Itch-related quality of life impact across 3 autoimmune blistering diseases: a retrospective cohort study

Introduction: Autoimmune blistering diseases (AIBD) produce a range of debilitating symptoms potentially greatly impacting quality of life (QoL). We sought to compare the disease-related and itch-related QoL impact between AIBD including pemphigus, bullous pemphigoid (BP), and mucous membrane pemphigoid (MMP). Methods: We performed a retrospective cohort study of patients attending a specialty Autoimmune Blistering Disease Clinic at a single academic center between July 2017 and April 2019. Patients with an established histopathologic or serological diagnosis of pemphigus, BP or MMP with mucosal and/or cutaneous lesions on clinical examination, or patient-reported QoL impact in the past week were recruited to participate. Patients completed Autoimmune Blistering Disease Quality of Life (ABQoL), Treatment of Autoimmune Blistering Disease Quality of Life (TABQoL), and ItchyQoL survey instruments, and disease severity was assessed using the Pemphigus Disease Area Index (PDAI) (pemphigus), Bullous Pemphigoid Disease Area Index (BPDAI) (BP), and Mucous Membrane Pemphigoid Disease Area Index (MMPDAI) (MMP). Statistical analyses were performed using IBM SPSS 26. Results: BP and pemphigus demonstrated similar itch-related QoL impact, greater than that of MMP. Disease severity was significantly associated with itch-related QoL in BP and pemphigus, as was use of biological/targeted therapies in BP alone. Discussion: Itch is a significant symptom in both BP and pemphigus and can negatively affect QoL. Disease severity and treatment type play a role in itch-related QoL in pemphigus and BP. Additional studies are needed to elucidate the mechanisms for itch in AIBD, particularly in pemphigus where this symptom has only recently been described.