Background: CSU/CIU negatively impacts different domains of patient’s health-related quality of life (HRQOL) such as sleep resulting in fatigue, daytime somnolence and lack of energy. Little information is available on the association between improvement in urticaria signs and symptoms and improvement in sleep or reduction in daytime somnolence.
Objective: To explore the correlations between the trajectories of change shown in the Weekly Urticaria Activity Score (UAS7) and two domains of the Medical Outcomes Study (MOS) Sleep Scale (daytime somnolence and sleep disturbance) across 40 weeks in two phase III trials.
Methods: Data were obtained from ASTERIA I and GLACIAL trials, investigating the efficacy of omalizumab in patients with refractory CSU/CIU. Patient-reported outcome (PRO) data were collected at baseline and Weeks 4, 12, 24, and 40. Urticaria signs (wheals) and symptoms (itching) were measured using the UAS7. Effects on sleep were measured using two domains of the MOS Sleep Scale (a 12-item PRO comprising six domains that measure key aspects of sleep): daytime somnolence and sleep disturbance. Data were analysed using latent growth modelling (LGM) wherein individual patient slopes of change and intercepts for UAS7 and MOS daytime somnolence and sleep disturbance were correlated for each patient.
Results: In both trials, mean baseline UAS7 score was 30 out of 42, mean MOS somnolence score was 40 out of 100 and mean sleep disturbance score was 47 out of 100. These scores decreased to 10 for UAS7, 25 for MOS somnolence and 29 for sleep disturbance at Week 24. LGM analysis found that changes in UAS7 and MOS daytime somnolence were correlated at 0.67 (ASTERIA I) and 0.72 (GLACIAL) indicating moderate-to-strong correspondence between changes in signs and symptoms and daytime somnolence. This positive correlation suggests that knowledge of a patient’s signs and symptoms of urticaria provides good insight into the extent of daytime somnolence. Changes in the UAS7 and MOS sleep disturbance subscale were correlated at 0.53 (ASTERIA I) and 0.59 (GLACIAL). A patient’s UAS7 score yields moderate insight into their sleep disturbance and vice-versa.
Conclusion: These results indicate reliable empirical evidence that sleep is negatively affected by urticaria signs and symptoms. Further, these results appear to be the first to use data from all assessment points simultaneously to demonstrate that improvements in urticaria result in substantial reductions in daytime somnolence and sleep disturbance.
