Itch improvement has a major and comparable effect on the Dermatology Life Quality Index in psoriasis and atopic dermatitis patients

Abstract Background Itch is known to have a particularly high impact on psoriasis (PsO) and atopic dermatitis (AD) patients' quality of life. Although AD therapies have exhibited a high efficacy when it comes to itch control, itch control with PsO therapies is not as well documented. Objectives The aim of this post‐hoc analysis is to better understand the impact of itch on the patients' quality of life in PsO as well as AD by providing a pairwise correlation between itch improvement and patients' quality of life and determine the predictive factors in patients achieving Dermatology Life Quality Index score of 0 or 1 DLQI (0/1). Methods Three phase III clinical studies, one in PsO and two in AD, were assessed. Pairwise correlations between objective improvement of visible signs of disease, quality of life, and itch intensity were investigated at 16 weeks of treatment. Predictive analyses methods were applied on the data to assess the impact of clinical and itch improvement on the DLQI improvement. Results This study shows that change in itch from baseline in AD and PsO patients correlate to change in DLQI from baseline. Change in itch from baseline was found to be the most important factor in predicting DLQI (0/1). Conclusions These results highlight the necessity to study itch in both PsO and AD clinical trials, and it is recommended that itch may be considered a coprimary or at minimum a secondary efficacy end‐point in all such clinical studies.