Randomized Evaluation to Assess Cognitive Training for the Prevention of Post-operative Cognitive Decline (REACT) - a Pilot Study

The REACT trial has been designed as a feasibility study to investigate the impact of pre-, peri-, and postoperative computerized cognitive trainings on the incidence of postoperative cognitive dysfunction. Two different study groups (training programs) will be compared. Each group consists of two training modules of the validated computer based training program of cognitive functioning called RehaCom®. The experimental group consists of the modules 'Topological Memory (MEMO)' and 'Divided Attention 2 (GEA2)'. The active comparator group consists of the modules 'Topological Memory (MEMO)' and 'Working memory (WOME)'. 48 surgical patients undergoing elective urogynecological or breast cancer surgery will preoperatively be randomly assigned to one of two study groups. Before starting the training, patients will complete a neuropsychological test battery comprising the cognitive tests to measure POCD. The tests will be assessed at preoperative baseline visit and at 3-months follow-up. In order to correct change in cognitive performance for practice effects, a group of 24 female surgical control subjects will also prospectively be tested with the cognitive test battery at baseline and 3-months follow-up. The control subjects will be matched to the 2 study groups regarding health status, surgery and age, but will neither undergo the computerized cognitive training program RehaCom®. Further, 24 female control subjects are included from the POCD-Register (EA1/104/16) and will be matched to the 2 study groups as well.

After baseline assessment, the study group patients will be taught to use the training program RehaCom®, and training should start preoperatively as early as possible. The patients are recommended to perform the training daily during inpatient hospital stay, and at least three times a week for 30 to 60 minutes until month 3.

The neuropsychological assessment will be performed at preoperative baseline and at three-months follow-up. Postoperative cognitive dysfunction (POCD) will be classified using the dichotomous approach established by Rasmussen et al in the International Study on postoperative cognitive deficits (ISPOCD) (Rasmussen et al. The assessment of postoperative cognitive function. Acta Anaesthesiol Scand. 2001 Mar;45(3):275-89.) This calculation method defines POCD as a reliable change in pre- and postoperative cognitive performance (difference scores) of each individual in the surgical patients cohort as compared to the changes in a non-surgical control group (reliable change index in either a composite score including cognitive test parameters from all tests in the cognitive test battery or in at least two of the chosen cognitive test parameters).

Secondary outcome measures of this trial comprise structural and functional MRI measures, Electroencephalogram simultaneous with fMRI, intraoperative cerebral oximetry and neuromonitoring, delirium, pain, sleep quality, postoperative complications, frailty, psychological distress, quality of life, training performance and evaluation of the training.