The impact of proposed price regulations on new patented medicine launches in Canada: a retrospective cohort study.

BACKGROUND: The Patented Medicine Prices Review Board (PMPRB), the agency that regulates the prices of patented medicines in Canada, published proposed amendments to the regulatory framework in December 2017. Because of a series of changes and delays, the revised policy has not yet been finalized. We sought to evaluate the potential early impact of the uncertainty about the PMPRB policy on patented-medicine launches. METHODS: We developed a retrospective cohort of patented medicines (molecules) sold in Canada and the 13 countries that the PMPRB currently uses or has proposed to use as price comparators, from sales data from the IQVIA MIDAS database for 2012-2021. The outcome was whether a molecule was launched (i.e., sold) in a specific country within 2 years of its global first launch (2-yr launch). We compared the change of 2-year launch before (2012-2017) and after the proposed amendments were published ("uncertain period," 2018-2021) in Canada with the change in the United States and the other 12 countries as a group ("other-countries group"), using interrupted time series and logistic regressions, respectively. We further conducted analyses for each individual country and subgroups by molecule characteristics, such as therapeutic benefit, separately. RESULTS: We included 242 and 107 new molecules launched before publication of the proposed amendments and during the uncertain period, respectively. The corresponding 2-year launch proportions were 45.0% and 30.8% in Canada, 81.4% and 82.2% in the US, and 83.9% and 70.1% in the other-countries group. All analyses showed changes in 2-year launch during the uncertain period in the US and in the other-countries group that were similar to the changes in Canada. Greater decreases were observed in Norway and Sweden than in Canada. The 2-year launch proportion for molecules with major therapeutic benefit decreased from 45.8% to 31.3% in Canada during the uncertain period and from 87.5% to 62.5% in the other-countries group, but increased from 91.7% to 100% in the US. INTERPRETATION: No negative impact of the PMPRB-policy uncertainty on molecule launches was observed when comparing Canada with price-comparator countries, except for molecules with major therapeutic benefit. The reduction in launches of medicines with major therapeutic benefit in Canada requires continuing investigation.

Quality of life of the Canadian population using the VR-12: population norms for health utility values, summary component scores and domain scores.

OBJECTIVES: To estimate Canadian population norms (health utility values, summary component scores and domain scores) for the VR-12. METHODS: English and French speaking Canadians aged 18 and older completed an online survey that included sociodemographic questions and standardized health status instruments, including the VR-12. Responses to the VR-12 were summarized as: (i) a health utility value; (ii) mental and physical component summary scores (MCS and PCS, respectively), and (iii) eight domain scores. Norms were calculated for the full sample and by gender, age group, and province/territory (univariate), and for several multivariate stratifications (e.g., age group and gender). Results were summarized using descriptive statistics, including number of respondents, mean and standard deviation (SD), median and percentiles (25th and 75th), and minimum and maximum. RESULTS: A total of 6761 people who clicked on the survey link completed the survey (83.4% completion rate), of whom 6741 (99.7%) were included in the analysis. The mean health utility score was 0.698 (SD = 0.216). Mean health utility scores tended to be higher in older age groups, ranging from 0.661 (SD = 0.214) in those aged 18-29 to 0.728 (SD = 0.310) in those aged 80+. Average MCS scores were higher in older age groups, while PCS scores were lower. Females consistently reported lower mean health utility values, summary component scores and domain scores compared with males. CONCLUSIONS: This is the first study to present Canadian norms for the VR-12. Health utility norms can serve as a valuable input for Canadian economic models, while summary component and domain norms can help interpret routinely-collected data.

Do Biologic Therapies for Rheumatoid Arthritis Offset Treatment-Related Resource Utilization and Cost? A Review of the Literature and an Instrumental Variable Analysis.

PURPOSE OF REVIEW: One justification for using expensive biologic therapy in rheumatoid arthritis (RA) has been that it can reduce future healthcare utilization such as joint surgeries and physician visits. However, the evidence to support this assertion is unclear. We conducted a review of the literature for studies which have analyzed the trends in resource use of RA patients, and then undertook a retrospective observational analysis of a Canadian administrative database using instrumental variable methods. RECENT FINDINGS: Our review found a trend in reduced resource utilization prior to the introduction of biologics and no evidence that biologic therapies have specifically contributed to this reduction. Our observational analysis, which overcame some of the epidemiological challenges with determining the influence of biologics on resource utilization, found a possible reduction in other medications but possible increases rather than decreases in physician visits and hospitalizations. However, our sample was not sufficiently large to make definitive conclusions. Over 15 years since the introduction of biologics for RA, no evidence exists supporting the assumption that biologic therapies reduce future healthcare utilization. While such a question is challenging to generate evidence for, and so an absence of evidence does not suggest that the hypothesis is incorrect, an instrumental variable analysis using sufficient data could provide definitive evidence.

Access criteria for anti-TNF agents in spondyloarthritis: influence on comparative 1-year cost-effectiveness estimates.

BACKGROUND: Anti-tumor necrosis factor (anti-TNF) agents are an effective, but costly, treatment for spondyloarthritis (SpA). Worldwide, multiple sets of access criteria aim to restrict anti-TNF therapy to patients with specific clinical characteristics, yet the influence of access criteria on anti-TNF cost-effectiveness is unknown. Our objective was to use data from the DESIR cohort, a prospective study of early SpA patients in France, to determine whether the French anti-TNF access criteria are the most cost-effective in that setting relative to other potential restrictions. METHODS: We used data from the DESIR cohort to create five study populations of patients meeting anti-TNF access criteria from Canada, France, Germany, United Kingdom, and Hong Kong, respectively. For each study population, we calculated the costs and quality-adjusted life years (QALYs) over 1 year of patients treated and not treated with anti-TNF therapy. To control for differences between anti-TNF users and non-users, we used linear regression models to derive adjusted mean costs and QALYs. We calculated incremental cost-effectiveness ratios (ICERs) representing the incremental cost per additional QALY gained by treating with an anti-TNF within each of the five study populations, using bootstrapping to explore the range of uncertainty in costs and QALYs. A series of sensitivity analyses was conducted, including one to simulate the effect of a 24-week stopping rule for anti-TNF non-responders. RESULTS: Anti-TNF access criteria from France were satisfied by the largest proportion of DESIR patients (27.8%), followed by Germany (25.1%), Canada (23.8%), the UK (12.1%) and Hong Kong (8.6%). Confidence intervals around incremental costs and QALYs in the basecase analysis were overlapping, indicating that anti-TNF cost-effectiveness estimates derived from each subset were similar. In the sensitivity analysis that examined the effect of excluding costs accumulated past 24 weeks by anti-TNF non-responders, the incremental cost per QALY was reduced by approximately 25% relative to the basecase analysis (France: €857,992 vs. €1,105,859; Canada: € 626,459 vs. €818,186; Germany: € 422,568 vs. €545,808); UK €578,899 vs. €766,217; Hong Kong €335,418 vs. €456,850). CONCLUSIONS: Anti-TNF cost-effectiveness is strongly affected by treatment continuation among non-responders. Access criteria could improve anti-TNF cost-effectiveness by defining patients likely to respond.

The Impact of Price-cap Regulations on Exit by Generic Pharmaceutical Firms.

BACKGROUND: In 1998, the Province of Ontario in Canada adopted price-cap "70/90" regulations whereby the first generic entrant was required to be priced at ≤70% of the associated brand-name product and subsequent generics were priced at ≤90% of the first generic price. The price-caps were further lowered to 50% in 2006 and 25% in 2010. This study assessed the impact of such price-cap regulations on exit by generic drug firms. METHODS: Formulary (2003-2012) listings of prescription drugs covered under the Ontario Drug Benefit program were used. The formulary tracks the "status" (on formulary, discontinued by manufacturer, and delisted for other reasons) for each drug. Markets were defined based on unique active ingredient and form within Ontario. Firm exit occurred when a manufacturer discontinued all its generic drugs within a market. The exit rate was defined as the number of generic firm-market exits divided by total generic firm-market follow-up years. Poisson regression was used to compare the exit rates during the 3 policy periods ("25," "50," and "70/90"). RESULTS: A total of 1126 generic manufacturers paired with 290 markets were identified. The exit rate ratio during the 25% price-cap period compared with the 70%/90% period was 2.42 (95% confidence interval, 1.56-3.77). A small manufacturer or a manufacturer in a market with ≥3 competitors or in an older market was more likely to exit. CONCLUSIONS: Lowering the price-cap level is associated with a higher incidence of generic firm exit from markets. Continuously reducing price-caps may have the unintended consequence of forcing generic firms to exit.

Long-term (10-year) mortality of younger previously healthy patients with severe sepsis/septic shock is worse than that of patients with nonseptic critical illness and of the general population.

OBJECTIVES: Long-term (1- to 10-year) outcomes after severe sepsis in previously healthy persons are unknown. We aimed to determine the 1- to 10-year mortality rates of previously healthy patients with severe sepsis and compare these to mortality rates of patients with nonseptic critical illness and the general population. DESIGN: A prospective cohort study of 2,289 patients from one mixed medical-surgical ICU and one cardiovascular surgery ICU. Age- and gender-comparable general British Columbia population was used as comparison. Patients were followed from the date of admission to the ICU to January 31, 2013. Provincial vital statistics were used to determine the patients' date of death. For the general population comparison, expected survival was obtained from life tables of the population of British Columbia, Canada. SETTING: A quaternary-level provincial referral hospital in Vancouver, British Columbia, Canada. PATIENTS: Two thousand two hundred eighty-nine patients from one mixed medical-surgical ICU and one cardiovascular surgery ICU. Age- and gender-comparable general British Columbia population was used for comparison. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients with severe sepsis without comorbidities had higher mortality from 1 to 10 years than general British Columbia population (p < 0.01). Younger patients with severe sepsis (< 60 yr) had the worst 1- to 5-year and 5- to 10-year mortality (hazard ratio [95% CI], 17.8 [13.4-24.8] and 6.0 [4-9]) compared with the general population. Patients with severe sepsis had significantly poorer 1- to 10-year mortality rates (30.5%) compared with patients with nonseptic critical illness (22.1%) and patients who have undergone cardiovascular surgery (15.9%). Patients with sepsis had higher mortality rates from 1-5 years and 5-10 years than the general British Columbia population (hazard ratio [95% CI], 4.5 [2.2-9.1] and 2.2 [0.9-14.7]). CONCLUSIONS: Previously healthy patients suffering an episode of severe sepsis have increased long-term mortality compared with patients with nonseptic critical illness and a general population.

The Association of Rheumatologist Supply and Multidisciplinary Care With Timely Patient Access to Rheumatologists: Evidence From British Columbia, Canada.

OBJECTIVE: The objective was to understand how the expansion of rheumatology supply and the introduction of multidisciplinary care was associated with access to rheumatology services. METHODS: We accessed Population Data BC, a longitudinal database with de-identified individual-level health data on all residents of British Columbia, Canada, to analyze physician visits and prescribing from 2010-2011 to 2019-2020. We calculated access as the time from referral to first rheumatologist visit and, for people with rheumatoid arthritis (RA), time to first disease-modifying antirheumatic drug (DMARD). Associations between lag time, patient characteristics, and system variables were explored using quantile regression. RESULTS: Over the study period, there were 149,902 new rheumatologist visits, with 31% more visits in 2019-2020 than in 2010-2011. The proportion of first visits for patients with inflammatory arthritis increased from 28% to 51%. The median time from referral to first visit decreased by 22 days (35%) from 63 days (interquartile range 21-120 days) in 2010-2011. For people with RA, time from referral to DMARD decreased by 4 days (6%) to 62 days. Male sex, living in metropolitan areas, and having a rheumatologist who used a multidisciplinary care assessment code were associated with shorter times from referral to first DMARD. CONCLUSION: Access to rheumatology care improved, and the increased proportion of patients with IA in the first visits case-mix indicates that rheumatologist supply and incentives for multidisciplinary care may have improved referral patterns. However, time to DMARDs for people with RA remained long, and we found signals of unequal access for female patients and people living outside of metropolitan areas.

Effect of a Billing Code to Reimburse Nurse-Supported Rheumatology Care on Health Care Costs and Access: An Interrupted Time Series Analysis.

OBJECTIVE: This study was undertaken to evaluate the impact of a Multidisciplinary Care Assessment (MCA) billing code on health system costs and access to care in British Columbia (BC). METHODS: Data on all people treated by rheumatologists in BC were obtained from five linked health administrative databases held by Population Data BC from April 1, 2006, to March 31, 2020. Rheumatologists were allocated to either the intervention (ever-billers) or control groups (never-billers). For the intervention group, the index date was the month of the first MCA code billing. For the control group the index dates were imputed from intervention index dates. Our analysis focused on a 48-month period (24 months before and after the index date). We evaluated the impact on two cost (costs related to rheumatoid arthritis [RA]; total health care costs) and access outcomes (rheumatology-related visits per rheumatologist; days between rheumatology visits for patients with RA) using an interrupted time series analysis. RESULTS: A total of 46 rheumatologists (31 intervention and 15 control) met our inclusion criteria. Introduction of the MCA was associated with a small but significant increase in RA-related costs that, at 2 years, translates to a net absolute change of $9.66 per patient per month, but no statistically significant changes in total health care costs. There was no statistically significant change in the number of rheumatology-related visits, but at 2 years there was a net absolute reduction in the median days between rheumatologist visits for patients with RA (6.3 days). CONCLUSION: The introduction of the MCA code was associated with a negligible increase in the RA-related costs and an improvement in access to ongoing care for patients.

The impact of changing the reference countries on the list prices for patented medicines in Canada: A policy analysis.

BACKGROUND: Canada's Patented Medicine Prices Review Board (PMPRB) uses external and internal reference pricing (IRP) to regulate patented drug list prices. PMPRB has changed external reference countries from 7 to 11 to include countries with prices closer to the OECD median. We examined the impact on the list prices for patented medicines had the amendment been implemented from 2013. METHODS: Using IQVIA MIDAS® quarterly sales data, we selected branded products that were launched in Canada in 2013-2018. The list price for each product in each country was calculated as its average annual price during the 3rd year post Canadian launch. The median international price (MIP) was the median of the list prices of PMPRB7 (MIP7) and PMPRB11 (MIP11). We assumed the same IRP would be (scenario 1) or would not be used (scenario 2). RESULTS: Among the selected 400 products, 80.3 % (321) had MIP7 and MIP11 (launched in at least one reference country); 18.3 % did not have MIP11. The total current expenditures were $7,134.4 M. In scenario 1, MIP11 would not be binding for most products and expenditures would decline only by 0.7 %. If IRP were abolished, expenditures might decline by 14.1 % if the launching sequence would not change. CONCLUSIONS: MIP11 might not be binding for most medicines. The impact depends on whether to retain the IRP and approaches taken for medicines without MIP11.

Building Capacity for Injectable Diacetylmorphine and Hydromorphone for the Treatment of Opioid Use Disorder: Identifying Typical Doses.

Identifying typical doses of existing opioid use disorder medications, such as injectable opioid agonist treatment (iOAT), can support client and program needs, and potentially increase iOAT expansion. Longitudinal data from participants in a cohort study (n = 131), along with clinic dispensation records from August 2014 to April 2020, were used to examine physician prescribed as well as used doses of injectable diacetylmorphine and hydromorphone. Dosage groups, by medication and prescribed dose per session, were created for both hydromorphone and diacetylmorphine. A total of 534, 522 injections were registered during the study period among 129 participants. Mean received diacetylmorphine doses ranged from 106 to 989 mg per day, with most clients using 125-262 mg per session (mean 192.99 mg) and attending 2.40 sessions per day. Mean received hydromorphone doses ranged from 51.09 to 696.06 mg per day, with the majority using 88-154 mg per session (mean 121.32 mg; 2.43 sessions). Average daily doses remained stable overtime and, while mid-range doses were most typical, participants used the whole spectrum of allowable dose prescriptions. Evidence supporting typical doses of iOAT can be integrated into program planning to better allow providers and prescribers to anticipate program needs and engage in individualized care.

Health Care Costs Attributable to Prostate Cancer in British Columbia, Canada: A Population-Based Cohort Study.

We aimed to estimate the total health care costs attributable to prostate cancer (PCa) during care phases by age, cancer stage, tumor grade, and primary treatment in the first year in British Columbia (BC), Canada. Using linked administrative health data, we followed a cohort of men aged ≥ 50 years at diagnosis with PCa between 2010 and 2017 (Cohort 1) from the diagnosis date until the date of death, the last date of observation, or 31 December 2019. Patients who died from PCa after 1 January 2010, were selected for Cohort 2. PCa attributable costs were estimated by comparing costs in patients to matched controls. Cohort 1 (n = 22,672) had a mean age of 69.9 years (SD = 8.9) and a median follow-up time of 5.2 years. Cohort 2 included 6942 patients. Mean PCa attributable costs were the highest during the first year after diagnosis ($14,307.9 [95% CI: $13,970.0, $14,645.8]) and the year before death ($9959.7 [$8738.8, $11,181.0]). Primary treatment with radiation therapy had significantly higher costs each year after diagnosis than a radical prostatectomy or other surgeries in advanced-stage PCa. Androgen deprivation therapy (and/or chemotherapy) had the highest cost for high-grade and early-stage cancer during the three years after diagnosis. No treatment group had the lowest cost. Updated cost estimates could inform economic evaluations and decision-making.

The Impact of Injectable Opioid Agonist Treatment (iOAT) on Involvement in Criminalized Activities: A Secondary Analysis from a Clinical Trial in Vancouver, BC.

Purpose: A significant portion of the economic consequences of untreated Opioid Use Disorder (OUD) relate to individuals' involvement in the criminal justice system. The present study uncovers if treatment with iOAT is related to the number of criminal charges amongst participants, what type of crime participants were involved in, and the frequency with which participants were victims of crime. This study contributes to the body of research on the effectiveness of iOAT reducing criminal involvement. Patients and Methods: This is a secondary analysis of police record data obtained from the Vancouver Police Department over a three-year period during the Study to Assess Longer-term Opioid Medication Effectiveness clinical trial. The data was obtained from participants (N = 192) enrolled in the trial through a release of information form. Results: During the three-year period, most charges (45.6%) were property offences, and 25.5% of participants were victims of crime. Participants with no treatment prior to randomization into the SALOME trial were 2.61 (95% CI = 1.64-4.14) more likely to have been charged with a crime than during the iOAT state. Conclusion: IOAT can reduce individuals' involvement with the criminal justice system and is thus a crucial part of the continuum of care. Addiction should be conceptualized as a healthcare rather than criminal issue.

Economic evaluation of prostate cancer risk assessment methods: A cost-effectiveness analysis using population data.

BACKGROUND: The current prostate cancer (PCa) screening standard of care (SOC) leads to unnecessary biopsies and overtreatment because decisions are guided by prostate-specific antigen (PSA) levels, which have low specificity in the gray zone (3-10 ng/mL). New risk assessment tools (RATs) aim to improve biopsy decision-making. We constructed a modeling framework to assess new RATs in men with gray zone PSA from the British Columbia healthcare system's perspective. METHODS: We evaluated the cost-effectiveness of a new RAT used in biopsy-naïve men aged 50+ with a PSA of 3-10 ng/mL using a time-dependent state-transition model. The model was informed by engaging patient partners and using linked administrative health data, supplemented with published literature. The incremental cost-effectiveness ratio and the probability of the RAT being cost-effective were calculated. Probabilistic analysis was used to assess parameter uncertainty. RESULTS: In the base case, a RAT based on an existing biomarker's characteristics was a dominant strategy associated with a cost savings of $44 and a quality-adjusted life years (QALY) gain of 0.00253 over 18 years of follow-up. At a cost-effectiveness threshold of $50,000/QALY, the probability that using a RAT is cost-effective relative to the SOC was 73%. Outcomes were sensitive to RAT costs and accuracy, especially the detection rate of high-grade PCa. Results were also impacted by PCa prevalence and assumptions about undetected PCa survival. CONCLUSIONS: Our findings showed that a more accurate RAT to guide biopsy can be cost-effective. Our proposed general model can be used to analyze the cost-effectiveness of any novel RAT.

Diacetylmorphine versus methadone for the treatment of opioid addiction.

BACKGROUND: Studies in Europe have suggested that injectable diacetylmorphine, the active ingredient in heroin, can be an effective adjunctive treatment for chronic, relapsing opioid dependence. METHODS: In an open-label, phase 3, randomized, controlled trial in Canada, we compared injectable diacetylmorphine with oral methadone maintenance therapy in patients with opioid dependence that was refractory to treatment. Long-term users of injectable heroin who had not benefited from at least two previous attempts at treatment for addiction (including at least one methadone treatment) were randomly assigned to receive methadone (111 patients) or diacetylmorphine (115 patients). The primary outcomes, assessed at 12 months, were retention in addiction treatment or drug-free status and a reduction in illicit-drug use or other illegal activity according to the European Addiction Severity Index. RESULTS: The primary outcomes were determined in 95.2% of the participants. On the basis of an intention-to-treat analysis, the rate of retention in addiction treatment in the diacetylmorphine group was 87.8%, as compared with 54.1% in the methadone group (rate ratio for retention, 1.62; 95% confidence interval [CI], 1.35 to 1.95; P<0.001). The reduction in rates of illicit-drug use or other illegal activity was 67.0% in the diacetylmorphine group and 47.7% in the methadone group (rate ratio, 1.40; 95% CI, 1.11 to 1.77; P=0.004). The most common serious adverse events associated with diacetylmorphine injections were overdoses (in 10 patients) and seizures (in 6 patients). CONCLUSIONS: Injectable diacetylmorphine was more effective than oral methadone. Because of a risk of overdoses and seizures, diacetylmorphine maintenance therapy should be delivered in settings where prompt medical intervention is available. (ClinicalTrials.gov number, NCT00175357.)

Factors associated with absenteeism, presenteeism and activity impairment in patients in the first years of RA.

OBJECTIVES: To understand the impact of the early years of RA on all aspects of work productivity, and determine how this is related to clinical markers. Previous research on work productivity has examined predominantly early retirement and absenteeism. The impact of reduced work performance (presenteeism) and activity impairment is less well understood in early RA populations. METHODS: Working patients enrolled in an RA inception cohort were recruited into a nested study. A questionnaire incorporating the Work Productivity and Activity Impairment (WPAI) instrument was administered with a number of clinical outcomes, including the Multidimensional Health Assessment Questionnaire (MD-HAQ) and scales for pain, fatigue and patient assessment of disease patient global assessment (PtGA). RESULTS: Analysis included 150 RA patients, with the mean age at onset being 48 years (s.d. 10 years) and disease duration from symptom onset being 49 months. Patients had relatively mild disease: MD-HAQ (0.6), pain (3.6), PtGA (3.6) and fatigue (4.6). Of the 92% patients working for pay, 19% reported missing work (absenteeism) in the past week due to their health, accounting for 46% of their working time. Even while at work, ∼25% of actual hours was lost due to poor health, while outside work 33% of patients' regular daily activities were prevented. In multivariate analyses, disease severity was associated with the presence of absenteeism, presenteeism and activity impairment. Patients able to self-schedule their work had lower presenteeism and activity impairment. CONCLUSIONS: Productivity loss is common in patients in the first years of RA who are in paid work and was associated with work characteristics and adverse clinical outcomes.

Work disability rates in RA. Results from an inception cohort with 24 years follow-up.

OBJECTIVE: To explore rates of and reasons for work disability in an early RA cohort with median 10 years follow-up. METHODS: One thousand four hundred and sixty patients with early RA (<2 years symptom duration) and no prior DMARD therapy were recruited from nine rheumatology outpatient departments across the UK between 1986 and 1998. Standard clinical, laboratory and radiological assessments were recorded at 6-monthly and yearly intervals. Assessment of employment included details of type and hours of paid work. The main outcomes investigated were rates of and main reasons for work cessation, analysed by age of onset of RA (<45, 45-60 years) and year of recruitment to the study (before or after 1992). RESULTS: Maximum follow-up was 24 years, median 10 years. Of 647 patients in paid work at baseline, the majority were <60 years old (91%). The estimated probability of stopping work due to RA was highest in patients with older age of onset (45-60 years) who were recruited before 1992, but improved in those recruited from 1992 to 1998 (P < 0.01). There was no difference seen over the study recruitment years in younger age of onset patients. CONCLUSION: Work loss related to RA occurred much earlier than for other reasons, especially in the first 5 years of RA, but improved in the later recruitment period. Work disability is multifactorial, and the gradual changes in therapies used over time in this cohort may be one explanation for the secular differences seen.

Cost-effectiveness of diacetylmorphine versus methadone for chronic opioid dependence refractory to treatment.

BACKGROUND: Although diacetylmorphine has been proven to be more effective than methadone maintenance treatment for opioid dependence, its direct costs are higher. We compared the cost-effectiveness of diacetylmorphine and methadone maintenance treatment for chronic opioid dependence refractory to treatment. METHODS: We constructed a semi-Markov cohort model using data from the North American Opiate Medication Initiative trial, supplemented with administrative data for the province of British Columbia and other published data, to capture the chronic, recurrent nature of opioid dependence. We calculated incremental cost-effectiveness ratios to compare diacetylmorphine and methadone over 1-, 5-, 10-year and lifetime horizons. RESULTS: Diacetylmorphine was found to be a dominant strategy over methadone maintenance treatment in each of the time horizons. Over a lifetime horizon, our model showed that people receiving methadone gained 7.46 discounted quality-adjusted life-years (QALYs) on average (95% credibility interval [CI] 6.91-8.01) and generated a societal cost of $1.14 million (95% CI $736,800-$1.78 million). Those who received diacetylmorphine gained 7.92 discounted QALYs on average (95% CI 7.32-8.53) and generated a societal cost of $1.10 million (95% CI $724,100-$1.71 million). Cost savings in the diacetylmorphine cohort were realized primarily because of reductions in the costs related to criminal activity. Probabilistic sensitivity analysis showed that the probability of diacetylmorphine being cost-effective at a willingness-to-pay threshold of $0 per QALY gained was 76%; the probability was 95% at a threshold of $100,000 per QALY gained. Results were confirmed over a range of sensitivity analyses. INTERPRETATION: Using mathematical modelling to extrapolate results from the North American Opiate Medication Initiative, we found that diacetylmorphine may be more effective and less costly than methadone among people with chronic opioid dependence refractory to treatment.

Sex work involvement among women with long-term opioid injection drug dependence who enter opioid agonist treatment.

BACKGROUND: Substitution with opioid-agonists (e.g., methadone) has shown to be an effective treatment for chronic long-term opioid dependency. Survival sex work, very common among injection drug users, has been associated with poor Opioid Agonist Treatment (OAT) engagement, retention and response. Therefore, this study was undertaken to determine factors associated with engaging in sex work among long-term opioid dependent women receiving OAT. METHODS: Data from a randomized controlled trial, the North American Opiate Medication Initiative (NAOMI), conducted in Vancouver and Montreal (Canada) between 2005-2008, was analyzed. The NAOMI study compared the effectiveness of oral methadone to injectable diacetylmorphine or injectable hydromorphone, the last two on a double blind basis, over 12 months. A research team, independent of the clinic services, obtained outcome evaluations at baseline and follow-up (3, 6, 9, 12, 18 and 24 months). RESULTS: A total 53.6% of women reported engaging in sex work in at least one of the research visits. At treatment initiation, women who were younger and had fewer years of education were more likely to be engaged in sex work. The multivariate logistic generalized estimating equation regression analysis determined that psychological symptoms, and high illicit heroin and cocaine use correlated with women's involvement in sex work during the study period. CONCLUSIONS: After entering OAT, women using injection drugs and engaging in sex work represent a particularly vulnerable group showing poorer psychological health and a higher use of heroin and cocaine compared to women not engaging in sex work. These factors must be taken into consideration in the planning and provision of OAT in order to improve treatment outcomes. TRIAL REGISTRATION: NCT00175357.

The effects of a multiday (10-14 days) subanesthetic dose IV ketamine infusion in the treatment of refractory chronic pain.

Aim: Ketamine is an anesthetic agent that at lower doses can be a potent analgesic. There has been an interest in the use of low dose ketamine in treatment of chronic pain syndromes. Patients & methods: We report the results of a retrospective observational study for patients diagnosed with a chronic noncancer pain syndrome receiving a 2-week continuous subanesthetic IV ketamine infusion. Results & conclusion: We conclude that a 10-14 days of subanesthetic ketamine infusion in chronic patients results in clinically significant lowering of patients' numerical pain score. Further studies looking at subanesthetic ketamine infusion in a prospective trial of multi-day IV ketamine infusion in chronic refractory chronic neuropathic pain are needed to further assess the efficacy of ketamine.

Ketamine is a pharmacological agent that was developed in the 1960s. There has been an increase in interest in the use of ketamine at low doses in the treatment of chronic pain syndromes. In this study, we report the results of a study that investigated patients diagnosed with a chronic noncancer pain syndrome that received a 2-week continuous ketamine infusion. We hypothesized that patients receiving IV ketamine infusion will experience acute and chronic lowering of pain intensity on the numerical rating pain level scale and reduce patient's opioid requirements. We concluded that a 10­14 day of subanesthetic ketamine infusion in chronic patients results in clinically significant lowering of patients' numerical pain score during the ketamine infusion.

A multi-methods and longitudinal study of patients' perceptions in injectable opioid agonist treatment: Implications for advancing patient-centered methodologies in substance use research.

BACKGROUND: Patients' perceptions are vital to the delivery and evaluation of substance use treatment. They are most frequently collected at one time-point and measured using patient satisfaction questionnaires or qualitative methodologies. Interestingly, the findings of these studies often diverge, as satisfaction scores tend to be highly positive, while qualitative findings suggest dissatisfaction and areas for improvement. This divergence limits current understandings of patients' perceptions and their potential change over time in treatment. OBJECTIVE: This study explores the relationship between open-ended positive and negative perceptions of treatment and patient satisfaction scores over time. METHODS: The RUTH (Research on the Utilization of Therapeutic Hydromorphone) prospective cohort study included 131 participants receiving injectable diacetylmorphine or hydromorphone in Canada's first injectable opioid agonist treatment (iOAT) program. The study collected the Client Satisfaction Questionnaire (CSQ-8) at eight time-points over an 18-month period. Following a multi-methods approach, the study complemented the CSQ-8 with open-ended positive and negative comments of iOAT. The research team analyzed these comments thematically at each time-point to develop positive and negative perception themes. We then used growth curve modeling to explore the relationship between positive and negative perception themes and patient satisfaction over time. FINDINGS: Over the eight time-points, six positive and eight negative perception themes emerged, broadly reflecting structural (e.g., expansion of iOAT), process (e.g., schedules), relational (e.g., interactions with providers), and outcome-related (e.g., met/unmet needs) perceptions of iOAT. On average, participants reported high satisfaction (grand mean = 29.2 out of 32), and scores did not significantly change over time. However, we did find significant unexplained variation within participants in their satisfaction trajectories and between participants in their initial satisfaction scores. In conditional growth curve models, the theme "unfavorable interactions with providers" had the strongest independent effect on overall satisfaction trajectories. CONCLUSIONS: This study provides an example of how open-ended comments can be integrated with patient satisfaction questionnaire data to gather a comprehensive and patient-centered evaluation of substance use treatment. Considering the iOAT context specifically, relational dynamics and daily treatment access were significant predictors of patient satisfaction over time and may be attributes of iOAT that require further investigation.