Polymyalgia Rheumatica is a Risk Factor for More Recalcitrant Disease in Giant Cell Arteritis: a Retrospective Cohort Study

Objectives: To evaluate differences in presentation and outcome of giant cell arteritis (GCA) patients with and without polymyalgia rheumatica (PMR) symptoms. Methods: Consecutive patients diagnosed with GCA between 2000 and 2020 and followed for >= 12 months at the University Hospitals Leuven (Belgium), were included retrospectively. Results: We included 398 GCA patients, of which 181 (45%) with PMR symptoms. Patients with PMR symptoms had a longer symptom duration (11 vs 6 weeks, p < 0.001). They less frequently reported fever (19% vs 28%, p = 0.030) and fatigue (52% vs 64%, p = 0.015) and tended to have less permanent vision loss (12% vs 19%, p = 0.052). There was no difference in the cumulative oral GC dose at 2 years (4.4 vs 4.3 g methylprednisolone, p = 0.571). However, those with PMR symptoms were treated with higher GC doses during subsequent follow-up (p < 0.05 from 38 months after diagnosis) and had a lower probability of stopping GC (62% vs 71%, HR 0.74 [95%CI 0.58-0.94], p = 0.018) with a longer median duration of GC treatment (29 vs 23 months, p = 0.021). In addition, presence of PMR symptoms was associated with an increased risk of relapse (64% vs 51%, HR 1.38 [95%CI 1.06-1.79], p = 0.017) with a higher number of relapses (1.47 [95%CI 1.30-1.65] vs 1.16 relapses [95%CI 1.02-1.31], p = 0.007). Patients with PMR symptoms less frequently developed thoracic aortic aneurysms during follow-up (3% vs 11%, p = 0.005). Conclusion: GCA patients with PMR symptoms had more recalcitrant disease with a higher risk of relapse and longer duration of GC treatment with need for higher GC doses.