A team from Albuquerque, New Mexico, USA, compared the cost-effectiveness of two screening programs for colorectal cancer, based on a single or repeated colonoscopy.
The cost-effectiveness of screening was analyzed with a computer model of a Markov process.
In the model, a hypothetical population of 100,000 subjects aged 50 years underwent a single colonoscopy at the age of 65 years or repeated colonoscopy every 10 years starting at the age of 50.
Transition rates were estimated from US vital statistics and cancer statistics, and published data on polyp incidence, patient compliance, and efficacy of colonoscopy plus polypectomy in cancer prevention.
Costs of screening and cancer care were estimated from the 1998 Medicare reimbursement data.
|Single colonoscopy was most cost-effective after the age of 70.
| Archives of Internal Medicine |
Compared with no screening, the incremental cost-effectiveness ratio of a single or repeated colonoscopy amounted to $2981 or to $10,983 per life year saved, respectively.
A single colonoscopy was found to save most life years if done at the age of 60, but became most cost-effective after the age of 70.
The researchers found that, depending on the level of compliance, repeated colonoscopies saved 2- to 3-times more lives than a screening program based on a single colonoscopy.
Dr Amnon Sonnenberg, of the Department of Veterans Affairs Medical Center, Albuquerque, said on behalf of the group, "A repeated colonoscopy every 10 years offers better prevention against colorectal cancer and represents a medically more desirable screening option, than a single colonoscopy does."
"If high costs or low patient compliance renders this option not feasible, a single colonoscopy at the age of 65 would represent a highly cost-effective alternative," it was concluded.