Increase in screening for colorectal cancer in older Americans: results from a national survey.

OBJECTIVES: To compare the proportions of the U.S. population aged 65 and older who underwent tests for colorectal cancer (CRC) in 2000 and 2005 to examine the effect of the change in Medicare reimbursement for screening colonoscopy that occurred in 2001.

DESIGN: National population-based survey.

SETTING: United States.

PARTICIPANTS: A total of 6,035 respondents to the 2000 National Health Interview Survey (NHIS) and 5,490 respondents to the 2005 NHIS aged 65 and older.

MEASUREMENTS: A questionnaire was used to assess self-reports of testing (colonoscopy, sigmoidoscopy, or home fecal occult blood test (FOBT)) for CRC. Estimates for the U.S. population were extrapolated from the survey results. To account for the complex sampling design, SUDAAN was used to calculate population sizes and proportions.

RESULTS: In U.S. adults aged 65 and older, the proportion reporting up-to-date CRC testing increased from 39.5% in 2000 to 47.1% in 2005. By 2005, endoscopy had become more common than home FOBT for CRC screening in older adults. In 2000 and in 2005, a higher proportion of men than women were screened across all age groups and for all screening modalities. The proportion screened declined with older age.

CONCLUSION: Substantial increases in CRC testing, particularly colonoscopy, followed changes in Medicare reimbursement for screening colonoscopy in adults aged 65 and older. Although nearly half of older adults were up to date with CRC tests, differences remained in the use of screening according to age and sex within this age group.