HIV/AIDS masih menjadi masalah kesehatan global. Cakupan pengobatan ARV di Indonesia baru mencapai 70%, di bawah target UNAIDS 95%, sehingga berpotensi meningkatkan loss to follow up (LTFU). Papua Tengah memiliki angka LTFU tertinggi (67%) dan Kepulauan Bangka Belitung terendah (20%). Penelitian ini bertujuan untuk menganalisis determinan loss to follow up pengobatan ARV pada orang ODHIV di Provinsi Papua Tengah dan Kepulauan Bangka Belitung tahun 2025. Penelitian menggunakan desain cross-sectional. Analisis data dilakukan menggunakan regresi logistik multivariat dengan pelaporan adjusted odds ratio (AOR) dan interval kepercayaan 95%. Di Papua Tengah, LTFU berhubungan dengan usia > 30 tahun (AOR = 0,648; 95% CI: 0,523-0,803), tempat tinggal luar wilayah Papua Tengah (AOR = 0,357; 95% CI: 0,216-0,589), kelompok populasi kunci (AOR = 0,421; 95% CI: 0,261-0,679) dan inisiasi pengobatan ARV > 7 hari (AOR = 0,694; 95% CI: 0,564-0,854). Di Kepulauan Bangka Belitung, LTFU berhubungan dengan asal rujukan pada ODHIV datang sendiri (AOR = 0,687; 95% CI; 0,490-0,964), kelompok populasi kunci (AOR = 0,588; CI: 0,406-0,852) dan inisiasi pengobatann ARV > 7 hari (AOR = 0,687; CI: 0,488-0,969) dan terdapat interaksi antara jenis kelamin pada kelompok populasi (AOR = 3,621; 95% CI: 1,670-7,852; p = 0,001). Penelitian ini menunjukkan bahwa determinan LTFU pengobatan ARV bersifat kontekstual. Pada LTFU tinggi dipengaruhi oleh tempat tinggal di luar wilayah Papua Tengah, sedangkan LTFU rendah dipengaruhi oleh perempuan pada populasi umum.

HIV/AIDS remains a global health problem, including in Indonesia. ARV treatment is the only primary therapy to maintain the health of people living with HIV. However, ARV treatment coverage in Indonesia is still relatively low at 70%, lower than the UNAIDS target of 95%, potentially increasing the incidence of loss to follow-up (LTFU). Central Papua has the highest LTFU rate (67%), while the Bangka Belitung Islands have the lowest rate (20%) in Indonesia. This study aims to analyze the determinants of loss to follow-up on ARV treatment in people living with HIV in Central Papua Province and the Bangka Belitung Islands in 2025. The study used a cross-sectional design. Data analysis was performed using multivariate logistic regression with reporting adjusted odds ratios (AOR) and 95% confidence intervals. In Central Papua, high LTFU was significantly associated with age > 30 years (AOR = 0.648; 95% CI: 0.523-0.803), residence outside Central Papua (AOR = 0.357; 95% CI: 0.216-0.589), key population groups (AOR = 0.421; 95% CI: 0.261-0.679) and initiation of ARV treatment > 7 days (AOR = 0.694; 95% CI: 0.564-0.854). In the Bangka Belitung Islands, LTFU was associated with the origin of referral in PLHIV coming alone (AOR = 0.687; 95% CI; 0.490-0.964), key population groups (AOR = 0.588; CI: 0.406-0.852) and ARV treatment initiation > 7 days (AOR = 0.687; CI: 0.488-0.969) and there was an interaction between gender in population groups (AOR = 3.621; 95% CI: 1.670-7.852; p = 0.001). This study demonstrated that the determinants of long-term survival (LTFU) on ARV treatment are contextual. High LTFU was influenced by residence outside of Central Papua, while low LTFU was influenced by female status in the general population.