Cost-Utility of Routine Testing in Chronic Urticaria/Angioedema: A Cohort Study.

BACKGROUND: Chronic urticaria/angioedema (CUA) guidelines recommend limiting tests to diagnose and assess prognosis, activity, and severity. Routine testing in CUA might substantially increase cost of disease without benefiting outcome. OBJECTIVE: To evaluate the utility of tests in CUA and how they influence the cost of disease. METHODS: We reviewed 725 electronic medical records of patients who were evaluated for CUA between 2010 and 2018 at a tertiary care center. The sample was gathered through the search of International Classification of Diseases Ninth and Tenth Revision codes pertaining to CUA. Analyses were made to evaluate changes in outcome for patients on whom at least 1 test was performed to evaluate CUA, the costs generated by these tests, and the tendencies to order specific tests from 2010 through 2018. RESULTS: Of 725 patients (age median, 47 years; women, 73.1%), 543 (74.8%) had at least 1 test performed. Tests had an elevated percentage of normal results (>90%). Five patients (0.9%) had a change in outcome and 8 patients were given a different diagnosis (0.1% each). Evaluation, management, and tests accounted for most of the costs. Costs remain similar between 2010-2014 (mean, $569) and 2015-2018 (mean, $569). CONCLUSIONS: In CUA, tests rarely uncover underlying conditions or lead to changes in management and outcome, but they substantially increase the costs generated by the disease. Adherence to current recommendations to limit testing might help in reducing the financial burden of CUA and improve delivery of care.