Venous thromboembolic and bleeding risk in population with obesity hospitalized for an acute medical illness receiving enoxaparin for thromboprophylaxis.

BACKGROUND

Patients with obesity hospitalized for acute medical illness are at increased venous thromboembolism (VTE) risk, but evidence on predictors of VTE and major bleeding (MB) to optimize individual risk stratification and thromboprophylaxis remains limited, in particular for patients with extreme obesity.

OBJECTIVES

This study assessed pharmacologic regimen, event rates, and predictors for VTE and MB among hospitalized medical patients with obesity receiving thromboprophylaxis using enoxaparin.

METHODS

Patients with body mass index (BMI) of ≥30 kg/m2 hospitalized for acute medical illness who received thromboprophylaxis with enoxaparin were selected from the Optum database. Event rates over a 90-day follow-up after enoxaparin initiation were estimated via the Kaplan-Meier method. Factors associated with outcome events were identified via Cox proportional hazard models.

RESULTS

Among 58,186 eligible patients, 17,398 (30%) had a BMI of >40 kg/m2; 56.9% received high-dose enoxaparin (>40 mg), and 42.8% received the standard dose (≤40 mg). The median duration of enoxaparin prophylaxis (3 days) was shorter than the length of the hospitalization (4 days). The 90-days cumulative incidence was 3.2% (95% CI, 3.1-3.4) for VTE and 1.8% (95% CI, 1.7-1.9) for MB. The highest VTE rates were observed in patients with cancer-related hospitalizations (7.8%). A history of VTE and MB were the strongest predictors of VTE (HR, 4.1; 95% CI, 3.6-4.7) and MB (HR, 2.8; 95% CI, 2.0-3.7), respectively.

CONCLUSION

Acutely ill patients with obesity received enoxaparin for shorter duration than their hospitalization, with over half receiving a high-dose adjustment by weight. The VTE rates were nonnegligible in this population and exceed MB rates across illness subgroups, suggesting a need for individualized risk stratification to optimize thromboprophylaxis.