Avaliação da incidência de tromboembolismo venoso e efetividade da tromboprofilaxia em pacientes clínicos agudamente enfermos

Abstract

Introduction: Venous thromboembolism is a condition that affects approximately 10 million people/year worldwide and is the third leading cause of cardiovascular-related death. Its incidence is higher in hospitalized patients, and thromboprophylaxis prescription is effective but often underused. Risk assessment models (RAM) should be used to guide thromboprophylaxis. Objective: To assess the incidence of VTE, adequacy, and effectiveness of thromboprophylaxis in acutely ill medical patients, using the IMPROVE7 (International Medical Prevention Registry on Venous Thromboembolism) RAM as a predictive score for thromboembolic risk. Method: A prospective cohort study was conducted in a general hospital, and included adult patients hospitalized in medical units, from August/2017 to September/2018, and excluded those admitted in psychiatric or gynecological wards, direct admissions to Intensive Care Unit or Coronary Unit, hospitalizations lasting less than 48 hours, and patients admitted for the treatment of venous thromboembolic events or under anticoagulation. The IMPROVE7 was used to assess thromboembolic risk. The adequacy of thromboprophylaxis was evaluated during hospital stay. The study outcomes consisted of objectively confirmed VTE events and death related to pulmonary embolism (PE). Cumulative incidence was estimated using the Kaplan Meier (1-KM) estimator and Competing Risk (CR), with death unrelated to VTE as a competing event. This study has been conducted before the COVID-19 pandemics. Results: A literature review was conducted before the study initiation when we identified gaps and the lack of consistent definitions in several concepts. There was a variation in the onset, duration, and appropriateness of thromboprophylaxis, as well as in the definition of risk factors such as immobilization. Additionally, the study included 2,380 patients who were assessed for the risk of VTE. The median age of the participants was 70 years, with an average hospital stay of 10 days. Women comprised 56.5% of the included population. Of the evaluated patients, 86.3% were classified as low risk for VTE. A total of 30 patients (1.3%) were had objectively-confirmed VTE. Regarding the adequacy of thromboprophylaxis, 61.2% received inadequate thromboprophylaxis. The overall mortality rate during the study period was 14,0% (n = 328/2,343). Two cases (0.6%) had PE objectively confirmed before death. Most deaths (91.2%) were attributed to causes other than pulmonary embolism. Cumulative incidence of VTE by the 1-KM estimator was 2.2% (95% CI 0.6%-3.8%) and by CR 2.0% (95% CI 0.9%-3.8%) when the competing risk analysis, death not related to VTE, was considered. Conclusion: The cumulative incidence of VTE was 2.0% when the competing risk analysis, corroborating with the other studies. Despite guidance, thromboprophylaxis was inadequate in most patients. To our concern, this is the first prospective cohort study to evaluate incidence of VTE in hospitalized clinical patients in Brazil.