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.