Suicide might be a root cause of more opioid overdoses than we thought

Updated: Mar 12, 2020

By Mark Gold, MD

An “intentional” suicide attempt by fatal drug overdose refers to an individual seeking to overdose in order to end her life. This may sound straightforward enough. But the issue is much more nuanced, related to how we understand and respond to the opioid overdose epidemic. If all overdoses are considered “accidental” until proven otherwise, we may be missing higher rates of suicide and depression, and different approaches to prevention, identification, and treatment.

How exactly can coroners and officials who write on death certificates determine whether someone “intentionally” wanted to die by overdose or “unintentionally” died by overdose, without any desire to die at all? The Directors of the National Institute of Mental Health (NIMH) and National Institute on Drug Abuse (NIDA) recently reviewed the literature linking overdose and suicide.1 Up to 30 percent of all accidental overdoses are actually suicides. They observed that, controlling for other conditions, suicidal thoughts are 40-50 percent higher among individuals misusing prescription opioids, and that, “people with a prescription opioid use disorder were also twice as likely to attempt suicide as individuals who did not misuse prescription opioids.”

In the U.S., suicide rates are increasing, overdoses are increasing, and life expectancy is decreasing—“deaths of despair”, they are often called. Between 1999 and 2009, opioid-related suicide rates doubled.2 Opioid-related overdose deaths among Americans and adolescents have also surged. And both opioid-related deaths and suicides have increased to epidemic levels in the United States. Doctors Nora D. Volkow and Maria A. Oquendo3 have written that declining motivation to live can range “from engagement in increasingly risky behaviors despite a lack of conscious suicidal intent to frank suicidal ideation and intent.” Most of what we used to think as leading causes of death have been decreasing. Deaths due to cardiovascular disease, cancer, stroke, and lung disease have all been steadily decreasing since 2000. But deaths from drugs, alcohol, and suicide have been increasing. Things have changed so much and so fast that more U.S. deaths now result from self-harm than even diabetes.4 Suicide is more than twice as common as homicide in the United States. Accidents, which may sometimes be covert suicide, make up the other leading causes of death. The major default manner-of-death assignment for injury cases contain misclassified suicides.5

Yet little attention has been paid to these deaths’ contributions to overdoses, suicide, and addiction.6 In a recent study, nationally recognized research leaders explore the connection between opioid-related overdoses and the spectrum of suicidal motivation.

What did this study find about opioid overdoses and suicide?

This study found “that a significant number of treatment-seeking patients with OUD have suicidal motivation prior to nonfatal opioid overdoses.” We know that drug use, alcohol use, and substance use disorders are often accompanied by depression. Experts have debated this chicken and egg for years—which comes first, depression or opioid use? Suicidal motivations may be better understood as a background or underlying continuous issue for patients with SUDs, a “continuum” along which the drive to complete suicide varies over time. Quantitative analyses of suicidal motivation before overdose is a gap in research on the topic, and this study set out to measure the extent to which patients with OUD may experience varying degrees of suicidal motivation.

This Harvard, McLean Hospital study asked participants about their “desire to die” before their most recent opioid overdose, and their perception of how likely they were to overdose. Participants filled out questionnaires and rated their suicidal motivation and the likelihood of overdose on scales from 0-10. For suicidal motivation, a rating of 0 meant “no desire to die” and a 10 meant “I definitely wanted to die.” For the likelihood of overdose, 0 meant “no risk of death” and 10 meant “I definitely thought I would die.” This study recruited participants from an inpatient detoxification/stabilization unit. 120 patients over the age of 18 completed this study’s measures. Their mean age was 34, 85 percent were white, and 41 percent were women. 60 percent had a psychiatric disorder, 26 percent were receiving mental health treatment, and 32 percent had attempted suicide in the past. In order to participate, this study required patients to be undergoing substance use disorder treatment, and to provide written consent.

An astounding 58.5 percent of participants said that they had at least some desire to die before their most recent opioid overdose, and only 41.5 percent said that they did not want to die, a 0/10. This is quite remarkable when you remember that we had assumed all overdoses were accidental until recent work began to really look at the association between depression and overdose. 36 percent said that they had a strong desire to die, a score greater than 7/10. 21 percent reported 10/10, “I definitely wanted to die.” 30.2 percent of participants said that they believed it was “not at all likely” they’d overdose, or 0/10. 13.2 percent said that it was “extremely likely,” 10/10. This study also found that 92 percent of participants tended to have used heroin of fentanyl. It suggests that the results are consistent with the idea of suicidal motivation as a spectrum, given variations in participant responses about the desire to die, and that suicidal motivation before opioid overdose is “common.”

Why is this important?

Dr. Hilary Connery and her Harvard University coauthors write that, “the classification of a drug overdose as either ‘unintentional’ or ‘intentional’ may not always reflect accurately upon either the behavioral episode itself or the treatment interventions most appropriate for preventing drug-related mortality.” These findings are important in part because if suicidal motivation underlies an important number of opioid overdoses, our approach to education, prevention, and treatment of OUD patients needs to change. This McLean Hospital team did very important work here: previous research on heroin use disorders showed low suicidal intention during overdoses, but did not gauge the spectrum of suicidal motivation. This research extends theoretical, though thought-provoking, work done previously by Volkow and O’Quendo, and by myself and Dr. A. Benjamin Srivastava.

This study says, for example, that efforts to help patients, from curbing prescriptions to expanding access to health care and effective medications, might not do anything to address suicidal motivation. Where is the psychiatrist, psychologist, and mental health expert in the evaluation of patients who have been rescued with naloxone or enter programs for medication assisted treatment?  Often, patients do not have a psychiatric consultation in the hospital or emergency department, or an evaluation for co-morbid depression, anxiety disorders, or trauma. Better screening standards and techniques, and more effective and targeted versions, could help health care providers more accurately assess the range of challenges patients face, and develop a better recognition of the kinds of treatment options that may be required in different situations. Screening standards specifically targeting suicidal motivation in OUD patients could save lives and improve outcomes. But the idea would be to evaluate patients earlier and not wait until they are actively suicidal.

This study is important because there is very limited actual data on depression, suicidality, and overdoses, and this study starts to fill the gap. But it also has a small sample size and relies on self-reporting measurements. It did not gauge support systems for patients or their exposure to adverse childhood experiences. And it’s limited by the demographics of its participants.

More research is necessary to determine the links between suicidal motivation and opioid overdoses and the effectiveness of efforts to stop suicide. At the same time, there’s a substantial amount of research drawing attention to connections between suicidal motivation and overdoses. In my own work, I’ve pointed to data suggesting that some number of opioid overdoses are better thought of as suicide attempts and that the total number may be larger than imagined. This study may be limited, but it is still providing legitimate quantitative data about suicidal motivation. I think Mayo Clinic’s Tyler Oesterle’s advice7 to evaluate for medical, infectious, psychiatric and other comorbidities is important, and that it’s supported by this study. 20-30 percent of individuals with OUD say that they have previously attempted suicide and “unintentional” overdose,8 and we know that those surviving overdoses face a heightened risk of suicide. This study also notes that there are several associations between overdoses and suicidal behavior in individuals with OUD, including a history of injection, polysubstance use, sexual or physical trauma, heroin use, and pain, among other correlates.

It’s difficult to tease out the contributions of trauma or depression and anhedonia to an overdose, and even harder to know what it all means for public health policy and responses to the opioid overdose epidemic. It seems obvious that individuals with OUD who die of fentanyl overdoses are often not deliberately even seeking fentanyl, let alone death. But it is important to look to actual data. These new data are actual finding, not conjecture. If focusing on depression, anhedonia, and despair can help save the lives of some patients, it’s worth paying much more attention to suicidal motivation. It’s also interesting that this study finds some OUD patients reporting a strong desire to die before their most recent overdose without believing that they were likely to overdose. Drugs of abuse cause structural changes to the very brain systems that we rely upon to estimate risk. This study points out that use may compromise self-assessment of dangers, leaving some patients in jeopardy after they did not realize the life and death risk they were exposing exposed to. Better prevention and education initiatives could help here, not just by trying to stop suicide, but by helping patients realize the genuine risks of their attitudes and behaviors. Rather than assuming that all overdoses are “accidental,” it is time to consider reversing the burden of proof by considering them suicide attempts, as my colleague Dr. David A Patterson Silver Wolf has recently suggested.