Severe COVID-19 Tied to Increased Risk for Mental Illness

New research adds to a growing body of evidence suggesting that COVID-19 infection can be hard on mental health. 

A UK study of more than 18 million adults showed an elevated rate of mental illness, including depression and serious mental illness, for up to a year following a bout of COVID-19, particularly in those with severe COVID who had not been vaccinated. 

Importantly, vaccination appeared to mitigate the adverse effects of COVID-19 on mental health, the investigators found. 

“Our results highlight the importance COVID-19 vaccination in the general population and particularly among those with mental illnesses, who may be at higher risk of both SARS-CoV-2 infection and adverse outcomes following COVID-19,” first author Venexia Walker, PhD, with University of Bristol, Bristol, United Kingdom, said in a news release. 

The study was published online on August 21 in JAMA Psychiatry.

Novel Data

“Before this study, a number of papers had looked at associations of COVID diagnosis with mental ill health, and broadly speaking, they had reported associations of different magnitudes,” study author Jonathan Sterne, with University of Bristol, noted in a journal podcast. 

“Some studies were restricted to patients who were hospitalized with COVID-19 and some not and the duration of follow-up varied. And importantly, the nature of COVID-19 changed profoundly as vaccination became available and there was little data on the impact of vaccination on associations of COVID-19 with subsequent mental ill health,” Sterne said. 

The UK study was conducted in three cohorts — a cohort of about 18.6 million people who were diagnosed with COVID-19 before a vaccine was available, a cohort of about 14 million adults who were vaccinated, and a cohort of about 3.2 million people who were unvaccinated.

The researchers compared rates of various mental illnesses after COVID-19 with rates before or without COVID-19 and by vaccination status.

Across all cohorts, rates of most mental illnesses examined were “markedly elevated” during the first month following a COVID-19 diagnosis compared with rates before or without COVID-19.

For example, the adjusted hazard ratios for depression (the most common illness) and serious mental illness in the month after COVID-19 were 1.93 and 1.49, respectively, in the prevaccination cohort and 1.79 and 1.45, respectively, in the unvaccinated cohort compared with 1.16 and 0.91 in the vaccinated cohort.

This elevation in the rate of mental illnesses was mainly seen after severe COVID-19 that led to hospitalization and remained higher for up to a year following severe COVID-19 in unvaccinated adults.

For severe COVID-19 with hospitalization, the adjusted hazard ratio for depression in the month following admission was 16.3 in the prevaccine cohort, 15.6 in the unvaccinated cohort, and 12.9 in the vaccinated cohort.

The adjusted hazard ratios for serious mental illness in the month after COVID hospitalization was 9.71 in the prevaccine cohort, 8.75 with no vaccination, and 6.52 with vaccination. 

“Incidences of other mental illnesses were broadly similar to those of depression and serious mental illness, both overall and for COVID-19 with and without hospitalization,” the authors report in their paper.

Consistent with prior research, subgroup analyzes found the association of COVID-19 and mental illness was stronger among older adults and men, with no marked differences by ethnic group.

“We should be concerned about continuing consequences in people who experienced severe COVID-19 early in the pandemic, and they may include a continuing higher incidence of mental ill health, such as depression and serious mental illness,” Sterne said in the podcast. 

In terms of ongoing booster vaccinations, “people who are advised that they are under vaccinated or recommended for further COVID-19 vaccination, should take those invitations seriously, because by preventing severe COVID-19, which is what vaccination does, you can prevent consequences such as mental illness,” Sterne added. 

The study was supported by the COVID-19 Longitudinal Health and Wellbeing National Core Study, which is funded by the Medical Research Council and National Institute for Health and Care Research. The authors had no relevant conflicts of interest.