The number of people experiencing anxiety and depression rose significantly in late 2020, but those numbers started to drop as Covid-19 vaccines arrived in early 2021, according to a recent Morbidity and Mortality Weekly Report from CDC.

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Severity of anxiety and depression has changed during Covid-19

For the study, CDC researchers used data from a biweekly online survey conducted from August 2020 to June 2021, analyzing 1.5 million responses regarding the severity of anxiety and depression symptoms.

The researchers found that, between August and December 2020, anxiety symptoms rose 13% and depression symptoms rose 14.8%. But between December 2020 and June 2021, anxiety symptoms decreased 26.8% and depression symptoms decreased 24.8%.

Trends in anxiety and depression symptoms at the state level were similar to the national trends, the researchers noted. New York saw one of the smallest increases in anxiety and depression scores in the second half of 2020 but also saw one of the smallest drops in 2021.

The researchers noted a strong correlation between average Covid-19 case rates and the severity of anxiety and depression symptoms reported by survey respondents. As a result, it's possible the decreasing trend of anxiety and depression symptoms may have reversed since June as the delta variant has led to a surge in Covid-19 cases, the researchers wrote.

And even as anxiety and depression scores have dropped in 2021, analyses of CDC's 2019 National Health Interview Survey data show that anxiety and depression severity scores are still 1.5 to 2 times greater than what they were in 2019.

The researchers also noted that national Covid-19 trends indicate some populations have been disproportionately affected by the disease, "which also suggests that these populations might be more vulnerable to the psychological consequences of Covid-19."

Ultimately, the study suggests "that mental health services and resources, including telehealth behavioral services, are critical during the Covid-19 pandemic, particularly among populations disproportionately affected by Covid-19," the researchers concluded. (Mueller, New York Times, 10/5; Fernandez, Axios, 10/6; Jia et al., Morbidity and Mortality Weekly Report, 10/5)