On prediction, refutation, and explanatory reach: A consideration of the Interpersonal Theory of Suicidal Behavior

Ethological Problems with the Interpersonal Theory of Suicide

Joiner and colleagues' Interpersonal Theory of Suicide (IPTS), a prominent "desire-capability" model of suicide-based on the common-sense idea that people take their own lives because they want to, and can-is critiqued from a biological perspective. Tinbergen's ethological "four questions" guide the analysis: evolution, survival value, ontogeny, and proximate causation, each addressing a different aspect of biological understanding. Problems for IPTS emerge with all four. As a parsimonious solution, the desire-capability hypothesis is reconceived as an ultimate, instead of proximate, mode of explanation. By this light, desire and capability for suicide combined in our species' ancestral past, thus making suicide a recurrent survival threat, and driving the evolution of special-purpose defensive adaptations. This stance tallies with the pain-brain theory of the evolution of suicide, and with Joiner and colleagues' own investigation into organismic anti-suicide defenses, which appears to conflict conceptually with IPTS. These defenses' evolved algorithm may make suicide an intrinsically aleatory phenomenon, opaque to usefully accurate prediction. Positive implications for prevention and research are proposed.

A Prospective Examination of the Interpersonal-Psychological Theory of Suicidal Behavior in Adolescents

OBJECTIVE

Given the large and complex array of suicide risk factors, theoretical frameworks are critical to furthering our understanding of risk. This study prospectively examined several key constructs of the interpersonal-psychological theory of suicidal behavior (IPTS) in a large, geographically diverse sample of U.S. adolescents.

METHOD

Conducted in collaboration with the Pediatric Emergency Care Applied Research Network, adolescents, ages 12 to 17, were recruited from emergency departments. Baseline and 6-month follow-up samples were comprised of 6,448 (59% female sex) and 2,009 (64% female sex) adolescents, with self-identified race/ethnicity as follows (baseline/follow-up): White (52%/54%), Black (22%/23%), Multiracial (6%/6%), American Indian (3%/3%), other/unknown race (15%/14%), and Latinx (25%/23%). Youth and parents completed adolescent suicide risk surveys at baseline and 6-month follow-up (retention, 69%). Latent class analysis was used to identify classes of painful and provocative events (PPE), considered a precursor to acquired capability.

RESULTS

In keeping with IPTS tenets, thwarted belongingness (TB), perceived burdensomeness (PB), and the interaction between TB and PB were each significant predictors of suicidal ideation at baseline and follow-up. However, only PB and PPE were significant predictors of cross-sectional suicide attempts and only TB and PPE were significant predictors of prospective suicide attempts in models that adjusted for baseline suicidal ideation. The three-way interaction among PB, TB and PPE was nonsignificant.

CONCLUSIONS

Results from this large-scale prospective study suggest the importance of TB, PB, and PPE to our understanding of suicidal thoughts and suicide attempts among adolescents, pointing to promising prevention and intervention targets.

A Psychometric Evaluation of the Interpersonal Hopelessness Scale Among Individuals With Elevated Suicide Risk

The interpersonal theory of suicide hypothesizes that suicide ideation (SI) emerges specifically in the context of hopelessness about the immutability of thwarted belongingness (TB) and perceived burdensomeness (PB; i.e., interpersonal hopelessness). The psychometrics of the Interpersonal Hopelessness Scale (IHS), which could be used to test this hypothesis directly, have not been rigorously evaluated. Participants (U.S. adults reporting past-year SI) completed online self-report assessments at Waves 1 (W1; N = 595) and 2 (W2; N = 215), 1 week apart. Confirmatory factor analyses supported a two-factor structure, IHS-TB and IHS-PB. Correlations indicated strong concurrent validity. Hurdle negative binomial regressions indicated that W1 IHS-TB and IHS-PB scores were associated with SI presence and severity at both waves, but this was inconsistent when adjusting for other W1 variables. IHS-TB and IHS-PB demonstrated excellent internal consistency and moderate to good test-retest reliability. The IHS could improve theory testing and suicide risk assessment and management.

Examination of real-time variation in interpersonal hopelessness and suicidal desire in a college student sample reporting past-2-week suicidal ideation

INTRODUCTION

Interpersonal hopelessness (IH), as outlined in the Interpersonal Theory of Suicide, is theorized to include two correlated, distinct constructs: hopelessness about one's thwarted belongingness (IH-TB) and about perceived burdensomeness on others (IH-PB). Few studies have explored IH, and none have explored its temporal stability or prospective prediction of suicidal desire.

METHODS

Undergraduates (N = 43) selectively recruited for past-2-week suicidal ideation completed five ecological momentary assessment surveys per day for 10-days. Intraclass correlations, root mean square of successive differences, and multilevel models were used to examine the data and test relationships among predictor variables.

RESULTS

IH-TB and IH-PB demonstrated greater temporal stability than general hopelessness. IH-TB, IH-PB, and their interaction were significant predictors of suicidal desire concurrently and prospectively. IH-PB was no longer significantly predictive of suicidal desire when adjusting for general hopelessness. Post-hoc models showed that suicidal desire was not predictive of IH-TB, IH-PB, or their interaction suggesting the relationship is not recursive.

CONCLUSION

Results showed that interventions aimed at decreasing one's hopelessness specific to TB and PB may be beneficial for decreasing suicidal desire. Future research should seek to replicate these results in larger and more diverse samples and consider the use of shorter ambulatory assessment intervals.

Targeting Perceived Burdensomeness to Reduce Suicide Risk

Perceived burdensomeness (PB), defined by an intractable perception of burdening others, often reflects a false mental calculation that one's death is worth more than one's life and has been supported as a significant risk factor for suicide. Because PB often reflects a distorted cognition, it may serve as a corrective and promising target for the intervention of suicide. More work on PB is needed in clinically severe and in military populations. Sixty-nine (Study 1) and 181 (Study 2) military participants at high baseline suicide risk engaged in interventions targeting constructs relating to PB. Baseline and follow-up measures (at 1, 6, 12, 18, and 24 months) of suicidal ideation were administered, and various statistical approaches-including repeated-measures ANOVA, mediation analyses, and correlating standardized residuals-explored whether suicidal ideation decreased specifically by way of PB. In addition to utilizing a larger sample size, Study 2 included an active PB-intervention arm (N = 181) and a control arm (N = 121), who received robust care as usual. In both studies, participants improved considerably regarding baseline to follow-up suicidal ideation. The results of Study 2 mirrored those of Study 1, corroborating a potential mediational role for PB in treatment-related improvements in suicidal ideation in military participants. Effect sizes ranged from .07-.25. Interventions tailored at decreasing levels of perceived burdensomeness may be uniquely and significantly effective in reducing suicidal thoughts.

An Integrated Conceptual Model to Understand Suicidality among Queer Youth to Inform Suicide Prevention

In this article, we apply and combine elements from four theoretical frameworks (i.e., Minority Stress Theory, Person-in-Environment and Risk and Resilience Framework, Interpersonal-Psychological Theory of Suicide, and Intersectionality) to explain the problem of queer youth suicide through our integrated conceptual model, Queer Prevention of Youth Suicidality Model (Queer-PRYSM). The need for this conceptual model is based on the current state of the literature, including mixed empirical findings on factors related to queer youth suicidality, no scholarly consensus on specific contributing factors regarding high rates of suicidality among queer youth (including queer youth subgroups), and the absence of a unifying theory to explain the queer youth suicide risk. To address these limitations in theory, evidence, and scholarship explaining suicidality among queer youth we present our integrated model with growing, current, relevant research with queer youth. Queer-PRYSM includes minority stressors specific to queer youth, mental health problems, interpersonal-psychological factors, socioecological factors (i.e., family, school, peers, and community), and intersectionality concepts. Queer-PRYSM is essential to understanding the relationship of distal and proximal risk and protective factors in queer youth suicide and developing evidence-informed suicide preventive interventions that can be incorporated into practice, policy, and system structures.

Non-suicidal self-injury and its relation to suicide through acquired capability: investigating this causal mechanism in a mainly late-diagnosed autistic sample

BACKGROUND

Non-suicidal self-injury (NSSI) has been linked with a higher risk of suicide attempts in autistic and non-autistic people. In the general population, NSSI may confer acquired capability for suicide by eroding one's fear and avoidance of pain and death. The present study aimed to explore acquired capability as the mediator of increased suicide risk conferred by NSSI in autistic and non-autistic adults.

METHODS

Autistic and non-autistic adults (n = 314, n = 312) completed an online survey exploring lifetime suicide attempts, experience with NSSI, and acquired capability for suicide. We explored relationships between lifetime incidence of NSSI and lifetime suicide attempts via three facets of acquired capability (pain tolerance, reduced fear of death, and mental rehearsal of suicide). In self-harming participants (224 autistic and 156 non-autistic), we explored whether particular types and features of NSSI might be especially associated with capability and through that with suicide: namely engagement in scratching, cutting, and self-hitting, and engaging in more numerous forms of NSSI.

RESULTS

While a higher frequency of NSSI was associated with all three facets of acquired capability, only reduced fear of death and mental rehearsal of suicide mediated an indirect relationship with lifetime suicide attempts. NSSI also directly predicted more numerous suicide attempts. Autistic people tended towards reduced fear of death and mental rehearsal regardless of NSSI status. Among self-harming autistic and non-autistic participants, cutting and an increased number of NSSI behaviours were associated with lifetime suicide attempts directly and indirectly via acquired capability. In both groups, self-hitting was associated with lifetime suicide attempts only via acquired capability.

LIMITATIONS

Our cross-sectional methodology negates inferences of directionality. While we controlled for age, our samples were poorly matched, with the autistic group two times older on average. The autistic sample, predominantly late-diagnosed, female and highly qualified, were unrepresentative of the whole autistic community.

CONCLUSIONS

Our data suggest that acquired capability, as measured herein, is an incomplete explanation for the association between NSSI and suicide risk. A broader construct with stable and transient facets may offer greater explanatory power, but it is probable that other variables explain or provide additional means through which this association arises.

Assessing Prevalence and Unique Risk Factors of Suicidal Ideation among First-Year University Students in China Using a Unique Multidimensional University Personality Inventor

BACKGROUND

University students with suicidal ideation are at high risk of suicide, which constitutes a significant social and public health problem in China. However, little is known about the prevalence and associated risk factors of suicidal ideation among first-year university students in China, especially during the COVID-19 pandemic.

OBJECTIVES

To investigate the prevalence of suicidal ideation and its factors in first-year Chinese university students from a vocational college in Zhejiang during the COVID-19 pandemic.

METHODS

Using a cluster sampling technique, a university-wide survey was conducted of 686 first-year university students from Hangzhou in March 2020 using University Personality Inventory (UPI). UPI includes an assessment for suicidal ideation and possible risk factors. Suicidal ideation prevalence was calculated for males and females. Univariate analysis and multivariable logistic regression models were conducted, adjusting for age and sex. Analyses were carried out using the SPSS version 22.0 software.

RESULTS

The prevalence of 12-month suicidal ideation among first-year university students during March 2020 was 5.2%, and there was no significant difference between males and females (4.8% vs. 6.0%, x2 = 0.28, p = 0.597). Multivariable logistic regression analysis identified social avoidance (B = 0.78, OR = 2.17, p < 0.001) and emotional vulnerability (B = 0.71, OR = 2.02, p < 0.001) as positively associated with suicidal ideation.

CONCLUSIONS

Social avoidance and emotional vulnerabilities are unique factors associated with greater suicidal ideation among first-year university students during the COVID-19 pandemic. UPI serves as a validated tool to screen suicide risks among Chinese university students. Encouraging social engagement and improving emotional regulation skills are promising targets to reduce suicidal ideation among first-year university students.

Newtonian science, complexity science and suicide-critically analysing the philosophical basis for suicide research: A discussion paper

AIM

A critical discussion comparing Newtonian science and complexity science as the philosophical basis for suicide research and its impact on suicide knowledge development and clinical practice.

DESIGN

Discussion paper.

DATA SOURCES

A review of literature on suicide research and complexity science ranging from 2000 to 2022.

IMPLICATIONS FOR NURSING

Suicide research based on a Newtonian worldview can have negative consequences for suicide knowledge development and can permeate nursing practice in ways that take away from addressing the complex needs of patients, their families and healthcare teams.

CONCLUSION

A Newtonian worldview as a philosophical basis for research is insufficient for the study of a phenomenon as complex as suicide. A complexity science approach is better suited to the study of suicide given the multiple, interrelated, emerging factors that can contribute to a person's decision to end their own life.

IMPACT

Suggestions are provided as to how a complexity science approach to the research of suicide can inform useful knowledge development that better meets the needs of individuals facing suicidality and their families. Researchers, healthcare administrators and nurses providing care to those struggling with suicidality can benefit from adopting a complexity science worldview in addressing this multifaceted phenomenon.