Young-Onset CRC Mortality Disproportionately Affects Individuals With Lower Educational Attainment

The increase in young-onset colorectal cancer (CRC) mortality in the US over the past 3 decades has been largely confined to individuals with lower educational attainment, suggesting that social determinants of health play a key role in the growing disease burden, according to a research letter published last week in JAMA Network Open.¹

The Rising Burden of Young-Onset CRC and Socioeconomic Disparities

Traditionally, CRC has been considered a disease affecting older adults, but a growing body of evidence suggests a concerning shift in its epidemiology.² The 2026 American Cancer Society CRC report showed that both incidence and mortality rates have increased among younger adults in the US, raising urgent questions about underlying causes and risk factors.

While prior research has documented these rising trends, less is known about how these trends vary across socioeconomic groups.¹ Socioeconomic disparities are well documented in many areas of cancer care, including screening, access to treatment, and outcomes. However, whether these disparities extend to the observed increase in CRC mortality among younger adults has remained unclear.

To address this gap, researchers conducted a study to examine CRC mortality trends among individuals aged 25 to 49, using educational attainment as a proxy for socioeconomic status (SES). Educational attainment, a commonly used marker of SES, is a useful lens to evaluate these population-level differences, they explained.

In this cross-sectional analysis, the investigators analyzed nationwide mortality data from the National Center for Health Statistics (NCHS) spanning January 1, 1994, to December 31, 2023. The study population included individuals aged 25 to 49, with mortality rates stratified by 5-year age groups, sex, and educational attainment; individuals were categorized as receiving 12 or fewer years, 13 to 15 years, or 16 or more years of education. Corresponding population estimates were obtained from the NCHS and the US Census Bureau.

Additionally, temporal trends in CRC mortality were assessed using Joinpoint regression analysis, allowing researchers to identify changes in the direction and magnitude of trends over time. Mortality rates were age-standardized to the 2000 US population, with mortality rate ratios (RRs) and rate differences (RDs) calculated to compare individuals with the lowest (≤ 12 years) and highest (≥ 16 years) levels of educational attainment in both 1994 and 2023.

Educational Attainment Contributes to Mortality Trends in Young-Onset CRC

Between 1994 and 2023, 101,037 individuals aged 25 to 49 died from CRC in the US. The mean (SD) age at death was 43.0 (5.5) years, with men accounting for most deaths (55.4%; n = 56,007). The dataset provided a comprehensive, population-level view of CRC mortality across nearly 3 decades, enabling the researchers to make robust comparisons by sex and educational attainment.

Among men with 12 or fewer years of education, CRC death rates increased steadily throughout the study period. The annual increase accelerated from 0.6% (95% CI, 0.1%-0.8%) per year between 1994 and 2017 to 2.8% (95% CI, 1.3%-7.5%) between 2017 and 2023. In contrast, men with 16 or more years of education experienced an initial decline in mortality rates of −2.2% (95% CI, −5.7% to −0.7%) per year from 1994 to 2005, followed by an increase of 1.4% (95% CI, 0.7%-2.6%) per year through 2023.

Similarly, increases in CRC mortality among women were statistically significant, primarily among those with 15 or fewer years of education, further underscoring the role of SES in shaping outcomes.

Disparities widened considerably over time, as the RRs comparing men in the lowest vs highest education groups rose from 1.50 (95% CI, 1.32-1.69) in 1994 to 1.93 (95% CI, 1.74-2.14) in 2023, while the RD increased from 1.5 (95% CI, 1.1-1.9) to 2.8 (95% CI, 2.4-3.2) deaths per 100,000. Among women, the RRs increased from 1.55 (95% CI, 1.35-1.79) to 1.81 (95% CI, 1.62-2.04), while the RD increased from 1.3 (95% CI, 0.9-1.7) to 2.0 (95% CI, 1.6-2.4) deaths per 100,000.

“As a result, the disparity in young-onset CRC mortality among individuals with 12 years or less vs 16 or more years’ education nearly doubled over the past 3 decades,” the authors wrote.

Study Limitations and Future Directions

However, they acknowledged several limitations, including that the educational attainment data were self-reported or provided by next of kin, introducing the potential for misclassification. Changes in the composition of educational groups over time may have also influenced results. Still, the researchers expressed confidence in their findings.

“In conclusion, the increase in young-onset CRC mortality over the past decades in the US was confined largely to persons with lower educational attainment, suggesting a role of social determinants of health for the increasing burden of this disease,” they wrote.

References

1. Jemal A, Lee D, Siegel RL, Schafer EJ, Sung H, Islami F. Young-onset colorectal cancer mortality by education. JAMA Oncol. Published online April 16, 2026. doi:10.1001/jamaoncol.2026.0581
2. McCormick B. 2026 ACS report shows CRC rising in younger adults despite overall decline. AJMC^®. March 3, 2026. Accessed April 21, 2026. https://www.ajmc.com/view/2026-acs-report-shows-crc-rising-in-younger-adults-despite-overall-decline