PNAS: Stress Related to COVID-19 Pandemic Accelerates Biological Aging

The researchers analyzed data from more than 1,000 children, adolescents, and adults. Saliva samples were collected before the first lockdown in March 2020 and after the second lockdown, in winter 2021 and spring 2022.

The scientists assessed so-called epigenetic clocks — indicators based on changes in DNA methylation. These measures make it possible to determine how quickly age-related changes occur in the body. Accelerated epigenetic aging has previously been linked to an increased risk of various diseases.

The analysis showed that the rate of epigenetic aging increased across all age groups during the pandemic. The most pronounced changes were observed in people who had pre-existing health problems, lower levels of subjective well-being, or a less favorable socioeconomic status before the pandemic.

However, the association between stress and epigenetic changes was particularly strong among adolescents. Their well-being was most affected by how burdensome they perceived the pandemic to be, including restrictions on socializing with peers. The researchers found no such association among children or adults.

"Adolescents may be particularly sensitive to stress because of the changes their bodies undergo during puberty and restrictions on social interactions. In children and adults, the changes may have been linked to other consequences of the pandemic, such as reduced physical activity," the researchers said.

The authors emphasized that it remains unclear whether the observed epigenetic changes will lead to an increased risk of disease in the future. Long-term follow-up studies are needed to determine this.