Trends in colorectal cancer testing among Medicare subpopulations.
BACKGROUND
In 1998, Medicare initiated universal coverage for colorectal cancer (CRC) screening via fecal occult blood testing (FOBT) and sigmoidoscopy. In mid-2001, universal coverage was advanced to screening colonoscopy. This study sought to determine whether trends in CRC testing differed among racial/ethnic, age, or gender subgroups of the Medicare population.


METHODS
In 2006, claims from 1995 to 2003 were analyzed for annual 5% random samples of fee-for-service Medicare enrollees living in Surveillance, Epidemiology, and End Results (SEER) regions to calculate the annual, age-standardized percentages of subjects who received FOBT, sigmoidoscopy, or colonoscopy. Logistic regression then modeled trends in annual test use within racial/ethnic, age, and gender subgroups across three Medicare coverage periods (precoverage [1995-1997]; limited coverage [1998-mid-2001]; and full coverage [mid-2001-2003]).


RESULTS
The annual use of FOBT and sigmoidoscopy declined from 1995 to 2003 in all racial/ethnic groups, but the relative decline in sigmoidoscopy use was greater among whites compared to nonwhites. In contrast, colonoscopy use increased substantially in all racial/ethnic groups. However, relative to the precoverage period among whites, the full-coverage period was associated with significantly greater colonoscopy use among whites (OR=2.14; 95% CI=2.09, 2.19) than blacks (OR=1.86; 95% CI=1.75, 1.96); Asian/Pacific Islanders (OR=1.73; 95% CI=1.62, 1.86); or Hispanics (OR=1.65; 95% CI=1.49, 1.81). The use of colonoscopy during the full-coverage period was also differentially greater among enrollees aged <80 years. CRC testing trends were similar among male and female enrollees.


CONCLUSIONS
Colonoscopy is supplanting sigmoidoscopy as a CRC test among Medicare enrollees, while FOBT use is in decline. The transition from sigmoidoscopy to colonoscopy has occurred more quickly among white than nonwhite Medicare enrollees.
Fenton
Joshua J
JJ
Department of Family and Community Medicine, University of California Davis, 4860 Y Street, Suite 2300, Sacramento CA 95817, USA. Joshua.fenton@ucdmc.ucdavis.edu
Cai
Yong
Y
Green
Pamela
P
Beckett
Laurel A
LA
Franks
Peter
P
Baldwin
Laura-Mae
LM
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control; D016001:Confidence Intervals; D005260:Female; D006297:Health Services Accessibility / Q000706:statistics & numerical data* / Q000639:trends; D054624:Health Status Disparities; D006801:Humans; D016015:Logistic Models; D008297:Male; D008403:Mass Screening / Q000379:methods / Q000706:statistics & numerical data* / Q000639:trends*; D006278:Medicare; D009780:Occult Blood; D016017:Odds Ratio; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data*; D010865:Pilot Projects; D011159:Population Surveillance; D012042:Registries; D018426:SEER Program; D012812:Sigmoidoscopy; D014481:United States / Q000453:epidemiology