When evaluating the symptoms of chronic spontaneous urticaria (CSU) over time, several tools are available for use in both the clinical trial and clinical practice settings. It is important to note that measuring treatment success goes beyond symptom relief and should also encompass quality of life (QOL) and patient productivity in work and school.

There are various tools used to measure the severity of CSU, with some being more useful in the clinical trial setting while others may be more practical in clinical practice. Most clinical trials in the United States and Europe assess chronic urticaria using the weekly Urticaria Activity Score (UAS7), which is the sum of a patient’s wheals and itch scores over 7 consecutive days. The UAS7 looks at the number of wheals and the severity of itch, and the patient will fill out a diary every day to obtain a weekly score. This assessment is considered a good predictor of a drug’s efficacy and is the gold standard for measuring treatment success with a new therapy. However, outside of a clinical trial setting, it is very difficult to get patients to fill out this type of symptom diary on a daily basis.

For this reason, there are also tools such as the Urticaria Control Test (UCT), which is a simple, 4-question test that can be administered in the clinic. The UCT provides a reasonable assessment of how well a patient is doing without the burden of their having to fill out a diary every day. The UCT looks back at the previous 4 weeks and asks patients questions about the symptomatic, therapeutic, and overall control of their disease, as well as its impact on QOL. If the combined score is greater than 12, then we can say that a patient’s urticaria is pretty well controlled. If it is less than 12, then obviously it is not as well controlled.

The UAS7 score remains the gold standard that regulatory agencies use when evaluating a drug therapy, or they may use one of the components of the UAS7: the weekly Itch Severity Scale (ISS7). Clinical trials may use either the UAS7 or the ISS7, but they also typically look at QOL indices to ensure that decreases in urticaria and angioedema during treatment with a given therapy translate to improvements in QOL. That is especially relevant for trials of biologics. To prove that a biologic is worth using in patients with CSU, it is necessary to show not only that the disease itself is improved but also that there are improvements in QOL and other measures, such as increases in productivity and decreases in work and school loss.

These assessments can also be important for discussions with patients about goal setting. Of course, the goal is always to see if a patient can be hive free, but that is just not possible in some patients. Or it may be possible, but you would have to use so many medications to reach this goal that medication adverse consequences would affect the patient’s QOL. In such cases, it may not be worth adding these other drugs. We often ask our patients, “What level of disease control makes you feel better and is acceptable?” They may not be able to get rid of every hive, so it is important to find out what is comfortable for them and what types of things we need to do to achieve their goal.