Cognitive reserve and the risk of postoperative neurocognitive disorders in older age

Friedrich Borchers; Miriam Rumpel; Jochen Laubrock; Claudia Spies; Petra Kozma; Arjen Slooter; Simone J T van Montfort; Sophie K Piper; Janine Wiebach; Georg Winterer; Tobias Pischon; Insa Feinkohl

doi:10.3389/fnagi.2023.1327388

Cognitive reserve and the risk of postoperative neurocognitive disorders in older age

Front Aging Neurosci. 2024 Feb 5:15:1327388. doi: 10.3389/fnagi.2023.1327388. eCollection 2023.

Authors

Friedrich Borchers¹, Miriam Rumpel², Jochen Laubrock², Claudia Spies¹, Petra Kozma³, Arjen Slooter⁴, Simone J T van Montfort⁴, Sophie K Piper^{5

6}, Janine Wiebach^{5

6}, Georg Winterer^{1

7

8}, Tobias Pischon^{9

10

11

12}, Insa Feinkohl¹³

Affiliations

¹ Department of Anesthesiology and Intensive Care Medicine (CCM, CVK), Humboldt-Universität zu Berlin, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.
² Department of Psychology, University of Potsdam, Potsdam, Germany.
³ 2nd Department of Internal Medicine and Nephrological Center, University of Pécs Medical School, Pécs, Hungary.
⁴ Department of Intensive Care Medicine and Brain Center, University Medical Center Utrecht (UMC), Utrecht University, Utrecht, Netherlands.
⁵ Institute of Medical Informatics, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.
⁶ Institute of Biometry and Clinical Epidemiology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.
⁷ Pharmaimage Biomarker Solutions Inc., Cambridge, MA, United States.
⁸ PI Health Solutions GmbH, Berlin, Germany.
⁹ Molecular Epidemiology Research Group, Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.
¹⁰ Core Facility Biobank, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.
¹¹ Biobank Technology Platform, Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.
¹² Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.
¹³ Medical Biometry and Epidemiology Group, Witten/Herdecke University, Witten, Germany.

Abstract

Background: Postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) are postoperative neurocognitive disorders (PNDs) that frequently occur in the aftermath of a surgical intervention. Cognitive reserve (CR) is a concept posited to explain why cognitive health varies between individuals. On this qualitative understanding of cognitive health, factors like IQ, education level, and occupational complexity can affect the impact of neuropathological processes on cognitive outcomes.

Methods: We investigated the association between CR and POD and CR and POCD on data from 713 patients aged≥65 years with elective surgery. Peak pre-morbid IQ was estimated from vocabulary. Occupational complexity was coded according to the Dictionary of Occupational Titles (DOT). Education level was classed according to the International Standard Classification of Education (ISCED). These three factors were used as proxies of CR. In a series of regression models, age, sex, depression, site of surgery, and several lifestyle and vascular factors were controlled for.

Results: Patients with a higher IQ had lower odds of developing POD. We found no significant association between the other two CR markers with POD. None of the CR markers was associated with POCD.

Conclusion: The significant association of a higher IQ with lower POD risk allows for the stratification of elderly surgical patients by risk. This knowledge can aid the prevention and/or early detection of POD. Further research should attempt to determine the lack of associations of CR markers with POCD in our study.

Keywords: cognitive reserve; elective surgery; geriatric assessment; postoperative cognitive dysfunction; postoperative delirium; postoperative neurocognitive disorders.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was funded by the European Union, Seventh Framework Programme [FP7/2007–2013], under Grant agreement no. HEALTHF2–2014-602461 BioCog [Biomarker Development for Postoperative Cognitive Impairment in the Elderly]: http://www.biocog.eu. The funder had no role in the design of this study, collection of data, data analysis, interpretation of results, or writing of this manuscript. We acknowledge financial support from the Open Access Publication Fund of Charité – Universitätsmedizin Berlin.