Beta-receptor blockade decreases elevated plasma levels of factor VIII:C in patients with deep vein thrombosis.
BACKGROUND
An elevated plasma level of factor VIII:C (FVIII:C) is a strong and dose-dependent risk factor for venous thromboembolism (VTE). The cause of elevated FVIII:C in patients with thrombophilia is as yet unknown. FVIII:C increases significantly after infusion of epinephrine, vasopressin or physical exercise. The aim of the present study was to investigate whether beta-receptor blockade will lower sustained elevated FVIII:C in patients with VTE.


RESULTS
Two cohorts of patients with documented deep vein thrombosis and an elevated FVIII:C (>175 IU dL(-1)) and healthy volunteers, were studied. One cohort was treated with the beta-receptor blocker, whereas the other cohort served as non-treatment controls. The patient treatment group and healthy volunteers were given 40 mg propranolol, thrice daily, for 14 days. The mean baseline level of FVIII:C was 220 IU dL(-1) and 102 IU dL(-1) in patients and healthy volunteers, respectively. After 2 weeks of propranolol a significant 23% reduction of FVIII:C (- 52 IU dL(-1); 95%CI:[-65; -39]) compared with no change over time in the patient no- treatment group (-1.8 IU dL(-1); 95%CI:[-34; 30]). After discontinuation of propranolol FVIII:C returned to its initial high level. In healthy volunteers propranolol had no effect on the plasma concentration of FVIII:C.


CONCLUSIONS
This study demonstrates that in patients with VTE a sustained elevated FVIII:C concentration can be decreased with the use of propranolol. This observation may be of potential clinical relevance, since it has been shown that each increase of 10 IU dL(-1) in FVIII:C concentration enhanced the risk of a recurrent VTE by 24%.
Hoppener
M R
MR
Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, The Netherlands. m.r.hoppener@amc.uva.nl
Kraaijenhagen
R A
RA
Hutten
B A
BA
Büller
H R
HR
Peters
R J G
RJ
Levi
M
M
D000328:Adult; D015331:Cohort Studies; D005169:Factor VIII / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011433:Propranolol / Q000494:pharmacology; D012306:Risk; D012307:Risk Factors; D013923:Thromboembolism / Q000188:drug therapy / Q000517:prevention & control; D019851:Thrombophilia / Q000097:blood; D013997:Time Factors; D020246:Venous Thrombosis / Q000097:blood*; D014841:von Willebrand Factor / Q000096:biosynthesis
D014841:von Willebrand Factor; D005169:Factor VIII; D011433:Propranolol