Abstract P266: Elevated Hemostasis Biomarkers are Associated with Incident Cognitive Decline in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study
Introduction. Cognitive decline (CD) causes substantial health and social burdens. Vascular risk factors, including elevated CRP, are associated with CD. A procoagulant state may be one mechanism for this association. Residence in the stroke belt region of the US is an independent risk factor for CD. We hypothesized that hemostasis biomarkers would be associated with risk of CD and mediate regional differences in CD.
Methods. REGARDS is a cohort of 30,239 black and white Americans ≥ 45 years old, 56% from the stroke belt and 44% from the other contiguous states. We used a nested case-control design to determine associations of D-dimer, fibrinogen, factor VIII and protein C with incident CD in REGARDS. Cases were 495 participants free of stroke and cognitive impairment at baseline who scored >1.57 SD below age-race-sex-education predicted scores on ≥2 of 3 cognitive tests at their most recent assessment. Controls were 587 non-cases from a stratified cohort random sample. We calculated odds ratios (OR) of CD by biomarker level using weighted logistic regression.
Results. D-dimer > clinical cutpoint 0.50 μg/mL, fibrinogen >90th percentile (≥502 mg/dL), and factor VIII>90th percentile (≥168%) were each significantly associated with incident CD in univariate models (Table); however, adjustment for demographic and vascular risk factors, CRP, and use of aspirin, statins or warfarin attenuated these associations. Protein C was not associated with CD. Having at least two elevated biomarkers (excluding protein C) was associated with CD in both univariate and multivariable models (Table). The association of hemostasis biomarkers with CD did not differ by race or region. Stroke belt residence was a risk factor for CD (ORadj 1.60 CI 1.17, 2.40) but this OR was not reduced by adding biomarker levels to the models.
Conclusion. Elevated levels of D-dimer, fibrinogen, and factor VIII may be useful in identifying those at increased risk of CD, especially considered in combination.
- © 2013 by American Heart Association, Inc.