Neuropsychological profile of post Covid-19 syndrome: chapter one, post-Covid-19 syndrome and goal-directed behaviour - a systematic review of standardized neuropsychological test outcomes; chapter two, exploration of the outcomes and experiences of previously hospitalised patients with post Covid-19 syndrome: a mixed methods approach

Abstract

PURPOSE: Chapter one sought to determine whether there is evidence of impairments across the cognitive domains necessary for goal directed behaviour among individuals with post covid- 19 syndrome (PCS) and the extent to which individual/ clinical variables were associated with such deficits. Impairments in these areas may underlie prevailing economic decline in this population. Chapter two sought to examine patients who were presenting with cognitive complaints to increase understanding of the neuropsychological profile of these individuals through their self-reported experiences, their objective cognitive assessments and the relationship between these two assessment areas.

METHOD: In Chapter one, a systematic search strategy was deployed across the following databases: PubMed/MEDLINE, Embase, AMED, PsychINFO, NeuroBITE, Google Scholar and ProQuest Dissertations & Theses. Methodological quality was assessed using the Newcastle- Ottawa Scale adapted for prospective cohort and cross-sectional studies. Chapter two applied thematic analysis to the subjective experiences of 21 PCS patients experiencing ongoing difficulties, alongside their objective cognitive function. Subjective and objective complaints were subsequently compared via correlational analyses.

RESULTS: Chapter one: Of 5998 articles, 19 studies were included; on average, cross-sectional studies were rated as ‘moderate’ and cohort as ‘high’ quality. Impairments were observed across memory, attention and executive function. Individual and clinical differences impacted cognitive impairment variably; depression, anxiety and fatigue negatively so. Chapter two: Thematic analysis identified four main themes related to the types of difficulties experienced; ‘functional consequences’, ‘cognitive changes’, ‘new-onset mental-health difficulties’ and ‘frequency of impact’. No significant differences were identified between the overall sample mean and the normative mean across cognitive domains assessed. However, a pattern of impaired individual test scores was observed across tests where PCS patients presented with primary attentional impairments with an executive component. Significant relationships were observed between subjective complaints of memory and objective cognitive assessments.

CONCLUSIONS: The findings of both chapters highlight the ongoing neuropsychological impact of PCS on patients’ daily lives, up to two years’ post infection. Further research with larger sample sizes and matched controls would support the identification of the cognitive impacts attributable to disease pathology, psychological, clinical variables and their relative contribution.