This Evidence Note interprets collagen turnover biomarkers in systemic sclerosis as phase-dependent signals of active extracellular matrix remodeling rather than simple static measures of fibrotic burden. Building on recent discussion in The Journal of Rheumatology, the note argues that inconsistent biomarker performance may reflect disease phase, organ-specific timing, immune–fibrotic coupling, and competing tissue trajectories rather than biomarker failure alone. Within the Universal Resonance Model (URM), fibrosis is framed as a dynamic process involving formation, degradation, remodeling, and system-level instability. The work highlights why stable circulating biomarker levels may still hide divergent local processes across skin, lung, and other tissues. The note is relevant to systemic sclerosis, fibrotic disease, collagen neoepitopes, biomarker interpretation, clinical trial design, and dynamic systems approaches to chronic disease.
Anita Domargård (Tue,) studied this question.