Research
Perioperative neurocognitive disorders including postoperative delirium (POD) and delayed neurocognitive disorders remain among major neurological complications after surgery. The pathophysiology of these disorders is currently under extensive investigation.
In a prospective clinical research project, our group added new evidence on the link between olfactory function and perioperative cognition. We found that poor preoperative cognitive performance was independently associated with an immediate postoperative decline in olfactory identification function. Additionally, we highlighted the correlation between poor preoperative olfactory function and baseline cognition. Lastly, our work suggested that preoperative olfactory testing would be a way to assess cognitive reserve and, thus, in some cases, to unveil brain frailty in apparently cognitively healthy individuals. Indeed, olfactory dysfunction was an independent predictor of postoperative neurocognitive disorder, primarily through the presence of subjective cognitive concerns.
In another extensive research project, the pathophysiology of POD in cardiac surgery patients has been studied. POD is among the most prevalent complications after cardiac surgery and is associated with increased morbidity and mortality. Although pre-existing cognitive impairment is a major predisposing risk factor, patients’ cognitive status is not systematically assessed during preoperative clinical examination. With the POD-01 study, we aimed to prospectively investigate promising electroencephalographic (intraoperative EEG frontal alpha-band power under general anesthesia), biological (perioperative course of serum neurofilament light, a biomarker of axonal injury) and genetic (apolipoprotein Ee4 carrier status) predictors of POD in order to help identify patients at risk and to potentially provide reasonable alternatives to a comprehensive neuropsychological evaluation.
Team members
- Mona MOMENI, MD, PhD
- Victoria Van REGEMORTER, MD, PhD
- Céline KHALIFA, MD, PhD
Collaborations
- IREC, Brussels, Belgium
Ongoing Projects
We are currently evaluating the utility of specific neurobiomarkers in detection of POD. This ongoing project is in collaboration with the research group of Prof. Bernard Hanseeuw (IoNS).
After having studied the perioperative course of neurofilament light in serum, we intend to pursue our research on the potential correlation between preoperative systemic markers of neurodegeneration, Ab42/40 and tau and the incidence of POD in a population of patients having undergone cardiac surgery. These markers will be correlated with the results of a complete preoperative neurocognitive evaluation.
Otherwise, we will also study the perioperative course of two other biomarkers of neuronal injury, Glial Fibrillary Acidic Protein (GFAP) and Ubiquitin C-terminal Hydrolase (UCHL-1). Indeed, recent studies in cardiac surgery show that the release of these proteins in blood increases postoperatively, supporting the hypothesis of surgery-related brain injury. Surgery-induced neuro-inflammation and subsequent neuronal injury are among the most suspected pathophysiological mechanisms of POD.
We are otherwise elaborating the preoperative EEG data of our study population with the aim to correlate these data with baseline neurocognitive tests.
We are also pursuing our main project of exploring the connection between preoperative olfactory dysfunction and general postoperative outcomes in older surgical patients. More specifically, the aim is to identify the potential underpinning mechanisms, notably by exploring the connection with frailty, cognition, and telomere length. Our major goal is to define the rightful place of olfactory function in the perioperative care algorithm.