The Link Between Substance Abuse, Violence, and Suicide
Suicide is the 11th leading cause of death in the United States; it accounts for more than 34,000 deaths per year. 1 And an even greater number of people attempt suicide. Based on data from community surveys, approximately 5% of adults have made a serious suicide attempt. 2
Mental health problems are some of the best-known and well-studied risk factors linked to suicidal ideation, suicide attempts, and suicide mortality. Approximately 90% of all individuals who completed suicide met criteria for 1 or more diagnosable psychiatric conditions. Mental health conditions most strongly associated with fatal and nonfatal suicide attempts include depression, bipolar disorder, schizophrenia, posttraumatic stress disorder, and alcohol and/or drug use disorders. 2-4 Because mental health treatment providers are in regular contact with patients at risk for suicide, they are an important resource for early detection and prevention of suicidal behavior.
Substance use and suicide risk
Although it is difficult to compare the relative impact among different mental health problems with the risk of suicide, alcohol and drug use disorders have been found to be strongly related to suicide risk. 3,5 Individuals with a substance use disorder (ie, either a diagnosis of abuse or dependence on alcohol or drugs) are almost 6 times more likely to report a lifetime suicide attempt than those without a substance use disorder. 2 Numerous studies of individuals in drug and alcohol treatment show that past suicide attempts and current suicidal thoughts are common. 6-8 Recent evidence from veterans indicates that men with a substance use disorder are approximately 2.3 times more likely to die by suicide than those who are not substance abusers. Among women, a substance use disorder increases the risk of suicide 6.5-fold. 9
Identifying substance abusers at greatest risk for suicide
Although a consistent association exists between substance use disorders and suicidal behaviors, the vast majority of those with substance-related problems will never die by suicide. Therefore, it is important to identify those individuals with substance use disorders who might be at particularly high risk for suicide.
Many risk factors for suicide in the general population also apply to those with substance use disorders. Older men with substance use disorders are at greater risk for nonfatal attempts and for death by suicide than are younger persons. 10,11 Past suicide attempts are a strong risk factor for subsequent suicidal behaviors in those with substance use disorders. 12 Depressed mood is a risk factor for suicidal behaviors in the general population and also predicts a greater likelihood of suicide in those with alcohol or drug use disorders. 3,6,10 The link between depression and suicidal behaviors in those with substance use disorders may be particularly strong given the high comorbidity between mood and substance use disorders. 13 Although it has not been examined thoroughly, independent mood disorders and substance-induced mood disorders are likely to confer risk for suicide.
Emerging research suggests that some individuals with particular types of substance use and abuse may be more likely to engage in suicidal behaviors. For example, individuals who use opiates, cocaine, and sedatives may have a noticeably higher risk of suicide than those who use other drugs. 12,14-16 Among those with an alcohol use disorder, a greater severity of recent drinking is associated with the greater likelihood of suicide attempt and suicide mortality. 17,18 Co-occurring alcohol and drug use disorders may be particularly strong indicators of increased risk of suicide. 19 Thus, the severity of substance use disorders (ie, a greater number of substances or misuse of more than 1 substance) may predict a greater likelihood of suicide.
Violent behavior toward others
The tendency to engage in violent behavior is a potentially important risk factor for suicide in substance abusers. Up to 75% of those who begin addiction treatment report having engaged in violent behavior (eg, physical assault, mugging, attacking others with a weapon). 20,21 Emerging research also indicates that violence may partially account for the connection between substance abuse and suicide risk. For example, in those seeking treatment for substance use disorders, the perception that they have difficulty in controlling their own violent behavior was associated with a greater likelihood of a prior suicide attempt. 22 Tiet and colleagues 22 hypothesized that individuals who have difficulty in controlling their anger may be more likely to act impulsively, thus turning the violence on themselves rather than on others.
Individuals with alcohol use disorders and prior aggressive behavior are more likely to report suicidal thoughts or past suicide attempts. 6,23 In one recent study of more than 6000 adults who began addictions treatment, those who had committed serious violent acts (eg, rape, murder, assault resulting in serious injury) were more than twice as likely to report multiple suicide attempts. This finding held true even after statistically controlling for demographic characteristics, depression, and past victimization. 6
Another study compared accident victims with individuals who completed suicide. Violent behavior in an individual’s last year of life was linked to a higher likelihood of suicide, even when controlling for alcohol use disorders and other potential suicide risk factors. 24
A growing body of literature has identified the link between substance use disorders, interpersonal violence, and risk of suicide.
This article reviews this literature and provides suggestions for how to identify substance use disorder patients who may be at elevated risk for suicide.
Mental health providers should be aware that individuals with substance use disorders are at elevated risk for suicide and should include questions about prior violence toward others as part of a comprehensive suicide risk assessment.