Impulsivity mediates the association between narcissism and substance-related problems beyond the degree of substance use: a longitudinal observational study

• Published in: BMC psychiatry 2024-04, Vol.24 (1), p.280-17, Article 280
• Main Authors: Hildebrandt, Malin K, Noack, Josepha, Wuellhorst, Raoul, Endrass, Tanja, Jauk, Emanuel
• Format: Article
• Language: English
• Subjects: Addiction; Alcohol use; Analysis; Care and treatment; Complications and side effects; Delusions; Drug use; Humans; Impulse; Impulsive Behavior; Impulsivity; Laws, regulations and rules; Mediation; Methods; Motivation; Narcissism; Observational studies; Prevention; Risk factors; Substance abuse; Substance use; Substance use disorder; Substance use motives; Substance-Related Disorders - complications
• ISSN: 1471-244X; 1471-244X
• DOI: 10.1186/s12888-024-05718-y

Narcissism has been implied as a putative risk factor for substance use disorders (SUDs). However, previous research did not disentangle the degree of substance use from substance-related problems, the symptoms of SUDs. This preregistered study addressed the open question whether grandiose and vulnerable narcissism and their constituent traits convey specific SUD risk, that is, explain substance-related problems beyond the degree of use. Furthermore, we tested whether impulsivity or substance use motives linked to narcissistic self-regulation mediate this association. Narcissism, impulsivity, substance use motives, past-year substance use, and substance-related problems were assessed in 139 (poly-)substance users, 121 of whom completed a one-year follow-up. For significant longitudinal associations between narcissism factors and substance-related problems controlled for the degree of use, we tested impulsivity and substance use motives as mediators. Grandiose narcissism (r =.24, p =.007) and its constituent factors antagonistic (r =.27, p =.003) and agentic narcissism (r =.18, p =.050), but not vulnerable narcissism, prospectively predicted substance-related problems beyond the degree of substance use. Associations of grandiose narcissism and antagonistic narcissism with substance-related problems were fully mediated by impulsivity, but not substance use motives. Impulsivity explained roughly one third of the association of both grandiose (P̂  = 0.30) and antagonistic narcissism (P̂  = 0.26) with substance-related problems. We demonstrate that grandiose narcissism- particularly antagonistic but also agentic narcissism- is specifically linked to substance-related problems beyond the degree of substance use. The mediating effect of impulsivity but not substance use motives suggests that impulsivity may be a more important mechanism than narcissistic self-regulation in promoting SUD in narcissism. However, future studies may use more targeted measures than substance use motives to further probe the role of self-regulation. Similar result patterns for alcohol compared to all substances together indicate that mechanisms may be alike across substances. In conclusion, narcissistic individuals may not use substances more but have a higher SUD risk, informing prevention and treatment.