With drug overdoses being the leading cause of accidental death in the United States, knowing the predictors of opioid overdose may help target treatment and prevention efforts to deal with this growing problem, according to Samantha Schiavon, MA, a graduate student in medical and clinical psychology, and her colleagues at the University of Alabama at Birmingham.
They performed a study that found a variety of factors associated with increased risk of opioid overdose, including witnessing an overdose (a friend or others), chronic hepatitis C virus (HCV) infection, and a higher frequency of distinct buprenorphine treatment episodes.
Data were acquired during Nov. 2015-July 2017 from an ongoing study to determine the impact of the distribution of naloxone kits to individuals at high risk for opioid overdose. All 247 participants included were considered at high risk of opioid overdose because they were recruited from sites providing opioid addiction treatment, including a residential drug treatment facility (43%), inpatient treatment following ED admittance (25%), and criminal justice supervision (32%). Of the participants, 57% were male, with a mean age of around 34 years; most were white (89%).
Participants were assessed using a self-reporting 30-item questionnaire regarding chronic medical conditions, STIs, past and current opioid misuse, nonfatal opioid overdose experiences, and frequency of every distinct opioid treatment episode including buprenorphine, methadone maintenance clinics, residential drug rehabilitation programs, and intensive outpatient treatment. All variables were answered on a 5-point scale ranging from 0 (never) to 4 (more than three times), according to the researchers.
Participants who witnessed a friend’s overdose (odds ratio, 4.21; 95% confidence interval, 1.99-8.89) showed the highest risk of personal overdose, while having witnessed others overdose at a higher frequency carried a lower increased risk (OR, 1.42; 95% CI, 1.11-1.82).
HCV infection was associated with a more than twofold increase in overdose risk (OR, 2.44; 95% CI, 1.20-4.97), likely because of the strong association between HCV and heroin injection drug use, according to the researchers. They added that this association may be an indicator of higher-risk injection behavior, including needle sharing. They also suggested that, given the current epidemiology of HCV infection, identifying HCV infections may benefit younger populations who may be at risk of an overdose from riskier injection practices or where injection drug risk is not yet known.
The researchers reported that a higher frequency of distinct buprenorphine treatment episodes also led to increased risk (OR, 1.55; 95% CI, 1.17-2.07), whereas a greater frequency of distinct methadone treatment episodes was related to decreased odds of experiencing a nonfatal overdose (OR, 0.67; 95% CI, 0.49-0.91) according to their report published in Addictive Behavior ().
In addition, those who experienced a past opioid overdose were more likely to have obtained methadone illicitly (65%; P less than or equal to .001) or have a friend who died from an overdose (90%; P = .001) compared with those who have not experienced an overdose, according to the researchers.
“The current study strongly contributes to our understanding of risk factors of experiencing an opioid overdose. The knowledge gained from this study may enable targeted treatment interventions to reduce preventable deaths from opioid overdose,” according to the researchers. In particular, they pointed out the increased risk of overdose with the use of illicitly obtained methadone and suggested that expanded access to medication-assisted treatments be made available to all patients. “Opioid antagonist medications such as naltrexone may be particularly helpful in preventing opioid overdose for patients leaving controlled environments such as hospital, drug treatment, and correctional facilities,” they concluded.
The researchers reported that they had no conflicts of interest.
SOURCE: Schiavon S et al. .