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Little is known about the mental health consequences of severe COVID-19 illness because it is caused by a new coronavirus. Previous outbreaks caused by other coronaviruses (severe acute respiratory syndrome, SARS, and Middle East respiratory syndrome, MERS) may provide insights into ongoing problems after recovery from severe illness. 

Researchers looked at reports of psychiatric problems during SARS and MERS outbreaks and compared this to early data from the COVID-19 pandemic. Delirium (sudden confusion) was common while patients were in hospital with any of the coronavirus infections (SARS, MERS or COVID-19). 

Later, once patients had recovered from SARS and MERS, rates of long-term mental health problems were high. These included depression, anxiety, fatigue and post-traumatic stress disorder (PTSD). If COVID-19 follows a similar course, doctors will need to be aware of this risk over the longer term.

The studies in this review included patients who had severe illness. Mild disease might not have the same impact and more research is needed to explore the mental health impact of coronavirus that does not require hospital treatment. 

What’s the issue?

Some mental health problems and trauma are known to be linked to viral infections. During the pandemic, these reactions could relate to anxiety and social isolation during lockdown or could be a direct effect of infection on the brain. The body’s immune response to the virus is another possibility, or the effects of medical therapy during severe infection. 

Researchers want to know more about the mental health consequences of the disease in the short and long term. 

As COVID-19 is a new disease, there is little data on the mental health implications of the condition. But two previous coronavirus outbreaks in recent history – SARS and MERS – have been well-studied and may offer insights. 

What’s new?

Researchers looked at reports of psychiatric illness during and after coronavirus outbreaks of SARS and MERS, plus the early research on COVID-19. They included 65 peer-reviewed studies, mostly on SARS and MERS, plus seven early reports on COVID-19. The studies came from countries around the world including China, South Korea, France, and the UK. All of the people included in the studies had severe illness and were hospitalised. Follow up ranged from 2 months to 12 years after the initial infection.

In the short term, delirium was common and psychosis was rare: 

  • two in three COVID-19 patients in intensive care had delirium (26 of 40 patients in one study)
  • one in four patients admitted to hospital with SARS and MERS had delirium (36 of 129 patients in two studies). 
  • less than one in 100 SARS and MERS patients had psychosis (13 of 1744 patients in one study).

40 studies looked at long-term mental health problems in SARS and MERS patients. :

  • one in three (32%) had PTSD (121 of 402 patients in four studies)
  • one in five (19%) had persistent fatigue (61 of 316 patients in four studies)
  • approximately one in seven (15%) had anxiety disorders  (42 of 284 patients in three studies)
  • similarly, one in seven (15%) had depression (77 of 517 patients in five studies). 

Why is this important?

The long-term mental health implications of COVID-19 could potentially last for several years after the infection. People may struggle to return to work after recovery and their quality of life may be reduced.  

The British Thoracic Society recommends that patients hospitalised with COVID-19 are assessed for psychological symptoms four to six weeks after leaving hospital. They should then be referred to a psychiatric specialist if necessary. This research supports these guidelines and could increase awareness among doctors of the need for mental health assessments to identify depression, anxiety, PTSD and persistent fatigue. 

In the short term, delirium is associated with longer hospital stays and an increased risk of death. COVID-19 patients with delirium will need a hospital bed and reduce the capacity for new patients to be admitted. The National Institute for Health and Care Excellence (NICE) recommends that all patients admitted to hospital should be assessed for delirium. Not all NHS trusts have been doing this during the current crisis due to staff shortages. This Lancet Psychiatry paper suggests that preventing, recognising and managing delirium should be a priority. 

What’s next?

Most of the data are from the previous SARS and MERS outbreaks and it remains difficult to accurately predict the true mental health impact of COVID-19. Findings from previous coronavirus outbreaks are useful because they can help doctors prepare for the possibility of large numbers of COVID-19 patients with delirium in the short term, and longer term PTSD and anxiety. 

Many of the COVID-19 studies included were of low quality and have not yet been through the standard scientific review process. Ongoing research is needed during the pandemic to determine the true prevalence of delirium in the disease. 

This paper looked at data from patients admitted to hospital with severe infections. It is unclear to what extent these findings translate to much milder coronavirus infections. Further research should explore the psychological impact of mild cases of COVID-19 cases that do not lead to hospital admission. 

You may be interested to read

The full paper: Rogers J, and others. Psychiatric and neuropsychiatric presentations associated with severe coronavirus infections: a systematic review and meta-analysis with comparison to the COVID-19 pandemic. The Lancet Psychiatry. 2020; 7: 611–27

Brooks S, and others. The psychological impact of quarantine and how to reduce it: rapid review of the evidence. The Lancet 2020; 395: 10229, 912-920

The COVID Trauma Response Group, helping to coordinate trauma-informed responses to the COVID outbreak

Rabiee A, and others. Depressive symptoms after critical illness: a systematic review and meta-analysis. Crit Care Med. 2016; 44: 1744-1753 


Funding: The study was funded by the NIHR, Wellcome Trust, UK Medical Research Council, NIHR Biomedical Research Centre at University College London Hospitals NHS Foundation Trust, and University College London.

Conflicts of Interest: The study authors declare no conflicts of interest.

Disclaimer: NIHR Alerts are not a substitute for professional medical advice. They provide information about research which is funded or supported by the NIHR. Please note that views expressed in NIHR Alerts are those of the author(s) and reviewer(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.

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Study author

The public needs to be aware that most people will not have a mental illness after COVID-19. But a significant minority of cases might suffer mental illness following COVID-19. These people will need support.

The rates of depression and anxiety seen after SARS and MERS were not surprising, as these mental health disorders are common in the general population. The anxiety and depression recorded may not have been a result of the coronavirus infection. But we were surprised by the extremely high rate of PTSD and the persistent fatigue.

Jonathan Rogers, Wellcome Trust Clinical Training Fellow, Psychiatry, UCL


These findings seem to be in accord with what clinicians have been reporting from their own experiences with COVID-19, particularly the high rates of delirium during the acute infection, and long-term fatigue afterwards.

The authors acknowledge that the quality of studies included was either low (32/65) or moderate (30/65), so only three were of high quality. This clearly compromises the results from this meta-analysis but the authors are careful not to over-interpret them in the discussion. The assessment of psychiatric disorders in the studies was generally unsystematic and used self-report questionnaires. This can lead to over-detection of some conditions, such as depression and anxiety, particularly in subjects who have a co-morbid physical illness. It is therefore difficult to be confident that the findings robustly reflect the true situation. Nevertheless, they are probably the best available evidence to date so this meta-analysis is an important stepping stone towards understanding the psychiatric outcomes of those with COVID-19.

This research, rapidly but rigorously produced on an important area of public health, could have a significant impact on the design and delivery of mental health services as the NHS begins to return to normality. However, it also provides some reassurance that most people with Covid 19 will recover without developing psychiatric problems.

Norman Poole, Consultant Neuropsychiatrist, South West London and St George’s Mental Health NHS Trust

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