The Effect of Anhedonia on Suicidal Ideation: The Moderated Mediation Effect of Emotional Intelligence Through Loneliness

Seonghee Lee; Sung-Man Bae

doi:10.30773/pi.2024.0388

Psychiatry Investig > Volume 22(5); 2025 > Article

Lee and Bae: The Effect of Anhedonia on Suicidal Ideation: The Moderated Mediation Effect of Emotional Intelligence Through Loneliness

Original Article

Psychiatry Investigation 2025;22(5):591-601.

Published online: May 15, 2025

DOI: https://doi.org/10.30773/pi.2024.0388

The Effect of Anhedonia on Suicidal Ideation: The Moderated Mediation Effect of Emotional Intelligence Through Loneliness

Seonghee Lee¹

, Sung-Man Bae^1,²

¹Department of Psychology, Graduate School, Dankook University, Cheonan, Republic of Korea

²Department of Psychology and Psychotherapy, College of Health Science, Dankook University, Cheonan, Republic of Korea

Correspondence: Sung-Man Bae, PhD Department of Psychology and Psychotherapy, College of Health Science, Dankook University, 119 Dandae-ro, Dongnam-gu, Cheonan 31116, Republic of Korea Tel: +82-41-550-8142, E-mail: spirit73@dankook.ac.kr

Received January 5, 2025 Accepted March 31, 2025

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Objective

This study investigated the mediating effect of loneliness on the relationship between anhedonia and suicidal ideation, and the moderated mediating effect of emotional intelligence on the relationship between loneliness and suicidal ideation.

Methods

Participants (390 adults; males=194, females=196) aged between 19-59 years completed self-report questionnaires. Frequency and descriptive statistics, correlation analysis, mediating effect analysis, moderating effect analysis, and moderated mediating effect analysis were conducted using SPSS Statistics version 23.0 and the PROCESS Macro for SPSS version 4.2.

Results

Loneliness partially mediated the relationship between anhedonia and suicidal ideation. Additionally, emotional intelligence and its four subfactors moderated the relationship between loneliness and suicidal ideation. Finally, emotional intelligence and its subfactors (self-emotional appraisal, others’ emotional appraisal, emotion utilization) moderated the mediating effect of anhedonia on suicidal ideation through loneliness, verifying the moderated mediating effect.

Conclusion

It clarified the path that anhedonia has on suicidal ideation and confirmed the role of emotional intelligence.

Keywords: Anhedonia, Suicidal ideation, Loneliness, Emotional intelligence, Moderated mediation effect

INTRODUCTION

The WHO’s 2021 report on National Suicide Prevention Strategies states that around 700,000 individuals die by suicide each year [1]. Additionally, one in 10 adults considers suicide at least once in their lifetime [2]. Although suicidal ideation does not necessarily lead to suicide attempts or behaviors, it can be a significant factor in predicting and preventing suicide, considering that it is an early stage on the continuum of suicidal behavior [3].

Major risk factors for suicidal ideation include depression, other mental disorders, family history, and substance abuse [4], with depression being a well-known risk factor for suicidal ideation. Recently, in the diagnosis of depressive disorders, low positive affect, characterized by the loss of interest and pleasure, in addition to depressed mood, has been increasingly highlighted. Anhedonia, which is closely related to low positive affect, is a core symptom in approximately 70% of all patients with depressive disorders [5]. Numerous studies have confirmed that anhedonia is strongly associated with suicidal behavior, even after controlling for the severity of depressive symptoms [6,7]. It suggests that anhedonia, independent of depression, can be a risk factor for suicidal ideation [8].

Numerous studies involving students, the public, and individuals with mental disorders have identified anhedonia as a risk factor for suicidal ideation [9,10]. Anhedonia is “a diminished emotional response or interest in stimuli that previously elicited reward or pleasure [11].” Recent meta-analyses have shown that anhedonia is a significant risk factor for suicide in both clinical and control groups [12], with a moderate effect size difference in anhedonia scores between individuals reporting suicidal ideation and those who do not [13].

Individuals reporting anhedonia lack motivation to seek positive emotions, which increases their likelihood of experiencing negative emotions [14]. Additionally, social anhedonia exhibits reduced interest in or desire for social interactions, which may lead to avoidance or withdrawal from social situations [15]. Consequently, individuals experiencing anhedonia may struggle to form meaningful interpersonal relationships and frequently experience negative emotions, such as loneliness [16,17]. A network structure analysis found a strong correlation between anhedonia and loneliness [18]. Other studies have reported that individuals experiencing social anhedonia have poor social networks and high levels of loneliness [15,16].

Loneliness is an unpleasant and distressing emotion that is subjectively experienced when the need for interpersonal relationships is frustrated or deficient [19]. According to the Ministry of Health and Welfare’s Suicide Survey (2018), 48.1% of respondents stated that “loneliness could be a reason for suicide.” Furthermore, 2019 White Paper on Suicide Prevention identified loneliness as one of the major factors prompting the consideration of suicide [20]. It indicates that loneliness is a risk factor for self-harm and suicide attempts. Systematic literature reviews have also revealed that loneliness significantly predicts suicidal ideation and behavior [21,22]. Anhedonia and loneliness are closely associated with suicidal ideation. Previous research17 found that loneliness fully mediated the relationship between social anhedonia and overall social functioning, even after controlling for negative emotions. Another study [18] revealed that individuals who experience anhedonia are more likely to experience loneliness than those who do not.

A prior study23 found that individuals reporting suicidal ideation struggled to understand, regulate, and express their emotions. Many researchers have emphasized the importance of enhancing emotional intelligence in preventing suicidal ideation [24,25]. Emotional intelligence is the ability to evaluate and express emotions of oneself and others, effectively regulate emotions, and utilize emotions. Individuals with high emotional intelligence experience less emotional distress in stressful situations, helping maintain self-esteem and self-efficacy, which mitigates the impact of adverse events [26].

Previous studies have indicated that emotional intelligence is significantly negatively related to suicidal ideation [27,28]. According to a study [29], emotional intelligence therapy for adolescents significantly improved the level of suicidal ideation. A prior study [30] found that, after controlling for gender and age, emotional intelligence weakens the influence of loneliness on suicidal ideation among adolescents experiencing cyberbullying. It suggests that emotional intelligence can interact with loneliness to influence suicidal ideation.

Individuals with high emotional intelligence tend to focus more on positive emotions by considering successful situations compared to those with low emotional intelligence [31]. They also frequently use adaptive coping strategies such as accepting others [32]. Self and other’ emotion appraisal refer to the ability to identify, evaluate, and effectively convey one’s or others’ emotions, respectively. Individuals with high emotional appraisal can detect and implement appropriate regulatory strategies for negative emotional states, such as depression and anxiety, early, and recover quickly from negative emotional experiences [33]. Some studies have shown that individuals with high emotional recognition clarity tend to have lower levels of suicidal ideation [34,35]. Recognizing one’s emotions plays a central role in mindfulness and acceptance-based psychotherapy, which helps reduce suicidal behaviors [36].

Emotion utilization refers to the capacity to comprehend and effectively apply emotional information. Previous studies indicated that emotion utilization ability is negatively correlated with suicidal ideation [27,37]. Individuals with high emotion utilization pay more attention to positive emotions by thinking of successful situations in comparison to those with low emotion utilization [31], and frequently use adaptive coping strategies, such as accepting others [32]. In a study [38], individuals with high emotion utilization were more likely to seek social support from family or friends in sad or adverse situations. Social support is known to be a protective factor against suicidal ideation [4].

Emotion regulation refers to the recognition, understanding, and control of emotions. It is a significant factor influencing suicidal ideation, and lower emotion regulation abilities are associated with increased suicidal behavior [39]. The study [40] found that emotion regulation alleviates the relationship between mental distress (a combination of psychological injury, shame, humiliation, despair, loneliness, fear, and distress) and suicidal ideation among soldiers. Individuals struggling with emotion regulation tend to experience more negative emotions because they do not use effective strategies to regulate emotions [41], which can lead to suicidal ideation.

Previous studies have confirmed the relationship between demographic variables such as gender, age, economic status, and suicidal ideation. Several studies have shown that the frequency of suicidal ideation is higher in women than in men [42,43]. It has also been found that suicidal ideation increases with age2 and that lower income levels are associated with higher suicidal ideation [44]. In particular, it has been reported that individuals with lower income levels have higher suicidal ideation regardless of gender or age group [45].

In summary, this study aimed to examine the relationship between anhedonia and suicidal ideation mediated by loneliness, controlling for gender, age, and economic status, and to investigate the specific roles of emotional intelligence and its subfactors (self-emotion appraisal, others’ emotion appraisal, emotion utilization, and emotion regulation) through a moderated mediation analysis.

METHODS

Participants

This study conducted an online survey using Google Forms with 400 adults aged 19-59 years. In this study, the minimum required sample size was calculated using the G-Power program (3.1.9.6; Kiel University), which indicated that at least 170 participants were needed. The participants were required to read an information sheet and agree to participate before administering the questionnaire. They were informed that they could withdraw from the questionnaire at any time. All items in the survey were self-reported questions, and the participants received a coffee gift card as a reward. After reviewing the surveys, data from ten participants who provided insincere responses were excluded, resulting in a final dataset of 390 participants. Among them, 194 were men (49.7%) and 196 were women (50.3%), with an average age of 38.54 years (SD=10.38). All procedures, including data collection, were approved by the Institutional Review Board of Dankook University (approval no. 2023-10-040). Informed consent was obtained from all individual participants included in the study. All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000 (5).

Measurement tools

Korean Version of the Dimensional Anhedonia Rating Scale

This study used the Korean version of the Dimensional Anhedonia Rating Scale [46]. The scale consists of 26 items divided into four categories: hobbies (nine items), food/drink (six items), social activities (six items), and sensory experiences (five items). Each item is reverse scored on a scale from 0 (strongly agree) to 4 (strongly disagree), with higher scores indicating greater anhedonia. The Cronbach’s α for the entire scale was 0.95, with 0.90 for hobbies, 0.83 for food/drink, 0.87 for social activities, and 0.84 for sensory experiences.

Korean Version of the Beck Scale for Suicide Ideation

This study utilized the Korean adaptation of the Beck Scale for Suicide Ideation [47]. The scale contains 19 items scored from 0 to 2, with higher scores indicating greater suicidal ideation. Cronbach’s α for this scale was 0.93.

Korean-UCLA Loneliness Scale Version 3

This study employed the Korean-UCLA Loneliness Scale Version [48]. This scale measures chronic and state loneliness with 20 items divided equally into positive and negative items. The scores range from 0 (not at all) to 3 (always), with higher scores indicating greater loneliness. Cronbach’s α for this scale was 0.92.

Wong and Law Emotional Intelligence Scale

This study used the Wong and Law Emotional Intelligence Scale [49]. The scale consists of 26 items divided into four subscales: self-emotion appraisal (four items), others’ emotion appraisal (four items), emotion utilization (four items), and emotion regulation (four items). Scores range from 1 (not at all) to 5 (very much), with higher scores indicating higher emotional intelligence. The Cronbach’s α for the entire scale was 0.92, with 0.80 for self-emotion appraisal, 0.76 for others’ emotion appraisal, 0.80 for emotion utilization, and 0.82 for emotion regulation.

Analysis

First, frequency analysis was performed using SPSS 23.0 (IBM Corp.), to determine the demographic characteristics of the participants, and Cronbach’s α was calculated to assess the reliability of each measurement tool. Second, descriptive statistics, including mean, standard deviation, skewness, and kurtosis, were computed, and a Pearson correlation analysis was conducted. Third, the direct effects of the independent variables on the dependent variables and the indirect effects mediated by the mediator variables were tested. PROCESS Macro Model 4 was used to analyze the mediation effects, with bootstrapping employed to test the significance of the indirect effects. Bootstrapping is advantageous over traditional multiple regression because it does not assume normality of the sampling distribution and thus provides greater statistical power [50]. Fourth, the moderating effects of the moderator variables and their sub-factors were tested. For this purpose, PROCESS Macro Model 1 was used to analyze the interaction effects. Mean centering was applied to minimize multicollinearity issues. Mean centering was applied not only to minimize multicollinearity issues but also to facilitate interpretation of interaction effects at meaningful values of the moderator variable. To thoroughly examine interaction effects, the significance of simple regression lines was tested at various levels of the moderator variable (mean -1SD, mean, +1SD mean) to explore interaction effects in detail [51]. Finally, a moderated mediation analysis was conducted using PROCESS Macro Model 14. This analysis combined mediation and moderation models and was conducted if the simple mediation and moderation effects were significant [52]. The model is as shown in Figure 1.

RESULTS

Correlation analysis of main variables

Descriptive statistics, including means and standard deviations, were calculated for each variable, and skewness and kurtosis were computed to verify normal distribution. A normal distribution is indicated if the absolute value of skewness is less than three and the absolute value of kurtosis is less than eight [52]. Descriptive statistics and correlations among the main variables are presented in Table 1.

Mediation effect of loneliness in the relationship between anhedonia and suicidal ideation

The results are presented in Table 2 and Figure 2. First, the direct effect of anhedonia on suicidal ideation (c) was significant (β=0.631, p<0.001), indicating that higher anhedonia is associated with higher suicidal ideation. Next, the effect of anhedonia on loneliness (a) was significant (β=0.730, p<0.001), showing that anhedonia significantly predicts loneliness. Lastly, after controlling for the effect of anhedonia, loneliness had a significant impact on suicidal ideation (b) (β=0.234, p<0.001). Additionally, the effect of anhedonia on suicidal ideation (c’) remained significant after controlling for loneliness, indicating partial mediation by loneliness (β=0.460, p<0.001). The significance of the mediation effect was further confirmed using bootstrapping with the PROCESS Macro. If the 95% confidence interval for the indirect effect did not include zero, the mediating effect was considered statistically significant [53]. The 95% confidence interval for the indirect effect, ranging from 0.0383 to 0.1082, did not include zero, the mediating effect was statistically significant.

Moderating effect of emotional intelligence on the relationship between loneliness and suicidal ideation

The analysis indicated significant interaction effects of emotional intelligence and its subfactors, suggesting a need to further examine how these interactions manifest. To test the flexibility of the simple regression lines, the values of emotional intelligence and its subfactors were set at three levels: mean -1SD, mean, and +1SD mean. Results are shown in Table 3 and Figures 3-7. In groups with low emotional intelligence or its subfactors, higher loneliness was associated with increased suicidal ideation. However, in groups with high emotional intelligence or its subfactors, the impact of loneliness on suicidal ideation decreased.

Moderated mediation effect of emotional intelligence through loneliness in the relationship between anhedonia and suicidal ideation

Anhedonia had a significant positive effect on loneliness (B=0.511, t=19.999, p<0.001) and a significant direct effect on suicidal ideation (B=0.098, t=3.460, p<0.001). Additionally, emotional intelligence had a significant impact on suicidal ideation (B=-0.234, t=-5.622, p<0.001). Furthermore, the interaction effect between loneliness and emotional intelligence on suicidal ideation was significant (B=-0.004, t=-1.968, p< 0.001), indicating that the impact of loneliness on suicidal ideation (B=0.067, t=1.788, p=0.075) varied depending on emotional intelligence. To examine how the size and direction of the mediation effect changed according to the level of emotional Intelligence, a conditional indirect effect was tested for statistical significance using bootstrapping. When emotional intelligence was low (-1SD), the confidence interval for the indirect effect did not include 0, indicating statistical significance. However, at the mean level or a high level of emotional intelligence (+1SD), the confidence interval for the indirect impact was zero, indicating that the effect was not statistically significant.

Moderated mediation effect of self-emotion appraisal through loneliness in the relationship between anhedonia and suicidal ideation

Anhedonia had a significant positive effect on loneliness (B=0.511, t=19.999, p<0.001) and a significant direct effect on suicidal ideation (B=0.117, t=3.904, p<0.001). Additionally, self-emotion appraisal had a significant impact on suicidal ideation (B=-0.456, t=-3.191, p<0.01). Furthermore, the interaction effect between loneliness and self-emotion appraisal on suicidal ideation was significant (B=-0.017, t=-2.296, p< 0.01), indicating that the impact of loneliness on suicidal ideation (B=0.139, t=3.873, p<0.001) varied depending on selfemotion appraisal. To examine how the size and direction of the mediation effect changed according to the level of selfemotion appraisal, a conditional indirect effect was tested for statistical significance using bootstrapping. In all levels of selfemotion appraisal, the confidence interval for the indirect effect did not include 0, indicating statistical significance.

Moderated mediation effect of others’ emotion appraisal through loneliness in the relationship between anhedonia and suicidal ideation

Anhedonia had a significant positive effect on loneliness (B=0.511, t=19.999, p<0.001) and a significant direct effect on suicidal ideation (B=0.138, t=5.029, p<0.001). Additionally, others’ emotion appraisal had a significant impact on suicidal ideation (B=-0.424, t=-3.359, p<0.001). Furthermore, the interaction effect between loneliness and others’ emotion appraisal on suicidal ideation was significant (B=-0.017, t=-2.311, p<0.05), indicating that the impact of loneliness on suicidal ideation (B=0.126, t=3.488, p<0.001) varied depending on others’ emotional appraisal. To examine how the size and direction of the mediation effect changed according to the level of others’ emotion appraisal, a conditional indirect effect was tested for statistical significance using bootstrapping. When others’ emotion appraisal was low (-1SD) or at the mean level, the confidence interval for the indirect effect did not include 0, indicating statistical significance. However, at a high level of others’ emotion appraisal (+1SD), the confidence interval for the indirect impact was zero, indicating that the effect was not statistically significant.

Moderated mediation effect of emotion utilization through loneliness in the relationship between anhedonia and suicidal ideation

Anhedonia had a significant positive effect on loneliness (B=0.511, t=19.999, p<0.001) and a significant direct effect on suicidal ideation (B=0.149, t=5.635, p<0.001). Additionally, emotion utilization had a significant impact on suicidal ideation (B=-0.473, t=-4.084, p<0.001). Furthermore, the interaction effect between loneliness and on suicidal ideation was significant (B=-0.015, t=-2.098, p<0.05), indicating that the impact of loneliness on suicidal ideation (B=0.096, t=2.589, p<0.05) varied depending on emotion utilization. To examine how the size and direction of the mediation effect changed according to the level of emotion utilization, a conditional indirect effect was tested for statistical significance using bootstrapping. When emotional utilization was low (-1SD) or at the mean level, the confidence interval for the indirect effect did not include 0, indicating statistical significance. However, at a high level of emotional utilization (+1SD), the confidence interval for the indirect impact was zero, indicating that the ef-fect was not statistically significant.

Moderated mediation effect of emotion regulation through loneliness in the relationship between anhedonia and suicidal ideation

Anhedonia had a significant positive effect on loneliness (B=0.511, t=19.999, p<0.001) and a significant direct effect on suicidal ideation (B=0.157, t=6.054, p<0.001). Additionally, emotion regulation had a significant impact on suicidal ideation (B=-0.516, t=-4.671, p<0.001). However, the interaction effect between loneliness and the moderating variable of emotion regulation was not significant (B=-0.009, t=-1.224, p=0.222). All results are shown in Table 4.

DISCUSSION

This study examined the mediating effect of loneliness on the relationship between anhedonia and suicidal ideation, and how loneliness impacted suicidal ideation based on emotional intelligence levels. A comprehensive discussion of the results is presented below.

First, the study found that individuals with anhedonia experienced an increase in suicidal ideation. It supports previous studies showing an increase in suicidal ideation with increasing anhedonia [12,13]. A prior study [54] proposed that anhedonia is a psychological state that drives individuals to engage in suicidal behaviors to escape current stressors. From a psychosocial standpoint, suicidal ideation is a strategy for avoiding unpleasant emotions [55]. Individuals with high levels of anhedonia may be less motivated to experience pleasure and may use suicidal ideation as an experiential avoidance strategy to escape psychological pain [56].

Second, loneliness partially mediated the relationship between anhedonia and suicidal ideation. It is consistent with previous research indicating that social anhedonia affects loneliness [15,57] and that loneliness predicts suicidal ideation [22]. Individuals experiencing anhedonia show reduced interest in or need for social interactions, leading to withdrawal or isolation from the social environment. This lack of social support makes them more vulnerable to negative emotions such as loneliness. The study [17] found that loneliness mediates the relationship between social anhedonia and social functioning. Lone-liness arises from frustration with relational needs, and several studies have shown that thwarted relational needs significantly predict suicidal behavior [53,58].

Third, emotional intelligence had a significant moderating effect on the relationship between loneliness and suicidal ideation. Specifically, individuals with high emotional intelligence experienced fewer suicidal ideation than those with low emotional intelligence, even when experiencing loneliness. It supports previous research that identified emotional intelligence as a protective factor against suicidal ideation [24,25]. Emotional intelligence acts as a crucial resource for coping with stress. Individuals with high emotional intelligence are better at recognizing various emotions and minimizing the impact of negative emotions, allowing for quicker recovery and employing appropriate coping strategies, thus experiencing less psychological difficulty [59].

Emotional intelligence and its four subfactors showed significant moderating effects on the relationship between loneliness and suicidal ideation. The ability to recognize emotions helps individuals perceive whether their needs are being met and influences their choice of appropriate subsequent actions, which enhances their psychological well-being [60] Individuals with high emotional appraisal tend to attempt more problemsolving actions [61]. Emotional appraisal acts as a buffer against stress, helping maintain psychological well-being and reducing maladaptive emotion regulation styles, such as rumination, thereby increasing life satisfaction [62].

Individuals with high emotion utilization can intentionally and effectively transform negative emotions into constructive thoughts and behaviors and adapt appropriately to situations [62]. However, another study [63] found that individuals experiencing loneliness tend to struggle with emotional transformation, leading to increased anxiety, rumination, and suicidal ideation [64]. It supports the idea that individuals experiencing loneliness may remain in negative emotions longer, potentially leading to suicidal ideation.

Individuals with high emotion regulation abilities can accept and adjust to their negative emotions appropriately [31,65]. According to a previous study [66], individuals with high emotion regulation are better at managing negative emotions such as anger or anxiety. Moreover, they tend to express their feelings appropriately through interactions with others and view stressful situations positively [67]. Thus, emotion regulation skills can help individuals cope with and mitigate loneliness in interpersonal relationships and act as a protective factor against suicidal ideation.

Finally, the moderated mediation effect of emotional intelligence and its subfactors on the relationships between anhedonia, loneliness, and suicidal ideation was significant. This indicates that the impact of anhedonia on suicidal ideation through loneliness varies depending on an individual’s level of emotional intelligence and its subfactors. According to the previous study [68], emotional intelligence plays a significant role in the formation and maintenance of relationships with parents, friends, and social networks. Basic human needs include belonging to meaningful relationships or groups; when these needs are unmet, it can lead to loneliness and potentially trigger suicidal ideation [69]. High levels of emotional appraisal and utilization enable better understanding and acceptance of oneself and others, positively affecting relationship formation and reducing loneliness, which can ultimately mitigate the impact of suicidal ideation.

The implications are as follows: first, unlike previous studies that focused on negative emotions related to suicide, this study highlights anhedonia, which involves the decrease or absence of positive emotions. It clarified that anhedonia is a significant risk factor of suicidal ideation [12].

Second, although previous research has confirmed that both anhedonia and loneliness affect suicidal ideation, it has not fully explained the specific mechanisms by which anhedonia affects suicidal ideation. This study analyzed the pathways through which anhedonia affects suicidal ideation through loneliness.

Third, by confirming the moderated mediation effect of emotional intelligence and its subfactors on the relationship between anhedonia and suicidal ideation through loneliness, this study demonstrated that emotional intelligence could act as a protective factor. It suggests that emotional intelligence plays a crucial role in the pathway from anhedonia through loneliness to suicidal ideation. It can be used to develop specific suicide prevention and intervention strategies for adults experiencing anhedonia and loneliness. Emotional intelligence is an essential psychological resource that can be developed through training [70] and can serve as a key component in suicide prevention programs. By integrating programs that enhance emotional awareness, emotional expression, interpersonal skills, and stress management into suicide prevention efforts, individuals experiencing anhedonia and loneliness can be supported in gaining a deeper understanding of their emotions, improving their relationships with others, and developing more positive coping strategies.

The limitations were as follows. First, it was based on crosssectional data collected at a single time point. As this study examined the relationships among anhedonia, loneliness, suicidal ideation, and emotional intelligence at one point in time, there were limitations in asserting causal relationships between the variables. While our results suggest that anhedonia influences suicidal ideation through loneliness, alternative explanations exist. These relationships might be influenced by third variables such as depression severity, lack of social support, or interpersonal problems. These possibilities should be examined in future research. Second, this study used self-reported questionnaires to collect data, which may have been influenced by participants’ defensive attitudes or social desirability. Also, the reliance on self-report measures for all variables introduces the possibility of common method variance, which could inflate the observed relationships. Future studies should incorporate multiple assessment methods, including clinician ratings, behavioral observations, and physiological measurements, to mitigate this limitation.

Notes

Availability of Data and Material

The datasets generated or analyzed during the study are available from the corresponding author on reasonable request.

Conflicts of Interest

The authors have no potential conflicts of interest to disclose.

Author Contributions

Conceptualization: Seonghee Lee, Sung-Man Bae. Data curation: Seonghee Lee. Formal analysis: Seonghee Lee. Investigation: Seonghee Lee. Methodology: Seonghee Lee, Sung-Man Bae. Project administration: Sung-Man Bae. Resources: Sung-Man Bae. Software: Seonghee Lee. Supervision: Sung-Man Bae. Validation: Seonghee Lee, Sung-Man Bae. Visualization: Seonghee Lee. Writing—original draft: Seonghee Lee. Writing—review & editing: Sung-Man Bae.

Funding Statement

None

Acknowledgments

This paper has revised and submitted the first author’s master’s thesis from Dankook University 2024.

We would like to thank Editage (www.editage.co.kr) for English language editing.

Figure 1.

The moderated mediation effect of emotional intelligence through loneliness in the relationship between anhedonia and suicidal ideation (Model 14).

Figure 2.

Mediation effect of loneliness in the relationship between anhedonia and suicidal ideation (PROCESS Model 4). a: anhedonia on loneliness, b: loneliness on suicidal ideation, c: anhedonia on suicidal ideation. ***p<0.001.

Figure 3.

Moderation of the effect of loneliness on suicidal ideation at values of the moderator emotional intelligence (PROCESS Model 1).

Figure 4.

Moderation of the effect of loneliness on suicidal ideation at values of the moderator self-emotion appraisal (PROCESS Model 1).

Figure 5.

Moderation of the effect of loneliness on suicidal ideation at values of the moderator others’ emotion appraisal (PROCESS Model 1).

Figure 6.

Moderation of the effect of loneliness on suicidal ideation at values of the moderator emotion utilization (PROCESS Model 1).

Figure 7.

Moderation of the effect of loneliness on suicidal ideation at values of the moderator emotion regulation (PROCESS Model 1).

Table 1.

Correlations, M, and SD among the variables (N=390)

	1	2	3	3-1	3-2	3-3	3-4	4
1. Anhedonia	-
2. Loneliness	0.705^**	-
3. Emotional intelligence	-0.749^**	-0.741^**	-
3-1. Self-emotion appraisal	-0.747^**	-0.637^**	0.876^**	-
3-2. Others’ emotion appraisal	-0.680^**	-0.622^**	0.866^**	0.720^**	-
3-3. Emotion utilization	-0.603^**	-0.663^**	0.876^**	0.674^**	0.687^**	-
3-4. Emotion regulation	-0.580^**	-0.647^**	0.853^**	0.665^**	0.614^**	0.666^**	-
4. Suicidal ideation	0.598^**	0.538^**	-0.629^**	-0.529^**	-0.550^**	-0.527^**	-0.530^**	-
M	51.97	51.66	58.47	15.12	14.77	14.42	14.16	4.96
SD	15.82	11.07	10.88	2.99	3.01	3.27	3.28	6.86
Skewness	0.88	0.15	-0.71	-0.91	-0.68	-0.55	-0.50	1.39
Kurtosis	0.78	-0.73	0.16	0.49	0.11	-0.27	-0.40	0.87

Descriptive statistics and Pearson correlation analysis were conducted. Anhedonia was measured by the Dimensional Anhedonia Rating Scale; loneliness by the UCLA Loneliness Scale Version 3; emotional intelligence and its subfactors by the Wong and Law Emotional Intelligence Scale; and suicidal ideation by the Beck Scale for Suicide Ideation. 1: Anhedonia, 2: Loneliness, 3: Emotional intelligence, 3-1: Self-emotion appraisal, 3-2: Other’s emotion appraisal, 3-3: Emotion utilization, 3-4: Emotion regulation, 4: Suicidal ideation.

^** p<0.01.

M, mean; SD, standard deviation; -, not applicable

Table 2.

The mediating effect of loneliness between anhedonia and suicidal ideation (N=390)

Dependent variable	Suicidal ideation			Loneliness			Suicidal ideation
Dependent variable	B (SE)	β	t	B (SE)	β	t	B (SE)	β	t
Anhedonia	0.273 (0.018)	0.631	15.456^***	0.511 (0.026)	0.730	19.999^***	0.199 (0.025)	0.460	8.059^***
Loneliness							0.145 (0.035)	0.234	4.198^***

Mediation analysis was performed using PROCESS Macro (Model 4) with 5,000 bootstrap samples. Anhedonia was measured by the Dimensional Anhedonia Rating Scale; loneliness by the UCLA Loneliness Scale Version 3; and suicidal ideation by the Beck Scale for Suicide Ideation.

^*** p<0.001.

SE, standard error

Table 3.

Significance of the simple regression lines based on the conditional values of emotional intelligence and its sub-factors (N=390)

Moderator variable	Level	Effect	SE	t	LLCI	ULCI
Emotional intelligence	Mean -1SD	0.178	0.044	4.066^***	0.092	0.264
	Mean	0.115	0.035	3.277^**	0.046	0.184
	Mean +1SD	0.053	0.053	1.368	-0.023	0.128
Self-emotion appraisal	Mean -1SD	0.281	0.0422	6.666^***	0.1984	0.3645
	Mean	0.209	0.318	6.564^***	0.1463	0.2714
	Mean +1SD	0.136	0.0350	3.889^***	0.0674	0.2052
Others’ emotion appraisal	Mean -1SD	0.304	0.041	7.503^**	0.224	0.383
	Mean	0.224	0.031	7.122^***	0.162	0.285
	Mean +1SD	0.143	0.036	3.968^***	0.072	0.215
Emotion utilization	Mean -1SD	0.288	0.041	7.052^***	0.208	0.368
	Mean	0.203	0.033	6.150^***	0.138	0.267
	Mean+1SD	0.117	0.040	2.911^**	0.038	0.196
Emotion regulation	Mean -1SD	0.264	0.039	6.769^***	0.187	0.340
	Mean	0.199	0.032	6.168^***	0.136	0.263
	Mean +1SD	0.135	0.041	3.293^**	0.054	0.215

Moderation analysis was conducted using PROCESS Macro (Model 1) with simple slope analysis at ±1SD. Bootstrap sampling=5,000. Loneliness was measured by the UCLA Loneliness Scale Version 3, suicidal ideation by the Beck Scale for Suicide Ideation, and emotional intelligence and its subfactors by the Wong and Law Emotional Intelligence Scale.

^** p<0.01;

^*** p<0.001.

LLCI, lower limit confidence interval; ULCI, upper limit confidence interval; SD, standard deviation; SE, standard error

Table 4.

Moderated mediation effect of emotional intelligence and its sub-factors (N=390)

	Unstandardized coefficients			LLCI	ULCI
	B	SE	t	LLCI	ULCI
Mediated effect (dependent variable: loneliness)
Constant	-25.221	2.403	-10.494^***	-29.946	-20.495
Anhedonia	0.511	0.026	19.999^***	0.460	0.561
Moderation effect (dependent variable: suicidal ideation)
Constant	-5.413	1.873	-2.890^**	-9.097	-1.730
Anhedonia	0.098	0.028	3.460^***	0.042	0.154
Loneliness	0.067	0.037	1.788	-0.007	0.140
Emotional intelligence	-0.234	0.042	-5.622^***	-0.315	0.152
Loneliness×emotional intelligence	-0.004	0.002	-1.968^*	-0.008	0.000
Constant	-5.936	1.980	-2.998^**	-9.830	-2.043
Anhedonia	0.117	0.030	3.904^***	0.058	0.176
Loneliness	0.139	0.036	3.873^***	0.069	0.210
Self-emotion appraisal	-0.456	0.143	-3.191^**	-0.737	-0.175
Loneliness×self-emotion appraisal	-0.017	0.008	-2.296^*	-0.032	-0.003
Constant	-7.123	1.883	-3.783^***	-10.825	-3.421
Anhedonia	0.138	0.028	5.029^***	0.084	0.192
Loneliness	0.126	0.036	3.488^***	0.055	0.197
Others’ emotion appraisal	-0.424	0.126	-3.359^***	-0.673	-0.176
Loneliness×others’ emotion appraisal	-0.017	0.007	-2.311^*	-0.031	-0.003
Constant	-7.963	1.833	-4.344^***	-11.568	-4.359
Anhedonia	0.149	0.026	5.635^***	0.097	0.201
Loneliness	0.096	0.037	2.589^*	0.097	0.168
Emotion utilization	-0.473	0.116	-4.084^***	-0.700	-0.245
Loneliness×emotion utilization	-0.015	0.007	-2.098^*	-0.029	-0.001
Constant	-7.861	1.837	-4.280^***	-11.473	-4.250
Anhedonia	0.157	0.026	6.054^***	0.106	0.208
Loneliness	0.082	0.036	2.259^*	0.011	0.154
Emotion regulation	-0.516	0.110	-4.671^***	-0.733	-0.299
Loneliness×emotion regulation	-0.009	0.007	-1.224	-0.028	0.005

Moderated mediation analysis was conducted using PROCESS Macro (Model 14) with 5,000 bootstrap samples. Anhedonia was measured by the Dimensional Anhedonia Rating Scale, loneliness by the UCLA Loneliness Scale Version 3, suicidal ideation by the Beck Scale for Suicide Ideation, and emotional intelligence and its subfactors by the Wong and Law Emotional Intelligence Scale.

^* p<0.05;

^** p<0.01;

^*** p<0.001.

LLCI, lower limit confidence interval; ULCI, upper limit confidence interval; SE, standard error

REFERENCES

1. World Health Organization. National suicide prevention strategies. Geneva: World Health Organization; 2021.

2. Ministry of Health and Welfare. [2021 mental health survey report]. Sejong: Ministry of Health and Welfare; 2022. Korean.

3. Ellis A. Rational emotive behavior therapy and the mindfulness based stress reduction training of Jon Kabat-Zinn. J Rat-Emo Cognitive-Behav Ther 2006;24:63-78.

4. Centers for Disease Control and Prevention. Suicide prevention: risk and protective factors for suicide. Atlanta: Centers for Disease Control and Prevention; 2024.

5. Pelizza L, Ferrari A. Anhedonia in schizophrenia and major depression: state or trait? Ann Gen Psychiatry 2009;8:22

6. Ballard ED, Wills K, Lally N, Richards EM, Luckenbaugh DA, Walls T, et al. Anhedonia as a clinical correlate of suicidal thoughts in clinical ketamine trials. J Affect Disord 2017;218:195-200.

7. Spijker J, de Graaf R, Ten Have M, Nolen WA, Speckens A. Predictors of suicidality in depressive spectrum disorders in the general population: results of the Netherlands mental health survey and incidence study. Soc Psychiatry Psychiatr Epidemiol 2010;45:513-521.

8. Whitton AE, Pizzagalli DA. Anhedonia in depression and bipolar disorder. Curr Top Behav Neurosci 2022;58:111-127.

9. Loas G, Lefebvre G, Rotsaert M, Englert Y. Relationships between anhedonia, suicidal ideation and suicide attempts in a large sample of physicians. PLoS One 2018;13:e0193619.

10. Yang X, Liu S, Wang D, Liu G, Harrison P. Differential effects of state and trait social anhedonia on suicidal ideation at 3-months follow up. J Affect Disord 2020;262:23-30.

11. American Psychiatric Association. Diagnostic and statistical manual of mental disorders (5th ed). Arlington: American Psychiatric Association; 2013.

12. Gillissie ES, Le GH, Rhee TG, Cao B, Rosenblat JD, Mansur RB, et al. Evaluating anhedonia as a risk factor in suicidality: a meta-analysis. J Psychiatr Res 2023;158:209-215.

13. Ducasse D, Loas G, Dassa D, Gramaglia C, Zeppegno P, Guillaume S, et al. Anhedonia is associated with suicidal ideation independently of depression: a meta-analysis. Depress Anxiety 2018;35:382-392.

14. Min H, Kwon SM, Lee SA. [Effects of anticipatory and consummatory components of the experience of pleasure on anhedonic depression]. Kor J Clin Psychol 2019;38:1-12. Korean.

15. Barkus E. The effects of anhedonia in social context. Curr Behav Neurosci Rep 2021;8:77-89.

16. Barkus E, Badcock JC. A transdiagnostic perspective on social anhedonia. Front Psychiatry 2019;10:216

17. Tan M, Shallis A, Barkus E. Social anhedonia and social functioning: loneliness as a mediator. Psych J 2020;9:280-289.

18. Yang M, Wei W, Ren L, Pu Z, Zhang Y, Li Y, et al. How loneliness linked to anxiety and depression: a network analysis based on Chinese university students. BMC Public Health 2023;23:2499

19. Seo YS, An SJ, Kim HJ, Ko S. [Review on the conceptual definition and measurement of loneliness experienced among Koreans]. Korean J Psychol Gen 2020;39:205-247. Korean.

20. Ministry of Health and Welfare, Korea Suicide Prevention Center. [2019 white book on suicide prevention]. Seoul: Korea Suicide Prevention Center; 2019. Korean.

21. Calati R, Ferrari C, Brittner M, Oasi O, Olié E, Carvalho AF, et al. Suicidal thoughts and behaviors and social isolation: a narrative review of the literature. J Affect Disord 2019;245:653-667.

22. McClelland H, Evans JJ, Nowland R, Ferguson E, O’Connor RC. Loneliness as a predictor of suicidal ideation and behaviour: a systematic review and meta-analysis of prospective studies. J Affect Disord 2020;274:880-896.

23. Paradiso S, Beadle JN, Raymont V, Grafman J. Suicidal thoughts and emotion competence. J Clin Exp Neuropsychol 2016;38:887-899.

24. Krishnamoorthy P, Kalpana B. Emotional intelligence and suicidal thoughts: how related are they?-Systematic review. Ann Rom Soc Cell Biol 2021;25:9664-9671.

25. Benito OJM, Minaya MB, Zúñiga DNC, Idme KSV. Emotional intelligence as protective factor in adolescents with suicidal ideation. Duazary 2018;15:39-50.

26. Salguero JM, Extremera N, Cabello R, Fernández-Berrocal P. If you have high emotional intelligence (EI), you must trust in your abilities: the interaction effect of ability EI and perceived EI on depression in women. J Psychoeduc Assess 2015;33:46-56.

27. Kwok SY. The moderating role of emotional competence in suicidal ideation among Chinese university students. J Adv Nurs 2014;70:843-854.

28. Mérida-López S, Extremera N, Rey L. Understanding the links between self-report emotional intelligence and suicide risk: does psychological distress mediate this relationship across time and samples? Front Psychiatry 2018;9:184

29. Bonet C, Palma C, Santos GG. Effectiveness of emotional intelligence therapy on suicide risk among adolescents in residential care. Int J Psychol Psychol Ther 2020;20:61-74.

30. Quintana-Orts C, Rey L, Neto F. Are loneliness and emotional intelligence important factors for adolescents? Understanding the influence of bullying and cyberbullying victimisation on suicidal ideation. Psychosoc Interv 2021;30:67-74.

31. Kim BN. [Development of a group counseling program to improve emotional intelligence of university students] [Master’s thesis]. Cheongju: Korea National University of Education; 2016. Korean.

32. Chan DW. Dimensions of emotional intelligence and their relationships with social coping among gifted adolescents in Hong Kong. J Youth Adolesc 2003;32:409-418.

33. Larsen RJ. Toward a science of mood regulation. Psychol Inq 2000;11:129-141.

34. Aradilla-Herrero A, Tomás-Sábado J, Gómez-Benito J. Associations between emotional intelligence, depression and suicide risk in nursing students. Nurse Educ Today 2014;34:520-525.

35. Gómez-Romero MJ, Limonero JT, Trallero JT, Montes-Hidalgo J, Tomás-Sábado J. Relationship between emotional intelligence and negative affect on suicide risk in young university students. Ansiedad Estrés 2018;24:18-23.

36. Linehan MM, Comtois KA, Murray AM, Brown MZ, Gallop RJ, Heard HL, et al. Two-year randomized controlled trial and follow-up of dialectical behavior therapy vs therapy by experts for suicidal behaviors and borderline personality disorder. Arch Gen Psychiatry 2006;63:757-766.

37. Kwok SY, Shek DT. Hopelessness, parent-adolescent communication, and suicidal ideation among Chinese adolescents in Hong Kong. Suicide Life Threat Behav 2010;40:224-233.

38. Izard C, Stark K, Trentacosta C, Schultz D. Beyond emotion regulation: emotion utilization and adaptive functioning. Child Dev Perspect 2008;2:156-163.

39. Colmenero-Navarrete L, García-Sancho E, Salguero JM. Relationship between emotion regulation and suicide ideation and attempt in adults and adolescents: a systematic review. Arch Suicide Res 2022;26:1702-1735.

40. Shelef L, Fruchter E, Hassidim A, Zalsman G. Emotional regulation of mental pain as moderator of suicidal ideation in military settings. Eur Psychiatry 2015;30:765-769.

41. Lee JW, Lee KH. [The relationship between insecure adult attachment and planned happenstance skills in college students: mediating role of emotional regulation difficulty and social anxiety]. Korean J Counsel Psychotherapy 2018;30:1271-1299. Korean.

42. Husky MM, Léon C, du Roscoät E, Vasiliadis HM. Prevalence of suicidal thoughts and behaviors among young adults between 2000 and 2021: results from six national representative surveys in France. Psychiatry Res 2024;333:115763

43. Zhang YY, Lei YT, Song Y, Lu RR, Duan JL, Prochaska JJ. Gender differences in suicidal ideation and health-risk behaviors among high school students in Beijing, China. J Glob Health 2019;9:010604

44. Raschke N, Mohsenpour A, Aschentrup L, Fischer F, Wrona KJ. Socioeconomic factors associated with suicidal behaviors in South Korea: systematic review on the current state of evidence. BMC Public Health 2022;22:129

45. Statistics Korea. Causes of Death Statistics in 2022 [Internet]. Available at: https://kostat.go.kr/board.es?mid=a20108100000&bid=11773&act=view&list_no=427470. Accessed February 24, 2024.

46. Park J, Lee HJ. [Validation of the Korean version of the dimensional anhedonia rating scale (DARS)]. Cogn Behav Ther Korea 2022;22:85-109. Korean.

47. Shin MS, Park KB, Oh KJ, Kim ZS. [A study of suicidal ideation among high school students: the structural relation among depression, hopelessness, and suicidal ideation]. Kor J Clin Psychol 1990;9:1-19. Korean.

48. Jin E, Hwang SH. [The validity of the Korean-UCLA loneliness scale version 3]. Korean J Youth Stud 2019;26:53-80. Korean.

49. Lim J, Chang SS. [A relationship of the emotional intelligence of counselors, counseling relationships, and counseling outcomes]. Korean J Counsel Psychotherapy 2015;27:491-518. Korean.

50. Preacher KJ, Rucker DD, Hayes AF. Addressing moderated mediation hypotheses: theory, methods, and prescriptions. Multivariate Behav Res 2007;42:185-227.

51. Aiken LS, West SG, Reno RR. Multiple regression: testing and interpreting interactions. Thousand Oaks: Sage; 1991.

52. Kline TJB. Psychological testing: a practical approach to design and evaluation. Thousand Oaks: SAGE Publications; 2005.

53. Nock MK, Kazdin AE. Examination of affective, cognitive, and behavioral factors and suicide-related outcomes in children and young adolescents. J Clin Child Adolesc Psychol 2002;31:48-58.

54. Shneidman ES. Suicide as psychache. J Nerv Ment Dis 1993;181:145-147.

55. Xie W, Li H, Luo X, Fu R, Ying X, Wang N, et al. Anhedonia and pain avoidance in the suicidal mind: behavioral evidence for motivational manifestations of suicidal ideation in patients with major depressive disorder. J Clin Psychol 2014;70:681-692.

56. Badcock JC, Shah S, Mackinnon A, Stain HJ, Galletly C, Jablensky A, et al. Loneliness in psychotic disorders and its association with cognitive function and symptom profile. Schizophr Res 2015;169:268-273.

57. Hill RM, Pettit JW. Suicidal ideation and sexual orientation in college students: the roles of perceived burdensomeness, thwarted belongingness, and perceived rejection due to sexual orientation. Suicide Life Threat Behav 2012;42:567-579.

58. Joiner TE, Van Orden KA, Witte TK, Selby EA, Ribeiro JD, Lewis R, et al. Main predictions of the interpersonal-psychological theory of suicidal behavior: empirical tests in two samples of young adults. J Abnorm Psychol 2009;118:634-646.

59. Austin EJ, Saklofske DH, Egan V. Personality, well-being and health correlates of trait emotional intelligence. Pers Individ Differ 2005;38:547-558.

60. Kwak T, Lim J. [The effects of emotional awareness on the psychological well-being of adolescents: cognitive emotion regulation strategies as mediators]. Korean J Child Stud 2019;40:13-24. Korean.

61. Otto JH, Lantermann ED. Individual differences in emotional clarity and complex problem solving. Imagin Cogn Pers 2005;25:3-24.

62. Goleman D. Emotional intelligence: why it can matter more than IQ. Learning 1996;24:49-50.

63. Bangee M, Harris RA, Bridges N, Rotenberg KJ, Qualter P. Loneliness and attention to social threat in young adults: findings from an eye tracker study. Pers Individ Differ 2014;63:16-23.

64. Rogers ML, Joiner TE. Rumination, suicidal ideation, and suicide attempts: a meta-analytic review. Rev Gen Psychol 2017;21:132-142.

65. Kwak YJ. [A study on the development of an education model for emotional intelligence program]. J Korea Open Assoc Early Child Educ 2005;10:333-363. Korean.

66. Kang HW, Kim YH. [Effect of emotional intelligence on the school violence attitude and latent delinquency of adolescents]. Korean Juven Protect Rev 2014;24:31-59. Korean.

67. Lopes PN, Brackett MA, Nezlek JB, Schütz A, Sellin I, Salovey P. Emotional intelligence and social interaction. Pers Soc Psychol Bull 2004;30:1018-1034.

68. Mayer JD, Salovey P. Emotional intelligence and the construction and regulation of feelings. Appl Prev Psychol 1995;4:197-208.

69. Joiner T. Why people die by suicide. Cambridge: Harvard University Press; 2005.

70. Serrat O. Understanding and Developing Emotional Intelligence. In: Serrat O, editor. Knowledge solutions. Singapore: Springer, 2017, p.329-339.