Inferior vena cava filters are associated with a reduced in-hospital all-cause case fatality rate of unstable patients with acute pulmonary embolism. Whether vena cava filters are associated with a reduced case fatality rate in adults of all ages with unstable pulmonary embolism, particularly the elderly, has not been determined.Unstable patients with pulmonary embolism (in shock or ventilator dependent) 1999-2008 were identified from the Nationwide Inpatient Sample.Among 21,095 unstable patients with pulmonary embolism who received thrombolytic therapy, in-hospital all-cause case fatality rate was lower in every age group who received a vena cava filter in addition to thrombolytic therapy (P = .0012 to <.0001). Patients aged ≥81 years showed the greatest absolute reduction of case fatality rate with filters (19.3%). Among 50,210 unstable patients who did not receive thrombolytic therapy, case fatality rate also was lower in every age group who received a vena cava filter (all P <.0001). Patients aged ≥81 years with vena cava filters showed the greatest absolute risk reduction of case fatality rate (27.7%).Vena cava filters are associated with a reduced in-hospital all-cause case fatality rate in unstable adults with pulmonary embolism, irrespective of age.