Significant nailfold capillary loss and late capillaroscopic pattern are associated with pulmonary arterial hypertension in systemic sclerosis.

OBJECTIVE

To evaluate differences in nailfold videocapillaroscopy (NVC) findings between SSc patients with and without a diagnosis of pulmonary arterial hypertension (PAH).

METHODS

One hundred and ten SSc patients were enrolled in this cross-sectional, case-control, multicentre study. Patients were divided into cases (SSc-PAH confirmed by right heart catheterization) and controls (SSc-nonPAH with low probability of PAH). NVC patterns (early, active and late) and morphological parameters (microvascular density, non-specific abnormalities, giant capillaries, micro-haemorrhages, avascular areas) were considered using a semiquantitative scoring system.

RESULTS

SSc-PAH patients showed higher frequencies of late pattern (P < 0.01), non-specific abnormalities (P < 0.01), lower capillary density (P < 0.01), higher avascular areas (P < 0.01) and a higher mean NVC score (P < 0.01). Contrarily, the early/active pattern (P < 0.01) and a higher rate of micro-haemorrhages (P = 0.04) were more frequent in non-PAH patients. By a multivariate analysis, SSc-PAH patients, compared with non-PAH, had more non-specific abnormalities [27/55, 49.1% vs 10/55, 18.2%; adjusted odd ratio (OR) 16.89; 95% CI: 3.06, 93.16], a lower capillary density (grade 3, 20/55, 36.4% vs 5/55, 9.1%; adjusted OR 38.33; 95% CI: 2.34, 367.80) and avascular areas (18/55, 32.7% vs 10/55, 18.2%; adjusted OR 16.90; 95% CI: 2.64, 44.35). A correlation was found between the mean pulmonary arterial pressure and avascular areas (P < 0.01), capillary density (P < 0.01) and non-specific abnormalities (P < 0.01). A clinical model including the NVC variables may be able to predict a diagnosis of PAH.

CONCLUSION

Our results indicate that the distinctive peripheral microcirculatory injury of SSc, i.e. capillary loss and morphological abnormalities, appear more severe and pronounced in patients with SSc-PAH.