Prevalence, distribution and associations of the scleroderma capillaroscopic patterns: new insights from the Italian SPRING-SIR registry.

Abstract

To assess the relationship between disease duration and the prevalence/distribution of nailfold videocapillaroscopy (NVC) patterns, named according to the current classification as 'early', 'active' and 'late', in a large cohort of systemic sclerosis (SSc) patients. A cross-sectional analysis was conducted on 1689 patients undergoing standardized NVC. Clinical-serological data and treatments were collected. Statistical comparisons and multivariable logistic regression models were applied, including analyses based on disease duration. The prevalence of NVC patterns was as follows: 'early' 21.6%, 'active' 47.4%, 'late' 25.7% and normal/non-specific 5.3%. The distribution by disease duration showed that the three main patterns were always present. While the 'early' and 'active' progressively decreased (from 30.3% and 51.9% in patients with ≤5 yrs, to 14.6% and 43.5% in those >10 yrs, P < 0.01), the 'late' pattern increased from 13.2% (≤5 yrs) to 36.0% (>10 yrs) (P < 0.001) and was associated with internal organ involvement, anti-topoisomerase antibodies and more therapies (P < 0.01). Conversely, the 'early' and 'active' patterns were associated with the limited-cutaneous subset (P < 0.01) and anti-centromere antibodies (P < 0.001). Multivariable analysis confirmed a strong association between the 'late' pattern and skin/peripheral vascular involvement. Notably, the presence of the 'late' pattern in patients with ≤2 yrs (10.9%) was significantly associated with scleroderma renal crisis (P = 0.012). SSc-NVC patterns are not strictly time-dependent and can be observed at any stage of the disease, suggesting that microvascular damage progression is heterogeneous across different disease periods. Therefore, a revised classification of NVC changes considering both disease duration and NVC severity could improve its prognostic accuracy.