Understanding the Experiences of People Living With Chronic Pruritus of Unknown Origin: Development of a Disease Conceptual Model

OBJECTIVES: Chronic Pruritus of Unknown Origin (CPUO) remains a poorly defined condition regarding the disease and CPUO-related symptoms and impacts. This study sought to explore patients’ experience with CPUO and develop a conceptual disease model (CDM).

METHODS: Following Institutional Review Board approval, one-to-one concept elicitation (CE) interviews were conducted with US adults who have CPUO with moderate-to-severe itch. Data were analyzed using thematic analysis.

RESULTS: Twenty patients (mean age 42.7 years, 70% female) were interviewed; saturation was reached for both symptom and impact concepts. Patients reported 21 symptoms, i.e., itching (n=20), raw skin (n=17), dry skin (n=14), stinging (n=14), burning (n=14), bleeding (n=13), lesions (n=13), tingling (n=11), hot and cold sensation (n=11), skin pain (n=11), crust on skin (n=10), and darkening of the skin (n=10). Itch was reported as the worst symptom by more than half of patients (n=11), followed by skin pain (n=3), raw skin (n=2), and dry/rough skin (n=2). Six impact domains were identified including negative impact to patient’s day-to-day activities (n=18), sleep (n=16), work/school (n=14), feelings/mood (n=13), and social life (n=11). Sleep disturbance was reported as the worst impact (n=10), which included impact on sleep quality, time needed to fall asleep, and duration of sleep.

CONCLUSIONS: The concepts identified during the interviews enriched a holistic CDM and highlighted a variety of skin symptoms causing sleep disturbance and frustration to patients. As the underlying mechanism of the disease remains to be confirmed, systematic subjective assessments of patients’ quality of life in clinical trials are essential.