Effects of cognitive training and group psychotherapy on cognitive performance of post COVID-19 patients: an exploratory and non-randomized clinical trial.

Cognitive complaints are common signs of the Post COVID-19 (PC) condition, but the extent and type of cognitive impairment may be heterogeneous. Little is known about neuropsychological treatment options. Preliminary evidence suggests cognitive symptoms may improve with cognitive training and naturally over time. In this clinical trial, we examined whether participation in a weekly group consisting of cognitive training and group psychotherapy is feasible and would exert beneficial effects on cognitive performance in PC and whether improvements were associated with intervention group participation or represented a temporal improvement effect during syndrome progression. 15 PC patients underwent an 8-week intervention. Cognitive performance was assessed before and after each intervention group participation. A control group of 15 PC patients with subjective neurocognitive or psychiatric complaints underwent two cognitive assessments with comparable time intervals without group participation. To attribute changes to the intervention group participation, interaction effects of group participation and time were checked for significance. This is an exploratory, non-randomized, non-blinded controlled clinical trial. Within the intervention group, significant improvements were found for most cognitive measures. However, significant time x group interactions were only detected in some dimensions of verbal memory and visuo-spatial construction skills. Significant time effects were observed for attention, concentration, memory, executive functions, and processing speed. The intervention setting was feasible and rated as helpful and relevant by the patients. Our results suggest that cognitive symptoms of PC patients may improve over time. Patients affected by both neurocognitive impairments and mental disorders benefit from group psychotherapy and neurocognitive training. The present study provides evidence for a better understanding of the dynamic symptomatology of PC and might help to develop further studies addressing possible therapy designs. The main limitations of this exploratory feasibility trial are the small sample size as well as the non-randomized design due to the clinical setting.