Impact of cognitive reserve on bipolar disorder: a systematic review

Kazuki Matsumoto; Sayo Hamatani

doi:10.3389/fpsyt.2023.1341991

Impact of cognitive reserve on bipolar disorder: a systematic review

Front Psychiatry. 2024 Feb 2:14:1341991. doi: 10.3389/fpsyt.2023.1341991. eCollection 2023.

Authors

Kazuki Matsumoto¹, Sayo Hamatani^{2

3

4}

Affiliations

¹ Division of Clinical Psychology, Kagoshima University Hospital, Research and Education Assembly Medical and Dental Sciences Area, Kagoshima University, Kagoshima, Japan.
² Research Center for Child Mental Development, University of Fukui, Fukui, Japan.
³ Division of Developmental Higher Brain Functions, United Graduate School of Child Development, University of Fukui, Fukui, Japan.
⁴ Department of Child and Adolescent Psychological Medicine, University of Fukui Hospital, Fukui, Japan.

Abstract

Background: Cognitive reserve (CR) is a complex concept that includes premorbid IQ, years of education, and exposure to neuropsychological stimuli through work and leisure. Previous studies have suggested that CR has a positive impact on several aspects of bipolar disorder. Synthesizing the evidence to date is an important work in providing directions for future studies. The objectives of this systematic review to summary impact of CR on onsetting, relapsing bipolar episodes, buffering cognitive dysfunctions, and maintaining quality of life (QOL) in bipolar disorder.

Methods: Two researchers independently reviewed selected paper from three database as PubMed, PsychINFO, and Web of Science. The search keywords were "bipolar disorder" and "cognitive reserve." The selected studies were classified as the levels of evidence according to the criteria of the Oxford Center for Evidence- Based Medicine. The results of the selected studies were summarized according to the objectives.

Results: Thrity six studies were included in this review. People with high CR may have fewer bipolar episodes and alleviate cognitive impairments and dysfunction. CR may keep the functional level in patients with bipolar disorder.

Conclusion: The results of this systematic review suggest that CR may be involved in preventing relapse of bipolar episodes and may alleviate cognitive dysfunction. However, effect on prevention of onset-risk and relapse of bipolar episodes need further investigation in prospective studies.

Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021270293, the protocol was registered with PROSERO (CRD42021270293).

Keywords: bipolar disorder; cognition; cognitive reserve; dysfunction; systematic review.

Publication types

Systematic Review

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This study was supported by Takeda Science Foundation 2020 Medical Research Grant. The facilities that funded the present study were not involved in the design or reporting process of this study. The present paper is the up-date version on 11-Dec-23, the 2023 Kagoshima University Young Researcher Support Grant (Representative: KM) was supported for English proofreading and some manuscript subscriptions.