Anticoagulation with Warfarin: Roles of Adherence, Social Support and Illness Perception

This study was aimed to determine (1) the associations between adherence to warfarin, social support, perception of illness, and demographic factors on the quality of international normalized ratios (INRs); as well as (2) the relationship between the patients' scores in the Malaysian medication adherence scale (MALMAS) and their current INRs.

This cross-sectional survey was conducted from November 2017 to January 2018 at the warfarin clinic of Jerantut Hospital, Malaysia.

Some 58 participants were recruited, of whom 70.7% were diagnosed with atrial fibrillation (AF). Overall, 87.9% of the participants claimed adherence to their warfarin regimens. Patients with good-quality INR therapy were significantly older, had a higher median income and longer appointment durations. In terms of illness perception (IP), participants with good-quality INR therapyhad significantly lower scores in the identity, personal control, and consequence domains. Overall, the total scores for IP were significantly lower in the good-quality INR therapy. Meanwhile, the MALMAS scores were significantly lower in patients with sub-therapeutic current INR. However, there were no associations between warfarin adherence and perceived social support with current TTR.

Monitoring of demographic factors and IP's domains is vital since they were associated with quality of INR therapy. Meanwhile, the occurrence of sub-therapeutic current INR should raise suspicion of poor adherence in these patients. Overall, IP and MALMAS are useful tools that should be integrated into the patient care protocols.