Cognitive Trajectories After Surgery, a Clinical, Observational Feasibility Study

Research problem and specific questions: Approximately 2.8 million surgeries are conducted yearly in Sweden and of these almost 50% are persons ≥ 60 years. Postoperative cognitive recovery is a concern for older persons. To date, there is no evidence for treating postoperative neurocognitive decline (POCD) and no assessment of cognitive function is routinely performed. The purpose is to is to test digital monitoring in clinical practice: I) test recruitment process and measure attrition rate; II) estimate the difference in main clinical outcomes (POCD) that will inform sample size calculations for the longitudinal observational mixed methods study, III) determine the usability and feasibility of digital monitoring. Participants: 50 patients ≥60 years undergoing inpatient surgery. Outcomes: depression, frailty, cognitive function, postoperative recovery and functional status .

The aim is to evaluate the digital cognitive monitoring (Mindmore-P) in clinical practice by:

I) Test recruitment process and measure attrition rate. II) To establish whether it is possible to detect early signs of neurocognitive decline, using a digital postoperative cognitive screening tool i.e. Mindmore-P.

III) To investigate if there are any associations between choice of anesthetic drugs, delirium, duration of anesthesia, preoperative frailty, depression symptoms, postoperative delirium, physical function, and early postoperative recovery.

IV) Determine the usability and feasibility of Mindmore-P. V) Determine patients' experiences of early cognitive recovery in relation to signs of cognitive decline or no signs measured bythe four tests included in Mindmore-P

METHODS AND ANALYSIS Study design This is an observational feasibility study.

Participants included will be patients undergoing planned non-cardiac surgery with general anesthesia (n=50) at a hospital in Stockholm, Sweden. The sample size is based on the incidence of early cognitive decline at 1-2 weeks postoperatively of approximately 13-25%.

Inclusion criteria:

1. \>60 years of age undergoing elective non-cardiac surgery with general anesthesia.
2. Duration of surgery \>60 minutes
3. Mini-mental state examination (MMSE) score \>24.

Exclusion criteria:

1. Unable to read and speak Swedish
2. Uncorrected severe visual or auditory disorder, disease of the central nervous system, psychiatric diseases including alcoholism or drug dependence, current motor impairment in dominant hand, or colour-blindness.

Recruitment At the patient's preoperative anaesthesia consultation, a research nurse will provide oral and written information about the study. The details of the study and its potential benefits as well as risks will be explained carefully to the patient. If the patient agrees to participate in the study, they will undergo a MMSE screening to examine if they are eligible for the study.

Outcomes, look below.

Analysis Descriptive statistics of demographic data will be presented with number, percentage, and mean (sd) or min-max, as appropriate. As recommended by Borchers et al review from 2021, mild POCD (1-2 standard deviation \[sd\]) and major POCD (\>2 sd) will be specified for each test result and POCD is present if at least two tests indicates decline.

Usability and attrition rates will be presented with descriptive statistics. Preoperative depression (GDS), frailty (CFS), postoperative recovery (SwQoR), functional status (WHODAS) will be compared between the groups, using Kruskal Wallis ANOVA followed by Mann-Whitney U-test and a Bonferroni correction. To analyse intraindividual differences over time in cognitive performance, the same statistical tests will be used as well as multivariate logistic regression analysis. A p-value of \<0.05 will be statistically significant in all analyses, Qualitative data will be analysed with thematic analysis.

Eligibility Criteria:
Inclusion Criteria:

* \>60 years of age undergoing elective non-cardiac surgery with general anesthesia.
* Duration of surgery \>60 minutes
* Mini-mental state examination score \>24.

Exclusion Criteria:

* Mini-mental state examination, cut-off score of \<23 indicating cognitive impairment
* Unable to read and speak Swedish
* Uncorrected severe visual or auditory disorder,
* Disease of the central nervous system
* Psychiatric diseases
* Alcoholism or drug dependence
* Current motor impairment in dominant hand
* Colour-blindness.