Clinical trial NCT05464355: Biomarkers Associated With Postoperative Cognitive Dysfunction
Official title: Feasibility Study of the Use of Biomarkers to Detect Perioperative Brain Injury: the Association Between Serum Neurofilament Light Chains, Tau Proteins, Continuous Intra-operative Electroencephalography, and the Development of Post Operative Cognitive Dysfunction After Surgery
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Delirium
Postoperative Cognitive Dysfunction
Cognitive Decline
Cognitive Impairment
Keywords: Electroencephalography
Delirium
Neurofilament light chain
Tau protein
Lead sponsor: University of Oxford
Sponsor class: OTHER
Collaborators: name: Oxford University Hospitals NHS Trust
First posted: 2022-07-19
Enrollment: 45
Sex: ALL
Minimum age (years): 65
Standard ages: OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Adults over 65 years of age having major elective surgery under general anaesthesia

Brief summary: Loss of cognitive function after major surgery is a significant risk in older people. It can occur acutely in the days after surgery as delirium or in months to years later as a persistent reduction in brain function termed neurocognitive decline. Together these conditions are called post operative cognitive dysfunction (POCD). They can be acutely distressing for patients and are associated with other problems after surgery.

The causes of post operative cognitive dysfunction are poorly understood. Studies have been limited by a lack of biomarkers to predict which patients are at high risk of developing POCD. Research suggests silent strokes occurring during surgery and different sensitivities to anaesthetic medicines are associated with POCD.

The project consists of a feasibility study to investigate markers that might predict people over 65 years old getting POCD. The first biomarker is a non-invasive monitor of anaesthetics effects on brain function called electroencephalography (EEG): The investigators will identify which EEG patterns predict delirium within five days surgery. The second set of biomarkers are two blood tests of proteins that increase after strokes: these are neurofilament light chains and tau proteins. The investigators will establish if these can be used to predict having POCD up to one year after surgery and long term cognitive impairment up to 5 years after surgery.


Eligibility criteria: Inclusion Criteria:

* Greater than or equal to 65 years of age
* Having elective non-cardiac surgery under general anaesthesia
* Anticipated to have at least 48 hours of inpatient admission
* Able \& willing to give informed consent

Exclusion Criteria:

* Unable to participate in neurocognitive assessments
* Presence of delirium prior to surgery
* Contraindication to use of EEG electrodes (e.g. known allergy to a component of the electrodes)
* Known history of severe traumatic brain injury
* Learning disability specifically with a known structural brain lesion
* Known history of dementia
* Participants undergoing operations on the carotid artery

Primary outcomes:
measure: Feasibility to conduct the study
timeFrame: 1 year after surgery
Secondary outcomes:
measure: Postoperative delirium incidence and severity
timeFrame: Up to 5 days after surgery
measure: Days alive and at home up to 90 days after surgery
timeFrame: 90 days after surgery
measure: Change in neurofilament light chains and tau proteins levels pre- to post operatively
timeFrame: Up to 2 days after surgery
measure: Postoperative neurocognitive dysfunction and severity
timeFrame: Up to 1 year after surgery
measure: Long term cognitive impairment
timeFrame: Up to 5 years after surgery
Other outcomes:
Locations:
city: Reading
country: United Kingdom
facility: Royal Berkshire NHS Foundation Trust
state: Berkshire
Study officials:
affiliation: University of Oxford
name: Martyn Ezra
role: PRINCIPAL_INVESTIGATOR
References: