BARIUM ENEMA - DETECTION OF COLONIC LESIONS IN A COMMUNITY POPULATION

OBJECTIVES. The purposes of this study were to assess the prevalence o f colonic lesions detected at barium enema in a community practice, to compare the findings at barium enema between patients who are asympto matic and have no known risk factors for colorectal cancer (screening group) and patients who have symptoms of colonic disease or have known risk factors, and to determine if a questionnaire about symptoms and risk factors is an appropriate screening tool. SUBJECTS AND METHODS. A self-administered questionnaire about colorectal symptoms and risk fa ctors was given to 1779 patients scheduled for barium enema examinatio n. On the basis of their responses, patients were divided into three g roups: screening group (asymptomatic, without risk factors), symptomat ic, and asymptomatic with risk factors. Each patient underwent a fluor oscopic barium enema. We then compared the results (number, histologic type, size of lesion(s), location in the colon, and patient's age) an d risk factors among the three groups. RESULTS. At least one lesion wi thin the colorectum was found in 166 (9%) of 1779 patients at combined proctosigmoidoscopy and barium enema, The prevalence of lesions in th e 111 patients with at least one lesion above the rectum at barium ene ma was 4% (32 of 738) for the screening group, 8% (38 of 476) for asym ptomatic patients with risk factors, and 7% (41 of 565) for symptomati c patients (p = .015 when comparing the prevalence in the screening gr oup with the prevalences in the other two groups). Twenty-nine percent of all colonic lesions were found in the screening group. Among the a symptomatic patients, risk factors that included a history of colorect al polyps and advanced age were associated with a significantly higher prevalence of colonic polyps found at barium enema. In the symptomati c group, if patients with histories of polyps were excluded, we were u nable to identify other risk factors that led to a significantly highe r prevalence of polyps. CONCLUSION. Asymptomatic patients without know n risk factors have a significantly lower prevalence of colonic polyps than either symptomatic patients or patients with risk factors alone, Despite this lower prevalence, 29% of all lesions in our series were in the screening group. Assessment of risk factors through a patient q uestionnaire was not helpful in identifying a group of patients with a higher prevalence of lesions-except for a history of polyps. Manageme nt decisions based on a patient questionnaire should be approached wit h caution. When low-risk patients are denied screening examinations, a significant number of lesions will be missed.