Patient perceptions of health-related quality of life in giant cell arteritis: international development of a disease-specific patient-reported outcome measure.

OBJECTIVES: GCA is a large vessel vasculitis (LVV) presenting with headache, jaw claudication, musculoskeletal and visual involvement. Current treatment is glucocorticoids and anti-IL-6 tocilizumab in refractory disease. The objective of this study was to explore the impact of GCA and its treatment on people's health-related quality of life (HRQoL), to inform the development of a disease-specific patient-reported outcome measure (PROM) for use in clinical trials and practice. METHODS: Participants from the UK and Australia, with biopsy- or imaging-confirmed GCA, were interviewed to identify salient aspects of HRQoL in relation to GCA and its treatment. Purposive sampling included a range of demographic and disease features (cranial, LVV-GCA and visual involvement). Inductive analysis identified individual themes of importance, then domains. Candidate questionnaire items were developed from the individual themes, refined by piloting, cognitive interviews and a linguistic translatability assessment. RESULTS: Thirty-six interviews were conducted to saturation with participants with GCA from the UK (25) and Australia (11). Mean age was 74 years, 23 (63.9%) were female, 13 (36.1%) had visual loss and 5 (13.9%) had LVV-GCA. Thirty-nine individual themes within five domains were identified: physical symptoms; activity of daily living and function; participation; psychological impact; and impact on sense of self and perception of health. Sixty-nine candidate items were developed from individual themes; piloting and refinement resulted in a 40-item draft questionnaire. CONCLUSION: This international qualitative study underpins the development of candidate items for a disease-specific PROM for GCA. The draft questionnaire is now ready for psychometric testing.

Jaw claudication and jaw stiffness in giant cell arteritis: secondary analysis of a qualitative research dataset.

Objective: Jaw symptoms can be a vital clue to the diagnosis of GCA. Guidelines recommend more intensive treatment if jaw claudication is present. We sought to explore how patients with GCA described their jaw symptoms. Methods: We carried out a secondary, qualitative analysis of interview data from 36 participants from the UK (n = 25) and Australia (n = 11), originally collected in order to develop a patient-reported outcome measure for GCA. In all cases, GCA had been confirmed by biopsy/imaging. Interview transcripts were organized within QSR NVivo 12 software and analysed using template analysis. Themes were refined through discussion among the research team, including a patient partner. Results: Twenty of 36 participants reported jaw symptoms associated with GCA. The median age of these 20 participants was 76.5 years; 60% were female. Five themes were identified: physical sensations; impact on function; impact on diet; symptom response with CSs; and attribution to other causes. Physical sensations included ache, cramp, stiffness and 'lockjaw'. Functional impacts included difficulty in eating/chewing, cleaning teeth, speaking or opening the mouth. Dietary impacts included switching to softer food. Response to CSs was not always immediate. Jaw symptoms were initially mis-attributed by some participants to arthritis, age or viral illnesses; or by health-care professionals to a dental cavity, ear infection or teeth-grinding. Conclusion: Jaw symptoms in GCA are diverse and can lead to diagnostic confusion with primary temporomandibular joint disorder, potentially contributing to delay in GCA diagnosis. Further research is needed to determine the relationship of jaw stiffness to jaw claudication.