A new large-scale analysis of US patient data has found nearly one in five people are diagnosed with a psychiatric illness within three months of a positive COVID-19 test. The Oxford University led study suggests recovered COVID patients are twice as likely to suffer from anxiety, depression, or insomnia compared to patients with other diseases.
“People have been worried that COVID-19 survivors will be at greater risk of mental health problems, and our findings in a large and detailed study show this to be likely,” explains Paul Harrison, lead author on the new study.
Analyzing around 70 million US electronic health records, the Oxford team homed in on more than 62,000 COVID-19 patients. In the 90 days following a positive COVID-19 test 18.1 percent of patients were diagnosed with some kind of psychiatric illness. These mental health conditions included anxiety disorders, insomnia and dementia.
To quantify the specific association between COVID-19 and the psychiatric conditions, the researchers created a cohort of matched controls. These were groups of patients recently diagnosed with other conditions such as influenza, skin infections, kidney stones and bone fractures.
Obviously battling with any kind of illness presents mental health challenges, so the goal here was to understand whether COVID-19 specifically increases a person’s risk of these psychiatric conditions compared to other health problems. The results affirmed that compared to a variety of other medical events, COVID-19 patients are at a notably higher risk of suffering from mental health issues.
David Curtis, from University College London, calls the results “broadly plausible” but notes it is unclear exactly what they mean.
“It’s difficult to judge the importance of these findings,” says Curtis, who did not work on the new study. “These psychiatric diagnoses get made quite commonly when people present to doctors and it may be unsurprising that this happens a bit more often in people with COVID-19, who may understandably have been worried that they might become seriously unwell and who will also have had to endure a period of isolation.”
Simon Wessely, an expert in emergency preparedness and response from King’s College London, suggests these findings do fit with observations seen in previous pandemics. However, he also says it is possible the viral infection may be somewhat causally connected to these mental health conditions.
“COVID-19 affects the central nervous system, and so might directly increase subsequent disorders,” says Wessely. “But this research confirms that is not the whole story, and that this risk is increased by previous ill health.”
In the new study, published in The Lancet, the researchers note there currently is no known physiological mechanism to causally connect COVID-19 with an increased risk of psychiatric disorders. But, the researchers also clearly state the effects detected in the study are large enough to demand urgent investigation.
“Since our severity and contextual factors hypotheses cannot explain most of the associations, it is necessary to explore the cause of the particular effect of COVID-19 on the risk of psychiatric disorder,” the Oxford team writes in the new study. “Despite various speculations, the underlying mechanisms are unknown and require urgent investigation. The relationship between the severity of illness (as proxied by inpatient admission) and psychiatric outcomes, albeit modest, might represent a dose-response relationship, suggesting that the association might at least partly be mediated by biological factors directly related to COVID-19 (eg. viral load, breathlessness, or the nature of the immune response).”
Ultimately, Harrison suggests the new study can be primarily interpreted as a call to action for healthcare professionals around the world. Regardless of the cause it seems clear COVID-19 will inevitably trigger higher rates of mental illness in the coming months and years, and healthcare services must be prepared.
“Services need to be ready to provide care, especially since our results are likely to be underestimates of the actual number of cases,” says Harrison. “We urgently need research to investigate the causes and identify new treatments.”
The new study was published in The Lancet.
Source: University of Oxford