However, given the suggestive nature of our findings, further study in even larger numbers of patients is needed to clarify the impact of factor V Leiden on stroke risk in atrial fibrillation.
In particular factor V Leiden or prothrombin G20210A associated with cryptogenic stroke (P = 0.022) whereas other coagulation abnormalities did not (P = 0.140).
Of the inherited thrombophilias, factor V Leiden and the prothrombin 20210 mutation have been associated with stroke, but this association is statistically significant only in children and adults under age 40.
Single nucleotide polymorphisms of protein C, factor V (e.g., factor V Leiden), and plasminogen activator inhibitor-1 are associated with an increased risk of deep venous thrombosis, pulmonary emboli, acute myocardial infarction, and stroke.
In particular factor V Leiden or prothrombin G20210A associated with cryptogenic stroke (P = 0.022) whereas other coagulation abnormalities did not (P = 0.140).
Recently, the high prevalence of factor V Leiden in patients with stroke and a history of migraine has suggested an association between migraine and prothrombotic genetic risk factors.
It has been proposed that activated protein C resistance (APCR) due to the factor V Leiden (FVL) mutation may be a risk factor for stroke in young adults.
The odds ratios for each event with heterozygous factor V Leiden were: MI, 0.46 (95% CI 0.17 to 1.25); angina, 1.0 (95% CI 0.45 to 2.23); stroke, 0.77 (95% CI 0.35 to 1.70): TIA, 1.33 (95% CI 0.5 to 3.55); any outcome, 0.83 (95% CI 0.48 to 1.44).