The Rising Tide of Mortality in Younger US Adults

TOPLINE:

Mortality among young adults in the United States increased since 1999, driven by overdose, suicide, and homicide, with COVID-19 exacerbating the trend. Accidental poisoning and exposure to noxious substances, such as drug overdoses, were the leading causes of death across all demographics.

METHODOLOGY:

• Researchers conducted an observational study using US mortality data (1999-2021) sourced from the US Centers for Disease Control Wide-ranging Online Data for Epidemiologic Research database.
• The study focused on younger US adults aged 18-39 years to analyze cause-specific and subgroup-specific (sex, race, and ethnicity) mortality rates.
• Overall, 15 causes with the highest crude mortality rates in 1999 and 2021 and 15 with the greatest percent increase in mortality were analyzed.
• Data spanning 22 years, including pre–COVID-19 and during COVID-19 periods, were examined to evaluate temporal trends in crude mortality rates and percent changes.
• Overall mortality trends from 1999 to 2021 were assessed using the Cochran-Armitage test.

TAKEAWAY:

• From 1999 to 2019, mortality rates in younger adults pre-pandemic increased by 10.8% (P P
• Racial disparities were noted, with American Indian or Alaskan Native populations experiencing an 87.5% increase in mortality.
• Accidental poisoning and exposure to noxious substances, such as drug overdoses, accounted for over half of the overall mortality increase in younger adults and remained the primary cause of death across all demographic subgroups examined.
• From 1999 to 2019, the leading pre-pandemic drivers of increased crude mortality rates were accidental poisoning and exposure to noxious substances (23.3 deaths/100,000), suicide (3.6 deaths/100,000), and homicide by firearms (1.6 deaths/100,000). From 1999 to 2021, the top drivers of increased crude mortality rates included accidental poisoning and exposure to noxious substances (38.3 deaths/100,000) and infectious and parasitic diseases and their sequelae, including COVID-19 (13.8 deaths/100,000). Differences were noted on the basis of race, ethnicity, and sex.

IN PRACTICE:

“Drawing attention to the troubling rise in mortality within this group may provide the impetus for further research to elucidate underlying causes of this trend, and to intervene,” the authors wrote. “Resources should be calibrated to address persisting drivers of mortality and to support this generation, who are the present and future of our nation,” they added.

SOURCE:

This study was led by Virginia Cafferky, MPH, of the Department of Epidemiology at the Boston University School of Public Health in Boston. It was published online on February 20, 2025, in Journal of Adolescent Health.

LIMITATIONS:

The reliability of race and ethnicity data varied among different groups, and the available sex data were binary, limiting the analysis of gender minorities. This study relied on death certificates, so it did not capture mortality trends among undocumented individuals and may contain inaccuracies. Additionally, the focus on singular underlying causes of death did not consider possible multiple comorbidities contributing to mortality.

DISCLOSURES:

This study was supported by the National Institute of Mental Health of the National Institutes of Health. One author was supported by the National Institutes of Health. The authors did not disclose any relevant conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.