August 31st is International Overdose Awareness Day. This bonus edition of The Evidence Speaks features the secondary analyses of results from the Study to Assess Longer-Term Opioid Maintenance Effectiveness (SALOME), in which CHÉOS Scientists Drs. Eugenia Oviedo-Joekes, Michael Krausz, Aslam Anis, and Martin Schechter examine the study outcomes through the perspectives of gender, ethnicity, and safety.
Oviedo-Joekes E, Palis H, Guh D, Marchand K, Brissette S, Lock K, MacDonald S, Harrison S, Anis AH, Krausz M, Marsh DC, Schechter MT. Characteristics and response to treatment among Indigenous people receiving injectable diacetylmorphine or hydromorphone in a randomized controlled trial for the treatment of long-term opioid dependence. Drug Alcohol Rev. 2017 Jun 8 epub ahead of print.
This secondary analysis examined the baseline profile and the effectiveness of hydromorphone (HDM) and diacetylmorphine (DAM) for Indigenous participants in SALOME. One third of the participants identified as having Indigenous ancestry, compared to just 4 per cent in the general population.
The authors note that they chose to examine the results through this lens due to Indigenous people’s unique experiences of the health care system, drug use, and socioeconomic disadvantages, which are linked to their racial identity and the intergenerational trauma of Canada’s colonial past.
The analysis revealed that Indigenous people presented with more vulnerabilities at baseline: They had less education and higher rates of foster care and separation from biological parents compared to non-Indigenous participants. However, at the six-month mark of the study, they had reduced their use of street heroin, other opioids, and crack cocaine to a significantly greater extent than the non-Indigenous participants. Their illegal activity had also decreased. Retention in treatment was the same across the treatment arms.
The authors concluded that Indigenous people who are long-term opioid users and have not benefitted from first-line treatment are in need of second-line alternatives, such as hydromorphone or diacetylmorphine. Further, they noted the opportunity to expand the supervised model of care with injectable opioid substitutes to incorporate more “culturally safe approaches to treatment” that could serve Indigenous patients’ needs by honouring their history and culture.
Palis H, Marchand K, Guh D, Brissette S, Lock K, MacDonald S, Harrison S, Anis AH, Krausz M, Marsh DC, Schechter MT, Oviedo-Joekes E. Men’s and women’s response to treatment and perceptions of outcomes in a randomized controlled trial of injectable opioid assisted treatment for severe opioid use disorder. Subst Abuse Treat Prev Policy. 2017 May 19;12(1):25.
This secondary analysis sought to compare the experiences of male and female participants in SALOME. Prior studies had shown that women present to opioid assisted treatment with more structural vulnerabilities than men, including less education, and higher rates of infectious disease, suicide, crack cocaine use, sex work, mental distress, and histories of sexual abuse—which can put them at risk for negative outcomes. Thus, the authors noted the importance of determining whether the treatments tested in SALOME, a trial whose participants already represented the most vulnerable of long-term street opioid users, can engage and retain women as well as men.
The authors examined treatment outcomes for both genders by comparing their different baseline characteristics, and the outcomes six months into the trial (any changes in illicit heroin use, opioid use, crack cocaine use, non-legal activities, physical and psychological health scores, urine positive for street heroin markers, and retention). They also investigated the participants’ perceptions of treatment effectiveness using a thematic analysis of their responses to open-ended interview questions regarding the outcomes of the treatment.
The researchers found that, at baseline, the men and women reported similar habits of heroin and opioid use in one prior month. However, women in the study tended to be younger, and reported more sex work, crack cocaine use, almost double the rates of HIV, and an overall poorer health than the men. Additionally, a higher proportion of women identified as Indigenous.
At the 6-month evaluation point, no significant differences in outcomes such as days of illicit heroin and opioid use were found between men and women. However, although both men and women presented similar physical health at 6 months, women’s psychosocial health was significantly improved compared to the men’s.
Moreover, 91.62 per cent of the effectiveness survey’s respondents said the treatment they were receiving was effective, while 5.23 per cent said it was not and 3.14 per cent were unsure. The most commonly cited reasons for effectiveness included improved health, improved quality of life, and reduced or halted street drug use, with a similar proportion of men and women referencing these themes.
The authors found their responses particularly interesting because a prior analysis of results from North American Opiate Medication Initiative (NAOMI), a clinical trial by CHÉOS Scientists investigating diacetylmorphine effectiveness, had shown that many trial participants were drawn to the treatment primarily because of the possibility of receiving pharmaceutical grade heroin. However, there was not a strong emphasis on the medication itself when men and women in SALOME were asked why the treatment was effective for them. Instead, they spoke of improvements in various aspects of life, including improved interpersonal relationships, health, and quality of life—areas the patients said they were able to focus on once their physical dependence was addressed.
The authors noted that the high retention rate (83 per cent) for women, similar to that for men (79 per cent), presents a compelling case for the treatment because of its potential to engage women with other services and care.
Oviedo-Joekes E, Brissette S, MacDonald S, Guh D, Marchand K, Jutha S, Harrison S, Janmohamed A, Zhang DZ, Anis AH, Krausz M, Marsh DC, Schechter MT. Safety profile of injectable hydromorphone and diacetylmorphine for long-term severe opioid use disorder. Drug Alcohol Depend. 2017 Jul 1;176:55-62.
In this secondary analysis, the researchers investigated whether adverse events during treatment were associated with daily-total dose or the patients’ attendance to the clinic. The most common adverse events were post-injection reactions, such as overdose, injection site skin irritation, and drowsiness.
An adjusted analysis showed that patients receiving hydromorphone were significantly less likely to experience adverse effects compared to patients on diacetylmorphine. However, for both groups, experiencing adverse events did not appear to be directly or solely linked to the average daily-dose, nor did it lead patients to miss more treatment days than patients who had not experienced side effects.
The authors noted that adverse events can be safely mitigated and treated by health care staff in the supervised model of care, as was the case throughout the SALOME trial. They reasoned that, although previous research has shown oral methadone to be safer than injectable diacetylmorphine, the approximately 80 per cent retention rate in SALOME—a treatment model where side effects can be managed by health care staff and patients can engage with additional services—presents an advantage over other forms of treatment where fewer patients are retained and instead face greater risks of street opioid injection and related harm.