Early-onset colorectal cancer trends and risk exposures in Ghana and the United States: A comparative ecological analysis based on Global Burden of Disease, 2023.

Abstract

e15691 Background: Early-onset colorectal cancer (EOCRC), defined as colorectal cancer (CRC) diagnosis before age 50, is increasing globally. By 2030, it is projected to become one of the leading causes of cancer-related mortality among this age group. Although rising global incidence, there is limited population-level evidence describing the national trends and associated risk exposures in low- and middle-income countries. By comparing Ghana and the United States, our study aims to assess EOCRC incidence trends and explore ecological associations with life-course risk exposures across settings with differing disease burden, surveillance capacity and screening guidelines. Methods: Country-level data on CRC incidence by year, sex and age group were obtained from the Global Burden of Disease (GBD) 2023 from 1990 to 2023. EOCRC was defined as CRC incidence among individuals aged 15-49 years, estimated by aggregating age-specific incidence rates across 5-year age groups. Temporal trends were assessed using log-linear regression models to estimate the average annual percent change (AAPC) in EOCRC incidence, with sex-stratified trends. Early-life exposures (ages 0-19) were assessed using summary exposure values (SEVs) for sub-optimal breastfeeding and child growth failure, while young-adult lifestyle risk exposures (ages 20-49) were alcohol and tobacco use, high body mass index, and poor dietary patterns. Linear regression models were used to evaluate the ecological associations of EOCRC incidence and SEVs in both countries. Results: EOCRC incidence increased in both countries, from 1.36 to 2.13 per 100,000 in Ghana and 5.46 to 7.69 per 100,000 in the U.S. Ghana experienced a higher rise (AAPC = 1.31% per year; 95% CI: 0.63-1.99) compared to the U.S. (AAPC = 0.92%; 95% CI: 0.80-1.04). Females had higher incidence in Ghana, whereas incidence remained higher among males in the U.S. In Ghana, EOCRC incidence was positively associated with tobacco use (β = 2.71; 95% CI: 2.03-3.40), low-fiber diet (β = 0.32; 95% CI: 0.24-0.39), processed meat intake (β = 0.39; 95% CI: 0.33-0.44), and suboptimal breastfeeding (β = 0.12; 95% CI: 0.10-0.15), while child growth failure was inversely associated (β = -0.50; 95% CI: -0.73 to -0.27). In contrast, no risk exposures were significantly associated in the U.S. Conclusions: Early-onset colorectal cancer is rising in Ghana and the U.S., but study findings show that patterns differ. Early-life and lifestyle exposures observed in Ghana highlight the influence of life-course factors in a broader epidemiological and geographic context. This is especially relevant where early CRC screening and surveillance are limited. As these findings are based on ecological associations, further studies of individual-level exposures are needed to complement population-level evidence and inform timely prevention strategies.