The characteristics and clinical outcomes of atrial fibrillation patient in middle income country of Indonesia

Background Atrial fibrillation (AF) is an increasing health concern in Asia, but data from developing countries remain scarce. Although direct oral anticoagulants (DOACs) are now preferred globally, vitamin K antagonists (VKAs) remain the mainstay of stroke prevention in low- and middle-income countries, including Indonesia. This study evaluates the clinical outcomes of Indonesian AF patients with warfarin-based treatment. Methods The OPTIMA (Optimal target of INR for Indonesian) study is a multicenter, prospective cohort study involving 1,599 AF patients across 25 centers in Indonesia. Clinical characteristics, INR levels, and time in therapeutic range (TTR) were analyzed. The primary endpoints were stroke/systemic embolism (efficacy) and major bleeding (safety). Cox proportional hazards regression and Kaplan–Meier analysis assessed outcomes. Results The mean CHA 2 DS 2 -VASc score was 2.43. Anticoagulation quality was poor under the standard INR target of 2.0–3.0, with a mean time in therapeutic range (TTR) of only 30.1%. Patients with an average INR of 1.6–2.5 experienced lower rates of stroke and major bleeding. The incidence rates per 100 patient-years were 1.32 for stroke, 1.51 for major bleeding, and 3.15 for mortality. Stroke risk was highest in persistent/permanent AF, with younger, working-age individuals disproportionately affected. Conclusions Warfarin management at the standard INR target of 2.0–3.0 was associated with poor anticoagulation quality. Patients with average INR values of 1.6–2.5 experienced fewer adverse events, although this finding requires confirmation in prospective trials. Socioeconomic burden is substantial, as AF-related stroke disproportionately affects younger, working-age Indonesians.