Examining the Relationships Among Opioid Use, Overdose, and Suicide

Opioid-related mortality in the United States has increased at an alarming rate during the last 2 decades as a result of both suicide and unintentional overdose, posing a major public health concern. The combined number of opioid-related suicides and overdoses almost tripled from 2000 to 2017 (going from 41,364 to 110,749).¹ Suicide and unintentional overdose have both been targets of large-scale prevention efforts (eg, with the National Strategy for Suicide Prevention and the State Targeted Response to the Opioid Crisis grant program of the Substance Abuse and Mental Health Services Administration).² In October 2018, President Trump announced that his administration was declaring the opioid crisis a national Public Health Emergency under federal law, and directing all executive agencies to “use every appropriate emergency authority to fight the opioid crisis.”³

A recent article examines the relationship between opioids and both forms of mortality: overdose and suicide.¹ Unlike the relationship between opioids and unintentional overdose, the connection between opioid use and suicide risk is unclear, and opioid use disorder is thought to be associated with suicide to a greater degree compared with other substance use disorders.

“Overdose and suicide have both increased in recent years in the US, unlike almost every other common cause of death,” lead author Amy Bohnert, PhD, associate professor at the University of Michigan, Ann Arbor, told Clinical Pain Advisor. “Overdose and suicide are typically considered 2 different problems. We wanted to bring attention to the ways in which they are related to one another and could be addressed by some of the same approaches. There are a number of fundamental causes of overdose and suicide that go through the path of opioids, including biological, health system factors, and population trends of supply and demand,” she added.

The Pain Connection

“This biologic mechanism is supported by epidemiologic data that have shown that chronic-pain diagnoses are linked to suicide, and these associations are only partially explained by co-occurring mental health conditions,” according to the review authors. Although pain is also associated with opioid overdose, it appears that the association between chronic pain and suicide is mediated by the quantity of opioids prescribed.

The Role of the Medical System

Since the early 2000s, attitudes toward pain management have shifted, with a focus on managing untreated pain. This concern has led to increased numbers of prescriptions (and dosages) of opioids. Although the connection between the increase in prescription opioids and overdoses was acknowledged as early as 2000, a connection between these drugs and suicide has taken more time to be recognized.

Intent Sometimes Unclear

One of the conceptual links between suicide and overdose suggests that intentional overdoses may be considered a form of suicide. However, “it is challenging to classify overdose events according to intent,” especially when those events are fatal, the authors note.

Moreover, the authors add, the “intentionality” of overdose may be “dimensional, rather than categorical, and both fatal and nonfatal events may not be fully intentional or unintentional.” In addition, patients may not be able to differentiate between an overdose that was a suicide attempt and an overdose that was unintentional, or may regard the perceived intent differently after surviving the overdose.

Shared Risk Factors

There are several important shared risk factors between suicide and overdose, Dr Bohnert noted. “Both suicide and overdose, particularly opioid-related overdoses, are higher in men than in women, with opioid use related to both, but in complicated ways,” she said. Suicide and unintentional overdose rates were approximately twice as high in men vs women in 2017.⁴ They were highest for people identifying as white or Native American and lowest among people who identified as black or Asian.⁴ They were also highest during midlife (41-64 years old) and lowest among older people (≥65 years). However, the authors point out, there were also several “notable divergences” between the 2 causes of death, with suicide rates remaining high for white men (≥65 years) and rates of unintentional overdoses declining dramatically after age 64 years. White women as well as black and Native American men and women had “notably” higher rates of unintentional overdose than of suicide during midlife. The authors caution that these differences “may reflect known racial biases in medical-examiner rulings.”

“Mental health conditions are common among those who die by overdose, and not just [by] suicide,” Dr Bohnert observed. Nearly all common mental conditions are associated with unintentional overdose, including overdoses of both illicit and prescription drugs.⁵ Substance use disorders are more strongly associated with unintentional overdoses, and other mental health conditions are more strongly associated with intentional overdose.⁶

The authors note that the risk for both suicide and overdose is likely to be highest among those with co-occurring mental health disorders. The risk is further increased by concurrent use of other medications and drugs, or of recreational drugs (eg, alcohol and cocaine), and use of benzodiazepines. However, concurrent use of antidepressants, which the authors describe as “a well-established treatment for suicidality,” can reduce the risk for drug overdose in patients with depression who were being treated with opioid analgesics.⁷

Assessing the Risk

“There are a couple of different options for ‘risk scores,’ which can help clinicians assess the risk for overdose and suicide,” Dr Bohnert noted. These can include electronic tools that calculate a specific patient’s level of risk for suicide, overdose, or both, based on data contained in electronic health records.^8-10 These may help identify individuals who could benefit from additional services.

Patients who have been identified as being at additional risk should have an in-depth assessment of behavioral risk factors and suicidal thoughts or plans, as well as previous suicide attempts and nonfatal overdoses.

“For individuals worrying about their own risk, using a self-administered assessment of opioid misuse, like the Current Opioid Misuse Measure, can help gain a sense of whether the way you are handling your opioids might be risky,” added Dr Bohnert. “Other things to look out for are using opioids around the same time as other substances like alcohol and benzodiazepines, feeling overly sleepy or like a ‘zombie,’ or finding that opioids have become a focus in life to the point where it is affecting other things.”

Shared Prevention Approaches

The review authors recommend several “potential prevention opportunities, based on these shared conceptual links.”

For counseling or psychotherapy delivered to at-risk individuals by mental health professionals, evidence supports the use of cognitive behavioral therapy and motivational interviewing in suicide prevention. General mental health counseling and psychotherapy may also reduce the risk for both suicide and unintentional overdose. Although addiction treatment and mental health centers are well-positioned to provide these treatments, other clinicians can also integrate these approaches into their primary care practices, especially as behavioral pain management interventions are associated with improvements in functional outcomes in patients with chronic pain. “It is plausible that improvements in pain-related domains through counseling could also reduce the risk of suicide,” the authors note.

Reducing opioid dosage is described by the authors as “a controversial strategy relevant for people who receive prescriptions for potentially risky medication regimens or who exhibit signs of opioid misuse.” The Centers for Disease Control and Prevention recommends against escalating dosages for new patients above 90 morphine milligram equivalents, a threshold that has also been interpreted as a goal for tapering efforts.¹¹

“To this end, clinicians should ask about their patients’ access to opioids, including past prescriptions and medications prescribed to others in the same home,” advise the review authors. It is unknown, however, whether tapering modifies the risk for suicide or overdose, the authors caution.

Naloxone has been shown to reduce opioid-related emergency department visits.¹² Ideally, naloxone will be provided to a person who lives with the patient at risk for overdose and may be helpful not only with unintentional overdose but also with reversing suicide attempts.

Medication-assisted therapy, which combines medication (methadone, buprenorphine-naloxone, or naltrexone) and counseling for opioid use disorders, has been shown to reduce mortality, and particularly overdose mortality. However, suicide and overdose still continue to occur, even when at-risk individuals are receiving these interventions. Risk is highest at treatment initiation or sudden discontinuation. “Prevention should involve addressing these critical transition periods,” the authors emphasize.

Unresolved Issues and Controversies

The authors note several areas that require more research. One outstanding question is whether opioid tapering may result in patients transitioning to heroin use or uncontrolled pain, thereby increasing suicidality. “I think there is certainly a lot of reason to believe that people who were prescribed opioids for a long time and then abruptly stopped without adequate support for either potential issues of substance abuse or pain would be at risk for transitioning to obtaining opioids from nonlegal sources,” Dr Bohnert observed. “I don’t think this has been well-studied, so it is difficult to quantify how often this may be happening.”

Another outstanding issue is the way in which the risks for overdose and suicide have been studied. The authors point out that most research into these risks has been based on data from medical claims or research, with “only moderate predictive value.” They suggest that a potential measure to improve risk detection could be the level of opioid misuse, using measures such as the Current Opioid Misuse Measure.¹³

Last, “both suicide and overdose continue to result in a substantial burden of deaths in the United States, despite many clinical initiatives and numerous changes in state and federal policy,” the authors state. This suggests that prevention efforts thus far have been insufficient or effective only in addressing harm related to prescription opioids, but not the “wave” of heroin use and use of illegal synthetic opioids. “Improving access to and the quality of treatment of mental health conditions, pain, and opioid use disorders, is likely to result in reductions in rates of both overdose and suicide,” Dr Bohnert concluded.

References

1. Bohnert ASB, Ilgen MA. Understanding links among opioid use, overdose, and suicide. N Engl J Med. 2019;380(1):71-79.

2. US Department of Health and Human Services, Office of the Surgeon General, National Action Alliance for Suicide Prevention. 2012 National strategy for suicide prevention: goals and objectives for action. A report of the U.S. Surgeon General and the National Action Alliance for Suicide Prevention. Washington, DC: Department of Health and Human Services, September 2012 .

3. The White House. The opioid crisis. Available at: https://www.whitehouse.gov/opioids/. Accessed: December 18, 2018.

4. Centers for Disease Control and Prevention. Wide-ranging Online Data for Epidemiologic Research (WONDER), 2018. Available at: https://wonder.cdc.gov. Accessed: January 16, 2019.

5. Bohnert AS, Ilgen MA, Ignacio RV, McCarthy JF, Valenstein M, Blow FC. Risk of death from accidental overdose associated with psychiatric and substance use disorders. Am J Psychiatry 2012;169(1):64-70.

6. Bohnert AS, McCarthy JF, Ignacio RV, Ilgen MA, Eisenberg A, Blow FC. Misclassification of suicide deaths: examining the psychiatric history of overdose decedents. Inj Prev. 2013;19(5):326-330.

7. Turner BJ, Liang Y. Drug Overdose in a retrospective cohort with non-cancer pain treated with opioids, antidepressants, and/or sedative-hypnotics: interactions with mental health disorders. J Gen Intern Med. 2015;30(8):1081-1096.

8. Oliva EM, Bowe T, Tavakoli S, et al. Development and applications of the Veterans Health Administration’s Stratification tool for Opioid Risk Mitigation (STORM) to improve opioid safety and prevent overdose and suicide. Psychol Serv 2017;14(1):34-49.

9. Glanz JM, Narwaney KJ, Mueller SR, Gardner EM, Calcaterra SL, et al. Prediction model for two-year risk of opioid overdose among patients prescribed chronic opioid therapy. J Gen Intern Med. 2018;33(10):1646-1653.

10. Simon GE, Johnson E, Lawrence JM, Rossom RC, Ahmedani B, Lynch FL, et al. Predicting suicide attempts and suicide deaths following outpatient visits using electronic health records. Am J Psychiatry. 2018;175(10):951-960.

11. Dowell D, Haegerich TM, Chou R. CDC guideline for prescribing opioids for chronic pain–United States, 2016. JAMA. 2016 Apr 19;315(15):1624-1645.

12. Coffin PO, Behar E, Rowe C, et al. Nonrandomized intervention study of naloxone coprescription for primary care patients receiving long-term opioid therapy for pain. Ann Intern Med. 2016;165(4):245-252.

13. Butler SF, Budman SH, Fernandez KC, et al. Development and validation of the Current Opioid Misuse Measure. Pain. 2007;130(1-2):144-156.