No randomized, controlled trials of screening colonoscopy have been completed, and ongoing trials exclude persons aged 75 years or older.
The Medicare program, however, reimburses screening colonoscopy without an upper age limit.
Dr Xabier García-Albéniz and colleagues evaluated the effectiveness and safety of screening colonoscopy to prevent colorectal cancer in persons aged 70 to 74 and those aged 75 to 79 years.
|The 8-year risk for colorectal cancer was 2% in the screening colonoscopy group|
|Annals of Internal Medicine|
The research team performed a large-scale, population-based, prospective study.
The observational data were used to emulate a target trial with 2 groups, including colonoscopy screening and no screening.
The team evaluated 1,355,692 Medicare beneficiaries aged 70 to 79 years at average risk for colorectal cancer who used Medicare preventive services, and had no previous diagnostic or surveillance colonoscopies in the past 5 years.
The researchers examined 8-year risk for colorectal cancer, and 30-day risk for adverse events.
In beneficiaries aged 70 to 74 years, the team found that the 8-year risk for colorectal cancer was 2% in the screening colonoscopy group, and almost 3% in the no-screening group.
Among those aged 75 to 79 years, the 8-year risk for colorectal cancer was about 3% in the screening colonoscopy group and in the no-screening group.
The team noted that the excess 30-day risk for any adverse event in the colonoscopy group was 6 events per 1000 individuals in the 70- to 74-year age group, and 10 per 1000 in the 75- to 79-year age group.
Dr García-Albéniz's team comments, "Screening colonoscopy may have had a modest benefit in preventing colorectal cancer in beneficiaries aged 70 to 74 years, and a smaller benefit in older beneficiaries."
"The risk for adverse events was low but greater among older persons."