Summary
Prothrombin is a key factor in blood clotting, a process intimately involved in thrombotic
disease. We assessed prothrombin levels and G20210A genotype in a case-control study
within the Cardiovascular Health Study. Cases included angina, myocardial infarction,
stroke, and the presence of MRI-detectable infarcts (n ≈ 250 each). Populationbased
controls free of clinical cardiovascular disease (CVD) (n ≈ 500) and a subset free
of clinical and subclinical CVD (n ≈ 250) were used for comparison. The 20210 A allele,
frequency 2.9%, was associated with higher mean prothrombin levels: 166.3 vs. 139.5
µg/ml (P <0.001). Significant correlates of prothrombin included gender, plasma lipids,
other vitamin K-dependent proteins, and inflammatory markers, but not race, smoking,
hypertension, diabetes, measures of subclinical CVD, or markers of procoagulant activity.
Compared to controls, neither genotype nor prothrombin level was associated with any
CVD case group. We conclude that, in the elderly, neither prothrombin level nor 20210
genotype were associated with either CVD risk factors or events. This is consistent
with the lack of association of prothrombin levels with measures of underlying CVD
or procoagulant markers.
Keywords
Prothrombin - elderly - nested case-control study - genetic polymorphism - cardiovascular
disease