Clinical outcomes of telepharmacy services for outpatients receiving warfarin during the COVID-19 pandemic at Maharaj Nakorn Chiang Mai Hospital
Keywords:
postal delivery, COVID-19, telepharmacy services, warfarin, INR, adverse drug reactionsAbstract
Introduction: The development of a postal medication delivery system and telepharmacy services in patients receiving warfarin during the COVID-19 pandemic at Maharaj Nakorn Chiang Mai Hospital lacked operational outcome data.
Objective: To evaluate the impact of telepharmacy services on International Normalized Ratio (INR) control within therapeutic ranges and adverse drug reactions (ADRs) among warfarin-treated outpatients, and to identify factors associated with achieving target INR levels in patients receiving warfarin through postal delivery services.
Study Method: This retrospective study examined outpatients enrolled in a postal warfarin delivery program from January 1, 2021 to July 31, 2021 at Maharaj Nakorn Chiang Mai Hospital. Pharmacists conducted telephone follow-up calls to monitor medication adherence. Data were analyzed using descriptive statistics and logistic regression analysis.
Results: Among 149 patients, the prevalence of therapeutic INR before and after postal warfarin delivery was 52.3% and 45%, respectively. Forty-four patients (29.5%) maintained therapeutic INR levels continuously both before and after completion of the postal warfarin delivery program. Minor bleeding events occurred in 8 patients (5.4%). Factors significantly associated with achieving target INR levels included diabetes mellitus (aOR: 0.16, 95% CI: 0.05-0.57, p = 0.005) and therapeutic INR level prior to postal delivery (aOR: 3.00, 95% CI: 1.38-6.58, p = 0.006).
Conclusions: The prevalence of therapeutic INR levels among patients receiving telepharmacy services was relatively low. For optimal outcomes in postal warfarin delivery programs, patients should achieve therapeutic INR control before program initiation and have no history of diabetes mellitus.
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