Earlier this month, I presented the updated colon cancer screening guidelines and commented how virtual colonoscopy may improve screening rates due to its less invasive nature than the traditional colonoscopy. My premise was that patient discomfort served as a primary deterrent to higher rates of colonoscopy use. Data from a recently published Vanderbilt study, however, beg to differ and suggest that other factors account for the inadequate rates of colon cancer screening in the United States.
The study population was derived from the Southern Community Cohort Study (SCCS), a large research endeavor to characterize cancer trends and disparities across racial and socioeconomic backgrounds. The group comprises 51,454 patients (ages 40-79 years) collected from 48 community health centers. The exclusion criteria for this particular study included the following: race other than African-American or Caucasian; uncertainty of whether the patient has had a sigmoidoscopy or colonoscopy; and, uncertainty of family cancer history. This left 41,830 participants, who were surveyed on personal demographics, personal history of colorectal polyps, family history of colon cancer, patterns of undergoing screening endoscopy, and last visit to a health care provider.
The results show low overall colonoscopy screening rates, with African-Americans having significantly lower rates than their Caucasian counterparts. For patients with multiple first-degree relatives affected by colon cancer or a single relative diagnosed before age 50, only 27.3% of African-Americans and 43.1% of Caucasians had undergone a screening colonoscopy within the past 5 years. After adjusting for multiple demographic factors, the odds ratio for African-Americans compared to Caucasians was still low at 0.51 (0.41 for colonoscopy use within the past 10 years). There was no significant difference in flexible sigmoidoscopy use among both races.
Intererstingly, lack of physician recommendation is the main reason cited by both races for not having pursued colonoscopy screening (59.3% for African-Americans, 51.0% for Caucasians). Cost is the second most common reason for 9.1% and 17.3% of respondents, respectively. Other factors include discomfort (3.6% of Blacks and 5.6% of Whites) and fear (4.3% and 5.4%). It is possible their physicians recommended other screening tests not evaluated in the study, such as fecal occult blood or fecal immunofluorescence; however, these are only useful for detection of cancers and are not recommended for pre-malignancy. Colonoscopy and flexible sigmoidoscopy (”virtual colonoscopy” was not included in the guidelines until recently) can be used for detection of both polyps and malignant lesions, and would thus be the screening modalities of choice.
Cost and discomfort were overall minor factors in the study, but they are more prevalent in my practice. My colleagues adhere to screening guidelines quite well, which leaves me a skewed impression of why patients do not get colonoscopies. This study reminds us that “(i)ncreased efforts need to be directed at identifying and managing underserved populations at increased risk for colon cancer.” Although Katie Couric can increase overall awareness for colon cancer, it takes the doctor-patient relationship to push the agenda forward.
- Source:
- Murff HJ, Peterson NB, Fowke JH, Hargreaves M, Signorello LB, Dittus RS, Zheng W, Blot WJ. Colonoscopy screening in African Americans and Whites with affected first-degree relatives. Arch Intern Med 2008;168:625-631. DOI: 10.1001/archinte.168.6.625
