NEW YORK (Reuters Health) – As prevention for colorectal cancer, colonoscopy once every 10 years saves more lives at a lower cost than chemoprevention with a daily dose of aspirin, researchers report in the January issue of Gastroenterology.
Dr. Amnon Sonnenberg, from the Department of Veterans Affairs Medical Center, Albuquerque, New Mexico, and colleagues constructed a hypothetical cohort of 100,000 subjects, 50 years of age, and followed them until death. The research team looked at four strategies: no intervention; colonoscopy once every 10 years, and every 3 years for those with polyps; aspirin 325 mg/day; and a combination of aspirin and colonoscopy.
The expected number of colorectal cancers per 100,000 subjects is 5904, the researchers report. According to the results of a Markov model, compared with no intervention, colonoscopy at 75% efficacy prevented 4428 cancers, saving 7951 life-years at an incremental cost-effectiveness ratio (ICER) of $10,983 per life-year saved.
Aspirin at 50% efficacy, compared with no intervention, prevented 2952 colorectal cancers and saved 5301 life-years with an ICER of $47,249 per life-year saved, they found.
The cost of aspirin therapy, including the cost of aspirin-related complications, was $172 per patient per year. "Varying the annual aspirin-related costs between $50 and $200 results in ICER changes between $4617 and $57,080, with the two strategies breaking even at $70," Dr. Sonnenberg's team writes.
Compared with colonoscopy alone, the ICER for the combined strategy of colonoscopy plus aspirin was $227,607 per life-year saved.
Dr. Sonnenberg and colleagues conclude that "the high cost of chemoprevention and its relatively low efficacy render screening colonoscopy the more cost-effective option to reduce morbidity and mortality related to colorectal cancer."
"Chemoprevention used in addition to endoscopic screening provides a viable strategy to save more lives than through colonoscopy screening alone, although this benefit is associated with an ICER that may be prohibitively high for most healthcare systems," they add.
"When compared with other medical practices, the combination of screening colonoscopy and aspirin may represent a cost-effective option, particularly in those already taking aspirin for other reasons," Dr. Dawn Provenzale, from Duke University Medical School, Durham, North Carolina, comments in a journal editorial.