Nailfold videocapillaroscopy patterns associate with interstitial lung disease and skin fibrosis in systemic sclerosis patients.

BackgroundCapillaroscopic patterns in systemic sclerosis (SSc) are routinely assessed by nailfold videocapillaroscopy (NVC), yet their broader clinical relevance remains incompletely defined.MethodsIn a prospective cross-sectional study of 70 SSc patients, we evaluated associations between NVC patterns and key clinical domains: interstitial lung disease (ILD), skin fibrosis (the modified Rodnan Skin Score, mRSS), SSc-specific autoantibody profile including anti-Th/To, immunosuppressive treatments, and patient-reported outcome measures (PROMs): SSc Quality of Life scale (SScQoL), Health Assessment Questionnaire-Disability Index (HAQ-DI), and Visual Analog Scales (VAS) for pain and disease activity (PtGA). Statistical methods included Spearman correlation, Mann–Whitney U-test, receiver operating characteristic (ROC) analysis, and logistic regression. p-values were adjusted using the false discovery rate (FDR).ResultsAdvanced NVC patterns (4–5) were significantly associated with ILD (OR = 3.73, 95% CI: 1.42–9.81, q = 0.0058), and this association remained consistent across multiple multivariable and parsimonious logistic regression models adjusting for anti-Scl-70 status, disease duration, or skin fibrosis (mRSS), with effect estimates around fourfold increased odds of ILD. ROC analysis demonstrated diagnostic discrimination for ILD based on NVC pattern (AUC = 0.688). Higher NVC severity was also associated with greater skin fibrosis (ρ = +0.38, q = 0.0283), with progressive increases in median mRSS from NVC pattern 2 to 5 (4.0 → 11.0). Strong associations were found with PROMs: worse SScQoL (q = 0.0040), higher HAQ-DI (q = 0.0027), and elevated PtGA (q = 0.0040). A novel inverse correlation was identified between NVC patterns and anti-Th/To antibody positivity (q = 0.022). Exposure to cyclophosphamide (CYC) or mycophenolate mofetil (MMF) was associated with more severe capillaroscopic damage (both q = 0.019) most likely reflecting greater disease severity rather than a treatment effect.ConclusionOur study demonstrates significant associations between NVC severity and selected clinical, serological, therapeutic, and patient-reported domains in SSc.