The number of opioid-related overdose deaths in the United States is estimated to have increased 6-fold over the past 2 decades.1 In 2017, more than two-thirds of drug overdose deaths involved opioids, yielding a mortality rate of 14.9 per 100,000.2 Not only does the opioid epidemic currently pose a significant public health crisis characterized by high morbidity and mortality, but it is also projected to worsen in coming years. According to Chen and colleagues, opioid overdose deaths are estimated to increase by 147% from 2015 to 2025.3 That projects almost 82,000 US deaths annually and > 700,000 deaths in this period—even before accounting for surges in opioid overdoses and opioid-related mortality coinciding with the COVID-19 pandemic.3,4
As health systems and communities globally struggle with unprecedented losses and stressors introduced by the pandemic, emerging data warrants escalating concerns with regard to increased vulnerability to relapse and overdose among those with mental health and substance use disorders (SUDs). In a recent report, the American Medical Association estimates that opioid-related deaths have increased in more than 40 states with the COVID-19 pandemic.4
Veterans are twice as likely to experience a fatal opioid overdose compared with their civilian counterparts.5 While several risk mitigation strategies have been employed in recent years to improve opioid prescribing and safety within the US Department of Veterans Affairs (VA), veterans continue to overdose on opioids, both prescribed and obtained illicitly.6 Variables shown to be strongly associated with opioid overdose risk include presence of mental health disorders, SUDs, medical conditions involving impaired drug metabolism or excretion, respiratory disorders, higher doses of opioids, concomitant use of sedative medications, and history of overdose.6-8 Many veterans struggle with chronic pain and those prescribed high doses of opioids were more likely to have comorbid pain diagnoses, mental health disorders, and SUDs.9 Dashboards and predictive models, such as the Stratification Tool for Opioid Risk Mitigation (STORM) and the Risk Index for Overdose or Serious Opioid-induced Respiratory Depression (RIOSORD), incorporate such factors to stratify overdose risk among veterans, in an effort to prioritize high-risk individuals for review and provision of care.6,10,11 Despite recent recognition that overdose prevention likely requires a holistic approach that addresses the biopsychosocial factors contributing to opioid-related morbidity and mortality, it is unclear whether veterans are receiving adequate and appropriate treatment for contributing conditions.
There are currently no existing studies that describe health service utilization (HSU), medication interventions, and rates of opioid-related adverse events (ORAEs) among veterans after survival of a nonfatal opioid overdose (NFO). Clinical characteristics of veterans treated for opioid overdose at a VA emergency department (ED) have previously been described by Clement and Stock.12 Despite improvements that have been made in VA opioid prescribing and safety, knowledge gaps remain with regard to best practices for opioid overdose prevention. The aim of this study was to characterize HSU and medication interventions in veterans following NFO, as well as the frequency of ORAEs after overdose. The findings of this study may aid in the identification of areas for targeted improvement in the prevention and reduction of opioid overdoses and adverse opioid-related sequelae.
Methods
This retrospective descriptive study was conducted at VA San Diego Healthcare System (VASDHCS) in California. Subjects included were veterans administered naloxone in the ED for suspected opioid overdose between July 1, 2013 and April 1, 2017. The study population was identified through data retrieved from automated drug dispensing systems, which was then confirmed through manual chart review of notes associated with the index ED visit. Inclusion criteria included documented increased respiration or responsiveness following naloxone administration. Subjects were excluded if they demonstrated lack of response to naloxone, overdosed secondary to inpatient administration of opioids, received palliative or hospice care during the study period, or were lost to follow-up.
Data were collected via retrospective chart review and included date of index ED visit, demographics, active prescriptions, urine drug screen (UDS) results, benzodiazepine (BZD) use corroborated by positive UDS or mention of BZD in index visit chart notes, whether overdose was determined to be a suicide attempt, and naloxone kit dispensing. Patient data was collected for 2 years following overdose, including: ORAEs; ED visits; hospitalizations; repeat overdoses; fatal overdose; whether subjects were still alive; follow-up visits for pain management, mental health, and addiction treatment services; and visits to the psychiatric emergency clinic. Clinical characteristics, such as mental health disorder diagnoses, SUDs, and relevant medical conditions also were collected. Statistical analysis was performed using Microsoft Excel and included only descriptive statistics.