Medical Journal of Malaysia

MJM, Vol 70 Supplement 1 September 2015

Effects of pharmacist managing Warfarin medication therapy adherence clinic in Kemaman Hospital

Nur Ainina BS, Nur Farhana YS, Siti Nur’ain MS

Pharmacy Department Kemaman Hospital, Terengganu


Introduction: Warfarin therapy needs close monitoring throughout frequent fine-tune dosing based on INR level. Thus, pharmacist’s involvement in Warfarin Medication Therapy Adherence Clinic (WMTAC) is essential in patient’s warfarin therapy care. The objective of the study is to assess the International Normalised Ratio (INR) control and incidence of warfarin’s adverse event in patients on WMTAC at Kemaman Hospital, Terengganu.

Method: This is a cross-sectional retrospective study where patients under WMTAC were identified since 2010 until recent and selected based on inclusion and exclusion criteria. The one-year INR control in patients on WMTAC was assessed by calculating time-in-therapeutic range (TTR) where higher TTR represent higher percentage days within therapeutic range. The incidence of warfarin’s adverse event was assessed based on the number of occurrence. Data was analysed using SPSSv.16 with p<0.05 was considered statistical significant.

Results: From 157 WMTAC patients, 66 patients are included in this study (median age 54.0 years, IqR 23.0) base on inclusion criteria. The TTR for 1-year period shows mean ± SD of 60.6 ± 19.1%. There is an increment in TTR for the second 6 months compared to the first 6 months period (mean ± SD of 62.8 ± 26.5% and 56.1 ± 22.3% respectively with p=0.086). In addition, the higher TTR was associated with the least number of missed dose for the second 6 months period, (p<0.05). For 1-year period, patients without missed dose tend to achieve TTR ³60% (p=0.04). Only 30.3% patients presented with the incidence of warfarin’s adverse events (minor, 28.8% and major bleeding, 1.5%).

Conclusion: On-going involvement of pharmacist in monitoring WMTAC patients may improve INR control and awareness on incidence of warfarin’s adverse events.

Keywords: International Normalised Ratio, medication therapy adherence clinic, time-in-therapeutic range, Warfarin.