A large study published Monday in The Lancet Psychiatry has found that some COVID-19 survivors could be at risk of developing mental health issues, such as anxiety and depression, within a few months of diagnosis.

Prof. Paul Harrison of Oxford University told Reuters, “People have been worried that COVID-19 survivors will be at greater risk of mental health problems, and our findings … show this to be likely.”

The study researchers examined electronic health records of nearly 69 million American patients, of which more than 62,350 were diagnosed with COVID-19 between January and August.

The authors wrote, “Adverse mental health consequences of COVID-19, including anxiety and depression, have been widely predicted but not yet accurately measured,” adding that, “reliable estimation…requires large, well-controlled cohort studies.”

They wanted to understand whether a COVID-19 diagnosis was associated with an increased risk of mental health illness diagnoses thereafter. Also, they wanted to know whether patients with a history of mental health issues were at a higher risk of a coronavirus diagnosis.

After detailed analysis and evaluation, they found that a COVID-19 diagnosis was linked to an 18% higher risk of any psychiatric diagnosis within 90 days.

The researchers explained that the study patients had a higher risk of developing anxiety, depression, and insomnia. They also noted an increased risk of a dementia diagnosis, indicating a potential deterioration in certain brain functions, such as memory and cognition.

Neuropsychologist Dr. Wilfred Van Grop told Fox News, “I personally don’t find it all that surprising. It’s not surprising in three ways, one is: when you have a medically ill group, there’s an increased prevalence of sadness, whether it rises to a level of clinical depression or not.”

“Second, with the pandemic, anybody who’s cooped up, isolated, you get fertile ground for psychiatric illnesses like depression,” continued Dr. Van Grop, who is the director of Cognitive Assessment Group in N.Y.

“People who see COVID-19 patients, there’s so many cognitive disorders… it reminds me of people who have post-concussion syndrome,” he added, citing brain fog, neurocognitive conditions, depression, and moodiness among coronavirus patients.

Some coronavirus patients who need mechanical ventilation may experience “hypoxia,” an interruption of oxygen supply to the brain, Dr. Van Gorp explained. So, there could be consequences ranging from memory problems to dementia.

“Dementia is a syndrome and doesn’t necessarily imply a gradual onset, like Alzheimer’s,” Dr. Van Gorp said. “If somebody has a hypoxic episode that’s severe enough to cause widespread cognitive impairment, the onset would be abrupt.”

The study author wrote, “Although preliminary, our findings have implications for clinical services, and prospective cohort studies are warranted.” The article originally appeared on Fox News.