For 13% of patients, the disorders were their first diagnosis of a mental health issue.
Incidence of neurological disorders such as brain hemorrhage (0.6%), stroke (2.1%) and dementia (0.7%) was lower overall than for psychiatric disorders but the risk for brain disorders was generally higher in patients who had severe COVID-19.
The authors also examined data from more than 100,000 patients diagnosed with influenza and more than 236,000 diagnosed with any respiratory tract infection.
They found there was overall a 44% greater risk of neurological and mental health diagnoses after COVID-19 than after flu, and a 16% higher risk than with respiratory tract infections.
Paul Harrison, lead author from the University of Oxford, said that while the individual risk of neurological and psychiatric orders from COVID-19 was small, the overall effect across the global population could prove to be “substantial.”