I would like to add three aspects to the most welcome review on postoperative cognitive dysfunction (POCD) by PD Dr. med. Ingrid Rundshagen (1).
Because of the significant association between increased interleukin-6 and S100β protein levels and the development of POCD (2), these basic pro-inflammatory markers could be used for POCD screening in a clinical setting. Likewise, the pre-operative ratio of the Alzheimer biomarkers beta-amyloid (1–42) and tau protein in the cerebrospinal fluid (CSF) appears to be of relevant predictive value as it is associated with the incidence of POCD (3).
Cortisol levels should be measured pre- and post-operatively to determine the direct pathogenic effect of stress on cognitive performance, as it has been shown that immediately after surgery, patients with POCD have significantly increased cortisol levels compared to patients without post-operative deficits (4). Future research should also explore other factors which may play a role in POCD, such as ubiquitin C-terminal hydrolase L1, body weight or the number of units of blood transfused perioperatively.
Footnotes
Conflict of interest statement
The author declares that no conflict of interest exists.
References
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