Cost-utility of one-time colonoscopic screening for colorectal cancer at various ages

OBJECTIVE: One-time colonoscopy has been recommended as a possible colorect al cancer (CRC) screening strategy. Because the incidence of colorectal neo plasia increases with age, the effectiveness and cost of this strategy depe nd on the age at which screening occurs. The purpose of this study was to i nvestigate the age-dependent cost-utility of one-time colonoscopic screenin g. METHODS: We constructed a computer simulation model of the natural history of colorectal neoplasia. This model was used to compare the cost-utility of no screening and age-based strategies employing one-time colonoscopic scre ening (age ranges evaluated: 45-49, 50-54, 55-59, and 60-64 yr). RESULTS:We determined that one-time colonoscopic screening in men age <60 y r and in women age <65 yr dominates never screening and screening at older ages. For both sexes, one-time colonoscopic screening between 50 and 54 yr of age is associated with a marginal cost-utility of less than $10,000 per additional quality-adjusted life-year compared to screening between 55 and 60 yr of age. Onetime colonoscopic screening between 45 and 49 yr of age is either dominated (women) or associated with a marginal cost-utility of $69 ,000/per quality-adjusted life-year (men) compared to screening between 50 and 54 yr of age. The marginal cost-utility of one-time colonoscopic screen ing is relatively insensitive to plausible changes in the cost of colonosco py, the cost of CRC treatment, the sensitivity of colonoscopy for colorecta l neoplasia, the utility values representing the morbidity associated with the CRC-related health states, and the discount rate. CONCLUSIONS: One-time colonoscopic screening between 50 and 54 yr of age is cost-effective compared to no screening and screening at older ages in bot h men and women. Screening in men between 45 and 49 yr of age may be cost-e ffective compared to screening between 50 and 54 yr of age depending on soc ietal willingness to pay. (C) 2000 by Am. Coll. of Gastroenterology).