ABSTRACT
Background- Female sex is a known risk factor for long-COVID. With the increasing number of COVID-19 cases, the corresponding number of survivors is also expected to rise. To the best of our knowledge, no systematic review has specifically addressed the gender differences in neurological symptoms of long-COVID. Methods: We included studies on female individuals who presented with specific neurological symptoms at least 12 weeks after confirmed COVID-19 diagnosis from PubMed, Central, Scopus, and Web of Science. The search limit was put for after 01/2020 until 15/06/2024. We excluded studies that did not provide sex-specific outcome data, those not in English, case reports, case series, and review articles. Results: A total of 5632 eligible articles were identified. This article provides relevant information from 12 studies involving 6849 patients, of which 3414 were female. The sample size ranged from 70 to 2856, with a maximum follow-up period of 18 months. The earliest publication date was 16/09/2021 while the latest was 11/06/2024. The following neurological symptoms had significant difference in risk ratio (RR) for female gender: fatigue RR 1.40 (95% confidence interval (CI): 1.22 - 1.60, p<0.001), headache RR 1.37 (95% CI: 1.12 - 1.67, p=0.002), brain-fog RR 1.38 (95% CI 1.08-1.76, p=0.011) depression RR 1.49 (95% CI: 1.2 - 1.86, p<0.001), and anosmia RR 1.61 (95% CI: 1.36 - 1.90, p<0.001). high heterogenicity was found for fatigue, brain fog, and anxiety due to the diverse methodologies employed in the studies. Conclusion- Our findings suggest that women are at a higher risk for long-COVID neurological symptoms, including fatigue, headaches, brain fog, depression, and anosmia, compared to men. The prevalence of these symptoms decreases after one year, based on limited data from the small number of studies available beyond this period.
ABSTRACT
Individuals suffering from long-COVID can present with "brain fog", which is characterized by a range of cognitive impairments, such as confusion, short-term memory loss, and difficulty concentrating. To date, several potential interventions for brain fog have been considered. Notably, no systematic review has comprehensively discussed the impact of each intervention type on brain fog symptoms. We included studies on adult (aged > 18 years) individuals with proven long- COVID brain-fog symptoms from PubMed, MEDLINE, Central, Scopus, and Embase. A search limit was set for articles published between 01/2020 and 31/12/2023. We excluded studies lacking an objective assessment of brain fog symptoms and patients with preexisting neurological diseases that affected cognition before COVID-19 infection. This review provided relevant information from 17 studies. The rehabilitation studies utilized diverse approaches, leading to a range of outcomes in terms of the effectiveness of the interventions. Six studies described noninvasive brain stimulation, and all showed improvement in cognitive ability. Three studies described hyperbaric oxygen therapy, all of which showed improvements in cognitive assessment tests and brain perfusion. Two studies showed that the use of Palmitoylethanolamide and Luteolin (PEA-LUT) improved cognitive impairment. Noninvasive brain stimulation and hyperbaric oxygen therapy showed promising results in the treatment of brain fog symptoms caused by long-COVID, with improved perfusion and cortical excitability. Furthermore, both rehabilitation strategies and PEA-LUT administration have been associated with improvements in symptoms of brain fog. Future studies should explore combinations of interventions and include longer follow-up periods to assess the long-term effects of these treatments.