (98% for a subset of patients with acute kidney injury).
Meanwhile, the rate of non-enhanced MR use increased for all GFR categories, except for patients who had received recent dialysis. The rate rose by 19% for patients with a GFR of 15-30 and by 71% for those with a GFR of 15 or below.
In addition, during the same time frame, the proportion of GE-MR studies with serum creatinine measurements obtained within one month, three months, and six months prior to the study increased by 99%, 59%, and 41%, respectively, researchers from VA Boston Healthcare System reported.
In a related development, the FDA in September announced that it is requiring that gadolinium-based contrast agents carry new warnings on their labels about the risk of NSF if administered to certain patients with kidney disease.
Three such agents—Magnevist, Omniscan, and Optimark—will be described as inappropriate for use among patients with acute kidney injury or chronic severe kidney disease, according to the FDA. All GBCA labels will emphasize the need to screen patients to detect these types of kidney problems prior to administration.
NSF is a condition involving the formation of excess fibrous connective tissue in the skin, joints, eyes, and internal organs. Symptoms can include scaling, hardening and tightening of the skin, red or dark patches on the skin, and stiffness. NSF can lead to death, particularly if it involves organs, the FDA said.