Evaluation of Efficacy of Short Message Service (SMS) Reminders in Improving Adherence to Laboratory Monitoring in Patients on Anticoagulation with Vitamin K antagonists(VKA): A Randomized Controlled Trial

The aim of the study was to assess whether SMS reminders to patients on Vit K antagonists(VKA) improved adherence to INR testing as compared to clinic based follow up. The study was a parallel group randomized open label single center study carried out at a tertiary care hospital in North India from Oct 2018 to Nov 2019. The interventional arm received SMS in Hindi or English on two consecutive days prior to scheduled INR testing. Primary outcome was percentage of patients adhering to regular INR testing in two groups. Secondary outcomes included time in therapeutic range(TTR) for each patient and proportion of patients having TTR of more than 60% by percentage method. 111 patients were screened and 98 were randomized into two groups (49 each group). In the control group 13(26.5%) as compared to 32(78%) in the intervention group were adherent to regular INR testing, the result was statistically significant (p <1 × 10-5). In control group only 8(16.2%) patients had TTR of > 60% as compared to 24(48.9%) in interventional arm and the result was statistically significant (RR 1.96). In our study we found that regular SMS reminders to patients on Vit K antagonists result in better adherence to regular INR testing.

The online version contains supplementary material available at 10.1007/s12288-025-01995-z.