Lack of follow-up after fecal occult blood testing in older adults: inappropriate screening or failure to follow up?

Risk of colorectal cancer after colonoscopy compared with flexible sigmoidoscopy or no lower endoscopy among older patients in the United States, 1998-2005

OBJECTIVE

To determine whether the risk of colorectal cancer (CRC) decreases after colonoscopy compared with sigmoidoscopy or no lower endoscopy.

PATIENTS AND METHODS

Patients 67 to 80 years old in the 5% random Medicare sample of the Surveillance, Epidemiology and End Results and Medicare-linked database were grouped into those who underwent colonoscopy or flexible sigmoidoscopy from January 1, 1998, through December 31, 2002, and those who did not undergo lower endoscopy. We excluded patients with inflammatory bowel disease, history of colon polyps, or family history of CRC. All patients were followed up until the diagnosis of CRC or carcinoma in situ, death, or December 31, 2005. The risk of CRC after colonoscopy was compared with the risk after sigmoidoscopy or no lower endoscopy. The multivariate Cox proportional hazards model was used in statistical analysis.

RESULTS

In the colonoscopy group (n=12,266), 58 CRCs (0.5%) were diagnosed during follow-up compared with 66 CRCs (1.0%) in the sigmoidoscopy group (n=6402) and 634 (1.5%) in the control group (n=41,410) (all P<.001). In the sigmoidoscopy group, 771 patients (12.0%) underwent colonoscopy within the next 12 months. In multivariate Cox regressions, colonoscopy was associated with a decreased risk of distal CRC (hazard ratio [HR], 0.266; 95% CI, 0.161-0.437) and proximal CRC (HR, 0.451; 95% CI, 0.305-0.666); sigmoidoscopy was associated with a decreased risk of distal CRC (HR, 0.409; 95% CI, 0.207-0.809) but not proximal CRC.

CONCLUSION

Among older patients, the risk of distal CRC decreased after both colonoscopy and sigmoidoscopy; the risk of proximal CRC decreased after colonoscopy but not sigmoidoscopy.

Formative evaluation of the accuracy of a clinical decision support system for cervical cancer screening

Objectives

We previously developed and reported on a prototype clinical decision support system (CDSS) for cervical cancer screening. However, the system is complex as it is based on multiple guidelines and free-text processing. Therefore, the system is susceptible to failures. This report describes a formative evaluation of the system, which is a necessary step to ensure deployment readiness of the system.

Materials and methods

Care providers who are potential end-users of the CDSS were invited to provide their recommendations for a random set of patients that represented diverse decision scenarios. The recommendations of the care providers and those generated by the CDSS were compared. Mismatched recommendations were reviewed by two independent experts.

Results

A total of 25 users participated in this study and provided recommendations for 175 cases. The CDSS had an accuracy of 87% and 12 types of CDSS errors were identified, which were mainly due to deficiencies in the system's guideline rules. When the deficiencies were rectified, the CDSS generated optimal recommendations for all failure cases, except one with incomplete documentation.

Discussion and conclusions

The crowd-sourcing approach for construction of the reference set, coupled with the expert review of mismatched recommendations, facilitated an effective evaluation and enhancement of the system, by identifying decision scenarios that were missed by the system's developers. The described methodology will be useful for other researchers who seek rapidly to evaluate and enhance the deployment readiness of complex decision support systems.

Adherence to follow-up after a positive fecal occult blood test in an organized colorectal cancer screening program in Korea, 2004-2008

BACKGROUND AND AIM

To investigate the participation rates, positivity rates, and follow-up rates from 2004 to 2008 in an organized colorectal cancer (CRC) screening program using a fecal occult blood test (FOBT) in Korea.

METHODS

The study population was men and women aged 50 years or older who were invited to participate in the National Cancer Screening Program for CRC between 1 January 2004 and 31 December 2008. We collected the FOBT results and follow-up information for the FOBT positives.

RESULTS

Participation rates increased steadily each year from 10.5% in 2004 to 21.1% in 2008. Between 2004 and 2008, FOBT positivity rates declined from 8.0% to 6.8%. Among the FOBT-positives, 61.3% of participants underwent either colonoscopy or double contrast barium enema (DCBE) in 2004, and this rate decreased to 38.6% in 2008. Age, health insurance type, and screening history were associated with adherence to follow-up test after a positive FOBT. With regard to follow-up tests, colonoscopy rates increased from 17.9% in 2004 to 27.6% in 2008, while DCBE decreased from 43.4% in 2004 to 11.0% in 2008. Colonoscopy was significantly more likely to be chosen as a follow-up test by men, participants aged 50-59 years, and National Health Insurance beneficiaries.

CONCLUSION

These findings suggest that targeting participants for follow-up, based on age and previous screening history, could be a good way to improve the follow-up rate.

Long-term outcomes following positive fecal occult blood test results in older adults: benefits and burdens

BACKGROUND

In the United States, older adults have low rates of follow-up colonoscopy after a positive fecal occult blood test (FOBT) result. The long-term outcomes of these real world practices and their associated benefits and burdens are unknown.

METHODS

Longitudinal cohort study of 212 patients 70 years or older with a positive FOBT result at 4 Veteran Affairs (VA) facilities in 2001 and followed up through 2008. We determined the frequency of downstream outcomes during the 7 years of follow-up, including procedures, colonoscopic findings, outcomes of treatment, complications, and mortality based on chart review and national VA and Medicare data. Net burden or benefit from screening and follow-up was determined according to each patient's life expectancy. Life expectancy was classified into 3 categories: best (age, 70-79 years and Charlson-Deyo comorbidity index [CCI], 0), average, and worst (age, 70-84 years and CCI, ≥4 or age, ≥85 years and CCI, ≥1).

RESULTS

Fifty-six percent of patients received follow-up colonoscopy (118 of 212), which found 34 significant adenomas and 6 cancers. Ten percent experienced complications from colonoscopy or cancer treatment (12 of 118). Forty-six percent of those without follow-up colonoscopy died of other causes within 5 years of FOBT (43 of 94), while 3 died of colorectal cancer within 5 years. Eighty-seven percent of patients with worst life expectancy experienced a net burden from screening (26 of 30) as did 70% with average life expectancy (92 of 131) and 65% with best life expectancy (35 of 51) (P = .048 for trend).

CONCLUSIONS

Over a 7-year period, older adults with best life expectancy were less likely to experience a net burden from current screening and follow-up practices than are those with worst life expectancy. The net burden could be decreased by better targeting FOBT screening and follow-up to healthy older adults.