LAUSR

Editor's Note Continued High Rates of IVC Filter Use After US Food and Drug Safety Warning Inferior vena cava (IVC) filters have drawn my attention since I learned about their serious risks from Nicholson and colleagues’ careful study1 of the high fracture rate of (Bard Recovery) IVC filters in 2010. At that time, I commented, “Remarkably, these filters, which are placed inside the IVC, were considered Class II by the FDA—the same risk category of mercury thermometers—and received approval without any clinical data of safety and effectiveness identified in their 510(k) clearances.”2 Publication of the Nicholson study prompted the US Food and Drug Administration (FDA) to review the adverse event database and issue a safety warning in 2010 related to reports of 921 adverse events since 2005 and reminded doctors to remove these retrievable filters. Despite the FDA warning, most retrievable filters are never retrieved3. In addition, evidence suggests that the longer the filter is in place the higher the chance of fracture.1 I learned more about the (lack of) evidence of benefit from IVC filters from the summary of Prasad et al.4 Furthermore, studies show that many IVC filters are placed in persons who are able to take anticoagulants, which is the appropriate firstline treatment for prevention of pulmonary embolism. Indeed, in a chart review of 3 hospitals in Massachusetts only 50% of IVC filters were placed for appropriate indications.5 In addition, the use of IVC filters has expanded to include other groups of patients for whom there is no evidence of benefit, such as prophylactic use prior to bariatric surgery. The report by Reddy et al6 in this issue documents continued unacceptably high rates of IVC filter use after the FDA warning and continued lack of evidence of benefit. As is true for many treatments that were later shown to be harmful and have been abandoned, such as antiarrhythmic medications for patients following myocardial infarction, or metal-on-metal hips, some argue that it is impossible to do a randomized clinical trial of IVC filters because practice patterns are set.7 As is true for many invasive treatments, IVC filter use is much higher in the United States than any other country. In the absence of evidence of benefit and definite harms, IVC filters get a Less Is More designation. There should be a moratorium on their use unless or until there are data showing efficacy greater than risk.