ABOUT THIS COLLECTION

The International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) (2001-2005) was a prospective cohort study of physician practices in the provision of prophylaxis against venous thromboembolism (VTE) in hospitalized medical patients. Key endpoints included type and duration of prophylaxis as well as death, clinically apparent VTE, and bleeding within 3 months of hospital discharge. This registry enrolled over 15,000 patients from 56 hospitals in 11 countries. The IMPROVE VTE risk score calculator and bleeding risk score calculator have been developed into multi-platform applications for use at the patient’s bedside. This collection showcases publications about the project and project research.

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Recently Published

  • Predictive and Associative Models to Identify Hospitalized Medical Patients at Risk for Venous Thromboembolism

    Spyropoulos, Alex C.; Anderson, Frederick A. Jr.; Fitzgerald, Gordon; Decousus, Herve; Pini, Mario; Chong, Beng H.; Zotz, Rainer B.; Bergmann, Jean-Francois; Tapson, Victor F.; Froehlich, James B.; et al. (2011-09-26)
    BACKGROUND: Acutely ill hospitalized medical patients are at risk for venous thromboembolism (VTE). We assessed the incidence of VTE in the observational IMPROVE study, and derived VTE risk-assessment scores at admission and associative VTE scores during hospitalization. METHODS: Data from 15,156 medical patients were analyzed to determine the cumulative incidence of clinically observed VTE over 3 months after admission. Multiple regression analysis identified factors associated with VTE risk. RESULTS: Of the 184 patients who developed symptomatic VTE, 76 had pulmonary embolism and 67 lower-extremity DVT. Cumulative VTE incidence was 1.0%; 45% of events occurred post-discharge. Factors independently associated with VTE included: previous VTE; known thrombophilia; cancer; age >60, lower limb paralysis; immobilization >/=7 days; and admission to an intensive/coronary care unit (first four were available at admission). Points were assigned to each factor identified to give a total risk score for each patient. At admission, 67% of patients had a score >/=1. During hospitalization, 31% had a score >/=2; for a score of 2 or 3, observed VTE risk was 1.5% vs 5.7% for a score >/=4. Observed and predicted rates were similar for both models (c statistics 0.65 and 0.69, respectively. During hospitalization, a score >/=2 was associated with higher overall and VTE-related mortality. CONCLUSIONS: Weighted VTE risk scores derived from four clinical risk factors at hospital admission can predict VTE risk in acutely ill hospitalized medical patients. Scores derived from seven clinical factors during hospitalization may help us further understand symptomatic VTE risk. These scores require external validation.
  • Factors at admission associated with bleeding risk in medical patients: findings from the IMPROVE investigators

    Decousus, Herve; Tapson, Victor F.; Bergmann, Jean-Francois; Chong, Beng H.; Froehlich, James B.; Kakkar, Ajay K.; Merli, Geno J.; Monreal, Manuel; Nakamura, Mashio; Pavanello, Ricardo; et al. (2011-01-11)
    BACKGROUND: Acutely ill, hospitalized medical patients are at risk of VTE. Despite guidelines for VTE prevention, prophylaxis use in these patients is still poor, possibly because of fear of bleeding risk. We used data from the International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) to assess in-hospital bleeding incidence and to identify risk factors at admission associated with in-hospital bleeding risk in acutely ill medical patients. METHODS: IMPROVE is a multinational, observational study that enrolled 15,156 medical patients. The in-hospital bleeding incidence was estimated by Kaplan-Meier analysis. A multiple regression model analysis was performed to identify risk factors at admission associated with bleeding. RESULTS: The cumulative incidence of major and nonmajor in-hospital bleeding within 14 days of admission was 3.2%. Active gastroduodenal ulcer (OR, 4.15; 95% CI, 2.21-7.77), prior bleeding (OR, 3.64; 95% CI, 2.21-5.99), and low platelet count (OR, 3.37; 95% CI, 1.84-6.18) were the strongest independent risk factors at admission for bleeding. Other bleeding risk factors were increased age, hepatic or renal failure, ICU stay, central venous catheter, rheumatic disease, cancer, and male sex. Using these bleeding risk factors, a risk score was developed to estimate bleeding risk. CONCLUSIONS: We assessed the incidence of major and clinically relevant bleeding in a large population of hospitalized medical patients and identified risk factors at admission associated with in-hospital bleeding. This information may assist physicians in deciding whether to use mechanical or pharmacologic VTE prophylaxis.
  • Venous thromboembolism prophylaxis in acutely ill hospitalized medical patients: findings from the International Medical Prevention Registry on Venous Thromboembolism

    Tapson, Victor F.; Decousus, Herve; Pini, Mario; Chong, Beng H.; Froehlich, James B.; Monreal, Manuel; Spyropoulos, Alex C.; Merli, Geno J.; Zotz, Rainer B.; Bergmann, Jean-Francois; et al. (2007-09-19)
    BACKGROUND: Evidence-based guidelines recommend that acutely ill hospitalized medical patients who are at risk of venous thromboembolism (VTE) should receive prophylaxis. Our aim was to characterize the clinical practices for VTE prophylaxis in acutely ill hospitalized medical patients enrolled in the International Medical Prevention Registry on Venous Thromboembolism (IMPROVE). METHODS: IMPROVE is an ongoing, multinational, observational study. Participating hospitals enroll the first 10 consecutive eligible acutely ill medical patients each month. Patient management is determined by the treating physicians. An analysis of data on VTE prophylaxis practices is presented. RESULTS: From July 2002 to September 30, 2006, 15,156 patients were enrolled from 52 hospitals in 12 countries, of whom 50% received in-hospital pharmacologic and/or mechanical VTE prophylaxis. In the United States and other participating countries, 52% and 43% of patients, respectively, should have received prophylaxis according to guideline recommendations from the American College of Chest Physicians (ACCP). Only approximately 60% of patients who either met the ACCP criteria for requiring prophylaxis or were eligible for enrollment in randomized clinical trials that have shown the benefits of pharmacologic prophylaxis actually received prophylaxis. Practices varied considerably. Intermittent pneumatic compression was the most common form of medical prophylaxis utilized in the United States, although it was used very rarely in other countries (22% vs 0.2%, respectively). Unfractionated heparin was the most frequent pharmacologic approach used in the United States (21% of patients), with low-molecular-weight heparin used most frequently in other participating countries (40%). There was also variable use of elastic stockings in the United States and other participating countries (3% vs 7%, respectively). CONCLUSIONS: Our data suggest that physicians' practices for providing VTE prophylaxis to acutely ill hospitalized medical patients are suboptimal and highlight the need for improved implementation of existing evidence-based guidelines in hospitals.