The clinical utility of telangiectasia quantification as markers of vascular disease progression in systemic sclerosis

Objectives: Telangiectasia are common in SSc. We explored the relationship between the site and quantity of telangiectasia with disease characteristics in SSc, and the agreement between patient- and physician-reported quantification of telangiectasia. Methods: A retrospective analysis of a large, cross-sectional international SSc-related vasculopathy study was undertaken, including clinician and patient assessments of telangiectasia counts (0, 1–6, 7–15 or >15) in the face, forearms and hands. Relationships between telangiectasia count at each site, demographics and clinical features including calcinosis, digital ulceration (DU) and pulmonary arterial hypertension (PAH) were examined using proportional odds logistic regression. A binary logistic regression model examined the value of telangiectasia counts on the accuracy of identifying co-existent PAH. Concordance between clinician- and patient-reported telangiectasia counts at each anatomical site was tested. Results: Higher telangiectasia counts over the face and hands were associated with higher prevalence of calcinosis, DU and PAH in univariate analysis (P < 0.001–0.003). In multivariate analysis, the presence of PAH, DU and calcinosis were associated with higher facial telangiectasia (P < 0.05). The logistic regression model for the detection of PAH was enhanced with inclusion of telangiectasia count and site (area under the precision recall curve 0.824–0.875). Strength of agreement between clinician- and patient-reported telangiectasia counts were moderate for face and forearms (kappa 0.648 and 0.605 respectively, P < 0.001) and relatively weaker for hands (kappa 0.584, P < 0.001). Conclusion: The number of telangiectasia might be considered a complementary biomarker to the presence of vascular complications of SSc including PAH, DU and calcinosis. The anatomical regions and level of instruction provided for patient-reported count of telangiectasia need further optimization to be considered reliable and feasible. In addition, future work should consider correlations with nailfold capillaroscopic patterns.