A Case Control Study of Nutrient Intake Deficiencies in Patients Taking Warfarin

Abstract

Introduction We previously published the case of a woman taking warfarin who was found to have scurvy, a disease caused by a deficiency of vitamin C. This led us to hypothesize that patients taking warfarin who consume a diet limited in vitamin K rich foods may be at risk for other nutrient deficiencies. To test our hypothesis, we studied dietary nutrient intake in patients taking warfarin compared to patients with heart disease not taking warfarin. Methods The warfarin (n=59) and control groups (n=24) comprised convenience samples of patients with heart disease over age 60 years. Patients completed a three-day food diary and reported use of supplements. Results Based on diet history, the most common deficiencies were vitamin D (100% both groups), vitamin E (93% warfarin, 92% control), vitamin A (71% warfarin, 71% control), vitamin K (66% warfarin, 58% control), vitamin C (58 % warfarin, 46% control) and pantothenic acid (69% warfarin, 71% control) with no significant differences in intake deficiencies between warfarin and control groups. Conclusion All of our patients had nutritional intake deficiencies. This may be due to Appalachian dietary habits and not the low vitamin K diet. It seems prudent to recommend multivitamins, however, universal multivitamin supplementation has not been supported by randomized controlled trials. More study is needed to determine the reason for poor nutritional intake in our Appalachian population and to determine whether similar results are evident in a larger sample.

Keywords

• nutrient
• deficiency
• vitamin
• Appalachian
• diet
• warfarin