Unintended impacts of regulatory changes to British Columbia Methadone Maintenance Program on addiction and HIV-related outcomes: An interrupted time series analysis

Abstract

Background In February 2014, several regulatory reforms were introduced to the methadone maintenance treatment (MMT) program in British Columbia, Canada, including a switch to a ten-times more concentrated methadone formulation and restrictions in pharmacy delivery services. We evaluated possible unintended effects of these changes on illicit drug use patterns and HIV treatment outcomes among HIV-positive opioid users. Methods Data was drawn from ACCESS, a prospective community-recruited cohort of HIV-positive people who use illicit drugs in Vancouver, Canada. Interrupted time series analyses were used to evaluate impacts of the policy change on monthly rates of MMT enrollment, illicit heroin injection, antiretroviral therapy (ART) adherence, and HIV viral suppression among HIV-positive opioid users between November 2012 and May 2015. Results A total of 331 HIV-positive opioid users were included. The MMT policy change led to a significant immediate 11.5% increase in heroin injection, and 15.9% drop in optimal ART adherence. A gradual increase in the prevalence of MMT enrolment after the policy change was also documented (0.9% per month). No changes in viral suppression rates were observed. Conclusions We observed immediate increases in illicit heroin injection and decreases in ART adherence in the wake of regulatory changes to the local MMT program. These findings underscore the need to consider potential unintended effects of altering health programmes for vulnerable populations, the need to develop appropriate mitigation strategies, as well as to involve all relevant stakeholders in the planning and implementations of new policies.

Trends in engagement in the cascade of care for opioid use disorder, Vancouver, Canada, 2006–2016

“…While this is encouraging, it should be noted that after a steady increase in the proportion of participants meeting each of the cascade stages between 2006 and 2014, we observed a declining trend in the last two years of the study period. This worsening of cascade indicators occurred after regulatory changes to the BC OAT program in February 2014, and are consistent with prior research (McNeil et al, 2015; Socias et al, 2017). Specifically, both quantitative and qualitative studies demonstrated interruptions in OAT and co-dispensed medications (e.g., antiretroviral therapy) following restrictions on pharmacy delivery services, as well as increases in injection opioid use, which might be explained by “change intolerance” to the new methadone formulation experienced by some OAT clients (McNeil et al, 2015; Socias et al, 2017).…”

“…This worsening of cascade indicators occurred after regulatory changes to the BC OAT program in February 2014, and are consistent with prior research (McNeil et al, 2015; Socias et al, 2017). Specifically, both quantitative and qualitative studies demonstrated interruptions in OAT and co-dispensed medications (e.g., antiretroviral therapy) following restrictions on pharmacy delivery services, as well as increases in injection opioid use, which might be explained by “change intolerance” to the new methadone formulation experienced by some OAT clients (McNeil et al, 2015; Socias et al, 2017). Importantly, had a quality improvement framework (e.g., cascade of care) been in place (Clarke et al, 2016), it may have facilitated early identification of the worsening of cascade indicators, interventions to prevent attrition, and potentially averted some of the overdose deaths observed during this period.…”

“…During the study period, injectable OAT (i.e., diacetylmorphine and hydromorphone) was only available in research settings. In February 2014, a number of regulatory changes were introduced to BC’s OAT program, including a change in the methadone formulation, and restrictions in pharmacy delivery services, which resulted in a number of concerns among OAT clients (McNeil et al, 2015; Socias et al, 2017).…”

The relationship between opioid agonist therapy satisfaction and fentanyl exposure in a Canadian setting

“…Another potential significant contributor to dissatisfaction is the regulatory change in British Columbia introduced in 2014 to the Methadone Maintenance Program, which involved changing the methadone formulation [26]. Previous studies reported significant increases in the prevalence of heroin injection and opioid withdrawal symptoms following this regulatory change in our setting [27,28].…”

Trajectories of injection drug use among people who use drugs in Vancouver, Canada, 1996–2017: growth mixture modeling using data from prospective cohort studies

“…Another recently published study assessed patterns of changes in injecting frequency in a European population and found similar longitudinal patterns , but the overall decreasing trend was not as strong as in the ALIVE cohort. In the face of escalating harmful illicit drug use, harm‐reduction interventions, including needle and syringe programs , supervised consumption facilities and methadone maintenance therapy , have been implemented and scaled‐up in British Columbia, Canada. However, to our knowledge, there exist no studies that have examined the longitudinal trajectories of injection drug use in a Canadian setting.…”