Network structure of non-suicidal self-injury, alcohol and food addiction, and motivation in bus drivers.

Introduction: Professional bus drivers work in a safety-critical, high-demand context that may increase vulnerability to non-suicidal self-injury (NSSI) and addictive behaviors. However, the symptom-level mechanisms underlying this risk remain poorly understood, limiting the development of targeted, occupation-sensitive prevention and intervention strategies. Methods: Using cluster sampling, 1250 bus drivers were screened in southern Anhui (June 1-July 1, 2023). Participants completed standardized assessments, including a questionnaire based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) proposed criteria for NSSI, the Alcohol Use Disorders Identification Test (AUDIT), the Yale Food Addiction Scale 2.0 (YFAS 2.0), and the Habit, Reward, and Fear Scale (HRFS). We estimated a regularized partial correlation network and constructed Bayesian directed acyclic graphs (DAGs) to examine directional relations. Results: In the regularized partial correlation network, Reward and Fear were the most central nodes, showing the highest levels of strength and expected influence. Alcohol addiction was positively associated with food addiction, NSSI, and motivation. In the DAG, Reward and Fear were positioned as putative upstream nodes while AUDIT as a terminal node. Motivation and food addiction symptoms showed direct edges to alcohol addiction, whereas NSSI showed a putative indirect link to AUDIT via YFAS. Conclusion: These results indicate structured interrelations among NSSI, alcohol addiction, food addiction, and motivation in bus drivers, and nominate Reward- and Fear-related processes as promising intervention targets. These insights offer a new perspective on the psychological network underlying risk behaviors in this occupational group and may inform strategies to improve mental health of transportation workers and public transportation safety.