Plaque Psoriasis Itching May Impact HRQOL Even if Condition Improves

Despite achieving clear or almost clear skin, some patients with plaque psoriasis may experience persistent itching, impacting their health-related quality of life (HRQOL), say researchers, who recommend symptom monitoring.

The real-life findings from the single-arm, open-label, multicenter, prospective ProLOGUE study of 73 Japanese patients showed that treatment with brodalumab improved HRQOL for patients but itching prevented complete improvement.

“Itching in patients with psoriasis has not been well studied because psoriasis has historically been considered a nonpruritic disease, unlike atopic dermatitis,” described the researchers. “However, itching is one of the most burdensome symptoms associated with psoriasis and the most important factor contributing to the severity of psoriasis. Previous RCT-based findings of biologics in patients with psoriasis have indicated that improvement in itching, as well as PASI response, plays an important role in improving patient HRQoL, which is consistent with our findings in the real-life setting.”

All patients included in the study received 210 mg of brodalumab subcutaneously every day, 56 of which completed the 48 weeks of treatment. The researchers noted that there were no criteria established for concomitant or prohibited treatments.

There were 14 patients who reported a Dermatology Life Quality Index (DLQI) score of at least 2 and 13 patients with a Psoriasis Area and Severity Index (PASI) score of 0 to ≤2 (clear skin to almost-clear skin) at both checkpoints, among which the researchers found that itching was pervasive. At 48 weeks, all patients with PASI scores of 0 to ≤2 experienced itching.

“Moreover, a majority of patients with a DLQI score of ≥2 and an absolute PASI score of >0 to ≤2 had residual psoriatic lesions on the head (80.0% at week 12; 71.4% at week 48) or fingernails (80.0% at week 12), which indicates the burden of head and nail psoriasis on the HRQoL of patients with almost-clear skin,” detailed the researchers. “Indeed, nail involvement in psoriasis is quite common (48.1%), and the prevalence of fingernail psoriasis in patients who achieved clear or almost-clear skin with a DLQI score of ≥2 in the current study (28.6%-80.0%) was higher than that reported previously in patients with clear skin (1%-5%).”

Across all patients, DLQI scores dropped significantly from baseline to 12 weeks and to 48 weeks of treatment, with all subscale scores significantly decreasing. The majority of patients reported scores of 0 and 1, indicating no effect on their life at both 12 weeks (62.5%) and 48 weeks (66.2%). Treatment also led to significant increases in European Quality of Life 5-Dimension 5-Level Utility Index (EQ-5D-5L UI) scores at both 12 and 48 weeks.

The researchers flagged their inability to assess gender difference, as there were a limited number of female patients enrolled in the study; 82% of patients were male. According to the researchers, further assessment into gender differences is warranted, as DLQI and subscale scores are typically more impaired in women. The researchers noted the limited generalizability of their findings to other biologic agents outside of brodalumab.

Reference

Miyagi T, Kanai Y, Murotani K, et al. Itch as a critical factor in impaired health-related quality of life in patients with plaque psoriasis achieving clear or almost-clear skin: Analysis of the single- arm, open-label, multicenter, prospective ProLOGUE study. J Am Acad Dermatol. Published online June 22, 2022. doi: 10.1016/j.jdin.2022.06.013