Background/purpose: Elevated levels of C-reactive protein (CRP) in systemic sclerosis (SSc) have been linked to early inflammatory stages of the disease. This study has been designed to investigate CRP levels longitudinally in a cohort of SSc patients and to correlate these findings with comorbidities and disease characteristics. Methods: In this retrospective study, patients with SSc treated at the outpatient clinic of the Department of Rheumatology and Clinical Immunology, University Medical Center Freiburg, were analyzed. Only patients with at least three consecutive visits and at least 1 year follow-up were included in this study. CRP serum levels were measured at every visit and categorized as positive if CRP concentrations were ≥ 5 mg/l. Subjects with elevated CRP levels at more than 80% of visits were defined as inflammatory SSc. The longitudinal CRP profiles were correlated with disease characteristics and comorbidities. Results: A total of 1815 consecutive visits of 131 SSc patients were analyzed. Over the observed time span (7.6 (1.0-19.5) years), 18.3% (n = 24) of patients had continuously elevated CRP levels (inflammatory SSc), whereas in 29% (n = 38), CRP levels were always in the normal range. There was no association between disease duration and CRP levels at first visit. Inflammatory SSc was associated with male gender (p = 0.022), anti-Scl-70 antibodies (p = 0.009), diffuse cutaneous SSc (p = 0.036), pulmonary fibrosis (p < 0.001), rheumatoid arthritis (p = 0.007), and cardiac arrhythmia (p = 0.048). Moreover, patients with inflammatory SSc revealed higher modified Rodnan skin scores (p < 0.001); lower forced vital capacity (FVC) (p < 0.001), total lung capacity (p = 0.001), and diffusing capacity (p = 0.008); and faster decline of FVC per year (p = 0.007). Even treatment with cyclophosphamide (CYC) did not decrease CRP levels (p = 0.754). Conclusion: Inflammatory SSc is characterized by a more severe phenotype, high morbidity, and a large proportion of male patients. Even treatment with CYC does not alter CRP levels in this subpopulation with a high unmet medical need.

BackgroundElevated levels of C-reactive protein (CRP) in systemic sclerosis (SSc) have been linked to early inflammatory stages of the disease.ObjectivesThis study has been set to investigate CRP levels in a longitudinal cohort of SSc patients and to correlate these findings to comorbidities and disease characteristics.MethodsIn this retrospective study patients with SSc were recruited from the outpatient clinic of the Department of Rheumatology and Clinical Immunology, University Medical Centre Freiburg. Only patients with at least three consecutive visits at our centre over at least one year were included in this study. CRP serum levels were measured at every visit and categorised as positive if CRP concentrations were ≥5 mg/L. Subjects with elevated CRP levels at more than 80% of visits were defined as being persistently positive. The longitudinal CRP profile was correlated to comorbidities and disease characteristics.ResultsA total of 1852 consecutive visits of 131 SSc patients were analysed. Over the observed time span (91136–56 months) 19% (n=25) of patients had continuously elevated CRP levels, whereas in 29% (n=38) CRP levels were always in the normal range. There was no association between disease duration and CRP levels at first visit (p>0.5). Persistent CRP elevation was associated (p<0.05) with anti-topoisomerase I-antibodies, diffuse cutaneous SSc (dcSSC), modified Rodnan skin score (mRSS), pulmonary fibrosis, and cardiac arrhythmia, whereas no associations with arthritis or malignancy were found (p>0.1). In a patient with dcSSc and persistent elevated CRP even cyclophosphamide and autologous stem cell transplantation did not alter CRP levels.ConclusionsPersistently elevated CRP levels characterise a more severe fibrotic phenotype and a higher prevalence of cardiac arrhythmias.Disclosure of InterestNone declared