Abstract
Background and Aims
Ukraine’s HIV epidemic remains concentrated in opioid dependent people who inject drugs (PWID) where opioid agonist therapies (OAT) like methadone (MMT) and buprenorphine (BMT) maintenance treatments are the most cost‐effective HIV prevention strategy, but remain under‐scaled. This study aimed to measure the association between dose and type of OAT prescribed and treatment retention.
Design
Observational longitudinal cohort study.
Participants/Setting
Patients (n=15,290) prescribed OAT throughout Ukraine from 2004 through 2016.
Measurements
Data were analyzed using time‐event strategies to estimate cumulative treatment retention, defined as time to OAT discontinuation. Cumulative retention proportions at 1, 12 and 36 months were assessed for outcomes. Cox‐regression with log‐rank likelihood assessed independent predictors of treatment discontinuation.
Findings
The proportion prescribed high (MMT: >85mg; BMT: ≥16mg), medium (MMT: >40‐85mg; BMT: >6‐15mg), and low (MMT: ≤40mg; BMT: ≤6mg) dosages was 25%, 43% and 32%, respectively. Retention was significantly higher for BMT than MMT both at 12 (89% vs 75%) and 36 months (80% vs 56%). Though dosing levels for BMT did not influence retention, increasing dosages for MMT were significantly associated with higher retention rates at 1 (90%, 96%, 99%), 12 (59%, 78%, 91%) and 36 (34%, 59%, 79%) months, respectively. Independent predictors associated with 12‐month OAT discontinuation were medium (adjusted hazards ratio: aHR=2.23; 95%CL=1.95‐2.54) and low (aHR=4.96; 95%CL=4.37‐5.63) OAT dosage relative to high dosage, male sex (aHR=1.27; 95%CL=1.14‐1.41), MMT relative to BMT prescription (aHR=1.57; 95%CL=1.32‐1.87), and receiving OAT in general (aHR=1.22; 95%CL=1.02‐1.46) or tuberculosis (aHR=1.43; 95%CL=1.10‐1.85) hospitals, relative to specialty addiction treatment and AIDS Center settings. Lower dosages contributed more to dropout especially at 1 month (aHR 3.12; 95%CL=2.21‐4.41 and aHR 7.71; 95%CL=5.51‐10.79 for medium and low dosages, respectively). Younger age was significantly associated with OAT discontinuation only at 36 months (aHR=1.08; 95%CI=1.02‐1.15).
Conclusions
Higher dosages of opioid agonist therapies, especially for methadone maintenance treatment patients, appear to be associated with higher levels of treatment retention in Ukraine.