Measurement of D-dimer as aid in risk evaluation of VTE in elderly patients hospitalized for acute illness: a prospective, multicenter study in China.

PURPOSE: Advanced age and hospitalization are associated with increasing risk of venous thromboembolic (VTE) events. The aim of this study was to investigate whether elevated D-dimer levels could predict VTE events in elderly patients hospitalized for acute illness.
METHODS: 458 consecutive patients (65% men; mean age, 77 ± 7 years) who were older than 60 years, immobilized for ≥ 3 days, and hospitalized for heart failure, respiratory failure, acute ischemic stroke, or acute infectious disease without pharmacological prophylaxis or recent major surgery, were enrolled. Elevated D-dimer levels were defined as > 500 ng/ml. VTE events included symptomatic VTE within 90 days or asymptomatic deep venous thrombosis screened by compression ultrasonography at enrollment and 3-week follow-up. The association between baseline D-dimer levels and subsequent VTE events, adjusted for age, sex, ethnicity, body mass index, co-morbidities, and acute disease status, was assessed using multivariate Cox proportional hazard models.
RESULTS: 49.1% (n = 225) of patients had elevated baseline D-dimer levels, and of these patients, 14.2% (n = 32) developed VTE during the 90-day follow-up. In contrast,only 5.6% (n = 13) of patients with normal D-dimer levels developed VTE. Multivariate analysis showed that patients with elevated D-dimer levels had a 3.2-fold increased risk of developing VTE (95% confidence interval, 1.5-6.5; P = 0.002) in comparison with patients with normal levels.
CONCLUSIONS: In elderly patients who were hospitalized for acute medical illness, elevated D-dimer levels are associated with subsequent VTE events. Our data suggest that measurement of D-dimer, a widely-performed objective test, may help clinicians address high-risk individuals for VTE.