Complications and Laboratory Test Findings Among Patients With Generalized Pustular Psoriasis: A Retrospective Chart Review Study

Generalized pustular psoriasis (GPP) is a rare, chronic, inflammatory skin disease characterised by widespread eruption of sterile, macroscopic pustules. Patients with GPP can present with multiple comorbidities that may influence treatment. This study aimed to assess the frequency of psoriasis-related complications and non-psoriasis-related comorbidities, and clinical laboratory findings, at the time of GPP diagnosis among patients with GPP. This was a retrospective, longitudinal medical chart review of data from patients with a documented GPP diagnosis attending 29 GPP referral hospitals in Japan. Demographics and clinical characteristics were assessed at baseline (within 6 months prior to and 3 months after GPP diagnosis), including psoriasis-related complications, non-psoriasis-related comorbidities, and clinical laboratory findings. Overall, 205 patients with GPP were included; 48.3% were female, and median age at initial diagnosis was 53 years. Similar proportions of patients had mild (36.1%), moderate (30.7%) and severe (33.2%) GPP at baseline, using Japanese Dermatological Association-GPP severity criteria. Most patients (69.8%) had psoriasis-related complications at baseline, with the most common being psoriasis vulgaris (42.9%) and psoriatic arthritis (26.8%). Non-psoriasis-related comorbidities were present in 69.3% of patients with GPP at baseline, with the most common being hypertension (28.3%), dyslipidaemia (16.6%) and diabetes mellitus (16.1%). There was large variability in laboratory test values between patients. These results demonstrated that, at the time of GPP diagnosis, patients with GPP have multiple burdens of both psoriasis-related complications and non-psoriasis-related comorbidities.