Warfarin and aortic valve calcification in hemodialysis patients.
BACKGROUND
This retrospective cohort study was designed to determine the association between long-term exposure to warfarin and severity of aortic valve (AV) calcification in hemodialysis (HD) patients.


METHODS
One hundred and eight HD patients underwent a study-specific echocardiogram. A grading scheme was used to classify AV calcification as none, mild, moderate and severe. Demographic, biochemical and medication data were abstracted by chart review.


RESULTS
One hundred and eight subjects were enrolled. A minority had no calcification (n=17, 15.7%), the majority had mild calcification (n=62, 57.4%), and fewer had calcification rated as moderate (n=16, 14.8%) or severe (n=13, 12%). Dialysis vintage was associated with severity of AV calcification (p=0.04). The 18 subjects with long-term warfarin exposure (36.7 +/- 19.7 months) were more likely to have severe AV calcification (p=0.04). The odds ratio of falling into a higher category of AV calcification following 18 months of warfarin was 3.77 (95% confidence ratio, 0.97-14.70; p=0.055). There was an association between lifetime months of warfarin exposure and severity of AV calcification (p=0.004) that was independent of dialysis vintage, calcium and calcitriol intake.


CONCLUSIONS
The data suggest that warfarin may be associated with severity of AV calcification in HD patients and support the need for prospective studies.
Holden
Rachel M
RM
Division of Nephrology, Queen's University, Kingston, Ontario, Canada. holdenr@kgh.kari.net
Sanfilippo
Anthony S
AS
Hopman
Wilma M
WM
Zimmerman
Deborah
D
Garland
Jocelyn S
JS
Morton
A Ross
AR
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage*; D001024:Aortic Valve Stenosis / Q000139:chemically induced / Q000453:epidemiology*; D002114:Calcinosis / Q000139:chemically induced / Q000453:epidemiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D006435:Renal Dialysis; D012189:Retrospective Studies; D014859:Warfarin / Q000008:administration & dosage*
D000925:Anticoagulants; D014859:Warfarin