Mortality predictors identified in patients with giant cell arteritis
medwireNews: Patients with large vessel involvement when diagnosed with biopsy-confirmed giant cell arteritis (GCA) have a substantially increased risk of death relative to patients with no large vessel involvement, Italian researchers report.
The team, from Azienda USL-IRCCS di Reggio Emilia, also found that polymyalgia rheumatica (PMR) at diagnosis and inflammation limited to the adventitia at temporal artery biopsy (TAB) “appear to identify subsets of patients with more benign disease”.
Specifically, on multivariate analysis, patients with PMR had a significant 43% lower risk of death than those with no PMR, while patients with inflammation limited to adventitia or to the adventitial vasa vasorum had a significant 69% lower risk of death than those with transmural inflammation (TMI).
There was no difference in survival, however, between patients with small vessel vasculitis and TMI, which indicates “that the patients with isolated adventitial inflammation may represent a subset of patients with less severe disease with reduced mortality”, Carlo Salvarani and co-authors remark.
By contrast, individuals with large vessel involvement had a significant 5.14-fold higher risk of death than those with no large vessel involvement.
The findings, reported in Rheumatology, are based on a retrospective analysis of 281 Italian patients (mean age 74 years at diagnosis, 72% women) with TAB-confirmed GCA, diagnosed between 1986 and 2012 who were followed up for 8.7 years, on average. During this time 121 patients died, most commonly of cardiovascular disease.
Female sex (hazard ratio [HR]=0.66), higher haemoglobin levels at diagnosis (HR=0.84) and long-term remission (HR=0.47) were all linked to reduced mortality risk on univariate analysis, but the associations were attenuated on multivariate analysis.
And the team found that there was no correlation between survival and the presence of giant cells or other histopathological findings on TAB, nor with visual loss, inflammatory markers, disease flares, hypertension and ischaemic heart disease.
The researchers note that the retrospective nature of the study may limit the interpretation of their findings and also point out that patients with large vessel involvement are less likely to be TAB positive.
Since the study only included TAB-positive patients, those with large vessel involvement diagnosed by imaging will have been excluded, which “probably influenced the risk of mortality related to [large vessel] involvement”, Salvarani et al observe.
By Laura Cowen
medwireNews is an independent medical news service provided by Springer Healthcare. © 2018 Springer Healthcare part of the Springer Nature group