Introduction

Suicidal ideation and non-suicidal self-injury (NSSI) have been persistent issues in society for a considerable length of time and pose significant public health concerns, placing a heavy burden on individuals, families, communities, and counties [1, 2]. Nursing professionals have been shown to have higher rates of suicidal ideation and NSSI. According to the findings of a study conducted by Chen in Taiwan, 18.3% of nurse staff reported experiencing suicidal thoughts within the past week [3]. Additionally, a survey conducted in Hong Kong revealed that 14.9% of participants had considered suicide within the past year, and 9.3% reported engaging in NSSI within the same time frame [4, 5]. Recent studies have revealed that nurses are more prone to experiencing suicidal ideation and NSSI compared to the general population [4, 6]. The significant occupational stresses, such as heavy workloads and widespread job dissatisfaction, can be attributed to this phenomenon [7, 8]. Additionally, the nature of nursing work can further increase the risk of nurses develo** suicidal ideation and NSSI [4, 9]. Understanding the intricate interplay of factors contributing to suicidal ideation and NSSI among nurses is crucial for develo** effective interventions.

Depressive symptoms are the most commonly reported mental health difficulties among nurse staff [29]. In this context, several studies have confirmed the critical role of bullying behavior in predicting non-suicidal self-injury among children and adolescents [30]. Therefore, it is crucial for hospital administrator to implement effective strategies to prevent and address workplace violence to promote the mental health and well-being of nurse staff.

In light of the significant implications of workplace violence, loneliness, and depressive symptoms on nurses’ suicidal ideation/NSSI, the Interpersonal-Psychological Theory of Suicide (IPTS) offers a comprehensive framework for elucidating the underlying mechanisms [31]. According to IPTS, suicidal behavior results from the interplay between the desire to die and the capability for suicide, with workplace violence potentially augmenting both components. Chronic exposure to violence heightens the desire to die by exacerbating feelings of loneliness and depression, while concurrently diminishing self-control mechanisms, thereby enhancing suicide capability. Despite the acknowledged significance of workplace violence, loneliness, depressive symptoms, and their collective impact on nurses’ mental health, significant gaps persist in understanding the underlying mechanisms. Existing research predominantly focuses on specific demographics, such as adolescents, with limited exploration within the nursing population. Addressing these lacunae is paramount, given the profound implications of NSSI and suicidal ideation on nurses’ well-being. Therefore, our research aims to investigate the mechanism by how workplace violence affects suicidal ideation or NSSI in nurse staff and to examine the mediating roles of loneliness and depressive symptoms, guided by the IPTS framework. The theoretical framework is as follows (Fig. 1).

Fig. 1
figure 1

The conceptual model for whole sample, basing on previous study

Full size image

Methods

Participants

This study was a cross-sectional design by convenient sampling methods. Participants were recruited from 18 local governmental hospitals of Dehong districts, Yunnan province, China, in July 2022. Participants can complete our survey by wenjuanxing software, which is biggest online questionnaires platform. Our inclusion criteria are: (1) Works in 18 local governmental hospitals; (2) Were not practice nurse; (3) Volunteered this survey and provided written informed consent. Our trained investigator fully interpreted the aim of this survey for each participants. With the help of nursing department of each hospital (distributing our questionnaire links), a total of 1965 nurse staffs were involved in this survey and 1774 questionnaires were completed, with a response of 90.3%. This study was approved by the Ethics Committee of Dehong people’s hospital (Code: DYLL-KY032).

The methodology employed the cross-sectional survey formula to determine the sample size, defined as follows:

$${\rm{N}} = \frac{{z_{1 - \partial /2}^2 \times pq}}{{{d^2}}}$$

Z1−α/2 represents the critical value for significance testing, with α set at 0.05, corresponding to 1.96. The variable p denotes the prevalence rate of psychological health issues, while q is its complement (q = 1-p). The parameter d signifies the permissible error, where d is set at 0.2p. Previous research indicates a spectrum of prevalence rates for suicidal ideation or NSSI problems among nurses, spanning from 9.1 to 10.8% [4, 32,33,34]. For this investigation, the conservative estimate of 9.1% was adopted for computations, necessitating a minimum sample size of 1267 participants, factoring in a non-response rate of 25%.

Measures

Socio-demographic variables

Basic socio-demographic variables were collected including: age, sex, ethnic, marital status, residence, monthly income, educational level and work experience (years).

Workplace violence

The Chinese version of workplace violence scale (WVS) was used to assess workplace violence in this study [35]. WVS consists of five dimensions (PA: physical assault, EA: emotional abuse, T: threats, VSH: verbal sexual harassment, SA: sexual abuse) and each dimension were evaluated by a self-report item (e.g., EA: Have you encountered the emotional abuse from patients or patients’ relatives in the past years? Including cursing, disrespect, and disparagement words). Each item can been respond to zero times (scored 0), one time (scored 1), two or three times (scored 2), more than three times (scored 3). Higher sum score indicated severe level of workplace violence. This scale have been confirmed good validity and reliability in China [36], with the Cronbach’s α = 0.76 in this study.

Loneliness

Three-item loneliness scale was used to assess loneliness [37]. It is consists of three items (e.g., how often do you feel isolated from others? ), with response of hardly ever (scored 1), some of the time (scored 2), often (scored 3). A total score of this scale ranged from 3 to 9, with higher sum scores indicating severe level of loneliness. This scale have been used in the Chinese nurse population [38, 60]. Our study highlights the need for comprehensive screening and intervention programs in healthcare settings, including those aimed at reducing workplace violence and addressing mental health issues such as loneliness and depressive symptoms. It is recommended that hospitals provide professional psychological consultations and support from administrators and nurse managers to nurses who report experiences of workplace violence.

There are several limitations that need to be considered in this study. Firstly, one of the primary limitations of this study lies in its cross-sectional design, which precludes the establishment of causal relationships between variables. While this study offers valuable insights into the associations among variables, it cannot definitively establish causality. To mitigate this limitation, future longitudinal studies are recommended to explore the temporal sequence of events and changes in variables over time, facilitating a more precise evaluation of causality. Longitudinal studies, by tracking participants over an extended period and gathering data at multiple time points, can furnish stronger evidence for causal inferences and a deeper comprehension of the interplay among the variables under scrutiny. Secondly, participants were recruited through convenience sampling solely from a specific region in China, potentially constraining the generalizability of our findings to a nationally representative sample. In comparison with Wang’s study, notable disparities emerged, particularly concerning sex (χ²/df = 22.119, p < 0.05) and marital status (χ²/df = 70.569, p < 0.05) [61]. Consequently, future research endeavors should consider a more expansive sampling approach to enhance the generalizability and representativeness of our findings. Thirdly, it is noteworthy that our study did not account for the potential influence of confounding variables, such as job stress, social support, or co** strategies, on the relationship between workplace violence and suicidal ideation/NSSI. Future research endeavors should consider incorporating these variables to provide a more comprehensive understanding of the dynamics at play. Finally, potential reporting and recall biases might affect the accuracy of this study’s conclusions. Reporting bias could lead to underestimating suicidal ideation or non-suicidal self-injury among nurses due to reluctance to disclose. Meanwhile, recall bias could influence the reliability of nurses’ recollections of past events. To address these biases, future studies could employ more objective measurement methods, such as validating self-reported information using medical records. Longitudinal studies could also help mitigate recall bias.

Conclusion

The present study has identified loneliness and depressive symptoms as partial mediators in the relationship between workplace violence and suicidal ideation/NSSI among nurses. These findings imply that interventions to prevent NSSI and suicidal ideation should extend beyond direct approaches, addressing workplace stressors and promoting social connectedness to enhance overall mental health and well-being. Building upon our findings, we propose avenues for future research aimed at enhancing nurse well-being and fostering safer work environments. Future endeavors may involve develo** and evaluating targeted programs encompassing stress management techniques, conflict resolution training, and improved reporting mechanisms for workplace violence incidents. By investing in these prevention and intervention strategies, we can work towards reducing workplace violence occurrences and enhancing the mental health of nurses, thereby creating environments conducive to their well-being and professional fulfillment.