A large new study offers the first investigation into persistent mental health issues in non-hospitalized COVID-19 patients up to 16 months after an initial infection. The findings reveal COVID-19 led to a higher risk of depression and anxiety following acute disease if the illness was severe enough to keep patients in bed for over seven days.
“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,” explained Unnur Anna Valdimarsdóttir, an author on the new study. “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.”
The study looked at data from nearly 250,000 people spanning Sweden, Iceland, Denmark, Estonia, Norway and the U.K. Just under 10,000 of those received a positive COVID-19 diagnosis and the researchers were most interested in tracking persistent symptoms of depression, anxiety, COVID-19-related distress, and poor sleep quality.
In general, the study found COVID-19 led to an 18 percent increase in the prevalence of depression and a 13 percent increase in poor sleep quality compared to a cohort of people without a history of SARS-CoV-2 infection. Rates of anxiety or COVID-related distress were generally similar between infected and non-infected cohorts.
The study also found the severity of the initial disease significantly correlated with the persistence of mental health problems. Around a quarter of those with COVID-19 experienced disease severe enough to keep them in bed for seven days or more. Anxiety and depression was up to 60 percent more prevalent in those bedridden for a week from COVID-19 compared to the uninfected control group.
Those with mild or asymptomatic COVID-19 were seen to recover swiftly from any signs of mental health distress within one or two months of their acute illness. Interestingly, the long-term follow-up found those mild or asymptomatic cases ultimately showed a lower prevalence of mental health symptoms compared to the uninfected cohort. Co-senior author Fang Fang, from the Karolinska Institutet, hypothesizes this finding could be underpinned by a sense of relief in those only experiencing a mild infection.
“It is possible that the completion of low- or asymptomatic COVID-19 infection results in a certain relief among these individuals who can now return to their normal lives,” said Fang. “This could be one of the reasons for the lower prevalence of mental health symptoms observed in this group relative to those in the population who are still worried about being infected and therefore avoiding social interactions.”
The researchers do indicate it is also possible pre-existing psychological and physiological vulnerabilities contribute to both the severity of acute COVID-19 and the persistence of mental health problems. As co-author Aniko Lovik pointed out, the findings in the study are likely due to some kind of combination of inflammation triggered by the coronavirus infection and psychological worries or anxieties.
“While we cannot fully explain these associations, some contributing factors may be a combination of worrying about long-term health effects as well as persistence of physical symptoms that limit social contact and fuel a sense of helplessness,” said Lovik. “It is also possible that severe COVID-19 triggers inflammatory processes that have previously been linked to increased risk of mental ill-health.”
The new findings follow another recent study that looked at persistent mental health issues in 150,000 American COVID-19 patients up to one year after initial infection. That study similarly found COVID-19 patients were 50 percent more likely to experience mental health problems compared to those without COVID.
Co-author on the new study Unnur Anna Valdimarsdóttir said although these findings indicate mild COVID-19 cases may be unlikely to experience persistent, long-term mental health issues, doctors and patients should remain vigilant as researchers continue to understand the chronic effects of this new disease.
“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,” added Valdimarsdóttir.
The new study was published in the journal The Lancet Public Health.
Sources: Karolinska Institutet, The Lancet