Colorectal cancer screening, comorbidity, and follow-up in elderly patients.

OBJECTIVE: We examined the relationship between comorbid disease and performance of complete colon examination by colonoscopy or double contrast barium enema (DCBE) after positive screening fecal occult blood test (FOBT) in patients 70 years of age or older.
BACKGROUND: FOBT is an accepted form of colorectal cancer (CRC) screening. Factors that influence follow-up of positive FOBT have been largely unknown.
METHODS: Patients aged 70 years and older with positive FOBT between March 1, 2000 and Feb 28, 2001 were included in this retrospective medical record review performed at a single center. Comorbidity was measured by the Charlson Comorbidity Scale.
RESULTS: : In our sample of 266 subjects, 193 (73%) were referred for evaluation of positive FOBT and 109 (41%) underwent a colonoscopy or DCBE within 12 months. Using the Charlson score for comorbidity, 27% of our sample scored 0, 24% scored 1, and 23% scored 2 while 26% had a Charlson score of 3 or higher. There was no association between Charlson score (0, 1, 2, and > or =3) and referral for evaluation (chi test, P = 0.28) or performance of a complete colon examination (chi test, P = 0.38).
CONCLUSIONS: In this sample, only 41% of patients with positive FOBT underwent a full colon examination within 12 months of a positive FOBT. Although comorbidity burden was considerable, there was no association between comorbidity score and referral for or performance of a full colon examination. These results suggest that inappropriate patients receive CRC screening, which may contribute to delays for screening appropriate patients and diagnostic delays for others with positive screening test findings.