The COVID-19 pandemic impacted just about every part of people's lives and increased rates and severity of depression irrespective of whether they were infected or not a new study has revealed.

Quarantining, social distancing, societal disruptions and an ever-shifting, uncertain landscape of rules and restrictions and variants created stress and isolation that impacted the mental health of millions.

In a study of nearly 136,000 patients from Intermountain Health in Salt Lake City, researchers found that depressive symptoms and severity of depression were significant among all patients in the study, regardless of whether they were infected with COVID-19 or not.

"It didn't matter if a patient was positive or negative for the virus. We found increased rates of depression and depression severity across the board," said Heidi T. May, a cardiovascular epidemiologist at Intermountain Health and principal investigator of the study.

As poor mental health can impact chronic diseases, including cardiovascular disease, "screening for and treating mental health is a critical part of any overall patient care process right now. Doing so will both help patients at this moment, and protect their future health," May added.

Researchers found that depression symptoms rose significantly during the pandemic, with more than half of all patients reporting some degree of clinically-relevant depressive symptoms.

They also found that before the pandemic, about 45 per cent of patients reported some degree of depression. Starting in 2021, that changed to 55 per cent of patients showing at least some degree of depression.

"We know depression is a risk factor for chronic disease, so given these findings, it's really important to mitigate some of the effects of depression so these patients can lead healthier and happier lives right now, and in the future," said Dr May.

The study was presented at the American College of Cardiology's 2023 scientific session in the state of New Orleans on March 4.