Anticoagulation therapy: patients attitude, knowledge, and concerns regarding their effects on the international normalized ratio (INR) in Saudi Arabia

Introduction: Thoughtful evaluation of patients’ knowledge, satisfaction, and concerns in Anticoagulation clinics will help to understand areas of improvement. Our study aimed to examine patients’ drug knowledge, satisfaction and concerns with provided anticoagulation services. Patients and Methods: We designed our study as a cross-sectional survey that was developed and conducted in a regional anticoagulation clinic with good number of patients. Two hundred sixty eight were recruited in the survey. Patients’ warfarin refill records and time within the therapeutic INR range were retrieved from hospital databases. Results: Adequate knowledge of warfarin-food and warfarin-drug interactions was lacking in about 50% of patients. Satisfaction with provided service was not optimal, Concerns associated with warfarin was bothersome to many patients due to possible drug-drug interactions (41.42%), missed doses impact (29.10%), adverse drug reactions (29.85%). All of which might lead to unfavorable consequences. Higher satisfaction was associated with better knowledge (r=0.27, p=0.001) and fewer concerns (rs=-0.26, p=0.002). Improved drug related knowledge and higher satisfaction were positively reflected in these patients’ attitude toward drug use compliance in knowledge (rs=0.23, p=0.01) and satisfaction (rs=0.19, p=0.041). Eventually, good INR control was shown more with better knowledge, higher satisfaction, and better warfarin adherence (p=0.004, 0.03, 0.04 and 0.004, respectively). Conclusion: There is a deficit in patients’ knowledge and satisfaction with warfarin therapy. Such deficits lifted the threshold of concerns with warfarin use and negatively affected INR control.