COVID-19 accounted for one in eight US deaths from March 2020 to October 2021 and was the third leading cause of death, estimates a study published yesterday in JAMA Internal Medicine.
National Cancer Institute researchers analyzed national death certificate data and provisional 2021 data from the Centers for Disease Control and Prevention (CDC). Data beyond October 2021 were excluded because they were incomplete; thus, the analysis doesn't include deaths from the Omicron variant period.
Leading cause of death in middle age
Over the entire study period, the leading causes of death were heart disease (20.1%), cancer (17.5%), COVID-19 (12.2%), accidents (6.2%), and stroke (4.7%). From March to December 2020, 2.88 million people died in the United States, slightly more than the 2.86 million who died from January to October 2021. The number of deaths rose across all age-groups except for those younger than 1 year.
In 2020, heart disease and cancer were the two top causes of death in the country, leading to 1.29 million deaths, followed by COVID-19, at 350,000 deaths.
Among people aged 55 years and older, deaths from cancer, heart disease, and COVID-19 led to the most deaths in both 2020 and 2021. Among those 85 years and older, COVID-19 was the second leading cause of death in 2020, at 110,000 (12.8%) of deaths, while it was the third leading cause in 2021, at 69,000 (8.9%) of deaths.
While COVID-19 was the fourth leading cause of death among Americans 45 to 54 years in 2020 (17,000 [10.4%]), it ranked first in 2021 (30,000 [16.8%]). In both time spans, accidents were the leading cause of death among people aged 1 to 44 years.
Relative to 2020, in 2021, COVID-19 rose from the fifth (6,100 deaths) to the second (13,000) leading cause of death among people 35 to 44 years old and took the fourth-leading spot among those 25 to 34 years (5,000) and 15 to 24 (1,100).
Indirect role in increasing deaths from other causes
"The increased ranking of COVID-19 as a leading cause of death in some age groups is consistent with a downward age shift in the distribution of COVID-19 deaths in the US in 2021 compared with 2020, perhaps driven by higher COVID-19 vaccination rates in 2021 in the oldest age groups," the researchers wrote.
The authors noted that the pandemic may also have increased deaths from other causes, such as heart disease, diabetes, Alzheimer's disease, and accidents.
"Potential explanations are fear of accessing health care or misattribution of COVID-19 deaths to other causes," they wrote. "Accidental deaths (including drug overdoses and unintentional alcohol poisoning), assault, and suicide remain major causes of death in the US, particularly in younger age groups."
