A Study on The Psychological Determinants of Substance Use among Indian University Students Diagnosed with Borderline Personality Disorder

Background: Borderline personality disorder (BPD) frequently co-occurs with substance use, yet ‎the psychological mechanisms underlying this relationship remain insufficiently understood. This ‎study examines the association between BPD and substance use, with a focus on impulsivity, ‎emotional dysregulation, anxiety, and depression.‎ Method: A cross-sectional study was conducted between September 2023 and December 2024 ‎among undergraduate students from multiple institutions within a single university in Eastern ‎Odisha. Substance use was assessed using the Alcohol, Smoking, and Substance Involvement ‎Screening Test (ASSIST, Version 3). Psychological constructs were measured using the Difficulties ‎in Emotion Regulation Scale, Barratt Impulsiveness Scale, and Hamilton Depression and Anxiety ‎Rating Scales (HAM-D, HAM-A).‎ Results: Of the total participants, 5.8% (N = 115) met criteria for BPD, and 37.3% (N = 43) of ‎these reported substance use. Cannabis (81.4%) and tobacco (60.5%) were the most commonly used ‎substances among individuals with BPD, whereas alcohol, opioids, sedatives, inhalants, and other ‎drugs showed lower prevalence. Psychological symptoms were highly prevalent in the BPD group, ‎including impulsivity (62.6%), emotional dysregulation (67.9%), anxiety (53.1%), and depression ‎‎(34.8%). Substance use demonstrated strong associations with anxiety (χ² = 20.786, OR = 10.307, p ‎‎< 0.001), emotional dysregulation (χ² = 8.196, OR = 4.296, p = 0.004), and impulsivity (χ² = 12.624, ‎OR = 6.576, p < 0.001). In contrast, depression was not significantly associated with substance use ‎‎(p = 0.409). ‎ Conclusion: Adults with BPD exhibit significantly higher rates of substance use, particularly ‎cannabis and tobacco, compared to their non-BPD counterparts. Psychological factors, especially ‎impulsivity, emotional dysregulation, and anxiety, emerged as strong predictors of substance-use ‎vulnerability, whereas depression did not show a significant association‎.