First profiling of the national Swiss Clinical Quality Management giant cell arteritis and polymyalgia rheumatica registry

OBJECTIVES: To describe patient characteristics, comorbidities, diagnostic approaches, and treatment patterns in the Swiss giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) registry. METHODS: In 2020, a national GCA and PMR cohort was established within the Swiss Clinical Quality Management (SCQM) in rheumatic diseases registry. RESULTS: Between August 2020 and June 2024, 436 patients were included (337 GCA, 99 PMR). Median age was 72 years (IQR 65-77) in GCA and 71 years (IQR 63-77) in PMR; 64% and 56% were female, respectively. At diagnosis, 81% of GCA patients reported cranial symptoms, 31% visual symptoms, and 43% polymyalgic symptoms. In PMR, 95% reported shoulder girdle pain, 85% pelvic girdle pain, and 44% neck pain. Ultrasound was the most used diagnostic modality in GCA (76%), followed by PET-CT (59%) and MRI (40%). Temporal artery biopsy was performed in 29% of GCA patients, with a positivity rate of 66%. Glucocorticoids were still used by 79%, 50%, and 37% of GCA patients at 6, 12, and 24 months, respectively. Steroid-sparing agents were prescribed in 77% of patients, most commonly tocilizumab (73%). Common comorbidities included hypertension (51% GCA, 44% PMR), diabetes (15% GCA, 12% PMR), and osteoporosis (26% GCA, 15% PMR). CONCLUSIONS: The SCQM registry provides real-world data on the management of GCA-PMR spectrum disease (GPSD) patients. Imaging has largely replaced histology for GCA diagnosis. Despite 75% of GCA patients receiving tocilizumab, one-third remained on glucocorticoids beyond 2 years. Such registries are expected to optimise care for this often fragile GPSD population.