"The findings revealed that exposures to MOUD, even if not continued throughout the six-month exposure period was associated with reduced risk of a fatal poisoning compared to non-MOUD forms of treatment and no treatment exposure. It is also clear that risk of death associated with exposure to non-MOUD forms of treatment was no less than that for no treatment; indeed, non-MOUD treatment might have produced worse outcomes than no treatment. Comparing the relative risk for the treatments for which agency-based numbers are available revealed that any exposure to methadone in the six months prior to death in 2017 was associated with 65% reduced relative risk of fatal opioid poisoning compared to exposure to any non-MOUD treatment recorded in the DMHAS database. Even more apparent, based on the available data from 2017, the relative risk of fatal opioid death in the six months following exposure to non-MOUD treatments ranged from 1.5 to 1.74 compared to no treatment. This is an unacceptably high probability for treatments that are purported to benefit patients with OUD and likely to be paid for by public tax revenues. In fact, it seems likely, based on our estimates of the number of people with OUD not exposed to treatment, that non-MOUD treatments were inferior to no treatment.

"There is a century of data demonstrating that non-MOUD treatment is followed by a high rate of relapse to opioid use – especially for morphine and heroin – approaching 90% at six months (Musto, 1999, Broers et al., 2000, Heimer et al., 2019). Relapse rates for those regularly using fentanyl may be even higher (Stone et al. 2018). There is ample evidence from the U.S. and elsewhere that longer-term non-MOUD treatments place those who relapse at an especially high risk of opioid overdose and death.(Strang, Beswick and Gossop, 2003; Wakeman et al. 2020). There is also compelling evidence that agonist MOUD decreases opioid-involved and all-cause mortality (Santo et al. 2021), and nearly thirty years of evidence that methadone reduces HIV-related mortality (Fugelstad et al., 1995, Parashar et al., 2016, Sordo et al., 2017). Our analysis was based on exposures to treatment, not their completion or retention, therefore our findings indicate that exposures to agonist MOUD treatment convey more benefit that non-MOUD even if the treatment is incompletely adhered to or terminated."


Robert Heimer, Anne C. Black, Hsiuju Lin, Lauretta E. Grau, David A. Fiellin, Benjamin A. Howell, Kathryn Hawk, Gail D’Onofrio, William C. Becker, Receipt of Opioid Use Disorder Treatments Prior to Fatal Overdoses and Comparison to No Treatment in Connecticut, 2016-17, Drug and Alcohol Dependence, 2023, 111040, ISSN 0376-8716, doi.org/10.1016/j.drugalcdep.2023.111040.