July 14, 2008

BIRMINGHAM, Ala. - Nita Limdi, Pharm.D, Ph.D., MSPH, assistant professor of neurology at UAB (University of Alabama at Birmingham), has been awarded $3.6 million from the National Heart, Lung and Blood Institute, part of the National Institutes of Health, to study how genetic and environmental factors such as medications and diet influence warfarin dose and risk of bleeding complications.

"This area of research is important because warfarin is the most widely used oral anticoagulant, or blood thinner, worldwide," Limdi said. "Prescribing the drug is challenging because the dose, influenced by many factors, is difficult to predict and there can be serious bleeding when the dose is too high."

Previous studies on genetic regulation of warfarin have focused on the influence of two genes on warfarin dosing in a mostly white population.

"The population of African American patients at UAB provides an excellent opportunity to understand the role of these genes in this race group, which has previously been under-represented in studies. It also allows us to understand the differences in genetic influences by race group," Limdi said. "Probably the most important contribution of the investigators at UAB is the two-year follow-up of all patients. This allows us to observe bleeding complications and understand the influence of genes and environment and study the interaction between the two."

The new grant will allow Limdi to expand the effort to include 50 candidate genes including those involved in warfarin pharmacodynamics and pharmacokinetics, the vitamin K cycle and the clotting cascade based on their known or inferred role in warfarin response. The results of this study will provide further understanding of the genetic contributions of warfarin response in both European and African Americans. This knowledge will provide an evidence base for cost-effectiveness evaluation and future pre-prescription genotyping for accurate warfarin dosing and promotion of its use in qualifying patients.