Most severe coronavirus infections do not result in mental illness. But delirium may occur in the acute stage of COVID-19, and clinicians should watch for long-term mental health effects, say researchers.

Investigators from University College London analyzed older data from 65 peer-reviewed studies of hospitalized SARS and MERS patients. These coronavirus outbreaks, while not perfect predictors, are a window into potential psychiatric outcomes from the COVID-19 pandemic, they theorized. 

The study team looked at severe cases only. Findings included acute symptoms during the illness, and long-term outcomes from two months to 12 years.

Overall, there was little evidence to suggest that mental illnesses beyond short-term delirium are typical in coronavirus illness, reported Jonathan Rogers, from University College London, UK, and colleagues. But clinicians should watch for common mental disorders such as depression, anxiety, fatigue, and PTSD in the weeks and months following recovery from severe COVID-19 infection, he added. These lingering problems have been seen in SARS and MERS patients.

In addition, a “significant minority” of MERS and SARS patients experienced delirium symptoms such as confusion, agitation and altered consciousness. Almost 28% developed confusion. What’s more, early evidence from the current pandemic suggests that delirium is similarly common in COVID-19 patients, the researchers wrote.

While mental health problems may not be a common long-term outcome from severe coronavirus, the sheer number of COVID-19 patients may predict a relatively large number of patients with these concerns. 

“To avoid a large-scale mental health crisis, we hope that people who have been hospitalized with COVID-19 will be offered support,” said senior author Professor Anthony David, also of University College London.

“Monitoring for the development of symptoms should be a routine part of the care we provide,” Rogers concluded.

The study was published in The Lancet.