Study suggests link between severe Covid-19 and long-term mental health outcomes 16 months after illness

The findings were made after data from more than 18,000 of our CovidLife volunteers were analysed alongside volunteer data from 6 other studies.

Woman holding positive Covid-19 test

A study, published in The Lancet Public Health journal, showed that serious Covid-19 illness is linked to an increase in the risk of long-term adverse mental health effects.

The findings suggest that, on the whole, non-hospitalised patients with a Covid-19 infection were more likely to experience depressive symptoms up to 16 months after diagnosis compared to those never infected. Patients who were bedridden for seven days or more had higher rates of depression and anxiety, compared to people who were diagnosed with Covid-19 but never bedridden.

Importantly, the analysis found that symptoms of depression and anxiety were mostly reduced within two months for non-hospitalised patients with Covid-19. However, patients who were bedridden for seven days or more remained at increased risk of depression and anxiety over the 16-month study period.

The pandemic upended many aspects of daily life. It has been well-documented that social-distancing requirements and a feeling of general uncertainty has taken a toll on many people's mental health. Much less is known about the long-term mental health impacts beyond that period, particularly for non-hospitalised patients with varying degrees of illness severity.

To capture long-term mental health impacts, the researchers looked at how often symptoms of depression, anxiety, Covid-19 related distress, and poor sleep quality were found among people with and without a diagnosis of Covid-19 from 0–16 months. The analysis drew upon data from seven studies across Denmark, Estonia, Iceland, Norway, Sweden, and the UK.

Of the 247,249 people included, 9,979 (4%) were diagnosed with Covid-19 between February 2020 and August 2021. Overall, volunteers diagnosed with Covid-19 were more likely to have depression and poorer sleep quality compared to individuals who were never diagnosed. There were no overall differences between volunteers with or without Covid-19 in the rates of anxiety or Covid-related distress.

People diagnosed with Covid-19, but never bedridden due to their illness, were less likely to experience symptoms of depression and anxiety than those not diagnosed with Covid-19. The authors state that one explanation for this is could be that the return to normal lives is a relief for these individuals. However, those still not infected are still anxious about the risk of infection and being burdened by social isolation.

The research found a clear reduction in some mental health symptoms such as depression and Covid-19 related distress with time. By contrast, being bedridden for longer was consistently linked with a higher chance of mental health effects. Over 16 months, patients who were bedridden for seven days or more continued to be 50-60% more likely to experience more depression and anxiety compared to people never infected during the study period.

Our research is among the first to explore mental health symptoms after a serious Covid-19 illness in the general population up to 16 months after diagnosis. It suggests that mental health effects aren’t equal for all Covid-19 patients and that time spent bedridden is a key factor in determining the severity of the impacts on mental health. As we enter the third year of the pandemic, increased clinical vigilance of adverse mental health among the proportion of patients with a severe acute disease of Covid-19 and follow-up studies beyond the first year after infections are critical to ensure timely access to care.

Professor Unnur Anna Valdimarsdóttir

The quicker recovery from physical Covid-19 symptoms may explain in part why mental health symptoms decline at a similar rate for those with a mild infection. However, patients with severe Covid-19 often experience inflammation, which has previously been linked to chronic mental health effects, particularly depression.

“The higher occurrence of depression and anxiety among patients with Covid-19 who spent seven days or longer bedridden could be due to a combination of worrying about long-term health effects as well as the persistence of physical long Covid symptoms well beyond the illness that limit social contact and may result in a sense of helplessness. Equally, inflammatory responses among patients with a severe diagnosis may contribute to more persistent mental health symptoms. In contrast, the fact that individuals with a mild Covid-19 infection can return to normal lives sooner and only experience a benign infection likely contributes to the lower risk of negative mental health effects we observed.”

Ingibjörg Magnúsdóttir
Co-author, University of Iceland

Several limitations were noted in the study. First, individuals diagnosed with Covid-19 were slightly more likely to have past diagnoses of psychiatric disorders than individuals without a Covid-19 diagnosis. However, the absolute differences in the history of psychiatric disorders never exceeded 4% in any of the cohorts and did not impact the interpretation of the findings. Second, it reflects self-reported data of Covid-19 diagnosis and mental health effects – the coexistence of two or more conditions – that are interrelated to some extent. Third, most of the comparison group responded between April and June 2020, and responses from Covid-19 patients were accumulated between April 2020 and August 2021. This may have led to varying degrees of pandemic uncertainty that may have influenced the reporting of symptoms. Fourth, people diagnosed with Covid-19 were on average younger than those not diagnosed, indicating that some older patients with a Covid-19 diagnosis might have been missed. Furthermore, different recruitment strategies of the included cohorts impeded direct comparisons as national cohorts specifically targeted individuals tested for or diagnosed with Covid-19 in their recruitment whereas others did not.

To read the full paper visit:

Acute COVID-19 severity and mental health morbidity trajectories in patient populations of six nations: an observational study