Neurological Manifestations of Long COVID: A Systematic Review

Background: Severe acute respiratory syndrome coronavirus-2 has been one of the most widespread and devastating global pandemics affecting more than 500 million people worldwide. After the cessation of active infection, the disease continues to have a disabling impact due to the persistence of fatigue, brain fog, anxiety, and depression, among the most common symptoms. This study explores the progression of neurological, neurocognitive, and neuropsychiatric symptoms over a period of 12 months or more following an initial diagnosis of COVID-19. Methods Through an electronic search of eligible studies from PubMed, Cochrane Trial register, and Google Scholar, a total of 10 studies that met the inclusion criteria were used for qualitative analysis. The systematic review highlights the similarities and differences in findings across the included studies. Results Olfactory dysfunction was prevalent in 0.9–51% of individuals, and taste impairment was observed in 1.1–21.3% of individuals. At 12 months, anxiety was more prevalent (3.5–29%) than depression (3.5–26%). Fatigue was the predominant neurocognitive complaint in 56% of individuals with severe COVID-19. Sleep difficulties were reported in 3.8–50% of individuals. Memory impairment followed by headaches and dizziness were also among the neurocognitive symptoms reported at 12 months. Conclusions From our study, we found that there is a significant neurological burden one year following the diagnosis of COVID-19. Further studies exploring the pathological mechanisms of neurological long COVID-19 are necessary to delineate better the mechanisms behind several long-term Neurological manifestations of COVID-19.