People who have had Covid-19 are at an increased risk of mental health and neurological conditions—including seizures, dementia, psychotic disorders and brain fog—two years after infection, according to a large study published Wednesday in the Lancet Psychiatry medical journal, shedding further light on the long-term health consequences of the virus as countries around the world prepare to live with it.
An analysis of electronic health records from nearly 1.3 million people diagnosed with Covid-19 over a two-year period suggests there is an increased risk of developing conditions like dementia, seizures or epilepsy, brain fog and psychotic disorders like schizophrenia compared to people who had other respiratory infections.
The study, which used mostly U.S. health records, also found that adults have an increased risk of depression or anxiety following Covid, though this was short lived and faded after one or two months.
Children were also more likely to be diagnosed with some conditions like psychotic disorders after Covid-19, the researchers said, and were “notably at risk of epilepsy or seizures.”
Children were less likely to be diagnosed after Covid-19 than adults, however, and had no elevated risk of anxiety or depression even shortly after infection, the researchers said.
There was a greater risk of developing neurological or psychiatric conditions after the emergence of the delta variant, the researchers found, with an increased risk of anxiety (10% increased risk compared to those diagnosed before the delta wave), insomnia (19%), brain fog (38%) and seizures (26%) over the six months after Covid (dementia, with a 40% decreased risk compared to those diagnosed before the delta wave, was a notable exception).
Risks during the omicron wave were similarly elevated, the researchers said, warning that the high strain the virus puts on health systems might continue even if variants are less severe in other aspects.
It’s good news that the higher risk of anxiety and depression following Covid is short-lived in adults and absent in children, said University of Oxford researcher Dr. Max Taquet, who led the analyses. Taquet added that it is “worrying” that other conditions like dementia and seizures continue to be diagnosed at higher rates, even two years after the infection. However, Taquet said it is “important to note that the overall risk of these conditions is still low.”
Since the start of the Covid-19 pandemic, there has been growing evidence that survivors are at greater risk of developing various neurological and psychiatric conditions. This research marks the first large-scale study examining these risks on a longer time scale and sheds new light on the longer term mental and neurological health impacts. The study is also the first to examine the long-term risks to children, as well as the first to explore how these risks change with the emergence of new Covid variants. The impact of Covid on mental health goes well beyond the infection itself and factors during the pandemic including financial strains, the death or illness of loved ones, work changes and disruptions to treatment and support networks all contributed towards an upsurge in people having trouble.
92.9 million. That’s how many cases of Covid-19 have been confirmed in the U.S. since the pandemic began, according to the Centers for Disease Control and Prevention. Given the magnitude of this figure—which will not include many who did not test or were asymptomatic and does not account for more than 1 million Covid deaths—even a slightly elevated risk of psychiatric or neurological problems after infection can mean thousands or even millions of people sick. The researchers did not evaluate how long people were unwell for following diagnosis but even transitory illness could have a large impact given the numbers involved.
WHAT WE DON’T KNOW
The mechanisms underpinning the increase in psychiatric and neurological disorders following Covid aren’t known. The researchers said these remain to be determined in future studies.
By Robert Hart, Forbes Staff