Improved inferior vena cava (IVC) filters have led to liberalization of the indications for insertion. Increased use, however, has been followed with a potential for unwarranted insertion. There are only sparse data on trends in the use of IVC filters in patients with pulmonary embolism (PE), patients with deep venous thrombosis (DVT) alone, and patients at high risk. We analyzed the National Hospital Discharge Survey (NHDS) database for such trends.
We used data from the NHDS, which is based on a national probability sample of discharges from short-stay nonfederal hospitals in 50 states and the District of Columbia. The numbers of sampled patients with DVT, PE, and IVC filters were determined from the International Classification of Diseases, Ninth Revision, Clinical Modification codes at discharge.
The number of patients who had IVC filters increased from 2000 in 1979 to 49 000 in 1999. In 1999, 45% of IVC filter insertions were in patients with DVT alone, 36% were in patients with PE, and 19% were in patients who presumably were at high risk but did not have DVT or PE listed as a discharge code. The use of IVC filters was more frequent in northeastern states than in western states (P = .01).
The use of IVC filters increased markedly during the last 2 decades in patients with PE, patients with DVT alone, and patients at risk who had neither PE nor DVT. Randomized controlled trials may lead to improved risk stratification and limit the number of unnecessary filter insertions.