The connectome in postoperative delirium
Creators: name: Lammers-Lietz, Florian
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Medical Sciences
subject: Anesthesiology
subject: Neurosciences
subject: FOS: Clinical medicine
subject: Medicine and Health Sciences
subject: Life Sciences
subject: Medical Specialties
subject: Neuroscience and Neurobiology

description: Delirium is a condition of acute brain failure, presenting as a fluctuating states of confusion, inattention and deterioration of consciousness. Experience of postoperative deliriu (POD) has a major impact on patients, their families, medical professionals and healthcare systems, since it is associated with prolonged recovery, increased mortality as well as functional and cognitive impairment and care dependence in the long term. Old patients are at particular risk: 15-25% experience POD after elective surgery (Mattison, Ann Intern Med 2020). Although anesthesia is the major modifiable risk factor for POD, evidence for perioperative pharmacotherapy is low (Liu, Evid Based Complement Alternat Med 2019). In delirium, alterations of the cholinergic, GABAergic, serotonergic and catecholaminergic systems have been observed and understanding the role of these neurotransmitter systems is an indispensable prerequisite to develop effective treatment and prevention measures (Maldonado, Am J Geriatr Psychiatry 2013). Cholinergic functional connectivity has only been adressed in two small functional resting-state studies (Choi, Am J Psy 2012; Oh, Aust NZ Psychiatry 2019). Results diffusion tensor imaging study (SAGES) suggested involvement of the basal forebrain cholinergic system (BFCS) fibre tracts in POD based on brain-wide voxel-wise analysis of fractional anisotropy (Cavallari, Brain 2016). We hypothesize that functional and structural connectivity of the BFCS is associated with the incidence of POD in a patient population &gt;/=65years. We will analyse an existing MRI dataset from BioCog study which has been conducted between 2014 and 2017 in the Departments of Anesthesiology of the Charité-Universitätsmedizin Berlin (Germany) and UMC Utrecht (Netherlands). Measurement: Patients underwent a 1h MRI session at 3T before surgery and follow-up after three months. Population: German participants of the BioCog study (surgical patients ≥65 years and MMSE&gt;23 points at baseline undergoing elective surgery with expected duration of anaesthesia &gt;60min. Outcome: POD was defined by fulfilling DSM-5 criteria for delirium, having a positive bed-side screening for delirium (NuDesc≥2, CAM[-ICU]≥1) or evidence for delirium from chart review during the follow-up period until the seventh postoperative day. See also: clinicaltrials.gov NCT02265263 and Winterer, Eur Psychiatry 2018 Working program: I. Establishment of analysis pipelines for DTI tractography of the BFCS to measure cholinergic fibre tract integrity (quantified as fractional anisotropy [FA], mean diffusivity [MD] and kurtosis) Functional connectivity of the BFCS in resting-state fMRI II. DTI tractography of the BFCS will be used to measure cholinergic fibre tract integrity (quantified as fractional anisotropy [FA], mean diffusivity [MD] and kurtosis) Analyses and steps which have already been performed: Individual segmentation of the BFCS for all BioCog patients (Lammers, Neuropsychologia 2016; Heinrich J Gerontol A Biol Sci Med Sci 2021) Current status of the project: application for funding