Exploring the clinical association between neurological symptoms and COVID-19 pandemic outbreak: a systematic review of current literature

OBJECT: The novel severe acute respiratory syndrome (SARS)-CoV-2 outbreak has been declared a pandemic in March, 2020. An increasing body of evidence suggests that patients with the coronavirus disease (COVID-19) might have a heterogeneous spectrum of neurological symptoms METHODS: A systematic search of two databases was performed for studies published up to May 29th, 2020. PRISMA guidelines were followed. RESULTS: We included 19 studies evaluating 12,157 patients with laboratory-confirmed COVID-19 infections. The median age of patients was 50.3 (IQR 11.9), and the rate of male patients was 50.6% (95% CI 49.2–51.6%). The most common reported comorbidities were hypertension and diabetes (31.1%, 95% CI 30–32.3% and 13.5%, 95% CI 12.3–14.8%, respectively). Headache was reported in 7.5% of patients (95% CI 6.6–8.4%), and dizziness in 6.1% (95% CI 5.1–7.1%). Hypo/anosmia, and gustatory dysfunction were reported in 46.8 and 52.3%, of patients, respectively. Symptoms related to muscular injury ranged between 15 and 30%. Three studies reported radiological confirmed acute cerebrovascular disease in 2% of patients (95% CI 1.6–2.4%). CONCLUSIONS: These data support accumulating evidence that a significant proportion of patients with COVID-19 infection develop neurological manifestations, especially olfactory, and gustatory dysfunction. The pathophysiology of this association is under investigation and warrants additional studies, Physicians should be aware of this possible association because during the epidemic period of COVID-19, early recognition of neurologic manifestations otherwise not explained would raise the suspect of acute respiratory syndrome coronavirus 2 infection. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00415-020-09978-y) contains supplementary material, which is available to authorized users.