RESUMO
CONTEXT: Immigrants from the former Union of Soviet Socialist Republics (USSR) are more prevalent in Methadone maintenance treatment (MMT) in Israel than their percentage in the general population. AIMS: To compare their characteristics and outcomes to those of Israeli-born and other immigrant patients. METHODS: Retention and survival since admission (June/1993-Dec/2022) until leaving treatment (for retention), or at the end of follow-up were analyzed. Vital data was taken from a national registry. Predictors were estimated using Kaplan-Meier and Cox regression models. RESULTS: The USSR patients (N = 262) compared with other immigrants (N = 132) and Israeli-born (N = 696) were more educated (≥ 12y) (p < 0.001), admitted to MMT at a younger age (p < 0.001), following a shorter duration of opioid usage (p < 0.001). More of them ever injected drugs (p < 0.001) and ever drank alcohol (p < 0.001). One-year retention was comparable (77.2% vs. 75.6% and 72%, p = 0.2) as did opioid discontinuation in those who stayed (p = 0.2). Former USSR patients had longer cumulative retention of their first admission (p = 0.05) with comparable overall retention since first admission, and survival, although the age of death was younger. Specific origin within the former USSR found immigrants from the Russian Federation with the best outcome, and those from Ukraine as having high HIV seropositive and shorter retention. CONCLUSIONS: Despite several characteristics known to be associated with poor outcomes, former USSR immigrants showed better adherence to MMT, reflected by their longer cumulative retention in their first admission, lower rate of readmissions, and a comparable survival and overall retention in treatment. An in depth study is needed in order to understand why they decease at a younger age.