Mississippi and South Carolina - 2 states with lax pandemic rules - saw anxiety and depression rise most last year, the CDC found

• US adults reported increasing levels of anxiety and depression from August to December 2020.
• The increases were correlated with rising COVID-19 cases, a new CDC report found.
• Mississippi and South Carolina saw the highest increases of anxiety and depression.

Americans reported increasing levels of anxiety and depression in tandem with rising COVID-19 cases last year.

The frequency of anxiety symptoms among US adults rose 13% from August to December 2020, while the frequency of depression symptoms rose 15%, according to a new report from the Centers for Disease Control and Prevention. The analysis drew on data from more than 1.5 million Americans who reported how frequently they experienced anxiety or depression to the US Census Bureau Household Pulse Survey.

The CDC analysis found that anxiety and depression were positively correlated with the average number of new daily COVID-19 cases. US cases rose from around 42,000 per day during a two-week period in August 2020 to around 218,000 per day during a two-week period in December 2020 - an increase of more than 400%.

Mississippi and South Carolina saw some of the highest increases of anxiety and depression during that time, while Florida and New York saw some of the smallest.

The report didn't analyze which aspects of the pandemic led to these negative mental-health outcomes, but other research has started to probe these questions.

A French study recently found that people who develop COVID-19 symptoms have a higher risk of anxiety and depression, likely because they fear getting sicker, infecting loved ones, or losing work or income. A January 2021 report from the Kaiser Family Foundation also found that isolation and job loss during the pandemic could predispose people to mental-health challenges.

One important takeaway from the CDC's findings, however, is that states in which anxiety and depression soared most weren't always the the ones with the strictest lockdowns, despite what some opponents to those measures suggested would happen. Mississippi and South Carolina never implemented mask mandates, and South Carolina allowed gatherings of up to 50 people throughout last year.

The CDC found that anxiety and depression seemed to peak over the winter. Then from December 2020 to early June 2021, the frequency of anxiety symptoms declined 27%, while the frequency of depression symptoms declined 25%.

One likely explanation for this, according to the researchers, is that from January to June, daily cases, hospitalizations, and deaths were declining. Vaccines, of course, also became widely available during that time.

But the Delta variant may have slowed or reversed this positive mental-health trend, the CDC found.

The new report underscores the need for mental-health services, they researchers added, as the pandemic continues.