According to a recent study, roughly 34% of COVID-19 survivors developed at least one of 14 neurological or psychiatric illnesses within six months of their COVID-19 diagnosis. This study, which examined the electronic medical records of 236,379 patients diagnosed with COVID-19, included people over 10 years of age and evaluated how many of the survivors had developed a brain and/or mental health-related diagnosis following their recovery. The most commonly diagnosed secondary illness in the study was anxiety, which impacted 17% of COVID-19 survivors, followed by mood disorders, which impacted 14% of survivors. According to the study authors, these two diagnoses did not appear to be related to how severe the recovered patient's infection had been, so even if someone was hospitalized and in intensive care, they were just as likely to be diagnosed with anxiety as a person with a mild infection.

In patients with severe infections who had been admitted into intensive care, 7% of them had a stroke within six months of their COVID-19 infections and almost 2% were diagnosed with dementia.

Other neurological symptoms found in recovered patients appeared to be much more rare, like intracranial hemorrhage (also known as bleeding within the skull) which impacted just .56% of patients. Nerve, nerve root, and plexus disorders (issues with woven spinal nerve fibers) impacted 2.85% of the patients. Brain illnesses such as dementia, stroke, and other neurological disorders were also rare in study participants.

Scientists are unsure of the causes of these neurological and psychiatric issues. Researchers noted that the impact COVID-19 is having on mental and brain health is dramatic, and treatment options should be considered for patients, as well as testing for these disorders.

This study demonstrated that COVID-19 was associated with a heightened risk of neurological and mental health outcomes, especially among patients who were hospitalized or who had encephalopathy (a brain disease or illness that alters brain function or structure).

The researchers looked at the following illnesses in patients who had been diagnosed with COVID-19 within the prior six months of their new diagnoses: intracranial haemorrhage; ischaemic stroke; parkinsonism; Guillain-Barré syndrome; nerve, nerve root, and plexus disorders; myoneural junction and muscle disease; encephalitis; dementia; psychotic, mood, and anxiety disorders (grouped and separately); substance use disorder; and insomnia.

A recently published study in the journal The Lancet reviewed patient records of over 200,000 COVID-survivors and found that a large percentage suffered some long-term neurological or psychiatric impacts. These changes were noted within six months of each patient's COVID-19 infections and were higher in this group of people who recovered from the virus than a group of people who had never been infected with COVID-19, but had been infected with influenza or other respiratory illnesses. While robust data has been produced documenting neurological issues in patients with active COVID-19 infections, this study looked at the neurological and psychiatric impacts on patients who had previously been diagnosed with the virus within 180 days.