Screening Colonoscopy for Octogenarians: Is it Indicated?

Abstract

Background: Colonoscopy is an effective means for colorectal cancer screening. Current guidelines suggest screening starts at age 50 for asymptomatic average risk person. However, it is unclear if screening may lose its clinical benefits in the elderly. Aim: To determine the prevalence of colon cancer and polyps among individuals >80 undergoing colonoscopy in a VA and a University setting. Methods: An IRB-approved retrospective review of a computer database (GI-Trac, Akron Systems) and chart review was used to identify patients ≥ 80 who had undergone either a diagnostic or screening colonoscopy between 1995 and 2004 in an outpatient setting. Patients' demographics, prior history of colon polyps or cancer, family history, clinical symptoms, ASA grade, endoscopic and pathologic findings were analyzed. Comparison is made between the symptomatic group(S), asymptomatic average risk group (AAR), and asymptomatic increased risk group (AIR) defined as prior history of colon cancer or polyps or family history of colon cancer. Results: A total of 1052 patients were included in the study. 64.6% were males, with mean age of 83 (range 80-99). 93% were ASA II, and 7% ASA III. 646 symptomatic patients had diagnostic colonoscopy. Indications include anemia (37%), minor bleeding (19%), altered bowel habits (13%), positive FOBT (8.7%), diarrhea (6.5%), active bleeding (2%) and others (4%). The prevalence of colon cancer in the S group was 3.4% (22/646). Colon cancer was detected in 10/126(8%) with minor bleeding, 2/12(17%) with weight loss, 3/50 (6%) with pain, 5/239(2%) with anemia, and 1/56(2%) with positive FOBT. Of the 232 patients in the AIR group, 6(2.6%) were found to have colon cancer (p = 0.67), the majority (5/6) have a prior history of colon cancer. No cancer (0/174) was detected in the AAR group (p = 0.007). The prevalence of benign colon polyps was 24.5% in the S group, 10.3% in the AAR group, and 66.8% in the AIR group. Conclusions: As the clinical risk/benefit ratio increases for invasive procedures in the elderly patients, screening colonoscopy does not appear to offer clinical benefit in asymptomatic average risk individual. The miss rate for undiagnosed cancer is extremely low in this group. However, the yield for colon cancer detection is higher in symptomatic individuals or asymptomatic individuals at increased risk. We support the notion that if resources are limited, screening colonoscopy is not necessary in the asymptomatic average risk individual.