Randomized, placebo-controlled trial of dalteparin for the prevention of venous thromboembolism in acutely ill medical patients.
BACKGROUND
Considerable variability exists in the use of pharmacological thromboprophylaxis among acutely ill medical patients, partly because clinically relevant end points have not been fully assessed in this population. We undertook an international, multicenter, randomized, double-blind, placebo-controlled trial using clinically important outcomes to assess the efficacy and safety of dalteparin in the prevention of venous thromboembolism in such patients.


RESULTS
Patients (n=3706) were randomly assigned to receive either subcutaneous dalteparin 5000 IU daily or placebo for 14 days and were followed up for 90 days. The primary end point was venous thromboembolism, defined as the combination of symptomatic deep vein thrombosis, symptomatic pulmonary embolism, and asymptomatic proximal deep vein thrombosis detected by compression ultrasound at day 21 and sudden death by day 21. The incidence of venous thromboembolism was reduced from 4.96% (73 of 1473 patients) in the placebo group to 2.77% (42 of 1518 patients) in the dalteparin group, an absolute risk reduction of 2.19% or a relative risk reduction of 45% (relative risk, 0.55; 95% CI, 0.38 to 0.80; P=0.0015). The observed benefit was maintained at 90 days. The overall incidence of major bleeding was low but higher in the dalteparin group (9 patients; 0.49%) compared with the placebo group (3 patients; 0.16%).


CONCLUSIONS
Dalteparin 5000 IU once daily halved the rate of venous thromboembolism with a low risk of bleeding.
Unité de Pharmacologie Clinique, Université Claude Bernard Lyon I, Lyon, France. al@upcl.univ-lyon1.fr
Alain
A
Leizorovicz
Alexander T
AT
Cohen
Alexander G G
AG
Turpie
Carl-Gustav
CG
Olsson
Paul T
PT
Vaitkus
Samuel Z
SZ
Goldhaber
D000208:Acute Disease / Q000401:mortality / Q000628:therapy*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D017985:Dalteparin / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D003645:Death, Sudden / Q000453:epidemiology; D004311:Double-Blind Method; D005260:Female; D006470:Hemorrhage / Q000139:chemically induced; D017052:Hospital Mortality; D006801:Humans; D007103:Immobilization / Q000009:adverse effects*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011655:Pulmonary Embolism / Q000453:epidemiology / Q000517:prevention & control; D012306:Risk; D013923:Thromboembolism / Q000517:prevention & control*; D019851:Thrombophilia / Q000188:drug therapy* / Q000209:etiology; D016896:Treatment Outcome; D020246:Venous Thrombosis / Q000517:prevention & control*
D000925:Anticoagulants; D017985:Dalteparin