People with mental illness are more likely to have severe outcomes from Covid. Photo / Vartika Sharma, The New York Times
People with mental illness are more likely to have severe outcomes from Covid. Photo / Vartika Sharma, The New York Times
People with psychiatric conditions are more likely to be hospitalised or die of the virus. Scientists have ideas about why that might be.
It’s been clear since the early days of the pandemic: people with mental illness are more likely to have severe outcomes from Covid. Compared withthe general population, they’re at higher risk of being hospitalised, developing long Covid or dying from an infection.
That fact puts mental illness on the same list as better-known Covid risk factors such as cardiovascular issues, chronic kidney disease and asthma.
When it comes to Covid risk, mental illness “shouldn’t be treated differently than you treat diabetes or heart disease or cancer”, said Dr Ziyad Al-Aly, the chief of research and development at the Veterans Affairs St Louis Healthcare System.
Scientists now have a better understanding of who is vulnerable. While research has linked a wide range of mental illnesses to worse Covid outcomes, experts generally believe that the risk is greatest for people with severe or unmanaged mental health conditions – suggesting that someone with schizophrenia, for example, is more likely to get sicker from Covid than someone receiving treatment for anxiety. They also have several hypotheses about why mental illness might make people more susceptible.
Many mental health conditions can lead to chronically high stress levels. And stress sabotages the immune system, flooding the body with hormones like cortisol and adrenaline. Those hormones make it harder to produce certain immune cells that are crucial for fighting off illnesses.
“The whole system is not designed to be constantly activated,” said Andrea Lynne Roberts, a researcher at Harvard University who has studied the effects of mental health conditions on Covid outcomes. That’s why people with mental illness may be more vulnerable to viral infections in general, from the common cold to Covid.
Elevated stress levels can also lead to persistently high blood pressure and more plaque deposits in the heart, contributing to cardiovascular disease – which is known to predispose people to more severe Covid infections.
High stress levels in those with mental illness weaken the immune system, raising Covid vulnerability. Photo / 123rf
Medication effects
Some antipsychotic drugs might weaken the immune system, making it harder to mount a response to a threat like a virus, said Maxime Taquet, a psychiatry researcher at the University of Oxford.
Some antidepressant medications and antipsychotics can also lead to weight gain; for that and other reasons, obesity commonly occurs in people with some mental illnesses. Data from the Centres for Disease Control and Prevention shows that obesity is tied to an increased risk of hospitalisation from a Covid infection.
Thida Thant, an assistant professor of psychiatry at the University of Colorado School of Medicine, stressed that those concerns should not dissuade people from taking medications for their mental health because the benefits of treatment far outweigh these potential risks.
Inflammation in the brain
A Covid infection raises the risk that anyone will develop a mental illness, even with no history of psychiatric disorders. That’s partly because the virus “wreaks havoc in the brain”, causing inflammation in areas that control emotion and cognition, Al-Aly said.
For people who already have mental illness, Covid can make things worse. In some patients, certain long Covid symptoms – depression, anxiety, fatigue, brain fog – might be signs that a Covid infection has exacerbated a pre-existing mental illness, Thant said.
Long Covid symptoms such as brain fog and fatigue can exacerbate existing mental health conditions. Photo / 123rf
The circumstances around mental illness
Sometimes worse outcomes from Covid have less to do with the mental illnesses themselves and more with external factors that sometimes accompany them. For example, people with mental illness are more likely to smoke and therefore have worse lung health, said Nora Volkow, director of the National Institute on Drug Abuse and a co-author of a study that showed that people with mental health disorders were significantly more likely to die or be hospitalised because of Covid.
People with severe mental illnesses are also more likely to experience poverty and may not be able to afford health care. They may also struggle to get enough sleep, maintain a balanced diet and attend to other aspects of their health, Thant said.
And the stigma around mental illness can prevent people from seeking medical care, Volkow said, which can be particularly critical when it comes to Covid. Paxlovid, an antiviral drug that slashes the risk of hospitalisation and death from the virus, needs to be taken within the first five days of symptoms, so getting a prescription early into the course of disease is essential.
But people with mental health conditions may not be able to access the care they need to get a prescription – or even know they qualify for the antiviral in the first place.
