Starting with the first patients in Wuhan, up to today, doctors all over the world have found multiple and often prolonged neurological complications in people affected by Covid. Not only the loss of smell and taste, one of the alarm bells and widespread symptom of the infection, but also more serious problems: from encephalopathy to stroke.
To take stock of the subject will be the World Congress of Neurology, from 3 to 7 October, organized by the World Federation of Neurology in partnership with the Italian Society of Neurology (Sin), which this year will be the host.
The Italian preliminary analysis of the Neuro-COVID study, sponsored by Sin, launched in March 2020 and conducted by the University of Milan-Bicocca, the University of Milan and the Auxological Institute of Milan, will also be presented at the Congress. 50 Italian neurologies from the various regions contributed. 2500 Covid patients involved, both hospitalized and cared for at home.
The study shows that the most frequent neurological disorder is the combined alteration of smell and taste (anosmia-ageusia, about 40% of patients), the duration of this symptom lasts more than 1 month in 50% of cases. and reaches over 6 months in 20% of cases. A second disorder, very frequent (about 25% of Neuro-COVID patients), is acute encephalopathy or a state of mental confusion, loss of attention and memory, a state of agitation, up to an alteration of the state of consciousness and coma. This condition has multiple causes, starting with poor brain oxygenation (a consequence of Covid pneumonia), but in some cases it is linked to brain inflammation (encephalitis).
Many Neuro-COVID patients (about 20%) have had a concomitant ischemic stroke or soon after Covid infection, and yet the cause-and-effect link between Covid infection and stroke is still a matter of debate. Almost all of these patients have the classic vascular risk factors for stroke and from studies it appears that the infection triggered cerebral arterial thrombosis. Headache associated with Covid is frequent and not always short-lived, in fact in about 50% of cases it becomes chronic and lasts over 2 weeks, while in almost 20% of cases it lasts longer than 3 months.
Post-Covid cognitive disorders are part of the “long Covid syndrome” and have also been defined as “cognitive fog”, they are not rare (about 10% of Neuro-COVID subjects), but the extent of the disorder is almost always modest degree (does not reach the criteria of a “dementia”, but only of mild cognitive impairment) and with an important emotional as well as cognitive component. The average duration is about 3 months and resolves spontaneously within 6 months in almost all cases.
According to scientists, the main causes of neurological disorders are cerebral oxygen deficiency, cerebral inflammation or thrombosis of arteries and cerebral veins: all these alterations are possible consequences of a Covid infection.
The Neurocovid study, as part of the Congress, will be compared with similar studies promoted by other European neurological societies, with the coordination of a task force of the European Academy of Neurology, which takes care of the creation of a European registry, called ENERGY. The registry will also be compared with a similar American registry maintained by the Neurocritical Care Society and in turn called US GCS-NeuroCOVID. (HANDLE).