Diagnostic Evaluation of Patients Presenting to Primary Care with Rectal Bleeding

Background: Rectal bleeding is a common, frequently benign problem that can also be an early sign of colorectal cancer. Diagnostic evaluation for rectal bleeding is complex, and clinical practice may deviate from available guidelines.

Objective: To assess the degree to which primary care physicians document risk factors for colorectal cancer among patients with rectal bleeding and order colonoscopies when indicated, and the likelihood of physicians ordering and patients receiving recommended colonoscopies based on demographic characteristics, visit patterns, and clinical presentations.

Design: Cross-sectional study using explicit chart abstraction methods.

Participants: Three hundred adults, 40-80 years of age, presenting with rectal bleeding to 15 academically affiliated primary care practices between 2012 and 2016.

Main measures: 1) The frequency at which colorectal cancer risk factors were documented in patients' charts, 2) the frequency at which physicians ordered colonoscopies and patients received them, and 3) the odds of ordering and patients receiving recommended colonoscopies based on patient demographic characteristics, visit patterns, and clinical presentations.

Key results: Risk factors for colorectal cancer were documented between 9% and 66% of the time. Most patients (89%) with rectal bleeding needed a colonoscopy according to a clinical guideline. Physicians placed colonoscopy orders for 74% of these patients, and 56% completed the colonoscopy within a year (36% within 60 days). The odds of physicians ordering recommended colonoscopies were significantly higher in patients aged 50-64 years of age than in those aged 40-50 years (OR = 2.23, 95% CI: 1.04, 4.80), and for patients whose most recent colonoscopy was 5 or more years ago (OR = 4.04, 95% CI: 1.50, 10.83). The odds of physicians ordering and patients receiving recommended colonoscopies were significantly lower for each primary care visit unrelated to rectal bleeding (OR = 0.85, 95% CI: 0.75, 0.96).

Conclusions: Diagnostic evaluation of patients presenting to primary care with rectal bleeding may be suboptimal because of inadequate risk factor assessment and prioritization of patients' other concurrent medical problems.