Acute stressors and clinical characteristics differentiate death by suicide, accident, or natural causes among illicit and prescription opiate users

Highlights

• Compared opioid users who died by natural cases, accidents, and suicide.

• Substance use and suicide risk were evaluated using psychological autopsy methods.

• Suicide completer sample significant for depression and previous suicide attempt.

• Accidental overdose sample significant for a chronic pattern of severe drug abuse.

Abstract

Background

Opiate misuse has reached epidemic levels. Prevention efforts depend on distinguishing opiate users from abusers. The current study compared opioid users who died by natural cases, accidents, and suicide using psychological autopsy methods. Groups were compared on substance use characteristics, treatment history, experiences of negative life events, and circumstances at the time of death.

Methods

Substance use and suicide risk were evaluated using psychological autopsy methods in 63 decedents with positive toxicology for opiates at death divided into three groups: adults dying by suicide (n = 19), accident (n = 19), and natural causes (n = 25). Groups were compared on several dependent measures, using chi-square analyses to examine categorical variables and one-way analyses of variance (ANOVA) to examine continuous variables.

Results

Individuals who died by suicide were similar in many ways to adults who died by an accidental overdose. However, suicide completers were more likely to have struggled with severe depression, and previously attempted suicide, whereas the accidental overdose sample was more likely to display a chronic pattern of severe drug abuse.

Conclusions

The current study helps to distinguish between opiate users who are at risk for death by an accidental or intentional overdose. In the ongoing opiate crisis, clinicians must understand the risk of overdose and the nuances of accidental behaviors compared to purposeful ones. Signs of suicidal planning, relevant psychopathology, and ongoing life stress may be useful points of intervention for stopping the increasing number of deaths among opiate users.

Introduction

Prescription (Calcaterra et al., 2013; Cerdá et al., 2013) and illicit (Calcaterra et al., 2013; Cerdá et al., 2013) opioid use is on the rise internationally. As many as 11.8 million Americans over the age of 12 misuse any form of opiates, with the majority misusing prescription opiates (N = 10.9 million; (Bose et al., 2018). Heroin (Lopez-Quintero et al., 2015), other intravenous drug use (Artenie et al., 2015), and polysubstance misuse and dependence (Artenie et al., 2015) have consistently been identified as risk factors for accidental and suicidal overdose. Recent research indicates that prescription opioid use is also associated with premature mortality due to accidental overdose (Calcaterra et al., 2013) and suicide (Austin et al., 2017). Opiate users die prematurely from any cause, natural causes, accidents, and suicide (Pierce et al., 2015).

The initial use of opiate medication is often initiated by the presence of chronic pain. Chronic pain and depression are often related and when both problems occur, substance abuse is common (Madadi and Persaud, 2014). In the 12 months following a nonfatal opioid overdose, there is a significantly elevated risk of dying from a variety of medical problems (Olfson et al., 2018). Furthermore, there is an important connection between opiate use and suicide. In a national survey of more than 41,000 adults across the US, the abuse of prescription opiate medication has been found to be associated with suicidal ideation, suicide planning, and suicide attempts (Ashrafioun et al., 2017). Furthermore, in recent years, opioid use has become more frequently noted in the toxicology results of individual who die by suicide (Braden et al., 2017). Among opiate users, intentional and accidental overdose are distinct events (Bohnert and Ilgen, 2019; Britton et al., 2012). Distinguishing factors may include the presence of depression, anxiety, or personality pathology (Maloney et al., 2009). High levels of opiate use are related to increased risk of suicide, not limited to intentional drug overdose (Ilgen et al., 2016). It has been estimated that 20–30 % of deaths by opioid overdose are best classified as suicides (Oquendo and Volkow, 2018).

Prevention efforts depend on identifying which opiate users are at risk of dying by medical complications, accidental overdose, or suicide. Identifying a profile of risk for premature death in high-risk populations like opiate users may be difficult. There are some indications that accidental opiate overdoses and suicide by opiate overdose have been misclassified in recent epidemiologically-based research (Rockett et al., 2018). Epidemiological research can only offer clues about national level risk-factors for opioid-related mortality if medical examiners are able to correctly classify the manner of death in national death reporting surveillance systems. Research evaluating suicide decedents is limited (Ribeiro et al., 2018) and little is known about factors which differentiate individuals who die by suicide from those who die by accidental overdose.

Clinical (Hakansson and Gerle, 2018) and forensic (Stone et al., 2017) psychologists have called for the use of psychological autopsy evaluations of premature deaths among opioid users. Post-mortem research has evaluated large, nationally or regionally representative databases containing information about decedents with opioid use disorders or opioid prescriptions. Differentiating accidental overdoses from suicide by overdose may be complicated in post-mortem research (Rockett et al., 2018) when information about suicidal intent is limited. Psychological autopsy methodologies may enhance population-wide analyses because they integrate autopsy reports, police death scene investigations, medical and psychiatric record review, and interviews with decedents’ family members. While psychological autopsy studies cannot account for decedents’ subjective experience, validated post-mortem methodologies can be used to characterize decedents’ functioning prior to death and evaluate manner of death (Conner et al., 2011; Connor et al., 2012).

By definition, suicidal intent differentiates deaths by intentional overdose from deaths by accidental overdose. Opioid use disorders and prescription opioid misuse are independently associated with an increased risk of suicidal ideation, planning, and attempts when adjusting for physical and mental health conditions (Ashrafioun et al., 2017). Suicidal intent may be a continuous, multi-faceted, or dynamic construct. Most subjects reported ambivalence about suicidal intent following an opioid overdose (Neale, 2000). Illicit drug use is significantly related to non-fatal suicide attempts but not suicidal ideation in multivariate analyses controlling for psychiatric diagnoses (Ashrafioun et al., 2015). Thus, it is possible that individuals who die by accidental and intentional overdose cannot be categorized based on evidence of suicidal ideation or suicidal intent prior to death.

The primary aim of the present study was to extend the post-mortem opioid literature by using psychological autopsy research to compare opioid users who died by natural causes, accidents, and suicide. We compared subjects on characteristics which have been shown to increase risk of morbidity or mortality in nationally representative studies of decedents. Specifically, we evaluated between-group differences in demographic background, clinical and substance use characteristics, and treatment history. We also compared subjects’ experiences of negative life events leading up to death. This study assessed circumstances at the time of death which differentiate risk of death by accident, suicide, or natural causes among opiate users. We evaluated whether opioid users who died by suicide or accident showed differences in beliefs about death, preparation for life-threatening behaviors or death, suicidal ideation, suicidal intent, or suicidal planning. It was predicted that cases of death by suicide would be related to prominent symptoms of depression and more severe life stress.

Our analyses focused on opioid users who had positive opioid toxicology screens at the time of death, rather than individuals who were diagnosed with opioid use disorders prior to death, since a range of opioid misuse may increase mortality (Ilgen et al., 2016). Nationally representative studies indicate that both opioid use disorders (Pierce et al., 2015) and opioid misuse (Ashrafioun et al., 2017) are associated with significant increases in risk for premature death and other high-risk behaviors (Mojtabai, 2018). Focusing research on individuals who suffer from opiate use disorders may underestimate the effects of opiates on premature mortality.