Adaptation and Validation of the Korean Version of the Urticaria Control Test and Its Correlation With Salivary Cortisone

Abstract

Purpose: Frequent changes in chronic urticaria (CU) activity over time can cause psychological stress, which also serves as a trigger of CU. To measure the control status of CU, the Urticaria Control Test (UCT) was developed in Germany. This study aimed to investigate the validity, reliability and responsiveness to changes in CU for the Korean version of the UCT (K-UCT) and its relation with salivary cortisol and cortisone levels.

Methods: Linguistic adaptation of the UCT into Korean was conducted. A total of 96 CU patients were enrolled, and 80 of them completed the study. The K-UCT and other outcome scores for CU were measured and repeated after 4 weeks of treatment. Control status was classified by physicians into well-controlled, partly-controlled, and uncontrolled CU. Salivary cortisol and cortisone were measured by liquid chromatography-tandem mass spectrometry.

Results: Excellent internal consistency and intra-class reliability were obtained. Strong correlations between the K-UCT and disease severity, reflected in the Urticaria Activity Score (UAS)/global assessment of urticaria control by physicians/patient assessment of symptom severity/CU-specific quality of life were noted. K-UCT scores ≥12 were found to be optimal for determining well-controlled CU (sensitivity, 75.0%; specificity, 758%; area under the curve, 0.824). Perceived stress scale scores were significantly correlated with the UAS and the K-UCT. Salivary cortisone levels were significantly correlated with K-UCT (r = 0.308, P = 0.009) and differed significantly according to control status determined by a K-UCT ≥12.

Conclusions: This study demonstrated that the K-UCT can be a valid instrument with which to gauge CU control status in Korean patients. Further studies are needed to validate salivary cortisone as a biomarker for CU control.

Keywords: Chronic urticaria; Korea; linguistic adaptation; urticaria control test; validation.

Fig. 1. Changes in patient distributions according to control status after 4 weeks of treatment.

Fig. 2. Changes in CU related scores after 4-week treatment. Positive values mean increasing scores at visit 2. On the contrary, negative scores represent decreasing scores at visit 2.

CU, chronic urticaria; UAS-Ye, Urticaria Activity Score revised by Ye et al.; UAS7, Urticaria Activity Score Over 7 Days; CU-QoL, chronic urticaria-specific quality of life; K-UCT, Korean version of Urticaria Control Test; VAS, visual analogue scale; PSS, Perceived Stress Scale; CESD, Center for Epidemiologic Studies-Depression. ^*P < 0.05, ^†P < 0.001.

Fig. 3. Structural equation modeling to estimate relationships among K-UCT and UAS7/CU-QoL/salivary cortisone levels. The K-UCT was found to be a significant predictor of salivary cortisone levels (β = 0.278, P = 0.016) and CU-QoL (β = 0.501, P < 0.001). The UAS7 negatively impacted both K-UCT (β = −0.303, P = 0.008) and CU-QoL (β = −0.231, P = 0.021). The numbers on the arrows indicate the regression coefficient (β) of the structural equation model. Positive numbers mean a positive correlation between 2 factors, whereas negative numbers mean negative correlations. The direction of the arrows represents cause and effect.

K-UCT, Korean version of Urticaria Control Test; CU, chronic urticaria; UAS7, Urticaria Activity Score Over 7 Days; CU-QoL, chronic urticaria-specific quality of life. ^*P < 0.05, ^†P < 0.01, ^‡P < 0.001.