Probing the Association between Cognition, Suicidal Behavior and Tryptophan Metabolism in a Sample of Individuals Living with Bipolar Disorder: A Secondary Analysis

• Published in: Brain sciences Vol. 13; no. 4; p. 693
• Main Authors: Paribello, Pasquale, Squassina, Alessio, Pisanu, Claudia, Meloni, Anna, Dall’Acqua, Stefano, Sut, Stefania, Nasini, Sofia, Bertazzo, Antonella, Congiu, Donatella, Garzilli, Mario, Guiso, Beatrice, Suprani, Federico, Pulcinelli, Vittoria, Iaselli, Maria Novella, Pinna, Ilaria, Somaini, Giulia, Arru, Laura, Corrias, Carolina, Pinna, Federica, Carpiniello, Bernardo, Comai, Stefano, Manchia, Mirko
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.04.2023; MDPI
• Subjects: Affective disorders; affective recognition; Analysis; Bipolar disorder; Cognition; Cognition & reasoning; Ethylenediaminetetraacetic acid; hot cognition; Investigations; Kynurenic acid; Metabolites; Mortality; Quinolinic acid; Serotonin; Statistical analysis; Suicidal behavior; Suicide; suicide lifetime attempts; Suicides & suicide attempts; Tryptophan; tryptophan metabolism; affective recognition; hot cognition; suicide lifetime attempts; tryptophan metabolism
• ISSN: 2076-3425; 2076-3425
• DOI: 10.3390/brainsci13040693

Background and Objectives: Alterations in hot cognition and in the tryptophan metabolism through serotonin (5-HT) and kynurenine (KYN) pathways have been associated with an increased risk of suicidal behavior. Here, we aim at probing the association between Stroop test performances and tryptophan pathway components in a sample of individuals with bipolar disorder (BD). Materials and Methods: We explored the association between the Emotion Inhibition Subtask (EIS) performances of the Brief Assessment of Cognition for Affective Disorders (BAC-A) and plasmatic levels of 5-hydroxytriptophan (5-HTP), 5-HT, KYN, 3-hydroxykynurenine (3-HK), quinolinic acid (QA), and kynurenic acid (KYNA) among subjects reporting lifetime suicide ideation (LSI) vs. non-LSI and subjects reporting lifetime suicide attempts (LSA) vs. non-LSA. Results: In a sample of 45 subjects with BD, we found a statistically significant different performance for LSA vs. non-LSA in the color naming (CN) and neutral words (NW) EIS subtasks. There was a significant association between CN performances and plasma 5-HTP levels among LSI and LSA subjects but not among non-LSI or non-LSA. Conclusions: In our sample, patients with LSA and LSI presented lower performances on some EIS subtasks compared to non-LSA and non-LSI. Moreover, we found an inverse correlation between plasma 5-HTP concentration and some EIS performances in LSA and LSI but not among non-LSA or non-LSI. This may represent an interesting avenue for future studies probing this complex association.