Abstract
OBJECTIVES: To characterize a proposed clinical trial outcome measure of weekly cumulative bleeding duration from daily nosebleed diaries, termed PRO-CB (patient-reported outcome of cumulative bleeding). We also assessed cumulative weekly gushing bleeding duration (PRO-CGB) and evaluated the accuracy of patient recall on Epistaxis Severity Score (ESS) items 1-3 compared with daily diary data. METHODS: In this prospective observational study at the Toronto HHT Centre (St. Michael's Hospital, Unity Health Toronto), 23 patients from two clinical trials were observed during three-month run-in periods. Participants recorded each nosebleed episode daily, noting duration and intensity (gushing vs. non-gushing). Data were analyzed using linear mixed-effects models, correlation tests, and partial autocorrelation analyses. RESULTS: Diary compliance was 98.8%. Mean weekly PRO-CB was 71.2 min (SD 81.1); mean episode duration was 5.9 min (SD 12.6). Daily and monthly means were 10.1 min (SD 20.1) and 307.6 min (SD 311.6), respectively. Gushing episodes lasted significantly longer than non-gushing (mean difference: 5.81 min; 95% CI: 4.53-7.09). Bleeding patterns varied widely across individuals. PRO-CGB also showed inter-patient variability. PRO-CB and ESS total scores were not significantly correlated (p = 0.18, r = 0.39). ESS items 1 and 2 correlated strongly with diary data (p < 0.001); item 3 did not. Agreement was 83% for item 1% and 70% for items 2 and 3. CONCLUSION: Daily nosebleed diaries are a feasible and accurate tool for tracking epistaxis severity in HHT. Despite inter-patient variability, PRO-CB offers a meaningful outcome measure for epistaxis clinical trials. LEVEL OF EVIDENCE: 2.