COMPARISON OF EFFECTS OF
PRAVASTATIN AND COMBINED HORMONE REPLACEMENT THERAPY ON COAGULATION AND
FIBRINOLYSIS RE Peverill*, S Davis, R
Goldstat, A Newman, E Malan and JJ Smolich, Centre for Heart and Chest
Research, Department of Medicine, Monash Medical Centre and Monash University,
Clayton and Jean Hailes Centre, Clayton, Victoria. Randomised studies indicate
that statins reduce the risk of coronary events, while observational studies
suggest that hormone replacement therapy (HRT) has a similar benefit in
postmenopausal women. A proportion of the HRT effect has been attributed to
favourable effects on serum lipoproteins and HRT has been proposed as an
effective alternative to statin therapy. The effects of statins and HRT on coagulation and
fibrinolysis may also be important in influencing the frequency of coronary
events, but the relative effects of HRT and statins on coagulation and
fibrinolytic processes are unclear. Accordingly, a double blind study was
performed in postmenopausal women with hypercholesterolaemia who were
randomised to pravastatin 20mg (n=25) or combined HRT with 1mg estradiol and
0.5mg norethisterone (n=25). Plasma levels of fibrinogen, soluble fibrin (SF; a
marker of fibrin generation) and D-dimer (a marker of breakdown of cross-linked
fibrin) were measured at baseline and after 6 months of treatment. Baseline 6
months P Fibrinogen HRT 2.99
(1.61-3.78) 2.64
(1.92-3.61) NS
Fibrinogen Pravastatin 2.86
(1.57-5.62) 2.62
(1.83-4.3) <0.05 SF HRT 1.56
(0.06-6.23) 2.91
(0.14-18.16) <0.05 SF Pravastatin 1.64
(0.06-5.72) 2.11
(0.07-7.95) NS D-dimer HRT 16.8
(0-77.9) 17.2
(0.5-78.4) NS D-dimer Pravastatin 29.2
(6.6-112.0) 18.1
(0.2-59.5) <0.05 Results are expressed as median (range). Units are: Fibrinogen (g/L),
SF (mg/mL), D-dimer (ng/mL) These results indicate that
statins and HRT have different effects on coagulation and fibrinolysis, with
the most important difference being an adverse effect of combined HRT on fibrin
generation.
