Background Polymyalgia rheumatica (PMR) can present alone or with concomitant giant cell arteritis (GCA). They are closely related but implicate different treatment intensity. While PMR is diagnosed clinically, GCA should be confirmed with biopsy or vascular imaging.
Objectives To compare patient characteristics, clinical values and treatment of patients with PMR and GCA.
Methods Between 2007 and 2013, a total of 1,092 patients with diagnosis of PMR and a disease duration <2 years were recorded in the National Database of the German Collaborative Arthritis Centres. Patients with PMR (ICD-10 M35.3) were compared to patients with GCA in PMR (M31.5) with regard to patient characteristics (age, sex, smoking, BMI, education, comorbidities), markers of inflammation (ESR, CRP), and therapy. Patients aged <50 years (n=8) and with additional inflammatory rheumatic diseases (n=118) were excluded.
Results A total of 966 patients with PMR were available for analysis. 820 patients were diagnosed with PMR and 146 patients with GCA. Mean age was 70 years in both groups, mean disease duration 8 vs. 7 months for PMR and GCA, respectively. Patients with GCA were more often female (69% vs. 61%) and more frequently current smokers (21.9% vs. 10.2%). The level of education was similar, as were BMI (26.6 vs. 25.8) and comorbid conditions. 90% of all patients were treated with glucococorticoids. The average dose during the past 6 months was 19.4 mg/d (GCA) vs. 9.2 mg/d. 30% (GCA) vs. 18% were treated additionally with synthetic DMARDs, methotrexate being the most frequently used substance. In a multivariate logistic regression analysis, current smoking remained associated with an increased risk of having GCA (OR=2.8, p=0.005), dominating gender, which was not selected due to its high association with smoking status (p<0.001).
Conclusions Compared to PMR alone, patients with GCA present with a higher disease activity and a substantially higher need of immunosuppressive therapy. The association of GCA with current smoking is an additional argument for counselling patients to quit smoking if diagnosed with PMR.
Acknowledgements The database was funded by the German Federal Minister of Research from 1999 to 2007 (grant #01 GI 0344/3). Since 2007, the Working Group of the regional corporate arthritis centers and a consortium of pharmaceutical companies has been funding the National Database by an unconditional grant to the German Rheumatological Society.
Disclosure of Interest None declared