RESUMEN
BACKGROUND: Kabul has over 12,000 people who inject drugs (PWID), most of them heroin users, and opioid substitution therapy has recently been introduced as an effective method to reduce opioid use. We aimed to evaluate a pilot Opioid Substitution Therapy Pilot Program (OSTPP) in Kabul, Afghanistan, particularly to (1) describe characteristics of the participants enrolled in the program and (2) identify factors associated with client retention in the OSTPP. FINDINGS: Two cross-sectional surveys evaluated participants attending the OSTPP at baseline (n = 83) and 18 months after (n = 57). Questionnaires assessed socio-demographic, drug use behavior, and general and mental health factors. After 18 months, 57 participants remained in the OSTPP. Participants lost to follow-up were younger (p < 0.01) and married (p < 0.01) and had no family contact (p < 0.01). Participants at 18 months reported no criminal activity in the last month and only two (3.5 %) reported heroin use in the last month, constituting significant decreases from baseline. CONCLUSIONS: While preliminary results are promising, further evaluation is needed to determine the feasibility of implementing OSTPP in this setting and effectiveness in reducing injection risk behaviors in Afghanistan.