Even Mild COVID-19 May Lead to Long-Term Mental Health Issues

The COVID-19 pandemic has exacerbated the global mental health crisis, all thanks to loneliness, financial uncertainties, and grief after bereavement. But new research, shows that the virus itself may be adding to the increase in mental health issues.

According to a recent study published in The BMJ, people who contract and survive the SARS-CoV-2 virus—even just a mild form—are at a heightened risk of various mental health disorders up to a year after the acute phase of the illness. Those mental health problems include anxiety and depressive disorders, opioid use disorders, and sleep disorders, among others.

"What surprised us the most was the risk for developing mental disorders was evident even among people who had mild COVID-19 that didn't necessitate hospitalization," lead author Ziyad Al-Aly, MD, director of the Clinical Epidemiology Center at Veterans Affairs St. Louis Health Care System, told Health.

The study, conducted by researchers at the VA St. Louis Health Care System, was the first extensive look at the long-term mental health outcomes for people diagnosed with COVID-19. Study authors said that this new evidence suggests that "tackling mental health disorders among survivors of covid-19 should be a priority."

Increased Risk of Mental Health Disorders Following COVID-19 Infection

For the study, researchers used data from the Veterans Health Administration. The COVID-19 cohort included more than 153,000 patients who tested positive at least once—via polymerase chain reaction (PCR) test—between March 2020 and January 2021. The group, made up mostly of older white men with a mean age of 63 years old, did not have a history of mental health disorders for a minimum of two years before they tested positive for COVID-19.

All participants survived their bout of COVID-19, and after they recovered, researchers closely observed their mental health until November 2021, while comparing them to two control groups of people who had never been diagnosed with COVID. The first included 5.6 million patients in the VA system who did not get infected, but experienced the same pandemic challenges such as lockdowns, isolation, unemployment, and loss of loved ones. The data from the other group of 5.8 million patients was from the pre-pandemic era between March 2018 to January 2019.

Researchers found that former COVID-19 patients were 41 percent and 39 percent more likely to develop sleep disorders and depression, respectively, as compared to the control group. They were also 35 percent more likely to be diagnosed with anxiety than the latter. Those with a history of COVID-19 infection(s) were also 38 percent more likely to experience stress and adjustment disorders such as post-traumatic stress disorder (PTSD). Though people who were hospitalized were more likely to experience mental health disorders, even people with mild COVID-19 were likelier to see changes in their mental health as compared to those who didn't have COVID-19 at all.

"Most people start developing mental health symptoms in the first 90 to 120 days after their initial infection. In a few cases, it could happen eight months or up to a year later," said Dr. Al-Aly.

The good news is that only 4.4 percent to 5.6 percent of the study participants got diagnosed with depression, anxiety or stress, and adjustment disorders. "Although the odds of developing mental disorders post COVID are not astonishingly high, this paper highlights that it is still significant," Antonio Bulbena, MD, chairman of the psychiatry and forensic medicine department at The Autonomous University of Barcelona, who is not affiliated with the study, told Health.

Researchers further found that COVID patients were at an 80 percent increased risk for cognitive impairment issues such as brain fog and confusion. COVID also made people 55 percent and 65 percent more likely to be prescribed antidepressants and anxiety medications, respectively.

"I have been treating a lot of patients who were not severely ill when they had COVID but have been experiencing refractory or treatment-resistant insomnia—which is surprising," said Dr. Bulbena. "Patients with depression and anxiety are also not responding that well to medication. COVID has produced a different type of anxiety and depression that is more difficult to treat."

How COVID-19 Impacts Mental Health

According to study authors, what causes these mental health disorders following COVID-19 infection isn't entirely clear, though they do have some theories. Drs. Bulbena and Al-Aly said the SARS-CoV-2 virus could potentially cause disturbances or changes in the brain's biochemistry. COVID-19 infection is known to cause inflammation within the brain and spinal cord, and changes in the neural synapses, said Dr. Al-Aly. This might result low levels of serotonin, said Dr. Al-Aly, which is linked to depression and anxiety.

In another new study published in the journal Nature on March 7, researchers found that people who had COVID-19 experienced a greater cognitive decline associated with a decrease in the average size of their brains. They analyzed that a prior infection results in the reduction of grey matter thickness in the regions of the brain associated with smell and memory of events. The participants' brain scans further revealed that their cognitive decline was associated with the loss of brain cells in the cerebellum, which plays a vital role in mental function.

"We have known for a long time that the influenza virus also affects the brain and causes brain fog," said Dr. Bulbena. "The inflammatory ways of the coronavirus could affect different parts of the brain and damage some of its structures." But even compared to the flu, COVID-19 resulted in an increased risk of mental health outcomes, the study published in The BMJ found.

According to Dr. Bulbena—and a point that was recognized in the study itself—the biggest limitation of research is that the large cohort's participants are older adults—mainly white men. But the highest prevalence of anxiety, depression, and other mental health disorders is among young people. "Apart from the virus affecting people's neurophysiology, young people are caught less prepared as compared to older adults when it comes to dealing with uncertainties in these times," he adds. "This is a wonderful study but it represents a population that is not the main demographic who have been suffering from long COVID in terms of these emotional aspects."

When it comes to psychological factors, an individual's defense mechanisms and coping strategies—whether emotionally or problem-oriented—play a role. Young people's mechanisms for dealing with loneliness and social isolation tend to be less developed than older adults', he further explains. This could make young people more prone to substance use disorders as compared to older adults.

During the pandemic, Dr. Al-Aly and colleagues also found that COVID-19 patients were 34 percent more likely to develop opioid use disorders. This is mainly because the risk of increased opioid prescriptions also increased by 76 percent. The risk of other substance use disorders such as alcoholism could increase by 20 percent.

"Patients tend to hide their substance use habits and it goes unnoticed very often because doctors are also hesitant to bring it up. This study's findings reinforce the need for a public health policy for dealing with this problem," added Dr. Bulbena.

What to Know if You've Had COVID-19

Soon after recovering from COVID-19, early identification of any symptoms related to mental health disorders is of key importance. "Some may use our findings to gaslight or dismiss long covid as a psychosomatic condition or explain the myriad manifestations of long covid as the result of mental illness. This dismissal is contrary to scientific evidence and is harmful to patients and communities," wrote Dr. Al-Aly in an opinion piece in the BMJ.

"Health care practitioners need to recognize that the increased risk of mental health disorders for COVID patients exists. It will help in preventing far more serious problems down the road," he says.

Al-Aly recommends that while recovering from COVID, it is vital to rest and allow your body to heal to regain equilibrium post-infection. "If people who had COVID can take the time to honor their bodies and rest, they might fare better in the long term," he adds.

According to study authors, the results of this research should be used to promote awareness of the long-term mental health implications of COVID-19 infection—and to push for the early treatment of those affected.

The information in this story is accurate as of press time. However, as the situation surrounding COVID-19 continues to evolve, it's possible that some data have changed since publication. While Health is trying to keep our stories as up-to-date as possible, we also encourage readers to stay informed on news and recommendations for their own communities by using the CDC, WHO, and their local public health department as resources.