While neurological problems have been reported in patients following an infection with COVID-19, an analysis of over a quarter of a million patients has revealed a substantial neurological and psychiatric burden.
A good deal of evidence has revealed how as little as three months after infection with COVID-19, nearly a fifth of patients, with no prior history of mental illness, receive a new psychiatric diagnosis. Nevertheless, in order to gain a better understanding of the psychiatric and neurological sequelae of infection, longer term data are required. This need prompted a team from the Department of Psychiatry, University of Oxford, to retrospectively analyse the psychological risks associated with COVID-19 infection. In trying to assess whether the subsequent diagnosis of a psychiatric illness was specifically related to infection with COVID-19, the team used two matched control groups; those diagnosed with influenza or any respiratory tract infection during the same period of time. Their primary cohort contained patients with a confirmed diagnosis of COVID-19 and in the analysis, the team adjusted results for several established or suspected risk factors for COVID-19 e.g., age, sex, race and a number of co-morbidities e.g., hypertension, obesity etc. The outcomes of interest were any neurological or psychiatric diagnosis occurring 1–180 days after the index data, i.e., the date when the first case of COVID-19 was recorded in the US (20 Jan, 2020). COVID-19 patients were further categorised as either not hospitalised, hospitalised, those requiring admission to an intensive care unit (ICU) and those diagnosed with encephalopathy (delirium and related conditions).
The data contained 236,379 individuals with COVID-19 patients, 105579 (influenza) and 236,038 (other respiratory infection) matched controls. The average age of COVID-19 patients was 46 years (55.6% female) with White (57.2%) and Black or African American (18.8%) ethnicity accounting for the majority of individuals. The most common comorbidity was hypertension (30%) followed by obesity (18.1%). In addition, 18.7% of the cohort were hospitalised, 17.3% admitted to ICU and 17% diagnosed with encephalopathy. In the whole COVID-19 cohort, 33.6% were diagnosed with a neurological or psychiatric outcome 6 months after their initial COVID-19 infection and this was higher (46.4%) among those admitted to ICU. Diagnoses among those admitted to ICU included intracranial haemorrhage (2.66%), dementia (1.74%), Parkinsonism (0.26%), anxiety disorder (19.1%) and a psychotic disorder (2.7%). The risk of any neurological/psychiatric diagnosis was higher among those with COVID-19 compared to influenza (hazard ratio, HR = 1.44, 95% CI 1.40–1.47) and those with a respiratory tract infection (HR = 1.16, 95% CI 1.14–1.17).
The authors commented on how their findings supported the observations from previous reports on the existence of post-COVID-19 neurological/psychiatric disorders and had provided estimates of the risk for each of the diagnoses.
They concluded that in light of their findings, services should be designed and fully resourced, to deal with this anticipated increased need for support.
Taquet M et al. 6-month neurological and psychiatric outcomes in 236 379 survivors of COVID-19: a retrospective cohort study using electronic health records. Lancet Psychiatry 2021