With use of Medicare administrative data, 1,823 interruption of vena cava procedures performed between 1994 and 1997 were identified among beneficiaries aged 65-99 years residing in Indiana and Kentucky. In Cox proportional hazard regression models, male-to-female and nonwhite-to-white 30-day mortality ratios were adjusted for age, sex or race, weighted Charlson comorbidity score, length of hospital stay, and fatal coexisting conditions (ascertained from death certificate data).