Serum levels of olanzapine are associated with acute cognitive effects in bipolar disorder

• Published in: Psychiatry research Vol. 310; p. 114443
• Main Authors: Shoshina, Irina I., Almeida, Natalia L., Oliveira, Milena E.C., Trombetta, Bianca N.T., Silva, Gabriella M., Fars, Julien, Santos, Natanael A., Fernandes, Thiago P.
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01.04.2022
• Subjects: Bayes Theorem; Bipolar disorder; Bipolar Disorder - complications; Bipolar Disorder - drug therapy; Bipolar Disorder - psychology; Cognition; Cognitive tests; Executive Function; Humans; Medication; Neuropsychological Tests; Olanzapine; Olanzapine - therapeutic use; Serum levels; Serum levels; Medication; Bipolar disorder; Cognition; Olanzapine; Cognitive tests
• ISSN: 0165-1781; 1872-7123
• DOI: 10.1016/j.psychres.2022.114443

•Features of cognitive dysfunction in bipolar disorder patients are discussed in the literature, but they are often contradictory.•We found that untreated bipolar disorder patients and patients who were treated with olanzapine performed better in executive function tasks than healthy controls.•We found that bipolar disorder patients who were treated with olanzapine performed better in executive function tasks than unmedicated patients with first-episode bipolar disorder.•The effects of olanzapine on cognitive functions may depend on several aspects. Bipolar (BPD) patients have deficits in cognition, but there are still controversies about the effects of some medications on their cognitive performance. Here, we investigated the relationship between cognition in terms of executive functions, memory, and attention in both first-episode medication-naive BPD patients and BPD patients taking olanzapine. Forty-one healthy controls, 40 unmedicated drug-naive BPD patients, and 34 BPD patients who took only olanzapine were recruited for the study. Cognitive performance was assessed using the Flanker test, Stroop test, and Corsi-block test. Bayesian multivariate regression analysis was run considering maximum robustness to avoid bias and to predict the outcomes. Our results revealed that unmedicated medication-naive BPD patients performed worse than healthy controls and the olanzapine group in some tasks. Additionally, BPD patients who took olanzapine had better cognitive performance than healthy controls and unmedicated BPD patients. The acute cognitive effects were predicted by olanzapine dosage and serum levels (i.e., large effects). The potential pro-cognitive effects of olanzapine in BPD patients should be carefully interpreted by considering various other clinical variables. We expect that our findings will contribute to further research in this area, with the goal of helping other researchers, patients, and the population.