Although other studies have reported significant associations between negative interpersonal events and suicidal behaviors in a PD sample (Heikkinen et al., 1997
), to our knowledge the present study is the first to find this association with a prospective design and time-varying analyses. Our study design and statistical analyses enabled us to determine that specific events (i.e., negative events pertaining to love–marriage and crime–legal matters) carry imminent risk for a suicide attempt in the month of, or the month following, the onset of the event. This was a robust finding that remained even after controlling for numerous other risk factors for suicidal behavior (i.e., baseline diagnoses of BPD, MDD, substance use disorders, and childhood sexual abuse). Unlike other studies that were based on psychological autopsies or inpatients hospitalized for a suicide attempt, our sample was not selected on the basis of past suicidal behaviors. Given the high rate of fatalities in first suicide attempts, examining suicide attempts in a sample broader than those who have made previous attempts provides a valuable perspective. Furthermore, the relative rarity of suicide and suicide attempts in contrast to the relatively higher rates of psychiatric diagnoses strengthens the clinical relevance of our findings.
Most of our findings are concordant with other empirical investigations. Our finding that negative, but not positive, life events were significantly associated with suicide attempts is consistent with other prospective studies that have examined life events as predictors of depressive episodes (Friis, Wittchen, Pfister, & Lieb, 2002
; Mundt, Reck, Backenstrass, Kronmuller, & Fiedler, 2000
). Despite the robustness of the love–marriage event category as being a significant predictor of suicide attempts, no particular event in this category stood out as being significantly associated with suicide attempts. This is most likely a result of the relatively small cell sizes in each of these event categories. However, it may be that the way in which an event affects an individual is more meaningful than the occurrence of such an event. For example, seemingly negative events such as divorce can have positive emotional consequences for some people. In some circumstances, such events can even improve emotional well-being (Gunderson et al., 2003
). In a recent study of stressful life events in which events were rated on dimensions of loss, humiliation, entrapment, and danger, high ratings of loss and humiliation were found to predict onsets of major depression and mixed depression–anxiety (Kendler, Hettema, Butera, Gardner, & Prescott, 2003
). It seems likely that many negative events related to love and marriage do involve either loss or humiliation but that making predictions on the basis of specific events (e.g., ending a relationship, divorce) entails greater details about the circumstances surrounding the event and the emotional sequelae of the event.
In contrast to the love–marriage event category, analyses of specific types of crime–legal events determined that some specific events were associated with a significant risk factor, whereas others were not. These included being a victim of a physical attack–assault, being accused of a crime, being arrested, being sent to jail, and being involved in a court case. The higher frequency of these events compared with the love–marriage events may partially explain why specific crime–legal events were found to be predictive of suicide attempts. However, it is telling that such high frequencies of crime–legal related events, both as victim and perpetrator, were observed in our sample. One possible explanation is that certain types of crime–legal life events are internally generated by personality characteristics. The events that were significant are not independent of certain PD traits, particularly those of Cluster B PDs. For example, PD traits such as impulsivity and aggression can increase the chances of being the victim of a physical assault, being accused of a crime, being arrested, being sent to jail, and being involved in a court case. These same traits have been related to increased risk for suicidal behaviors. However, the relationship between these variables and whether crime–legal events mediate the relationship between impulsivity–aggression and suicidal behaviors, to the best of our knowledge, is uninvestigated.
Regardless of whether one is the victim or perpetrator, crime–legal events can also lead to feelings of loss, humiliation, and other emotionally vulnerable outcomes, though presumably how these events are cognitively and emotionally processed would be different. In addition, these events seem more likely to generate similar emotional responses within a specific event than the love–marriage events. Most individuals experiencing crime–legal experiences (particularly as perpetrator) have a greater degree of personal contribution to the event, whereas events relating to love–marriage almost invariably involve shared contributions. Even the event of an unprovoked physical attack or assault is likely to generate more universal emotions or experiences (e.g., feelings of violation and injustice, humiliation) than most love–marriage events (with the possible exception of the death of a loved one). This suggests the importance of a relational-cognitive-orientation approach that emphasizes the meaning attributed to the event and the subjective impact of the event (Lazarus, Delongis, Folkman, & Gruen, 1985
The question of whether life events are predictive of suicidal behavior among those with more severe psychiatric disturbance is not easily addressed by our data because all participants had a baseline diagnosis of a PD and most had other additional diagnoses. Our analyses to determine whether there was a significant interaction effect between baseline global functioning (which is a proximate measure of psychopathology and overall psychosocial functioning) and life event category were not significant, suggesting that the degree of psychopathology–functioning does not affect the extent to which life events predict subsequent suicide attempts. Furthermore, our data suggest that even among those with severe psychiatric disturbance, life events can predict suicide attempts. Despite studies that have questioned the impact of life events on suicidal behaviors in severe psychiatric populations, our findings strongly support the importance of considering recent life events in evaluating suicide risk among those with PDs.
The strength of the present study is the prospective design and the documentation that the life event under investigation preceded the suicide attempt. However, our analyses of life events that predicted suicidal behavior were necessarily based on retrospective reporting because of our hypothesized time-varying association (i.e., that life events would be an imminent risk factor). Most studies of suicide attempts have been mainly retrospective and correlational, thereby precluding inferences of a causal relationship. The results of the present study clearly suggest that negative life events are significantly associated with suicide attempts and that individuals experiencing events relating to love–marriage are 3 times more likely to make a subsequent suicide attempt within the next 1–2 months compared with those who have not experienced a negative love–marriage event. Furthermore, those who reported crime–legal events are 2.5 times more likely to make a suicide attempt compared with those who have not had such experiences.
There are several limitations to the present study. As previously mentioned, the same life event may bring about different emotional consequences depending on the circumstances. This is particularly notable with regard to love and marriage related events. The instrument used in this study did not assess participants’ subjective experiences of each of their significant life events, and this lack of distinction may have obscured some of our findings. The determination of positive and negative events was not instrument based but rather was made by a team of three investigators within the present study who agreed by a conservative consensus on what constituted a positive event. Although potentially problematic for reasons cited above, leaving in the positive events (e.g., promoted, married, birth of child) along with the negative events within any given life event category could have neutralized our findings. Finally, we did not assess daily hassles or chronic stress, experiences that can also predict suicidal behaviors. As with all life events research, the timing of events reported was solely based on the participants’ memory and recall. Clearly, methods to assess the valence or context of life events need further development.
Pathways that link stressful life events and suicidal behaviors most likely include mediating and moderating variables. Many have speculated that the relationship between life events and negative outcomes, including suicidal behaviors and onsets–relapses of Axis I disorders, follows a diathesis stress model in which the individual has a preexisting vulnerability that becomes activated when his or her threshold for stressful events becomes breached. For most individuals, negative stressful life events occur repeatedly over one’s lifetime but do not generally elicit extreme responses such as suicidal behaviors. When this occurs, it is most likely because of individual vulnerabilities or repeated events that push people beyond a certain threshold. Future longitudinal studies are needed to examine the process by which life events affect suicidal behavior and should examine cognitive and psychological processes that shape how an event is appraised and how individuals cope or respond to such events.