Findings from a single-centre study in the United States has supported recommendations to lower the colorectal cancer screening age from 50 to 45, with the searchers suggesting that screening colonoscopy outcomes were slightly less common in people aged 45 to 49 compared with those in the 50–54 age group.
Only the risk for any adenoma was significantly lower in the younger group (35.4% vs 40.8%; adjusted risk ratio [aRR] 0.86, 95% CI 0.82-0.90), reported Jeffrey Lee, MD, MPH, of Kaiser Permanente Northern California in Pleasanton, and colleagues in JAMA.
They said none of the other colonoscopy findings differed significantly between the two age groups:
• Advanced adenoma (3.8% vs 4.1%; aRR 0.90, 95% CI 0.75-1.09)
• Advanced serrated lesion (1.5% vs 1.8%; aRR 0.85, 95% CI 0.63-1.14)
• Any sessile serrated lesion (10.2% vs 10.4%; aRR 0.98, 95% CI 0.88-1.10)
• Colorectal cancer (0.1% vs 0.1%; aRR 0.56, 95% CI 0.15-2.07)
There were no significant differences in neoplasia prevalence between the age groups by sex.
The findings suggest there’s no need to reduce adenoma or sessile serrated lesion detection rate benchmarks because of the infusion of younger patients into the screening pool, Lee told MedPage Today.
“Doctors should not be worried that just because we’ve infused a bunch of young adults recently (into the screening pool) … that we have to change those targets … because we find similar rates regardless of age,” he said.
Veroushka Ballester, MD, a spokesperson for the American Gastroenterological Association who wasn’t involved with the research, said the findings support the 2021 change in US Preventive Services Task Force (USPSTF) guidance that colorectal cancer screening should begin at 45 instead of 50 for average-risk patients.
“Although screening colonoscopy outcomes were generally slightly less frequent among the younger group compared with the older group, by showing comparable detection rates of advanced lesions and sessile serrated lesions between the 45-49 and 50-54 age groups, the study reinforces the rationale behind the revised screening age recommendations,” Ballester told MedPage Today.
Aasma Shaukat, MD, MPH, a gastroenterologist at NYU Langone Health in New York, who also wasn’t involved with the study, said the findings are in line with other work showing younger adults have a slightly lower prevalence of adenomas compared with older people.
Shaukat said the current findings are “expected”, but further research is needed to show more definitively whether lowering the colorectal cancer screening age to 45 was the right thing to do.
“Say 10 years go by and we actually see a reduction in colon cancer incidence and mortality compared to 45- to 49-year-olds who aren’t screened or weren’t being screened,” she said. “Those kinds of data will tell us if it were a correct decision.”
The USPSTF issued the change in 2021 partly because of rising rates of colorectal cancer among young people. “It’s incredibly alarming because we don't know why it’s happening,” said Lee.
At the same time, there have been few reports on screening colonoscopy neoplasia yields among younger adults since the guideline change, Lee and colleagues noted.
The researchers examined data from screening colonoscopies that took place at Kaiser Permanente Northern California between 2021 and 2024. A total of 12 031 patients had screening colonoscopy; 4 380 were ages 45-49 and 7 651 were 50-54.
Women made up 47.3% of the overall cohort and 42.8% of participants were white. Median body mass index was 26.5 and 24% had
a history of smoking.
Lee and colleagues cautioned that Asian Americans made up 30.4% of the study cohort, which is higher than the general population and may influence the generalisability of the findings.
Medpage Today article – Study Supports Lowering Colon Cancer Screening Age (Open access)
See more from MedicalBrief archives:
Updated US guidelines for colorectal cancer screenings
ACS recommends earlier colorectal cancer screening