A Delphi survey of patients and clinicians on a unified and stratified approach to managing GCA-PMR spectrum disease.

This Delphi survey, involving patients, primary and secondary care clinicians, and experts was conducted to evaluate the giant cell arteritis (GCA)-polymyalgia rheumatica (PMR) spectrum disease (GPSD) and its implications. The GPSD concept proposes a unified framework for diagnosis and treatment of overlapping conditions including cranial and extracranial GCA and PMR. The survey included two rounds and addressed six propositions covering disease nomenclature, phenotypes, imaging, stratification and clinical impact. Round 1 achieved consensus across all propositions, with over 75% agreement and several items exceeding 90%. Key areas of agreement included recognition of GPSD (92%), the role of imaging in diagnosis and stratification (100%), and the need for multilevel assessment (100%). Round 2 refined and clarified questions, further strengthening consensus, with some items reaching 100% agreement. Internal consistency analysis confirmed the survey's reliability and validity for future use. The GPSD model promotes comprehensive evaluation of all phenotypes regardless of initial presentation. It advocates early specialist involvement, personalized treatment strategies and improved diagnostic tools. Imaging modalities such as ultrasound and PET are essential for detecting subclinical disease, excluding alternative diagnoses, and guiding management, especially when symptoms are ambiguous. Stratified care in PMR addresses diagnostic uncertainty and highlights emerging therapies like cytokine blockade. The model supports prospective studies using baseline imaging and stratified treatment arms to monitor disease control and long-term outcomes. By unifying fragmented care pathways and promoting a spectrum-based approach, GPSD has the potential to improve patient outcomes, reduce misdiagnosis and guide more effective therapeutic strategies across related inflammatory conditions.