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. Author manuscript; available in PMC: 2023 Jan 1.
Published in final edited form as: Aggress Behav. 2021 Nov 1;48(1):75–84. doi: 10.1002/ab.22003

The Moderating Role of Pessimism in the Association between Retrospective Relational Peer Victimization, Interpersonal Risk Factors, and Suicide Ideation

Nikki L La Rosa 1, Sarah L Brown 1,2, Sean M Mitchell 1,3, Paige L Seegan 4, Kelly C Cukrowicz 5
PMCID: PMC8678312  NIHMSID: NIHMS1750137  PMID: 34724225

Abstract

Peer victimization (PV) is a serious concern for youth and is associated with subsequent suicide ideation in young adulthood. The interpersonal theory of suicide may provide a framework for understanding suicide ideation in this population. Specifically, thwarted belongingness (TB) and perceived burdensomeness (PB) have been significantly associated with suicide ideation among young adults with a history of peer vicrimiztion. Additionally, the personality trait of pessimism is associated with elevated suicide ideation. Thus, this study tested the association between self-reported frequency of retrospective relational (i.e., verbal and indirect) PV in primary and secondary school, thwarted interpersonal needs (TB and PB), and current suicide ideation, as well as how these relations may vary based on current pessimism. Participants were 330 undergraduate students. Non-parametric bootstrap moderated mediation procedures were used to test hypotheses. Results indicated significant indirect effects of frequency of retrospective relational PV and suicide ideation through PB and TB. Contrary to predictions, results did not indicate significant moderated mediation; however, the association between PB and suicide ideation was stronger at lower pessimism levels. We also provide supplemental analysis with optimism as the moderator. These findings suggest that clinicians may consider targeting TB, PB, as well as pessimism and optimism among those with a history of relational PV when assessing and intervening on current suicide ideation. Implications, limitations, and future directions are further discussed.

Keywords: peer victimization, interpersonal theory of suicide, thwarted belonging, perceived burden, pessimism, suicide ideation

Suicide rates continue to increase annually, posing a crucial public health problem (Centers for Disease Control and Prevention [CDC], 2021). In fact, suicide is the second leading cause of death for young adults ages 18 to 24 in the United States (CDC, 2021), and in 2018, the 12-month prevalence of suicide ideation among college students was 10.6% (Mortier et al., 2018). College students may be a distinct young adult population given research suggests they are specifically at elevated risk for suicide ideation, attempts, and deaths (Liu et al., 2019; Poorolajal et al., 2017). Interpersonal problems experienced during adolescence have been consistently noted in the literature as risk factors for suicide ideation in young adulthood (King & Merchant, 2008). Peer victimization (PV), wherein children and adolescents are targets of repeated expressions of aggression by same-aged peers (Olweus, 1993), has become a rapidly recognized interpersonal problem that has been linked to negative outcomes (e.g., depression, anxiety, negative self-worth), including suicide risk (e.g., Van Geel et al., 2014). Given meta-analytic research indicates the prevalence of non-cyber PV is as high as 36% among adolescents (Modecki et al., 2014), more research is needed to clarify the association between PV and suicide ideation among college students during this high-risk developmental period.

Experiencing PV during childhood and adolescence has been established as an interpersonal risk factor for suicide ideation during adolescence (Geoffroy et al., 2016; Klomek et al., 2010; Russell & Joyner, 2001), as well as for suicide ideation and depression in young adulthood (Schneider et al., 2012). PV has traditionally been divided into four subtypes: physical (e.g., pushing, hitting), verbal (e.g., insulting, teasing, threats), indirect/relational (e.g., spreading rumors, social exclusion), and cyberbullying (i.e., hostile or aggressive communication via electronic or digital media; Shäfer et al., 2004; Tokunaga, 2010; Wang et al., 2009). Verbal and indirect PV are highly correlated (r = .83, p < .001; e.g., Varjas et al., 2009) and have been significantly associated with similar negative outcomes (e.g., hopelessness, depression, emotional distress, loneliness; Crick & Bigbee, 1998; Gibb et al., 2004). Additionally, verbal and indirect PV are theoretically related, given they involve establishing and upholding boundaries and status within social groups, where victims are frequently excluded from cliques in manipulative power moves (Rodkin & Hodges, 2003; Rudolph et al., 2014). Given the interpersonal nature of indirect and verbal PV, these forms of PV reflect relational PV more broadly and appear particularly pertinent to understanding suicide risk. Theories of suicidal behavior may provide a useful framework to better understand how negative social experiences, such as relational PV, may be associated with later risk for suicide ideation.

Based on the interpersonal theory of suicide (ITS; Joiner, 2005; Van Orden et al., 2010), interpersonal needs may mediate or explain the association between frequency of relational PV and suicide ideation. The ITS states an individual will develop suicide ideation when experiencing a combination of proximal, interpersonal risk factors, which include perceived burdensomeness (PB; self-hatred and perceiving the self to be a burden or strain on others) and thwarted belongingness (TB; perceiving the self to be alienated from others; Van Orden et al., 2010). Through the lens of the ITS, a bully engaging in relational PV may repeatedly tease, taunt, and exclude a child from their social group. In turn, the victimized child may internalize these interactions and feel as if they do not belong in any social group at school (increase in TB) and perceive themselves as a burden on their peers (increase in PB), thus increasing their risk for suicide ideation. This postulation is consistent with research indicating that childhood peer victimization is linked to many negative social outcomes (e.g., loneliness, low social support; Day et al., 2017) and suicide ideation during adulthood (Schneider et al., 2012).

Previous research supports the association between PV, TB, PB, and suicidal thoughts and behaviors. In particular, the indirect effects of TB and PB significantly mediated the association between lifetime bullying experiences and current suicide ideation in an outpatient sample (Brailovskaia et al., 2019). Another study indicated that the indirect effects of depressive symptoms and PB significantly mediated the association between the intensity of experiencing cyberbullying in primary and secondary school and current suicide ideation (Mitchell et al., 2018). These findings support the utility of the ITS framework and provide support for the salience of TB and PB as theoretical proximal intervening risk factors in the association between PV and suicide ideation. However, research has not focused on retrospective relational (i.e., verbal and indirect) PV, which may be especially important considering their conceptual link to social status and interpersonal relationships, and their association with adolescent and young adult suicide ideation (e.g., Geoffroy et al., 2016; Klomek et al., 2010).

TB and PB may explain how suicide ideation develops as a result of relational PV; however, given that the rate of PV is much higher than the rate of suicide ideation, there may be additional factors that impact the association between retrospective PV, TB and PB, and suicide ideation. These factors may help further clarify which peer victimized individuals may develop suicide ideation when also experiencing TB and PB. Pessimism, or the stable and generalized trait representing the belief that negative events will occur (Scheier & Carver, 1985), has been positively associated with suicide ideation in various populations, including college students (Hirsch et al., 2009), community-based (Chang et al., 2013), and clinical populations (Oquendo et al., 2004). To date, no studies have examined the role of pessimism in the relations between TB and PB, and suicide ideation. It is possible that pessimism may moderate the relations between TB, PB, and suicide ideation, such that the association between TB or PB and suicide ideation may be stronger for those higher in pessimism. Given that individuals who are more pessimistic tend to have more negative and hopeless views of the world and relationships, they may have a similar tendency in regard to TB and PB changing, leading to elevated suicide ideation. This would be consistent with the ITS, such that individuals who are hopeless about TB and PB changing are more likely to develop suicide ideation (Van Orden et al., 2010).

This study aimed to examine the associations between self-reported frequency of retrospective relational PV in primary and secondary school, TB, PB, and current suicide ideation in emerging adults and how these relations vary based on current pessimism. We hypothesized that the frequency of retrospective relational PV would be indirectly associated with current suicide ideation through TB or PB, and that this indirect association would be moderated by pessimism. Specifically, we hypothesized that greater retrospective relational PV would be associated with higher TB or PB, and in turn, higher current suicide ideation. In this model, we predicted that pessimism would moderate the associations between TB or PB and suicide ideation, such that the indirect effects would be significantly stronger when current pessimism is high. We also include supplemental analyses with optimism moderating the indirect effect of retrospective relational PV to current suicide ideation through TB or PB.

Method

Participants

Participants were 330 undergraduate students (Mage = 20.09, SDage = 2.73), recruited from a large university in the Southwestern United States. The sample consisted of more women (n = 189, 57.3%) than men (n = 140, 42.4%), with one participant identifying as transgender (0.3%). The majority of the sample identified as White (n = 212, 64.2%), and the remaining participants identified as Hispanic/Latino (n = 68, 20.6%), African American/Black (n = 24, 7.3%), Asian/Asian American (n = 13, 3.9%), “other” (e.g., biracial; n = 10, 3.0%), or American Indian/Native American (n = 2, 0.6%); one individual (0.3%) did not indicate an ethnicity. In addition, the majority of participants (n = 316, 95.8%) identified as heterosexual. Furthermore, six participants (1.8%) identified as bisexual, four participants (1.2%) identified as gay/lesbian, two participants (0.6%) identified as questioning, and two participants (0.6%) identified as “other.” The majority of the sample indicated no current mental health diagnosis (n = 299, 86.9%), and 45 participants (13.1%) denoted a current diagnosis of a mental health disorder (e.g., depression, anxiety, bipolar).

Measures

Positive and Negative Suicide Ideation Inventory (PANSI)

The PANSI (Osman et al., 1998) is a 14-item self-report assessment of suicide ideation during “the past 2 weeks, including today” rated on a 5-point response scale ranging from 1 = None of the time to 5 = Most of the time. The PANSI is comprised of two subscales: Negative Suicide Ideation which has eight items (PANSI-Negative; e.g., “Thought about killing yourself because you feel like a failure in life?”) and Positive Suicide Ideation which has six items (PANSI-Positive; e.g., “Felt that life was worth living?”). Consistent with other studies (Mitchell et al., 2018; Roush et al., 2017), only the PANSI-Negative Suicide Ideation scale was used in the current study, with higher scores indicating greater current suicide ideation. The average score for the current study (M = 9.22) is consistent with samples of undergraduate students (e.g., M = 10.08 – 10.86; Aloba et al., 2018; Poindexter et al., 2015). The PANSI has demonstrated adequate validity (e.g., Muehlenkamp et al., 2005) and strong reliability among college students (e.g., Mitchell et al., 2018). In the current study, Cronbach’s alpha was .93 for the PANSI-Negative Suicide Ideation scale.

Interpersonal Needs Questionnaire (INQ)

The INQ (Van Orden et al., 2012) is a 15-item self-report assessment of TB and PB rated on a 7-point response scale, ranging from 1 = Not at all true for me to 7 = Very true for me. The INQ is comprised of two subscales independently assessing recent feelings of TB (nine items) and PB (six items), with higher total scores indicating greater TB or PB. The INQ has demonstrated strong validity and internal consistency in previous research (e.g., Van Orden et al., 2012). In the current study, Cronbach’s alphas were .88 for TB and .90 for PB.

Retrospective Bullying Questionnaire-Modified

The Retrospective Bullying Questionnaire Modified (RBQ-M) is a modified 50-item version of the original 46-item measure developed by Shäfer et al. (2004). This self-report assessment is comprised of several sections that assess the frequency, intensity, and coping strategies used in response to types of PV (i.e., direct, indirect, physical, verbal, and cyberbullying) in primary and secondary school and the workplace. Items examining the frequency of retrospective PV were selected for examination in accordance with previous research and the established association between frequency of PV and maladjustment (Graham & Juvonen, 1998; Hong & Espelage, 2012). In the current study, the frequency of retrospective relational PV in primary and secondary school was assessed by combining the two verbal bullying items with the two indirect bullying items, with higher total scores indicating a greater frequency of relational PV. Items were rated on a 5-point response scale ranging from 1 = Never to 5 = Constantly. Cronbach’s alpha was .83 for the frequency of retrospective relational (i.e., verbal and indirect) PV. Additionally, 224 participants (73.9%) reported a history of relational PV during primary and/or secondary school.

Life Orientation Test-Revised

The LOT-R (Scheier et al., 1994) is a 10-item self-report assessment of trait optimism and pessimism on a 5-point response scale ranging from 0 = Strongly disagree to 4 = Strongly agree. The LOT-R is comprised of two subscales: pessimism which has three negatively phrased items (e.g., “If something can go wrong for me, it will”), optimism which has three positively phrased items (e.g., “In uncertain times, I usually expect the best”), and four filler items (i.e., “It’s easy for me to relax”). Optimism is calculated by reverse coding the pessimism items and summing them with the optimism items. The pessimism subscale was used in the primary analyses and optimism was used in the supplemental analyses, with greater total scores indicating greater pessimism and optimism, respectively. The LOT-R has demonstrated strong construct validity (Creed et al., 2002) and adequate reliability in college samples (r = .72; Gustems-Carnicer et al., 2017). In the current study, Cronbach’s alpha was .82 for the pessimism subscale and .82 for optimism.

Depression Anxiety Stress Scales-21

The DASS-21 (Henry & Crawford, 2005) is a 21-item self-report shortened assessment of the original 42-item assessment (Lovibond & Lovibond, 1995) of depression, anxiety, and overall stress severity “over the past week” rated on a 4-point response scale ranging from 0 = Did not apply to me at all to 3 = Applied to me very much, or most of the time. The Depression subscale was used in the current study, with higher scores indicating greater depressive symptom severity. The average score for the current study (M = 2.56) is indicative of low depressive symptoms, which is consistent among samples of college students (M = 3.16; Lew et al., 2019). The DASS-21 has demonstrated strong internal consistency (Osman et al., 2012) and strong reliability (Henry & Crawford, 2005), including among college students (Mitchell et al., 2018). In the current study, Cronbach’s alpha was .83 for the depression subscale.

Procedures

Participants were recruited from undergraduate courses in general psychology. All participants received course credit for participation in the study, and there were no exclusion criteria. After providing consent for study procedures, participants answered all questionnaire items via an online survey program. Demographic questions were presented first, then the subsequent questionnaires followed in a randomized order to control for order effects. Upon completing the study, all participants received a list of local and national mental health/crisis resources. The university institutional review board approved all procedures.

Data Analysis and Data Preparation

Data analyses and preparation were conducted using SPSS-27. Expectation Maximization (EM) was used to impute missing data (Tabachnick & Fidell, 2013), which was appropriate given less than 5% of the data were missing, and Little’s Missing Completely at Random (MCAR) test indicated that the missing data were MCAR, χ2(11,503, N = 344) = 11,667.87, p = .137. Univariate outliers were considered scores greater than ±3.29 standard deviations from the mean for each variable (Tabachnick & Fidell, 2013); no univariate outliers were identified. To check for multivariate outliers, Leverage values, Cook’s distance, and Mahalanobis Distance were examined, which identified 14 cases as multivariate outliers. These 14 cases were removed for data analyses, resulting in a final sample of 330.

A moderated mediation approach (Model 14) was utilized to test the hypotheses (Hayes, 2013). We used 10,000 bootstrap samples to construct bias-corrected 95% confidence intervals with confidence intervals not containing zero indicating statistically significant effects (Hayes, 2013). The frequency of retrospective relational PV was mean-centered and entered as the predictor variable in each analysis, with suicide ideation entered as the criterion variable. TB and PB were mean-centered and entered as separate mediators, in separate analyses. As stated by Hayes (2013), the direct pathway from the predictor variable to the criterion variable does not have to meet significance before observing indirect effects. In each primary analysis, mean-centered pessimism (or optimism in the supplemental analyses) was entered as a moderator of the association between TB or PB (the mediator variables) and suicide ideation (the criterion variable). For moderated mediation, this statistical model requires the indirect effect to be significantly different based on the level of the moderator, which is indicated by a significant Index of Moderated Mediation (Hayes, 2018). Additionally, interactions were reported and simple slopes were calculated for significant interactions to demonstrate the change in the association between TB or PB and suicide ideation at varying levels of pessimism (or optimism in the supplemental analyses; −1 SD, M, and +1 SD).

Results

See Table 1 for bivariate correlations and descriptive statistics. As seen in Figure 1, the hypothesis that the indirect effect of frequency of retrospective relational PV on suicide ideation through PB would be moderated by pessimism was not fully supported, given that significant moderated mediation did not occur (Index of Moderated Mediation = −0.01, 95%, CI = [-0.02, 0.01). However, there was a significant indirect effect of frequency of relational PV on suicide ideation through PB when pessimism was low (-1 SD; indirect effect = 0.18, 95% CI = [0.08, 0.31]), average (indirect effect = 0.15, 95% CI = [0.07, 0.25]), and high (+1 SD; indirect effect = 0.12, 95% CI = [0.05, 0.21]), indicating significant indirect effects through PB across pessimism levels. Notably, as seen in Table 2, there was a significant interaction between PB and pessimism predicting suicide ideation (b = −0.03, 95% CI = [-0.06, −0.01], p = .017), indicating the association between PB and suicide ideation significantly changed based on pessimism, but the change in the PB-suicide ideation association was not large enough to signify moderated mediation. To further probe this significant interaction, simple slope analyses indicated there was a significant positive association between PB and suicide ideation when pessimism was low (-1 SD; b = 0.63, 95% CI = [0.47, 0.79]), average (b = 0.53, 95% CI = [0.43, 0.63]), and high (+1 SD; b = 0.43, 95% CI = [0.34, 0.52]); however, the association between PB and suicide ideation decreased in magnitude as pessimism increased (see Figure 2).

Table 1.

Descriptive Statistics and Bivariate Correlations of Study Variables

Variable 1 2 3 4 5 6 7
1. TB -
2. PB .47** -
3. Depression .41** .38** -
4. Suicide Ideation .35** .53** .39** -
5. Pessimism .34** .31** .41** .20** -
6. Optimism −.41** −.40** −.51** −.27** −.90** -
7. Relational PV .14* .26** .25** .08 .26** −.27** -
M 20.37 7.83 2.56 9.22 5.63 14.30 7.41
SD 10.27 3.73 2.98 3.31 2.93 4.80 3.44
Observed Range 9–50 6–27 0–15 8–26 0–12 1–24 4–19
Possible Range 9–63 6–42 0–21 8–40 0–12 0–24 4–20
Cronbach’s α .88 .90 .83 .93 .82 .82 .83
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Note. TB = Interpersonal Needs Questionnaire, Thwarted Belongingness Score; PB = Interpersonal Needs Questionnaire, Perceived Burdensomeness Score; Depression = Depression Anxiety Stress Scale-21, Depression Score; Suicide Ideation = Positive and Negative Suicide Ideation Inventory, Negative Suicide Ideation Score; Pessimism = Life Orientation Test-Revised, Pessimism Score; Optimism = Life Orientation Test-Revised, Optimism Score; Relational PV = Retrospective Bullying Questionnaire-Modified, Relational Peer Victimization Frequency Score;

*

p < .05.

**

p < .01.

Figure 1. The Moderating Role of Pessimism on the Indirect Association between Frequency of Retrospective Relational Peer Victimization (PV) and Suicide Ideation Through Perceived Burdensomeness (PB).

Figure 1

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Note. Unstandardized path coefficients (b) are reported. Indirect effects of perceived burdensomeness (PB) as a mediator at high pessimism: 95% CI = [0.05, 0.21], average pessimism: 95% CI = [0.07, 0.25], and low pessimism: 95% CI = [0.08, 0.31]. Index of Moderated Mediation: 95% CI = [-0.02, 0.01]. Total model summary: F(1, 325) = 35.63, R2 = .31, p < .001. *p < .05. **p < .01. ***p < .001.

Table 2.

Moderated Mediation Procedure (Process Model 14) Testing the Moderating Role of Pessimism on the Indirect Association between the Frequency of Retrospective Relational Peer Victimization (PV) and Suicide Ideation Through Thwarted Belongingness (TB) or Perceived Burdensomeness (PB)

Predictor Variable b SE t CI [lower, upper limits] p
Criterion Variable: TB (F[1, 328] = 6.28, R2 = .02, p = .013)
 Constant 0.00 0.56 0.00 [−1.10, 1.10] > .999
 Relational PV 0.41 0.16 2.51 [0.09, 0.73] .013
Criterion Variable: Suicide Ideation (F[4, 325] = 12.60, R2 = .13, p < .001)
 Constant 9.12 0.18 50.47 [8.76, 9.47] < .001
 TB 0.10 0.18 5.55 [0.06, 0.13] < .001
 Relational PV 0.01 0.05 0.09 [−0.10, 0.11] .928
 Pessimism 0.10 0.06 1.53 [−0.03, 0.13] .127
 TB X Pessimism 0.01 0.01 1.68 [−0.002, 0.02] .095
Criterion Variable: PB (F[1, 328] = 24.23, R2 = .07, p < .001)
 Constant 0.00 0.20 −0.0001 [−0.40, 0.40] > .999
 Relational PV 0.29 0.06 4.92 [0.17, 0.40] < .001
Criterion Variable: Suicide Ideation (F[4, 325] = 35.63, R2 = .31, p < .001)
 Constant 9.33 0.16 58.20 [9.02, 9.65] < .001
 PB 0.53 0.05 10.61 [0.43, 0.63] < .001
 Relational PV −0.07 0.05 −1.48 [−0.16, 0.02] .139
 Pessimism 0.06 0.06 1.07 [−0.05, 0.17] .286
 PB X Pessimism −0.03 0.01 −2.41 [−0.06, −0.01] .017
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Note. Suicide ideation = Positive and Negative Suicide Ideation Inventory, Negative Suicide Ideation Score. TB = Interpersonal Needs Questionnaire, Thwarted Belongingness Score; PB = Interpersonal Needs Questionnaire, Perceived Burdensomeness Score; Relational PV = Retrospective Bullying Questionnaire-Modified, Relational Peer Victimization Frequency Score. Pessimism = Life Orientation Test-Revised, Pessimism Score; TB X Pessimism = The multiplied effect of TB and Pessimism Scores. PB X Pessimism = The multiplied effect of PB and Pessimism Scores.

Figure 2. Simple Slopes of the Relation Between Perceived Burdensomeness (PB) and Suicide Ideation Across Levels of Pessimism (± 1 SD).

Figure 2

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Note. Individuals who are low in Pessimism have a stronger significant positive relation between Perceived Burdensomeness (PB) and Suicide Ideation (PANSI Negative; b = 0.63, p < .001) than individuals who are high in Pessimism (b = 0.43, p < .001). Low Pess = −1 SD on Pessimism. High Pess = +1 SD on Pessimism. Suicide Ideation = Positive and Negative Suicide Ideation, Negative Suicide Ideation Subscale. The scale of the y-axis is consistent with the observed range of 8–26 for suicide ideation.

As seen in Figure 3, the hypothesis that the indirect effect of frequency of retrospective relational PV on suicide ideation through TB would be moderated by pessimism was not supported given that significant moderated mediation did not occur (Index of Moderated Mediation = 0.004, 95% CI = [-0.002, 0.01]).1 There was a significant indirect effect of frequency of retrospective relational PV on suicide ideation through TB when pessimism was low (-1 SD; indirect effect = 0.03, 95% CI = [0.001, 0.07]), average (indirect effect = 0.04, 95% CI = [0.01, 0.08]), and high (+1 SD; indirect effect = 0.05, 95% CI = [0.01, 0.11]), indicating significant indirect effects through TB across pessimism levels. However, there was not a significant interaction between TB and pessimism predicting suicide ideation (b = 0.01, 95% CI = [-0.002, 0.02], p = .095); therefore, simple slopes were not examined.2

Figure 3. The Moderating Role of Pessimism on the Indirect Association between Frequency of Retrospective Relational Peer Victimization (PV) and Suicide Ideation Through Thwarted Belongingness (TB).

Figure 3

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Note. Unstandardized path coefficients (b) are reported. Indirect effects of thwarted belongingness (TB) as a mediator at high pessimism: 95% CI = [0.01, 0.11], average pessimism: 95% CI = [0.01, 0.08], and low pessimism: 95% CI = [0.001, 0.07]. Index of Moderated Mediation: 95% CI = [-0.002, 0.01]. Total model summary: F(4, 325) = 12.60, R2 = .13, p < .001. *p < .05. **p < .01. ***p < .001.

Supplemental Analyses.

Analyses were also conducted to include the potential moderating role of the full-scale optimism trait, given it is a dimensional trait related to pessimism (see the Supporting Information document, Table S1). Results indicated that the indirect effect of frequency of retrospective relational PV on suicide ideation through PB was not moderated by optimism (Index of Moderated Mediation = 0.003, 95%, CI = [-0.005, 0.01]). However, there was a significant indirect effect of frequency of retrospective relational PV on suicide ideation through PB when optimism was low (-1 SD; indirect effect = 0.13, 95% CI = [0.06, 0.22]), average (indirect effect = 0.15, 95% CI = [0.07, 0.24]), and high (+1 SD; indirect effect = 0.16, 95% CI = [0.06, 0.28]), indicating significant indirect effects through PB across optimism levels. In addition, the interaction between PB and optimism predicting suicide ideation was not significant (b = 0.01, 95% CI = [-0.004, 0.03], p = .151); therefore, simple slopes were not examined.

The indirect effect of frequency of retrospective relational PV on suicide ideation through TB would be moderated by optimism was not fully supported, given that significant moderated mediation did not occur (Index of Moderated Mediation = −0.004, 95%, CI = [-0.01, 0.00). However, there was a significant indirect effect of frequency of relational PV on suicide ideation through TB when optimism was low (-1 SD; indirect effect = 0.05, 95% CI = [0.01, .11]) and average (indirect effect = 0.04, 95% CI = [.01, .07]), but not when optimism was high (+1 SD; indirect effect = 0.02, 95% CI = [-0.01, 0.05]), indicating significant indirect effects through TB across average and low optimism levels. Although moderated mediation was not significant, the association between TB and suicide ideation significantly changed based on optimism as indicated by the significant interaction, but the change in the TB-suicide ideation association was not large enough to signify moderated mediation. To probe the interaction, simple slope analyses indicated there was a significant positive association between TB and suicide ideation when optimism was low (-1 SD; b = 0.13, 95% CI = [0.08, 0.18]) and average (b = 0.09, 95% CI = [0.05, 0.12]), but not when optimism was high (+1 SD; b 0.04, 95% CI = [-0.01, 0.09]); the association between TB and suicide ideation was weakest at high optimism (see the Supporting Information document, Figure S1).

Discussion

This study tested whether self-reported frequency of retrospective relational PV was indirectly related to current suicide ideation through TB or PB and how these indirect associations were moderated by pessimism among emerging adults. Contrary to our hypotheses, there was not significant moderated mediation, such that pessimism (or optimism) did not impact the indirect associations between frequency of retrospective relational PV and current suicide ideation through TB or PB. Instead, our findings suggest that retrospective relational PV negatively impacts perceptions of social relationships through TB or PB, which then, in turn, are associated with suicide ideation, regardless of pessimism (or optimism). These findings support theoretical underpinnings outlined by the ITS (Joiner, 2005; Van Orden et al., 2010), which posits that TB and PB serve as proximal risk factors in the development of suicide ideation (Chu et al., 2017). Additionally, we found that retrospective relational PV was not significantly bivariately or directly associated with suicide ideation, contrary to previous literature suggesting PV is associated with suicide ideation (e.g., Brailovskaia et al., 2019; Nansel et al., 2001).

Although not to the extent of impacting the indirect effects, pessimism interacted with PB, but not with TB, such that the association between PB and suicide ideation increased in magnitude as pessimism decreased. This finding suggests that when a person is less pessimistic, PB may be a better indicator of their current suicide ideation than when a person is more pessimistic. Perhaps feelings of burden are less impactful on suicide ideation when in the presence of more globally perceived negative outcomes. Furthermore, as seen in Figure 2, if individuals are high in PB, their estimated suicide ideation scores are similar, regardless of whether they are low or high in pessimism. When compared to individuals low in both PB and pessimism, individuals who are high in PB, in combination with high pessimism, have the highest estimated suicide ideation. When examining optimism, we found that it impacted the association between TB, but not PB, and suicide ideation; however, not to the extent of impacting the indirect effects. Specifically, the association between TB and suicide ideation was weakest when optimism was high. This suggests optimism may buffer against the negative effects of TB, such that those who have more globally positive expectations about future outcomes are less likely to report elevations in suicide ideation even when experiencing TB.

Although neither pessimism or optimism impacted the indirect association between frequency of retrospective relational PV and current suicide ideation through TB or PB, it is important that future research replicates these findings. It appears that those who have been victimized by their peers tend to experience higher TB and PB, which is related to current suicide ideation regardless of pessimism or optimism. Additionally, pessimism and optimism appear to impact the relation between TB or PB and suicide ideation when adjusting for relational PV. Given our findings focused on relational PV, future research could benefit from comparing different forms of PV in relation to these constructs and suicide ideation. Future research should also consider the role that pessimism and optimism may have on the association between TB or PB and suicide ideation outside of the context of PV. It may also be important to consider how the measurement of pessimism and optimism may influence our understanding of these associations. Previous studies that have examined pessimism and optimism as a single dimensional trait found that more optimism relative to pessimism is a potential protective factor against suicide ideation (e.g., Chang et al., 2013). Our findings suggest considering both optimism and pessimism is important, but findings may vary depending on whether pessimism is measured separately from optimism.

The current findings have relevant implications for suicide risk assessment and treatment. These findings increase the understanding of how relational PV may place youth at higher risk for future suicide ideation, and thus, begin to highlight potential targets for PV prevention and intervention programs. For example, anti-bullying programs implemented in primary and secondary schools to decrease relational PV (Ttofi & Farrington, 2011) may subsequently decrease suicide ideation. To potentially improve the effectiveness of these programs for reducing suicide ideation, they could target feelings of TB and PB directly to decrease suicide ideation. Additionally, student counseling centers treating young adults should consider assessing previous relational PV, as well as feelings of TB and PB, given the current findings suggest these may be indicators of elevated risk for suicide ideation. It should be noted that perceptions of past PV are clinically relevant given the long-term negative effects on mental health outcomes and suicide risk (e.g., Klomek et al., 2010; Schneider et al., 2012). It may also be beneficial to implement cognitive behavioral therapy as a treatment for reducing TB and PB (Joiner et al., 2009) when a history of relational PV is present, given that these interpersonal risk factors significantly cross-sectionally mediated the association between frequency of retrospective relational PV and current suicide ideation. Furthermore, considering whether an individual has more globally negative or positive expectations related to future outcomes (i.e., pessimism and optimism) may inform risk assessment and treatment. For example, for individuals who are more pessimistic, PB may be a weaker indicator of suicide ideation but targeting both PB and pessimism may reduce suicide risk. Whereas, for more optimistic individuals, TB is a weaker predictor of suicide ideation and targeting optimism may buffer against feelings of TB.

Although the current study extends the existing literature, our findings should be viewed in the context of limitations. Due to the cross-sectional design of this study, causality or temporal relationships cannot be determined between variables. Given that the negative effects of PV experienced during childhood and adolescence persist throughout adolescence and young adulthood, future studies should consider the use of longitudinal designs. For example, ecological momentary assessment could more accurately capture PV experiences and the interpersonal responses and risk factors as they occur, and how these factors may be associated with the development of suicide ideation. Furthermore, our findings may not be generalizable to other college-aged samples in other geographic regions. Given the promising results of the current study, future studies should consider replicating our findings utilizing other more clinically severe samples with elevated rates of suicide ideation. Additionally, research should also consider other personality traits or cognitive constructs (e.g., hopelessness, introversion, neuroticism) rather than stable and global characteristics (i.e., pessimism), that may moderate the indirect association between retrospective relational PV and suicide ideation through TB or PB. Moreover, self-report measures were used; in particular, PV was assessed retrospectively, which may introduce reporting bias and recall bias. Future researchers should assess how the frequency of verbal and indirect PV relates to suicide ideation within a more recent context.

Despite these limitations, this study has two major contributions: (1) it improved our understanding of the association between retrospective relational PV and suicide ideation among emerging adults through the lens of the ITS, and (2) it contributed to our understanding of the ITS by examining the role of pessimism and optimism in relation to TB and PB and suicide ideation. Continued work in this area will enhance our understanding of suicide risk and protective factors, including PV, pessimism, and optimism, as well as possible intervention targets.

Supplementary Material

Supporting Information

Acknowledgments

Time for this research was supported, in part, by grants from the National Institute of Mental Health (T32 MH020061; L30 MH120575; R01 MH115922).

Footnotes

We have no known conflict of interest to disclose.

1.

The hypothesized moderated mediation models were also conducted adjusting for depressive symptoms, but this did not change the pattern or statistical significance of the results. Because the statistical significance of results in both models did not change when including depressive symptoms as a covariate, and considering the theoretical and statistical concerns that can arise when including depressive symptoms as a covariate on suicide ideation (see Mitchell et al., 2017; Rogers et al., 2018), we retained our originally hypothesized models.

2.

Limited literature exists that compares different forms of PV; thus, we assessed the other types of frequency of retrospective PV (i.e., physical PV and cyberbullying) on suicide ideation through TB or PB and how pessimism would moderate the relation between TB or PB and suicide ideation. We found consistent results between all forms of PV that are described in the primary analysis.

Data Availability Statement

Data is available upon request. The data is not publicly available. Please contact the corresponding author for more information.

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Supporting Information
NIHMS1750137-supplement-Supporting_Information.docx (23KB, docx)

Data Availability Statement

Data is available upon request. The data is not publicly available. Please contact the corresponding author for more information.

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