Omalizumab Therapy Results in Defined Behavioural Changes and Improvements in Quality of Life in Solar Urticaria.

Abstract

Background: Solar urticaria is a rare photodermatosis in which exquisite photosensitivity can require extreme behavioural adaptations, resulting in a substantial impact on quality of life (QoL). Omalizumab therapy has been demonstrated to improve several clinical outcome measures, but the impact on behavioural measures is poorly understood. Our objectives were to examine daylight exposure behaviours and QoL measures pre- and post-omalizumab therapy.

Methods: Daylight exposure diaries were completed by n = 5 patients with solar urticaria and n = 7 healthy participants during different seasons in England, UK (51.1-53.5^oN). These incorporated a range of measures, including time spent outdoors and clothing worn, and Dermatology Life Quality Index (DLQI) data were also collected.

Results: Prior to omalizumab, patients spent less time outdoors in sunny vs. non-sunny conditions in spring (mean 10 vs. 29 min/day, p < 0.05) and less than healthy volunteers (44 min in sunny conditions/day). On omalizumab, patients increased their time outdoors in sunny conditions, reaching similar levels to healthy volunteers in spring (45 min/day) and further increasing to 85 min/day in summer. This was accompanied by fewer days with symptoms (symptoms on 75% days in spring pre-omalizumab vs. 26% days in summer on omalizumab), an apparent doubling of skin surface area exposure and substantial improvement in patients' QoL (mean past-year DLQI pre-omalizumab vs. past-week summer on omalizumab 22 vs. 5, p < 0.001).

Conclusion: Omalizumab therapy was associated with behavioural changes that increase daylight exposure, accompanied by improved QoL. This study highlights the importance of considering a range of outcome measures in assessing response to therapy.