ABSTRACT
Background: The COVID-19 pandemic caused by SARS-CoV-2 has affected millions of people and can result in both immediate and prolonged neurological effects, including severe complications. While numerous studies have explored the occurrence and consequences of neurological issues in COVID-19, they have often involved limited sample sizes. Purpose: This paper aims to determine the overall occurrence of neurological complications in COVID-19, examine their links with patient demographics, and assess their impact on patient outcomes. Additionally, it seeks to provide an overview of the current understanding of the underlying mechanisms. Methodology: Two systematic reviews were conducted to investigate acute and chronic neurological complications associated with COVID-19. A comprehensive search of medical databases was performed, and relevant studies were evaluated following PRISMA guidelines. Meta-analysis was carried out using the Mantel-Haenszel method, with subgroup analysis and meta-regression used to assess heterogeneity. Results: The analysis of acute complications included 20,011 patients with an average age of 58.1 years and a slight male predominance (55.2%). Common neurological symptoms included loss of taste and smell, headaches, acute encephalopathy, and stroke. For the analysis of long-term complications, 2,094 patients were included. Survivors of COVID-19 experienced ongoing neurological issues ranging from sensory impairments to fatigue, headaches, strokes, and even cognitive and psychiatric problems. Conclusion: By examining various neurological symptoms, this study found a significant association between these manifestations and worse overall outcomes, especially in patients over 60 years old. Identifying high-risk individuals and maintaining a high level of suspicion are crucial for enhancing our understanding of the underlying mechanisms, validating biomarkers, and improving the management of these neurological issues.