Outcomes associated with hospital admissions for accidental opioid overdose in British Columbia: a retrospective cohort study

Associations with experience of non-fatal opioid overdose in British Columbia, Canada: a repeated cross sectional survey study

INTRODUCTION

Lives lost in North America due to the unregulated drug poisoning emergency are preventable and those who survive an opioid overdose may suffer long-term disability. Rates of opioid overdose more than doubled following the onset of the COVID-19 pandemic in British Columbia, Canada.

MATERIALS AND METHODS

Our analytical sample was comprised of 1447 participants from the 2018, 2019, and 2021 Harm Reduction Client Survey who responded yes or no to having experienced an opioid overdose in the past 6 months. Participants were recruited from harm reduction sites from across British Columbia. We used logistic regression to explore associations of experiencing an opioid overdose.

RESULTS

Overall, 21.8% of participants reported experiencing an opioid overdose in the last six months (18.2% in 2019 and 26.6% in 2021). The following factors were positively associated with increased adjusted odds of experiencing a non-fatal opioid overdose: cis men relative to cis women (AOR 1.49, 95% CI 1.10-2.02), unstably housed compared to people with stable housing (AOR 1.87, 95% CI 1.40-2.50), and participants from 2021 compared to those from 2019 (AOR 3.06, 95% CI 1.57-5.97). The effects of both previous experience of a stimulant overdose and having witnessed an opioid overdose depended on the year of study, with both effects decreasing over subsequent years.

CONCLUSIONS

Overdoses have increased over time; in 2021 more than one in four participants experienced an overdose. There is an urgent need for policy and program development to meaningfully address the unregulated drug poisoning emergency through acceptable life-saving interventions and services to prevent overdoses and support overdose survivors.

Incidence of rhabdomyolysis occurrence in psychoactive substances intoxication: a systematic review and meta-analysis

Rhabdomyolysis is a potentially life-threatening condition induced by diverse mechanisms including drugs and toxins. We aimed to investigate the incidence of rhabdomyolysis occurrence in intoxicated patients with psychoactive substances. In this review, three databases (PubMed, Scopus, Web of Science) and search engine (Google Scholar) were searched by various keywords. After the screening of retrieved documents, related data of included studies were extracted and analyzed with weighted mean difference (WMD) in random effect model. The highest incidence of rhabdomyolysis was observed in intoxication with heroin (57.2 [95% CI 22.6-91.8]), amphetamines (30.5 [95% CI 22.6-38.5]), and cocaine (26.6 [95% CI 11.1-42.1]). The pooled effect size for blood urea nitrogen (WMD = 8.78, p = 0.002), creatinine (WMD = 0.44, p < 0.001), and creatinine phosphokinase (WMD = 2590.9, p < 0.001) was high in patients with rhabdomyolysis compared to patients without rhabdomyolysis. Our results showed a high incidence of rhabdomyolysis induced by psychoactive substance intoxication in ICU patients when compared to total wards. Also, the incidence of rhabdomyolysis occurrence was high in ICU patients with heroin and amphetamine intoxication. Therefore, clinicians should anticipate this complication, monitor for rhabdomyolysis, and institute appropriate treatment protocols early in the patient's clinical course.

Association between toxic drug events and encephalopathy in British Columbia, Canada: a cross-sectional analysis

BACKGROUND

Encephalopathy can occur from a non-fatal toxic drug event (overdose) which results in a partial or complete loss of oxygen to the brain, or due to long-term substance use issues. It can be categorized as a non-traumatic acquired brain injury or toxic encephalopathy. In the context of the drug toxicity crisis in British Columbia (BC), Canada, measuring the co-occurrence of encephalopathy and drug toxicity is challenging due to lack of standardized screening. We aimed to estimate the prevalence of encephalopathy among people who experienced a toxic drug event and examine the association between toxic drug events and encephalopathy.

METHODS

Using a 20% random sample of BC residents from administrative health data, we conducted a cross-sectional analysis. Toxic drug events were identified using the BC Provincial Overdose Cohort definition and encephalopathy was identified using ICD codes from hospitalization, emergency department, and primary care records between January 1st 2015 and December 31st 2019. Unadjusted and adjusted log-binomial regression models were employed to estimate the risk of encephalopathy among people who had a toxic drug event compared to people who did not experience a toxic drug event.

RESULTS

Among people with encephalopathy, 14.6% (n = 54) had one or more drug toxicity events between 2015 and 2019. After adjusting for sex, age, and mental illness, people who experienced drug toxicity were 15.3 times (95% CI = 11.3, 20.7) more likely to have encephalopathy compared to people who did not experience a drug toxicity event. People who were 40 years and older, male, and had a mental illness were at increased risk of encephalopathy.

CONCLUSIONS

There is a need for collaboration between community members, health care providers, and key stakeholders to develop a standardized approach to define, screen, and detect neurocognitive injury related to drug toxicity.

Outcomes and Healthcare Utilization Among New Persistent Opioid Users and Nonopioid Users After Curative-intent Surgery for Cancer

OBJECTIVE

The aim of the study was to compare the health outcomes and resource use of cancer patients who were new persistent opioid users with those who were not, after undergoing curative intent surgery for cancer.

BACKGROUND

Little is known about long-term health outcomes (overdose, mortality) and resource utilization of new persistent opioid users among cancer patients undergoing curative-intent surgery.

METHODS

This retrospective cohort study included all adults with a diagnosis of solid cancers who underwent curative-intent surgery during the study period (2011-2015) in Alberta, Canada and were opioid-naïve before surgery, with a follow-up period until December 31, 2019. The key exposure, "new persistent opioid user," was defined as a patient who was opioid-naive before surgery and subsequently filled at least 1 opioid prescription between 60 and 180 days after surgery. The primary outcome was opioid overdose that occurred within 3 years of surgery. All-cause death, noncancer caused death, and department visit (yes vs. no), and hospitalization (yes vs. no) in the follow-up periods were also included as outcomes.

RESULTS

In total, 19,219 patients underwent curative intent surgery with a median follow-up of 47 months, of whom 1530 (8.0%) were identified as postoperative new persistent opioid users. In total, 101 (0.5%) patients experienced opioid overdose within 3 years of surgery. Compared with nonopioid users, new persistent opioid users experienced a higher rate of opioid overdose (OR = 2.37, 95% CI: 1.44-3.9) within 3 years of surgery. New persistent opioid use was also associated with a greater likelihood of being hospitalized (OR = 2.03, 95% CI: 1.76-2.33) and visiting an emergency room (OR = 1.83, 95% CI: 1.62-2.06) in the first year after surgery, and a higher overall (HR = 1.28, 95% CI: 1.1-1.49) and noncancer caused mortality (HR = 1.33, 95% CI: 1.12-1.58), when compared with nonopioid users.

CONCLUSION

Postoperative new persistent opioid use among cancer patients undergoing curative-intent surgery is associated with subsequent opioid overdose, worse survival, and more health resource utilization.

National trends in population rates of opioid-related mortality, hospitalization and emergency department visits in Canada between 2000 and 2017. A population-based study

BACKGROUND AND AIMS

Existing assessments of the time-trends of opioid-related mortality, hospitalization and emergency department visits in Canada have relied mainly on provincial databases, while national assessments generally do not provide information before 2016. We aimed to estimate Canadian national time trends in opioid-related mortality from 2000 to 2017 and opioid-related hospitalization and emergency department visits between 2000 and 2012.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

Residents of all Canadian provinces and territories for which comparable data were available from 2000 to 2017.

MEASUREMENTS

We identified opioid-related mortality, hospitalization and emergency department visits using validated algorithms using ICD codes from administrative databases. We calculated crude rates and sex- and age-adjusted rates per million. For hospitalizations, we calculated case-fatality, 90-day and 365-day all-cause mortality and opioid-related re-hospitalization rates. We used Poisson regression to examine the significance of the time trend.

FINDINGS

From 2000 to 2017, the adjusted opioid mortality rate in Canada (outside Quebec) increased significantly by 592.9% (from 20.0 opioid deaths per million in 2000 to 118.3 in 2017). The highest year-to-year increases were from 2015 to 2016 (31.8%) and from 2016 to 2017 (52.2%). The adjusted hospitalizations doubled significantly during the study period (an increase of 103.7%, from 159.7 opioid hospitalizations per million Canadians in 2000 to 325.3 in 2012). The adjusted rate of emergency department visits increased significantly by 188.7% (from 280.6 per million in 2000 to 810.1 in 2012). Case-fatality was 2.3% overall and was mainly constant during the study period. Both 90- and 365-day all-cause mortality increased significantly between 2000 and 2011 (from 1.7 to 3.1% and 3.9 to 7.4%, respectively), while re-hospitalization for opioid-related diagnoses was reduced (from 7.8 to 6.4% and 14.2 to 12.9%, respectively).

CONCLUSIONS

Opioid-related mortality, hospitalization and emergency department visits in Canada have been increasing gradually since 2000.

Relationship Between Cardiovascular Disease Pathology and Fatal Opioid and Other Sedative Overdose: A Post-Mortem Investigation and Pilot Study

Introduction: In 2019, Scotland reported the highest number of drug deaths amongst EU countries. Of the 1,264 drug deaths reported in 2019, 94% were related to polysedative use. Studies have proposed a relationship between opioid use and cardiovascular disease. Furthermore, the concomitant use of sedatives and opioids has been associated with lethal cardiopulmonary events. However, evidence is still limited for the relationship between polysedative use and cardiovascular diseases. Thus, the present study aimed to investigate the association between polysedative use and the underlying cardiovascular pathologies in drug deaths.

Methods: This study consisted of a post-mortem investigation of 436 drug deaths. Data extracted from post-mortem reports included socio-demographic characteristics (e.g., gender, age), cardiovascular pathologies (e.g., atherosclerosis, atheroma, and inflammation), in addition to the presence of opioids (e.g. methadone, heroin) and other substances (e.g., alcohol, benzodiazepine) in the blood of the deceased. Stepwise multiple regression models were employed to identify which substances predicted cardiovascular pathologies.

Results: The presence of opioids, benzodiazepines, and alcohol in the blood of the deceased predicted overall cardiovascular disease (CVD) severity [R2 = 0.33, F (5, 430) = 39.64, p < 0.0001; adjusted R2 = 0.32, f2 = 0.49]. Positive Beta coefficients may indicate an exacerbation of CVD (B = 0.48 95% CI = 0.25, 0.70) due to the presence of opioids in the blood of the deceased. Negative associations may instead indicate a relative protective effect of alcohol (B = −0.2, 95% CI = −0.41, −0.00) and benzodiazepines (B = −0.29, 95% CI = −0.48, −0.09) on CVD.

Conclusion: These findings may inform national clinical guidelines on the need to monitor individuals who abuse opioids for presence of cardiovascular disease risk factors pathologies and provide timely interventions to reduce mortality in the population.

Neurocognitive impairments and brain abnormalities resulting from opioid-related overdoses: A systematic review

BACKGROUND

Non-fatal opioid-related overdoses have increased significantly over the past two decades and there have been increasing reports of brain injuries and/or neurocognitive impairments following overdose events. Limited preclinical research suggests that opioid overdoses may cause brain injury; however, little is known about such injuries in humans. The purpose this systematic review is to summarize existing studies on neurocognitive impairments and/or brain abnormalities associated with an opioid-related overdose in humans.

METHODS

PubMed, Web of Science, Ovid MEDLINE and PsyINFO were searched, without year restrictions, and identified 3099 articles. An additional 24 articles were identified by reviewing references. Articles were included if they were published in English, reported study findings in humans, included individuals 18 years of age or older, and reported an objective measure of neurocognitive impairments and/or brain abnormalities resulting from an opioid-related overdose. Six domains of bias (selection, performance, attrition, detection (two dimensions) and reporting were evaluated and themes were summarized.

RESULTS

Seventy-nine journal articles, published between 1973-2020, were included in the review. More than half of the articles were case reports (n = 44) and there were 11 cohort studies, 18 case series, and 6 case-control studies. All of the studies were categorized as at-risk of bias, few controlled for confounding factors, and methodological differences made direct comparisons difficult. Less than half of the studies reported toxicology results confirming an opioid-related overdose; 64.6 % reported brain MRI results and 27.8 % reported results of neuropsychological testing. Only two studies had within subject comparative data to document changes in the brain possibly associated with an overdose. Despite these limitations, existing publications suggest that brain injuries and neurocognitive impairments are associated with opioid overdose. Additional research is needed to establish the incidence of overdose-related brain injuries and the potential impact on functioning, as well as engagement in treatment of substance use disorders.

CONCLUSIONS

Respiratory depression is a defining characteristic of opioid overdose and prolonged cerebral hypoxia may cause brain injuries and/or neurocognitive impairments. The onset, characteristics, and duration of such injuries is variable and additional research is needed to understand their clinical implications.

Trends and outcomes of serious complications associated with non-fatal opioid overdoses in Ontario, Canada

BACKGROUND

Non-fatal opioid overdoses can lead to serious complications and consequently, long-term health effects. We sought to characterize trends of hospitalizations for serious complications associated with opioid overdoses in Ontario, Canada and report health services utilization and mortality in the year following hospital discharge.

METHODS

We conducted a cross-sectional study in Ontario among individuals who experienced a hospitalization for a serious complication (required intubation, rhabdomyolysis, or a brain injury) associated with an opioid overdose between 2010 and 2019. We examined inpatient characteristics at the time of hospital admission, and health services utilization and mortality rates in the year following hospital discharge.

RESULTS

The rate of hospitalizations for serious complications associated with opioid overdoses increased by 66.7 % from 1.8 per 100,000 population in 2010 to 3.0 per 100,000 population in 2019 in Ontario. Individuals that were discharged alive from hospital experienced high health services utilization in the following year; 71.2 % (N = 953 of 1,338) visited the emergency department (ED), 34.2 % (N = 458) were admitted to hospital, and 16.4 % (N = 219) were treated in hospital for an opioid overdose. However only a quarter of individuals (N = 332; 24.8 %) initiated on opioid agonist therapy within 90 days. Additionally, 8.0 % (N = 127) of hospitalizations resulted in death within 1 year.

CONCLUSIONS

This study highlights increasing rates of serious complications associated with opioid overdoses, with a high demand of health services and a high mortality rate in the following year. These findings highlight an ongoing need for support and harm reduction services to allow for early intervention and follow-up care.

Individualized prescribing portraits to reduce inappropriate initiation of opioid analgesics to opioid naïve patients in primary care: Protocol for a randomized controlled trial

Background Opioid analgesics are frequently initiated for chronic and acute pain despite weak evidence of benefit, although prescribing rates of some analgesics decreased in the context of the epidemic. In some populations, up to a quarter of opioid naïve persons prescribed opioids for non-cancer pain develop prescription opioid use disorder (OUD). Audit and feedback interventions rely on constructive use of routinely collected data to align professional behaviours and clinical practice with best evidence. These interventions have been shown to help reduce inappropriate initiation. However, effectiveness and acceptability of individualized "portraits" of physicians' prescribing patterns, to reduce inappropriate initiation of opioid analgesics to opioid naïve persons, have not been evaluated. Methods REDONNA is a mixed-methods randomized study testing the effectiveness of individualized prescribing Portraits to reduce inappropriate initiation of opioid analgesics. This intervention to improve safety of opioid prescribing in primary care in British Columbia (BC), Canada involves mailing individual prescribing portraits to an 'early group' of 2604 family physicians, followed in 6 months by a mailing to 2553 family physicians in the 'delayed group'. Primary outcome is number of new opioid prescriptions initiated in opioid naïve people, measured using administrative data from a centralized medication monitoring database covering all prescription opioids dispensed from BC community pharmacies. Secondary endpoints will compare prescribing impact between the two groups. A qualitative sub-study will examine feasibility among a purposive sample of physicians and patients. Discussion This trial provides important evidence on the intervention's potential to steer policy and practice on inappropriate opioid analgesics initiation. Trial registration: The study was registered prospectively on 30 March 2020 at the ISRCTN Register (https://www.isrctn.com/ISRCTN34246811).

Opioid-Associated Out-of-Hospital Cardiac Arrest: Distinctive Clinical Features and Implications for Health Care and Public Responses: A Scientific Statement From the American Heart Association

Opioid overdose is the leading cause of death for Americans 25 to 64 years of age, and opioid use disorder affects >2 million Americans. The epidemiology of opioid-associated out-of-hospital cardiac arrest in the United States is changing rapidly, with exponential increases in death resulting from synthetic opioids and linear increases in heroin deaths more than offsetting modest reductions in deaths from prescription opioids. The pathophysiology of polysubstance toxidromes involving opioids, asphyxial death, and prolonged hypoxemia leading to global ischemia (cardiac arrest) differs from that of sudden cardiac arrest. People who use opioids may also develop bacteremia, central nervous system vasculitis and leukoencephalopathy, torsades de pointes, pulmonary vasculopathy, and pulmonary edema. Emergency management of opioid poisoning requires recognition by the lay public or emergency dispatchers, prompt emergency response, and effective ventilation coupled to compressions in the setting of opioid-associated out-of-hospital cardiac arrest. Effective ventilation is challenging to teach, whereas naloxone, an opioid antagonist, can be administered by emergency medical personnel, trained laypeople, and the general public with dispatcher instruction to prevent cardiac arrest. Opioid education and naloxone distributions programs have been developed to teach people who are likely to encounter a person with opioid poisoning how to administer naloxone, deliver high-quality compressions, and perform rescue breathing. Current American Heart Association recommendations call for laypeople and others who cannot reliably establish the presence of a pulse to initiate cardiopulmonary resuscitation in any individual who is unconscious and not breathing normally; if opioid overdose is suspected, naloxone should also be administered. Secondary prevention, including counseling, opioid overdose education with take-home naloxone, and medication for opioid use disorder, is important to prevent recurrent opioid overdose.