Physician Assessment of Ulcerative Colitis Activity Correlates Poorly with Endoscopic Disease Activity

Background: Subjective physician assessment is the cornerstone of routine ulcerative colitis (UC) management. Endoscopic and histologic assessment of UC provides objective measures of inflammatory disease activity. The level of agreement between physician impression of UC activity and endoscopic disease activity has not been evaluated. The aim was to assess the level of agreement between physician's clinical impression of UC disease activity and endoscopic and histologic findings of inflammation. Methods: Using the Medical Archival Retrieval System at the University of Pittsburgh Medical Center, we reviewed clinical information on all UC patients between 1995 and 2008 who had clinic visits recorded prior to colonoscopy. Clinical UC disease activity was defined by the physician's clinical impression and the endoscopic and histologic activity by colonoscopy with biopsy. The level of agreement between colonoscopy assessment of UC with histologic and clinical assessment was determined by sensitivity, specificity, positive and negative predictive values, and the kappa coefficient. Results: There were 369 UC patients who had a clinic visit proximate to a colonoscopy. The mean age of patients was 46 +/- 16 years (50% female). The performance of clinical impression in recognizing disease activity, as determined by endoscopy, was relatively poor: sensitivity = 56.0%, predictive value negative = 56.8%, kappa coefficient = 0.35. In contrast, the performance of histological evaluation in recognizing disease activity was markedly better: sensitivity = 93.5%, predictive value negative = 89.1%, kappa coefficient = 0.70. Conclusions: The physician's clinical impression of UC activity shows poor agreement with endoscopy and histology, with over one-third of patients with chronic inflammation underrecognized by clinical impression. The consequences of underestimated UC activity by clinical assessment may include undertreatment of active disease and uncontrolled chronic inflammation.