The mental health impact of the COVID-19 pandemic has been acknowledged by several experts, and even the World Health Organisation (WHO). A substantial study in the US has now found that there is a 18% probability of a person with COVID-19 developing a psychiatric illness within 14 to 90 days of the diagnosis.

The study, published in The Lancet Psychiatry on November 9, was funded by National Institute for Health Research, and used data from 69.8 million individuals of whom 69,354 were diagnosed with COVID-19. Of these, 44,779 had no previous diagnoses of psychiatric illness. The researchers compared whether the diagnosis of COVID-19 was associated with higher rates of psychiatric illness diagnoses, compared to other health ailments.

The study found that the probability of being diagnosed with any psychiatric illness in 14 to 90 days of the COVID-19 diagnosis was 18.1%, including 5.8% being a first-time diagnosis. “The most common psychiatric diagnosis after COVID-19 diagnosis was anxiety disorder (12·8%), followed by mood disorders (9·9%),” the study said. Depressive episode was found to be the most common first diagnosis of a mood disorder. “The rate of first or relapsed psychotic disorder diagnosis after COVID-19 diagnosis was 0·9%,” it added.

Among anxiety disorders, adjustment disorder, generalised anxiety disorder, and, to a lesser extent, post-traumatic stress disorder and panic disorder were found to be the most common.

Meanwhile, the probability of a first-ever diagnosis of a mood disorder within 90 days of COVID-19 diagnosis was 2%, and the same for insomnia was 1.9%. “Around 60% of the insomnia diagnoses were not accompanied by a concurrent diagnosis of an anxiety disorder,” the study found.

Incidentally, the study also revealed that diagnosis of a psychiatric disorder the previous year was associated with a higher risk – 65% – of a COVID-19 diagnosis too. “This risk was independent of known physical health risk factors for COVID-19, but we cannot exclude possible residual confounding by socioeconomic factors,” the researchers said.

The researchers also said that there is a likelihood of a more severe COVID-19 infection and an increased rate of a psychiatric diagnosis.

According to Michael Bloomfield, a consultant psychiatrist at University College London, quoted by Reuters, the relationship between COVID-19 and a mental health issue is probably due to a combination of pandemic-related psychological stressors as well as physical effects of the illness itself.

Simon Wessely, regius professor of psychiatry at King’s College London added that COVID-19 affects the central nervous system, and therefore, could directly increase the risk of subsequent disorders.

Meanwhile experts told BBC that further research was needed before drawing conclusions. Jo Daniels from the University of Bath pointed out that psychological outcomes are common in those who go through any physical health problems, and that being acutely or chronically ill is simply a difficult experience.

Experts in Karnataka had earlier told TNM that they were seeing patients who had recovered from COVID-19 develop anxiety, PTSD and other mental health issues post recovery.

“Often we see chronic stress can lead to reduction of serotonin levels and this can lead to biological depression and anxiety. So, these people have to seek professional help. Maybe only 30% of people recovering from COVID-19 who face mental health issues may need to seek out professional help and there should not be any stigma surrounding this,” Dr Rajani P, Deputy Director, Mental Health, Karnataka Department of Health and Family Welfare, had told Soumya Chatterjee for TNM.

Earlier this month, the Union government had issued guidelines for COVID-19 facilities to have provision for psychiatric consultation as well, thus acknowledging that the pandemic has raised mental health concerns.