Geographic variation of racial/ethnic disparities in colorectal cancer testing among medicare enrollees

Authors

  • Thomas J. Semrad MD,

    Corresponding author
    1. Division of Hematology/Oncology, Department of Internal Medicine, University of California Davis Sacramento, California
    • Division of Hematology/Oncology, Department of Internal Medicine, University of California Davis, 4501 X Street, Suite 3016, Sacramento, CA 95817
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    • Fax: (916) 734-7946

  • Daniel J. Tancredi PhD,

    1. Department of Pediatrics, Center for Healthcare Policy and Research, University of California Davis, Sacramento, California
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  • Laura-Mae Baldwin MD, MPH,

    1. Department of Family Medicine, School of Medicine, University of Washington, Seattle, Washington
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  • Pamela Green PhD,

    1. Department of Family Medicine, School of Medicine, University of Washington, Seattle, Washington
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  • Joshua J. Fenton MD, MPH

    1. Department of Family and Community Medicine, Center for Healthcare Policy and Research, University of California Davis, Sacramento, California
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Abstract

BACKGROUND:

The Medicare population has documented racial/ethnic disparities in colorectal cancer (CRC) screening, but it is unknown whether these disparities differ across geographic regions.

METHODS:

Among Medicare enrollees within 8 US states, we ascertained up-to-date CRC screening on December 31, 2003 (fecal occult blood testing in the prior year or sigmoidoscopy or colonoscopy in the prior 5 years). Logistic regression models tested for regional variation in up-to-date status among white versus different nonwhite populations (blacks, Asian/Pacific Islanders [APIs], Hispanics). We estimated regression-adjusted region-specific prevalence of up-to-date status by race/ethnicity and compared adjusted white versus nonwhite up-to-date prevalence across regions by using generalized least squares regression.

RESULTS:

White versus nonwhite up-to-date status varied significantly across regions for blacks (P = .01) and APIs (P < .001) but not Hispanics (P = .62). Whereas the white versus black differences in proportion up-to-date were greatest in Atlanta (Georgia), rural Georgia, and the San Francisco Bay Area of California (range, 10%-16% differences, blacks<whites); there were no significant white versus black differences in Connecticut, Seattle (Washington) or Iowa. Whereas APIs had significantly lower up-to-date prevalence than whites in Michigan and the California regions of San Francisco, Los Angeles, and San Jose (range, 4%-15% differences, APIs<whites), APIs in Hawaii had higher up-to-date status than whites (52% vs 38% P < .001). White versus Hispanic differences were substantial but homogeneous across regions (range, 8%-16% differences, Hispanics<whites). In contrast to nonwhites, there was little geographic variation in up-to-date status among whites.

CONCLUSIONS:

Significant geographic variation in up-to-date status among black and API Medicare enrollees is associated with heterogeneous racial/ethnic disparities for these groups across US regions. Cancer 2011. © 2011 American Cancer Society.

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