Today in Annals of Internal Medicine, researchers show that, compared to 2020, mortality rates due to COVID-19 infections among young adults increased significantly in 2021, suggesting younger people had lower vaccine uptake and adhered to fewer COVID precautions than older adults in the United States
To understand the age shift that occurred among COVID-19 deaths in the United States, researchers used Years of Life Lost (YLL) rather than mortality during March to December of 2020 and March to December of 2021. The study was based on data from the CDC WONDER (Centers for Disease Control and Prevention Wide-ranging ONline Data for Epidemiologic Research), with life expectancies based on the World Health Organization global health estimate from 2017.
During those two periods, the median age of COVID-19 deaths decreased from 78 years in 2020 to 69 years in 2021, and YLL due to COVID-19 increased to 7.4% more years of life lost in the second pandemic year due to a 35.7% increase in YLL per COVID-19 death. Despite those changes, there were 20.8% less COVID-19 deaths in 2021 versus 2020.
"Further investigation should determine the extent to which this downward age shift in COVID-19 mortality is attributable to high early-pandemic COVID-19 death rates among older adults (for example, involving nursing homes and long-term care facilities), relatively higher vaccine coverage and adherence with nonpharmaceutical interventions among older versus younger adults later in the pandemic, age-related risk differences associated with coronavirus variant viruses, or other mechanisms," the authors said.
The analysis showed other changes to YLL during 2020 to 2021: YLL and deaths due to unintentional injuries increased considerably, owing in part to record-high drug overdose deaths, up 15% (nearly 14,000 deaths) in 2021 compared with 2020, the authors said.
"A shift in COVID-19 mortality to relatively younger people in the second pandemic year contributed to markedly increased premature mortality from this increasingly preventable death," said corresponding author Mark Czeisler, PhD, medical student at Harvard Medical School, in a press release. "Understanding the factors that contribute to this age shift is critical as we continue developing our knowledge of the COVID-19 pandemic."