BACKGROUND AND PURPOSE:

• USPSTF recommends continuing colorectal cancer (CRC) screening through age 75, followed by individual decisions on screening for those over 75 | Data is limited for this age group
• Ma et al. (JAMA Oncology, 2021) examined the association of lower gastrointestinal tract screening endoscopy with the risk of CRC incidence and CRC-related mortality in older US adults

METHODS:

• Prospective cohort study
• Population
  • Health care professionals in the US
    • Nurses’ Health Study (NHS): Jan 1988 to Jun 2016
    • Health Professionals Follow-up Study (HPFS): Jan 1988 to Jan 2016
• Exposures
  • History of screening sigmoidoscopy or colonoscopy (routine/average risk or positive family history), assessed every 2 years
    • To 75 years of age
    • After 75 years of age
• Primary outcomes
  • CRC incidence
  • CRC-related mortality: Confirmed by National Death Index, medical records, and pathology reports

RESULTS:

• 56,374 participants reached 75 years of age during follow-up
  • 63.2% women
  • Incident CRC cases: 661
  • CRC-related deaths: 323
• Regardless of screening history, screening endoscopy after 75 years of age was associated with reduced risk of
  • CRC incidence (primarily distal colon and rectal)
    • Hazard ratio 0.61 (95% CI, 0.51 to 0.74)
  • CRC-related mortality
    • HR 0.60 (95% CI, 0.46 to 0.78)
• Broken down by screening history, there was still a reduced risk of CRC incidence and related mortality with screening after age 75
  • Screening endoscopy <75
    • CRC incidence: 0.67 (95% CI, 0.50 to 0.89)
    • CRC-related mortality: 0.58 (95% CI 0.38 to 0.87)
  • No screening history
    • CRC incidence: 0.51 (95% CI, 0.37 to 0.70)
    • CRC-related mortality: 0.63 (95% CI, 0.43 to 0.93)
• Screening endoscopy >75 years of age was not associated with risk reduction in CRC death among participants with
  • Cardiovascular disease: HR 1.18 (95% CI, 0.59 to 2.35)
  • Significant comorbidities: HR 1.17 (95% CI, 0.57 to 2.43)

CONCLUSION:

• Endoscopy screening for those older than 75 was associated with a reduced risk of CRC and CRC-related mortality, regardless of prior screening history
  • However, there was no risk reduction with screening after 75 if the individual had cardiovascular disease or significant comorbidities
• The results of this study support continued screening after 75 years of age for individuals without significant comorbidities
• The authors state

Given the difficulty of conducting randomized clinical trials of screening among older adults with sufficient follow-up, our data provide an important contribution in addressing this question

Our findings provide evidence for patients, physicians, and policy makers to make informed decisions about CRC screening in an older population

Learn More – Primary Sources:

Association of Screening Lower Endoscopy With Colorectal Cancer Incidence and Mortality in Adults Older Than 75 Years

Related ObG Topics:

Professional Guidelines: Colorectal Cancer Screening

What Percentage of Individuals under 50 Years of Age with Colon Cancer Have Mutations Associated with Heritable Cancer?

Is Obesity Associated with Higher Risk of Early-Onset Colorectal Cancer in Women?