Assessing disease activity in ulcerative colitis

BACKGROUND: We aimed to determine the optimal approach to assess disease activity (i.e., biological inflammation) in ulcerative colitis (UC) by comparing patients' and physicians' rating of the disease. METHODS: This was a prospective, multicenter, double-cohort study. The first cohort was composed of 94 children with UC (parent proxy when required) and their physicians who provided independent clinical report and global assessment of disease, rated on a 100 mm visual analog scale. Constructs of disease activity (including mucosal inflammation, laboratory tests, Mayo score, and the Pediatric UC Activity Index), were scored by an independent blinded physician and used to compare validity of the assessment. Of the 94 children, 43 were seen at a follow-up visit and provided a global rating of change in disease activity. To ascertain whether age influences assessment accuracy, a second cohort of 86 adult UC patients were analyzed in a similar way. RESULTS: In both cohorts the physician global assessment had higher correlations with all constructs of disease activity than did the patient' global assessment (for colonoscopic score r = 0.76 vs. r = 0.29, P = 0.002). Even with abdominal pain, a subjective item, the physician's rating had higher correlation than the patient's rating. Similarly, the physician rating of change better reflected change in disease activity than that of the patient rating. CONCLUSIONS: For indirect measurement of biological activity on the basis of symptoms and signs, clinician assessments are superior to those of patients. Patient assessments, physician assessments, and direct measurement of disease activity provide complementary information in clinical research.