Low awareness of risk mitigation prescribing in response to dual crises of COVID-19 and overdose deaths among people who use unregulated drugs in Vancouver, Canada.

BACKGROUND: When the novel coronavirus pandemic emerged in March 2020, many settings across Canada and the USA were already contending with an existing crisis of drug overdoses due to the toxic unregulated drug supply. In response, the Canadian province of British Columbia (BC) released innovative risk mitigation prescribing (RMP) guidelines for medical professionals to prescribe pharmaceutical alternatives to unregulated drugs in an effort to support the self-isolation of people who use unregulated drugs (PWUD) in preventing both SARS-CoV-2 virus infection and overdoses. We sought to assess the level of awareness of RMP and identify factors associated with this awareness among PWUD in Vancouver, BC. METHODS: Cross-sectional data were derived from participants enrolled in three community-recruited prospective cohort studies of PWUD in Vancouver, interviewed between July and November 2020. Multivariable logistic regression analysis was used to identify factors associated with awareness of RMP. RESULTS: Among 633 participants, 302 (47.7%) had heard of RMP. Of those 302 participants, 199 (65.9%) had never tried to access RMP services, ten (3.3%) made an unsuccessful attempt to access RMP, and 93 (30.8%) received RMP. In the multivariable analysis, participants who had awareness of RMP guidelines were more likely to self-identify as white (adjusted odds ratio [AOR] = 1.47; 95% confidence interval [CI]: 1.01, 2.13), to have completed secondary school education or higher (AOR = 1.67; 95% CI: 1.16, 2.39), to have used drugs at a supervised consumption or overdose prevention site in the past six months (AOR = 1.66; 95% CI: 1.10, 2.52), and to have received opioid agonist therapy as treatment for opioid use disorder in the past six months (AOR = 1.51; 95% CI: 1.02, 2.24). CONCLUSION: At least four months after the release of the guidelines, RMP was known to less than half of our study participants, warranting urgent educational efforts for PWUD, particularly among racialized groups and those who were not accessing other harm reduction services. Furthermore, the majority of participants who were aware of RMP guidelines had never tried to access the service, suggesting the need to improve perceived accessibility and knowledge of eligibility criteria.

Evaluating the intended and unintended consequences of opioid-prescribing interventions on primary care in British Columbia, Canada: protocol for a retrospective population-based cohort study.

INTRODUCTION: Between 2015 and 2018, there were over 40 000 opioid-related overdose events and 4551 deaths among residents in British Columbia (BC). During this time the province mobilised a variety of policy levers to encourage physicians to expand access to opioid agonist treatment and the College of Physicians and Surgeons of British Columbia (CPSBC) released a practice standard establishing legally enforceable minimum thresholds of professional behaviour in the hopes of curtailing overdose events. Our goal is to conduct a comprehensive investigation of the intended and unintended consequences of these policy changes. Specifically, we aim to understand the effects of these measures on physician prescribing behaviours, identify physician characteristics associated with uptake of the new measures, and measure the effects of the policy changes on patients' access to quality primary care. METHODS AND ANALYSIS: This is a population-level, retrospective cohort study of all BC primary care physicians who prescribed any opioid medication for opioid-use disorder or chronic non-cancer pain during the study period, and their patients. The study period is 1 January 2013-31 December 2018, with a 1-year wash-in period (1 January 2012-31 December 2012) to exclude patients who initiated long-term opioid treatment prior to our study period or whose pain type (ie, 'chronic non-cancer', 'acute', 'cancer or palliative', or 'other') cannot be confirmed. The project combines five administrative health datasets under the authority of the BC Ministry of Health, with the CPSBC's Physician Registry, BC Cancer Agency's Cancer Registry and Vital Statistics' Mortality data. We will create measures of prescribing concordance, access, continuity, and comprehensiveness to assess primary care delivery and quality at both the physician and patient level. We will use generalised estimating equations, interrupted time series, mixed effects models, and funnel plots to identify factors related to changes in prescribing and evaluate the impact of the changes to prescribing policies. Results will be reported using appropriate Enhancing the QUAlity and Transparency Of health Research guidelines (eg, STrengthening the Reporting of OBservational studies in Epidemiology). ETHICS AND DISSEMINATION: This study has been approved by McGill University's Institutional Review Board (#A11-M55-19A), and the University of British Columbia's Research Ethics Board (#H19-03537). We will disseminate results via a combination of open access peer-reviewed journal publications, conferences, lay summaries and OpEds.

Development and characteristics of the Provincial Overdose Cohort in British Columbia, Canada.

INTRODUCTION: British Columbia (BC), Canada declared a public health emergency in April 2016 for opioid overdose. Comprehensive data was needed to identify risk factors, inform interventions, and evaluate response actions. We describe the development of an overdose cohort, including linkage strategy, case definitions, and data governance model, and present the resulting characteristics, including data linkage yields and case overlap among data sources. METHODS: Overdose events from hospital admissions, physician visits, poison centre and ambulance calls, emergency department visits, and coroner's data were grouped into episodes if records were present in multiple sources. A minimum of five years of universal health care records (all prescription dispensations, fee-for-service physician billings, emergency department visits and hospitalizations) were appended for each individual. A 20% random sample of BC residents and a 1:5 matched case-control set were generated. Consultation and prioritization ensured analysts worked to address questions to directly inform public health actions. RESULTS: 10,456 individuals suffered 14,292 overdoses from January 1, 2015 to Nov 30, 2016. Only 28% of overdose events were found in more than one dataset with the unique contribution of cases highest from ambulance records (32%). Compared with fatal overdoses, non-fatal events more often involved females, younger individuals (20 to 29 years) and those 60 or older. In 78% of illegal drug deaths, there was no associated ambulance response. In the year prior to first recorded overdose, 60% of individuals had at least one ED visit, 31% at least one hospital admission, 80% at least one physician visit, and 87% had filled at least one prescription in a community pharmacy. CONCLUSION: While resource-intensive to establish, a linked cohort is useful for characterizing the full extent of the epidemic, defining sub-populations at risk, and patterns of contact with the health system. Overdose studies in other jurisdictions should consider the inclusion of multiple data sources.

Differences in experiences of barriers to STI testing between clients of the internet-based diagnostic testing service GetCheckedOnline.com and an STI clinic in Vancouver, Canada.

OBJECTIVES: Internet-based STI testing programmes may overcome barriers posed by in-clinic testing, though uptake could reflect social gradients. The role these services play in comparison to clinical testing services is unknown. We compared experiences of testing barriers between STI clinic clients to clients of GetCheckedOnline.com (GCO; where clients take a printed lab form to a lab). METHODS: Our 10-month cross-sectional study was conducted after GCO was promoted to STI clinic clients and men who have sex with men (MSM). Clinic and GCO clients completed an online survey assessing testing barriers and facilitators; responses were compared using bivariate analysis (level of significance P<0.01; significant results below). RESULTS: Compared with 321 clinic clients, the 73 GCO clients were more likely to be older (median 35 vs 30 years), MSM (45% vs 16%), be testing routinely (67% vs 39%), have delayed testing for any reason (76% vs 54%) and due to clinic distance (28% vs 9%), report delays due to wait times (50% vs 17%), embarrassment with testing (16% vs 6%), discomfort discussing sexual health where they usually go for testing (39% vs 22%), as well as discomfort discussing sexual history with (19% vs 5%) and fearing judgement from (30% vs 15%) any healthcare provider. GCO clients were less likely to have found clinic hours convenient (59% vs 77%) and clinic appointments easy to make (49% vs 66%), and more likely to report long wait times (50% vs 17%). We found no differences in technology skills/use. CONCLUSIONS: In this urban setting, an internet-based testing service effectively engaged individuals experiencing testing barriers, with few social gradients in uptake. While some testing barriers could be addressed through increasing access to clinical services, others require social and structural changes, highlighting the importance of internet-based STI testing services to increasing test uptake.

Outbreak of Vibrio parahaemolyticus Associated with Consumption of Raw Oysters in Canada, 2015.

There has been a steady increase in illness incidence of Vibrio parahaemolyticus (Vp). The majority of illnesses are associated with consumption of raw oysters. In the summer of 2015, Canada experienced the largest outbreak associated with the consumption of raw oysters harvested from British Columbia (BC) coastal waters. Case investigation of laboratory-confirmed cases was conducted to collect information on exposures and to assist traceback. Investigations at processors and oyster sampling were conducted. Eighty-two laboratory-confirmed cases of Vp infection were reported between January 1 and October 26, 2015. The majority of the cases were reported in BC, associated with consumption of raw BC oysters in restaurants. Sea surface temperatures were above the historical levels in 2015. This outbreak identified the need to improve surveillance and response to increases in human cases of Vp. This is of particular importance due to the potential for increasing water temperatures and the likelihood of additional outbreaks of Vibrio.

At-a-glance - Impact of drug overdose-related deaths on life expectancy at birth in British Columbia. / Aperçu - Impact des décès par surdose de drogue sur l'espérance de vie à la naissance en Colombie-Britannique.

We quantified the contributions of leading causes of death and drug overdose to changes in life expectancy at birth over time and inequalities by sex and socioeconomic status in British Columbia. From 2014 to 2016, life expectancy at birth declined by 0.38 years and drug overdose deaths (mainly opioid-involved) contributed a loss of 0.12 years of the decrease. The analysis also demonstrated that the higher drug overdose mortality among males and among those in lower socioeconomic status communities contributed to a differential decrease in life expectancy at birth for males and for those in the latter category.

RÉSUMÉ: Nous avons quantifié la contribution des principales causes de décès et de surdose à l'évolution de l'espérance de vie à la naissance et aux disparités en matière de sexe et de situation socioéconomique en Colombie-Britannique. Entre 2014 et 2016, l'espérance de vie à la naissance a diminué de 0,38 an et les décès par surdose (principalement liés aux opioïdes) ont contribué à ce recul pour 0,12 an. L'analyse a également montré que le taux plus élevé de mortalité par surdose constaté chez les hommes et les membres des catégories socioéconomiques plus défavorisées a contribué à une diminution différentielle dans ces deux groupes de l'espérance de vie à la naissance.

Distribution of take-home opioid antagonist kits during a synthetic opioid epidemic in British Columbia, Canada: a modelling study.

BACKGROUND: Illicit use of high-potency synthetic opioids has become a global issue over the past decade. This misuse is particularly pronounced in British Columbia, Canada, where a rapid increase in availability of fentanyl and other synthetic opioids in the local illicit drug supply during 2016 led to a substantial increase in overdoses and deaths. In response, distribution of take-home naloxone (THN) overdose prevention kits was scaled up (6·4-fold increase) throughout the province. The aim of this study was to estimate the impact of the THN programme in terms of the number of deaths averted over the study period. METHODS: We estimated the impact of THN kits on the ongoing epidemic among people who use illicit opioids in British Columbia and explored counterfactual scenarios for the provincial response. A Markov chain model was constructed explicitly including opioid-related deaths, fentanyl-related deaths, ambulance-attended overdoses, and uses of THN kits. The model was calibrated in a Bayesian framework incorporating population data between Jan 1, 2012, and Oct 31, 2016. FINDINGS: 22 499 ambulance-attended overdoses and 2121 illicit drug-related deaths (677 [32%] deaths related to fentanyl) were recorded in the study period, mostly since January, 2016. In the same period, 19 074 THN kits were distributed. We estimate that 298 deaths (95% credible interval [CrI] 91-474) were averted by the THN programme. Of these deaths, 226 (95% CrI 125-340) were averted in 2016, following a rapid scale-up in distribution of kits. We infer a rapid increase in fentanyl adulterant at the beginning of 2016, with an estimated 2·3 times (95% CrI 2·0-2·9) increase from 2015 to 2016. Counterfactual modelling indicated that an earlier scale-up of the programme would have averted an additional 118 deaths (95% CrI 64-207). Our model also indicated that the increase in deaths could parsimoniously be explained through a change in the fentanyl-related overdose rate alone. INTERPRETATION: The THN programme substantially reduced the number of overdose deaths during a period of rapid increase in the number of illicit drug overdoses due to fentanyl in British Columbia. However, earlier adoption and distribution of the THN intervention might have had an even greater impact on overdose deaths. Our findings show the value of a fast and effective response at the start of a synthetic opioid epidemic. We also believe that multiple interventions are needed to achieve an optimal impact. FUNDING: Canadian Institutes of Health Research Partnerships for Health Systems Improvement programme (grant 318068) and Natural Science and Engineering Research Council of Canada (grant 04611).

Near real-time monitoring of HIV transmission hotspots from routine HIV genotyping: an implementation case study.

BACKGROUND: HIV evolves rapidly and therefore infections with similar genetic sequences are likely linked by recent transmission events. Clusters of related infections can represent subpopulations with high rates of transmission. We describe the implementation of an automated near real-time system to monitor and characterise HIV transmission hotspots in British Columbia, Canada. METHODS: In this implementation case study, we applied a monitoring system to the British Columbia drug treatment database, which holds more than 32 000 anonymised HIV genotypes for nearly 9000 residents of British Columbia living with HIV. On average, five to six new HIV genotypes are deposited in the database every day, which triggers an automated reanalysis of the entire database. We extracted clusters of five or more individuals with short phylogenetic distances between their respective HIV sequences. The system generated monthly reports of the growth and characteristics of clusters that were distributed to public health officers. FINDINGS: In June, 2014, the monitoring system detected the expansion of a cluster by 11 new cases during 3 months, including eight cases with transmitted drug resistance. This cluster generally comprised young men who have sex with men. The subsequent report precipitated an enhanced public health follow-up to ensure linkage to care and treatment initiation in the affected subpopulation. Of the nine cases associated with this follow-up, all had already been linked to care and five cases had started treatment. Subsequent to the follow-up, three additional cases started treatment and most cases achieved suppressed viral loads. During the next 12 months, we detected 12 new cases in this cluster with reduction in the onward transmission of drug resistance. INTERPRETATION: Our findings show the first application of an automated phylogenetic system monitoring a clinical database to detect a recent HIV outbreak and support the ensuing public health response. By making secondary use of routinely collected HIV genotypes, this approach is cost-effective, attains near real-time monitoring of new cases, and can be implemented in all settings in which HIV genotyping is the standard of care. FUNDING: BC Centre for Excellence in HIV/AIDS, the Canadian Institutes for Health Research, the Genome Canada-CIHR Partnership in Genomics and Personalized Health, and the US National Institute on Drug Abuse.

Expansion of HAART coverage is associated with sustained decreases in HIV/AIDS morbidity, mortality and HIV transmission: the "HIV Treatment as Prevention" experience in a Canadian setting.

BACKGROUND: There has been renewed call for the global expansion of highly active antiretroviral therapy (HAART) under the framework of HIV treatment as prevention (TasP). However, population-level sustainability of this strategy has not been characterized. METHODS: We used population-level longitudinal data from province-wide registries including plasma viral load, CD4 count, drug resistance, HAART use, HIV diagnoses, AIDS incidence, and HIV-related mortality. We fitted two Poisson regression models over the study period, to relate estimated HIV incidence and the number of individuals on HAART and the percentage of virologically suppressed individuals. RESULTS: HAART coverage, median pre-HAART CD4 count, and HAART adherence increased over time and were associated with increasing virological suppression and decreasing drug resistance. AIDS incidence decreased from 6.9 to 1.4 per 100,000 population (80% decrease, p = 0.0330) and HIV-related mortality decreased from 6.5 to 1.3 per 100,000 population (80% decrease, p = 0.0115). New HIV diagnoses declined from 702 to 238 cases (66% decrease; p = 0.0004) with a consequent estimated decline in HIV incident cases from 632 to 368 cases per year (42% decrease; p = 0.0003). Finally, our models suggested that for each increase of 100 individuals on HAART, the estimated HIV incidence decreased 1.2% and for every 1% increase in the number of individuals suppressed on HAART, the estimated HIV incidence also decreased by 1%. CONCLUSIONS: Our results show that HAART expansion between 1996 and 2012 in BC was associated with a sustained and profound population-level decrease in morbidity, mortality and HIV transmission. Our findings support the long-term effectiveness and sustainability of HIV treatment as prevention within an adequately resourced environment with no financial barriers to diagnosis, medical care or antiretroviral drugs. The 2013 Consolidated World Health Organization Antiretroviral Therapy Guidelines offer a unique opportunity to further evaluate TasP in other settings, particularly within generalized epidemics, and resource-limited setting, as advocated by UNAIDS.

Pharmacy-based Immunization in Rural Communities Strategy (PhICS): A community cluster-randomized trial.

BACKGROUND: Influenza is a major cause of morbidity and mortality in Canada, with up to 7000 influenza-related deaths occurring every year. The elderly and individuals with chronic diseases are at increased risk for influenza-related morbidity and mortality. METHODS: We conducted a 2-year, community cluster-randomized trial targeting elderly people and at-risk groups to assess the effectiveness of pharmacy-based influenza vaccination clinics on influenza vaccination rates. Small rural communities in interior and northern British Columbia were randomly allocated to the intervention or control. In the intervention communities, pharmacy-based influenza vaccination clinics were held and were promoted to eligible patients using personalized invitations from the pharmacists, invitations distributed opportunistically by a pharmacist to eligible patients presenting to pharmacies during the flu season and community-wide promotion using posters and the local media. The main outcome measure was a difference in the mean influenza vaccination rates. The immunization rates were calculated using the number of immunizations given in each community divided by the population size estimated from the census data. RESULTS: Baseline influenza immunization rates in the population ≥65 years of age were the same in the control (n = 10, mean 85.6% [SD 16.6]) and intervention (n = 14, mean 83.8% [SD 16.3]) communities in 2009 (p = 0.79). In 2010, the mean influenza immunization rate was 56.9% (SD 28.0) in the control communities (n = 15) and 80.1% (SD 18.4) in the intervention communities (n = 14) (p = 0.01) for those ≥65 years of age. However, in 2010, for those 2 to 64 years with chronic medical conditions, the immunization rates were lower in the intervention communities (mean 16.3% [SD 7.1]) compared with the control communities (mean 21.2% [SD 5.8]) (p = 0.04). CONCLUSION: Clinics were feasible and well attended and they resulted in increased vaccination rates for elderly residents. In contrast, vaccination rates in the younger population with comorbidities remained low and unchanged.

Effectiveness of neuraminidase inhibitors in preventing hospitalization during the H1N1 influenza pandemic in British Columbia, Canada.

OBJECTIVES: In British Columbia (BC), Canada, neuraminidase inhibitors (NIs) were publicly funded during the 2009 A(H1N1)pdm09 pandemic for treatment of high-risk patients and/or anyone with moderate-to-severe illness. We assessed antiviral effectiveness (AVE) against hospitalization in that context. METHODS: A population-based cohort study was conducted using linked administrative data. The cohort included all individuals living in BC during the study period (1 September to 31 December 2009) with a diagnostic code consistent with influenza or pandemic H1N1. The main study period pertained to the second-wave A(H1N1)pdm09 circulation (1 October to 31 December 2009), with sensitivity analyses around the more specific pandemic peak (18 October to 7 November). Exposure was defined by same-day NI prescription. The main outcome was all-cause hospitalization within 14 days of the outpatient influenza diagnosis. Cox proportional hazards models assessed AVE with 1 : 1 propensity-score matching and covariate adjustment. RESULTS: After matching, there were 304/58,061 NI-exposed and 345/58,061 unexposed patients hospitalized during the main study period. The very young [<6 months (35.0; 95% CI 16.7-73.4)], the old [65-79 years (13.7; 95% CI 10.1-18.6)] and the very old [≥80 years (38.7; 95% CI 26.6-56.5)] had the highest hospitalization rate per 1000 patients overall. Fully adjusted AVE against all-cause hospitalization during the main study period was 16% (95% CI 2%-28%), similar to the pandemic peak (15%; 95% CI -4%-30%). CONCLUSIONS: The use of NIs was associated with modest protection against hospitalization during the 2009 pandemic, but appeared underutilized in affected age groups with the highest hospitalization risk.

Is there a need for heroin substitution treatment in Vancouver's Downtown Eastside? Yes there is, and in many other places too.

The prescription of medically-supervised diacetylmorphine, the active ingredient in heroin, to individuals with treatment-refractory opioid dependence is a controversial and often politically charged subject. Just as methadone maintenance was opposed in the 1960s by some treatment providers who preferred abstinence-based therapies, heroin-assisted therapy is now being opposed by some methadone treatment providers--this despite the fact that the effectiveness of heroin-assisted treatment has been demonstrated in no less than six randomized trials in Switzerland, the Netherlands, Spain, Germany, Canada and the UK. The North American Opiate Medication Initiative (NAOMI) trial in Canada clearly showed heroin-assisted therapy to be superior to methadone in individuals with chronic, treatment-refractory heroin addiction both in terms of retention in addiction treatment and clinical response. An international internal review panel, three Research Ethics Boards, the CIHR RCT review panel, the Therapeutic Products Directorate of Health Canada, and several journal peer-reviewers reviewed the NAOMI trial. Nevertheless, authors of a commentary in this issue of CJPH find fault with the trial in terms of methadone prescribing, use of intention-to-treat analysis, safety and cost. We take this opportunity to respond to the numerous misconceptions and errors in their commentary.