SAN DIEGO — Male sex and advanced age are both risk factors for the development of early-onset colorectal cancer, according to results of a case-control study presented at Digestive Disease Week.
Additionally, weight loss of at least 5 kg may be a warning sign for early-onset colorectal cancer, according to the data.
Eric Low, MD, MPH, of the University of California San Diego, said that incidence and mortality are rising in the United States among people younger than 50 years, but there have not been many clues as to why that is happening.
“Despite well-established risk factors for colorectal cancer overall, it’s not well understood what’s driving this rise among our young adult population,” Low said in his presentation. “This is in large part due to the fact that risk factors associated with early-onset colorectal cancer have not been widely studied.”
Researchers conducted the study to identify potential risk factors for early-onset CRC using a national sample of veterans aged 18 to 49 years who underwent colonoscopy between 1999 and 2014. They compared 651 patients with CRC with 67,416 controls who were CRC free at baseline and through 3 years of follow-up.
Compared with control individuals, patients with CRC were more likely to be older, male, current smokers, non-aspirin users and have a lower BMI (all P < .05).
After adjusting for several factors, researchers found that increasing age (OR = 1.05; 95% CI, 1.03–1.07) and male sex (OR = 2.21; 95% CI, 1.68–2.91) were linked with increased risk for early-onset CRC. Low said these findings were consistent with current CRC literature. Aspirin use and overweight or obesity were associated with a decreased risk for early-onset CRC.
In a post-hoc analysis, Low and colleagues identified a potential early clinical finding that weight loss could be associated with early-onset CRC. Patients with CRC had a negative average 10-year change in weight while controls had a positive average change (P < .0001). Researchers determined that 17.5% of patients with CRC lost at least 5 kg in the 5 years prior to baseline colonoscopy compared with 8.7% of the controls (OR = 2.23; 95% CI, 1.76–2.83).
“We believe that more intense efforts are required to identify potential causal factors and clinical signs that should trigger work-up for early-onset colorectal cancer,” Low said. “Hopefully, elucidating these risk factors may serve to clarify which individuals under age 50 may benefit from screening and lead to early detection and prevention of colorectal cancer.” – by Alex Young
Low E, et al. Abstract 982. Presented at: Digestive Disease Week; May 18-21, 2019; San Diego.
Disclosures: Low reports no relevant financial disclosures. Please see the meeting disclosure index for all other authors’ relevant financial disclosures.