The study shows that a third of COVID-19 patients experience neurological symptoms
Research into the short- and long-term effects of COVID-19 disease is ongoing. Still, scientists have found that the severe coronavirus 2 (SARS-CoV-2) with acute respiratory syndrome affects the brain, causing loss of smell and taste, dizziness, muscle pain, fatigue and other cognitive impairments. However, it remained unknown why certain people developed neurological symptoms while others did not.
Kameshwar Prasad of the Rajendra Institute of Medical Sciences in India and an international team of researchers conducted the most comprehensive systemic review and meta-analysis of previous COVID-19 cases with neurological complications of any kind.
The authors write:
“Our review shows that pre-existing neurological disorders are a common comorbidity associated with COVID-19. After hypertension and diabetes, the combined comorbidity of cardiovascular / cerebrovascular disease was the third most common comorbidity associated with COVID-19. “
They found that a third of patients with COVID-19 infection had at least one neurological manifestation. One in fifty patients has had a stroke. Age also plays a risk for people over 60 who develop neurological symptoms that are associated with increased mortality.
The team hopes their results could help clinical practice and future research understand the severity and mortality of COVID-19 infection. It could potentially help doctors treat neurological manifestations during infections and those that have persisted from long-term COVID.
The study “Frequency of Neurological Manifestations in COVID-19: A Systematic Review and Meta-Analysis of 350 Studies” is available as a preprint on the medRxiv * server while the article is being peer reviewed.
The team conducted a literature review from December 31, 2019 to December 15, 2020 reviewing COVID-19 cases. Studies were included in the review when patients were diagnosed positive with COVID-19 and had one or more neurological symptoms transiently infected. The neurological symptoms need not have been explained by an alternative health reason. The team also included cases that could potentially be cases of SARS-CoV-2 infection, but the lack of diagnostic tests.
The meta-analysis comprised 350 studies from 55 countries. A total of 20 studies in patients with COVID-19 under the age of 18 and 14 studies only included patients over 60 years of age.
145,634 patients with SARS-CoV-2 infection were included in the analysis. About 54% of the patients were male and 89% of the patients had to be hospitalized. Some patients with neurological symptoms had pre-existing medical conditions, with the highest hypertension being 26%, followed by diabetes being 14%.
Prevalence of neurological manifestations during infection
The most common neurological symptoms were fatigue (32%), muscle pain (20%), muscle pain or fatigue (31%), dizziness (7%), loss of smell (19%), loss of taste (21%), and headache (13%).
Approximately 11% of the patients had brief episodes of confusion / delirium, 7% had impaired consciousness, and 45% had restlessness.
In 33 studies, there were around 17 different neurological diagnoses in patients with COVID-19, suggesting a wide range of neurological manifestations.
Of these, 2% of the patients suffered a stroke.
The researchers also found a 24% prevalence for neuropsychiatric disorders and a 5% risk of muscle injury.
Specific neurological factors can be related to the severity of the disease
Patients with severe COVID-19 disease have been associated with skeletal muscle injury or damage, impaired consciousness, and fatigue.
However, patients with severe COVID-19 infection were less likely to experience changes in smell or taste in those with mild infection.
The results showed that about half of the patients who did not require hospitalization had a loss of smell, with 44% reporting a loss of taste. Other common symptoms were headache and muscle pain.
Age differences in neurological manifestations during infection
The team’s systemic review included 3.1.76 elderly patients with a range of ten different neurological symptoms. Older adults were more likely to have acute confusion or delirium, fatigue, muscle pain, dizziness, and headache.
Adolescent patients with SARS-CoV-2 infection reported more often fatigue or muscle pain, loss of smell or taste, headache, fatigue and seizures.
Approximately 27% of patients with COVID-19 disease and neurological symptoms died. People over 60 were significantly associated with an increased risk of dying from the disease.
* Important NOTE
medRxiv publishes preliminary scientific reports that are not peer-reviewed and therefore should not be considered conclusive, guide clinical practice / health-related behavior, or treated as established information.