MDH’s Injury and Violence Prevention Section monitors all deaths and leading causes of hospitalizations and emergency department visits related to injuries. Beginning in 2011-2012, the growing numbers and rates of overdose deaths reached a level where it became necessary to monitor and report them separately from other types of injury and violence. Since then, MDH has reported this data annually.
Overview
Overdose deaths are preventable. Drug overdose death reporting is an important public health charge. On an individual level, it allows MDH and others to understand the circ*mstances that may have led to a person’s death. On a population level, it allows MDH, local public health agencies, treatment providers, and community stakeholders to better understand characteristics of drugs used and demographics of people who die from opioid overdoses to improve prevention efforts across the state. It provides the public with important information to keep them informed about what is happening in their state.
Causes and locations of overdose deaths
Opioid overdose deaths are usually caused by prescription opioids that may or may not have been prescribed to a person, heroin, fentanyl, and/or other synthetic opioids. They can happen anywhere. Common settings where overdose deaths occur include private residences, hospitals, and in other public community settings. The manner of overdose deaths are most commonly found to be accidental/unintentional, suicide, or undetermined. An accidental death is one that was totally unforeseen and unexpected.
Overdose death investigations
Deaths suspected to be caused by drug overdose are usually investigated by a medical examiner or coroner. They determined the manner of death (accidental/unintentional, suicide, etc.) by investigating the circ*mstances around the death.
Circ*mstances can include:
- Scene findings
- Autopsy results
- Toxicology results
- Health history
Medical examiners and coroners record their findings on a death certificate. Death certificates include the information listed above, along with demographic information about the person who died. If you would like more information on the medical examiner/coroner death investigation process, visit the Office of Justice Program’s Death Investigation: A Guide for the Scene Investigator (PDF)
Data sources
MDH receives data on overdose deaths from:
- Death certificates of Minnesota residents
- Information and notes from death scene investigations
- Medical/EMS records
- Public health lab results
To find statewide and county-level data on nonfatal and fatal overdoses, visit the Minnesota Injury Data Access System (MIDAS).
The manner of death, based on the investigation of the circ*mstances by a coroner or state medical examiner, is determined to be:
- Natural
- Accidental/unintentional
- Suicide
- Homicide
- Undetermined
Circ*mstances included in the cause of death investigation are:
- Scene findings
- Autopsy results
- Toxicology reports
- Health history
In an opioid overdose death, scene findings may include:
- Frothy ‘foam cone’ from the mouth
- Intact pills in the stomach
- Needles present at the scene
- Prescription history
- Pill counts
- Needle track marks
- Prescription pills at the scene
An indicator that a particularly potent product was involved in the death, like fentanyl or carfentanyl, includes when a needle is still in the person’s arm or body, indicating an almost instantaneous death upon injection.
Opioid overdose death resulting from a prescription opioid is usually classified as an accidental or undetermined death. Often there is an assumption that when the death involves prescription medications prescribed to the person who died, that this person was using the prescription medications appropriately, as prescribed, and without risk for overdose. With prescription pain pills, it is difficult to determine if the pills were used as prescribed by the decedent, obtained from family or friends for a pain-related reason, or bought with an intent to get high. If a person dies of a natural cause, for example a heart attack or infectious disease, that death would be categorized as natural, even if prescription opioids are found at the scene or prescribed in the patient’s history. This may contribute to an under-reporting of opioid-related deaths.
One of the most challenging ethical considerations for medical examiners and coroners is their role in determining intent, or attempting to figure out what a person was trying or not trying to do before they died. There is a substantial amount of variability among medical examiners’ and coroners’ approach to a death investigation. For example, while one medical examiner might determine an overdose death to be an accidental poisoning, another medical examiner would say that it is undetermined because there was no witness, and no way to rule out that it was suicide or homicide.
Opioid overdose deaths are most commonly found to be an accidental/unintentional death. Accidental death is operationally defined to be totally unforeseen and unexpected. Some medical examiners or coroners, however, may say that that if heroin was injected in a body, that a resulting death cannot be understood as totally unforeseen and unexpected, therefore, this heroin death may be determined to be a suicide or undetermined. In order for a death to be classified as a suicide, there must be evidence of the intent to die, such as a suicide note found at the scene.
To determine burden of proof, the general guidelines in coroner and state medical examiner’s training state there needs to be:
- 50% reasonable probability for natural deaths
- 70% preponderance of evidence for accidental deaths
- 90% clear and convincing evidence for suicide deaths
- more than 90% beyond a reasonable doubt for homicide deaths
- 100% beyond a doubt for any cause of death
Some medical examiners would require “beyond a reasonable doubt” or more than 90% certainty in order to determine the burden of proof for a suicide. The amount, detail, and reliability of evidence is limited, sometimes difficult to obtain, and often incomplete.
Toxicology results are very useful in determining the drug type(s) and dosage; however, they do not measure anything about the user’s tolerance. It is common for findings to be ambiguous in opioid overdose death investigations. For example, the person may have had a history of depression, a history of chronic pain, a past non-fatal overdose with unclear intent, ambiguous residual pill counts, and/or the toxicology results are very high for opioids, but ambiguous for intent.
All of these factors make interpreting toxicology results and death investigations complex, and subsequently difficult to determine the cause of death with a high degree of certainty.
Melissa Pasquale, MD is a Forensic Pathologist and works for the Office of Chief Medical Examiner in Atlanta, Georgia and presented at the annual Center for Disease Control (CDC) Prevention for States Conference.
Please visit the Opioid Dashboard for more information on opioid overdose death, nonfatal overdose, use, misuse, substance use disorder, prescribing practices, supply, diversion, harm reduction, co-occurring conditions, and social determinants of health.
