A Cohort Study to Analyze the Risk of Venous Thromboembolism Mortality in Patients Admitted to the General Medicine Department, Tan Tock Seng Hospital, Singapore

ABSTRACT

The purpose of this study was to assess the risk of venous thromboembolism (VTE) in patients admitted to the Tan Tock Seng Hospital (TTSH), Singapore during October and November 2009. The primary outcome assessed was mortality due to VTE, or development of deep vein thrombosis or pulmonary embolism (PE) within 3 months from the day of admission. Both univariate and multivariate analyses were performed for all-cause mortality and deaths associated with PE. Seven hundred twenty-one patients admitted to the 5th floor of the General Medicine Department, TTSH, during the 2 months were analyzed. There were 368 (51.04%) female patients and 353 (48.96%) male patients. As per race distribution, 566 (78.50%) patients were Chinese, 100 (13.86%) patients were Malaysians, 46 (6.38%) patients were Indians, and 9 (1.26%) were other races. Four hundred ninety-two (68.24%) were independent for activities of daily living (ADL) and 229 (31.76%) were dependent for all ADL. There were in all 42 deaths. There were definite PE deaths in 2 (4.76%) patients, probable PE deaths in 3 (7.14%) patients, and suspected PE deaths in 8 (19.05%) patients. Twenty (47.62%) deaths were due to pneumonia, 3 (7.14%) deaths were due to urinary tract infections, and 4 (9.52%) deaths were due to other infections. Two (4.76%) deaths were due to myocardial infarction. The risk of VTE was high in acutely ill patients admitted to the General Medicine Department, TTSH, Singapore. The factors that predispose patients to a very high risk are ADL dependence, acute heart failure, past history of VTE, or if they are clinically dehydrated and have acute renal failure. This warrants increased awareness and need for VTE prophylaxis.

KEYWORDS

Venous thromboembolism - mortality - Singapore - pulmonary embolism

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