Opioid overdose. Trends, risk factors, interventions and priorities for action

International illicit production of opioids has increased in recent years, as has illicit opioid use in many countries, especially the injection of heroin. The number of opioid overdose deaths, though difficult to assess, appears to have risen in a number of countries over the past decade but lack of agreement on the definition and classification of opioid overdoses and other drug-related deaths hampers comparisons between countries. There are many difficulties in defining and recording overdose and other drug-related deaths. Reliable cause-specific mortality data for opioid users is particularly lacking.
Research from a number of countries suggests that individual variations in tolerance and polydrug use are contributory factors to fatal and non-fatal opioid (primarily heroin) overdoses. Despite this evidence the view persists that opioid purity is the sole cause of opioid overdose deaths. This diverts attention away from potentially modifiable factors that may reduce overdose deaths. It also de-emphasizes the fact that overdoses often occur in the company of others which provide an opportunity to intervene. Delays in response to overdoses may be a major remediable cause of overdose deaths.
Deaths from heroin and other opioid overdose could potentially be reduced by: educating opioid users about the risks of polydrug use and injecting alone through, for example, peer outreach and social networks; improving their responses to the overdose of others, for example, by reducing fears of seeking emergency or medical assistance; teaching basic skills in cardiopulmonary resuscitation (CPR) to keep overdose victims alive until help arrives, and increasing the number of opioid users in treatment, particularly older heroin users, in methadone maintenance treatment.
Priorities for action include: better definitions and recording of opioid overdose and other drugrelated deaths; the implementation and evaluation of preventive interventions based upon available knowledge; and more studies of risk factors for non-fatal and fatal opioid overdoses to improve preventive interventions. (Editor's abstract)