Radwan, Yasser A

Objectives: To study the incidence, risk factors, and outcomes of conduction and rhythm disorders in a population-based cohort of patients with systemic sclerosis versus nonsystemic sclerosis comparators. Methods: An incident cohort of patients with systemic sclerosis (1980–2016) from Olmsted County, MN, was compared to age- and sex-matched nonsystemic sclerosis subjects (1:2). Electrocardiograms, Holter electrocardiograms, and a need for cardiac interventions were reviewed to determine the occurrence of any conduction or rhythm abnormalities. Results: Seventy-eight incident systemic sclerosis cases and 156 comparators were identified (mean age 56 years, 91% female). The prevalence of any conduction disorder before systemic sclerosis diagnosis compared to nonsystemic sclerosis subjects was 15% versus 7% ( p = 0.06), and any rhythm disorder was 18% versus 13% ( p = 0.33). During a median follow-up of 10.5 years in patients with systemic sclerosis and 13.0 years in nonsystemic sclerosis comparators, conduction disorders developed in 25 patients with systemic sclerosis with cumulative incidence of 20.5% (95% confidence interval: 12.4%–34.1%) versus 28 nonsystemic sclerosis patients with cumulative incidence of 10.4% (95% confidence interval: 6.2%–17.4%) (hazard ratio: 2.57; 95% confidence interval: 1.48–4.45), while rhythm disorders developed in 27 patients with systemic sclerosis with cumulative incidence of 27.3% (95% confidence interval: 17.9%–41.6%) versus 43 nonsystemic sclerosis patients with cumulative incidence of 18.0% (95% confidence interval: 12.3%–26.4%) (hazard ratio: 1.62; 95% confidence interval: 1.00–2.64). Age, pulmonary hypertension, and smoking were identified as risk factors. Conclusion: Patients with systemic sclerosis have an increased risk of conduction and rhythm disorders both at disease onset and over time, compared to nonsystemic sclerosis patients. These findings warrant increased vigilance and screening for electrocardiogram abnormalities in systemic sclerosis patients with pulmonary hypertension.

Systemic sclerosis (SSc) is characterised by non-inflammatory vasculopathy, autoimmunity and widespread fibrosis. While the presence of antineutrophil cytoplasmic antibodies (ANCAs) has been reported in SSc, their association with ANCA-associated vasculitis is exceedingly rare. Myeloperoxidase ANCA is more common than proteinase-3 ANCA, and glomerulonephritis is the most common clinical presentation of ANCA-associated vasculitis in SSc. ANCAs have been associated with the adverse disease outcomes in SSc, including higher mortality per recent reports. A 65-year-old man with diffuse cutaneous SSc for 6 years presented with new-onset peripheral neuropathy. Workup revealed a positive proteinase-3 and cytoplasmic ANCA, and histopathology confirmed an inflammatory vasculitic neuropathy. The patient was successfully treated with rituximab. Our case highlights the importance of checking ANCA in SSc at baseline, given the risk of disease-related complications, even years later. Tissue biopsy is often warranted for confirmation of vasculitis and prompt treatment can optimise long-term outcomes.