Objective
The aim of this study was to evaluate the association of nailfold videocapillaroscopy (NVC) changes and the presence and severity of interstitial lung disease (ILD) in systemic sclerosis.
Methods
This was a cross-sectional analysis of 48 systemic sclerosis patients (21 patients with ILD). The NVC characteristics considered were capillary organization, capillary loss (CL), avascular areas, enlarged and giant capillaries, hemorrhages, abnormally shaped capillaries, edema, and intermittent flux.
We analyzed the association between NVC findings and (1) presence and extension of ILD and (2) percent predicted of forced vital capacity (FVC) and the carbon monoxide diffusing capacity (DLCO).
Results
Capillary loss and avascular areas showed a significant association with the presence of ILD (odds ratio, 18.57; 95% confidence interval [CI], 2.17–158.72 [p = 0.008]; and odds ratio, 4.64; 95% CI, 1.35–15.91 [p = 0.015], respectively). Receiver operating characteristic (ROC) curve analysis confirmed the association between CL and ILD (area under the ROC curve, 90.1%; 95% CI, 81.8–91.4). Avascular areas and CL were associated with a worse pulmonary function (FVC −18.1% [p = 0.034], DLCO −14.0% [p = 0.013]; and FVC −15.3% [p = 0.086], DLCO −12.3% [p = 0.049], respectively). No association was found between other NVC findings and ILD or lung function.
Conclusions
Capillary loss and avascular area showed a significant association with the presence of ILD, supported by ROC curve analysis. These results may reinforce a prognostic role for NVC and a physiopathology mechanism for ILD based on vascular damage.
