Neuropsychological deficits in patients with persistent COVID-19 symptoms: a systematic review and meta-analysis

Long-term persistent symptoms of COVID-19 affect 30-80% of patients who have recovered from the disease and may continue for a long time after the disease has been overcome. The duration of these symptoms over time might have consequences that affect different aspects of health, such as cognitive abilities. The main objective of this systematic review and meta-analysis was to objectify the persistent COVID-19 cognitive deficits after acute phase of infection and to summarize the existing evidence. Additionally, we aimed to provide a comprehensive overview to further understand and address the consequences of this disease. Our protocol was registered in PROSPERO (CRD42021260286). Systematic research was conducted in the Web of Science, MEDLINE, PubMed, PsycINFO, Scopus, and Google Scholar databases from January 2020 to September 2021. Twenty-five studies were included, six of which were analyzed for the meta-analysis, and consisted of 175 patients who had recovered from COVID-19 and 275 healthy individuals. Analyses of cognitive performance of post-COVID-19 patients and healthy volunteers were compared using a random-effects model. The results showed an overall medium-high effect size (g= -.68, p=.02) with a 95% CI (-1.05 to -.31), with a significantly moderate level of heterogeneity among studies (Z=3.58, p<.001; I-2=63%). The results showed that individuals who had recovered from COVID-19 showed significant cognitive deficits compared to controls. Future studies should carefully assess the long-term progression of cognitive impairments in patients with persistent COVID-19 symptoms, as well as the effectiveness of rehabilitation interventions. Nevertheless, there is an urgent need to know the profile to speed up development of prevention plans as well as specific interventions. Since more information is being obtained and more studies are being conducted on the subject, the need to examine this symptomatology multidisciplinary to achieve greater scientific evidence of its incidence and prevalence has become increasingly clear.