Self-stigma and suicide cognitions in substance use disorder: the mediating role of psychological distress and the moderating role of social support

Individuals with substance use disorders (SUD) experience substantial psychological and social difficulties. A prominent concern is the internalization of stigmatizing societal attitudes, leading to feelings of guilt and worthlessness. This self-stigma has been linked to depression, anxiety, and stress and may contribute to suicide-related cognitions. This study aimed to examine the relationship between self-stigma and suicide cognitions, and to evaluate the potential mediating roles of psychological distress (depression, anxiety, and stress), as well as the moderating role of perceived social support. In this cross-sectional study, 270 adults receiving treatment for SUD at a specialized addiction center were recruited, and analyses were conducted on 265 participants with complete data. Participants completed the Substance Abuse Self-Stigma Scale, Suicide Cognitions Scale-Revised, Depression Anxiety Stress Scale-21, and Multidimensional Scale of Perceived Social Support. Pearson correlations were followed by parallel multiple mediation and moderation analyses using 5000 bootstrap resamples. Self-stigma was positively associated with depression, anxiety, stress, and suicide cognitions, and negatively associated with perceived social support. In the mediation model, only depression significantly mediated the relationship between self-stigma and suicide cognitions, whereas anxiety and stress did not emerge as significant mediators when entered simultaneously. Moderation analyses indicated that perceived support from family, friends, and a significant other each attenuated the association between self-stigma and suicide cognitions, indicating a buffering effect. These findings underscore the clinical importance of routinely assessing self-stigma and depression in SUD populations due to their predisposition to suicidal cognitions. Interventions aimed at reducing self-stigma, enhancing self-worth, and increasing perceived social support should be considered integral components of suicide prevention strategies in this high-risk group.