Early progression of systemic sclerosis: a longitudinal cohort study on disease evolution and microvascular changes

This study aimed to evaluate the time from early-stage systemic sclerosis (SSc), to the onset of significant disease progression. A secondary objective was to identify early clinical features most strongly associated with disease progression. Additionally, the study examined the course of microvascular changes over time.

In this prospective longitudinal cohort study (Hit Hard and Early trial, 3 years open label follow-up), we included patients who met the adjusted Very Early Diagnosis of Systemic Sclerosis criteria, with puffy fingers for less than 3 years. Disease progression was defined as skin or organ involvement. Microvascular changes were tracked through serial nailfold videocapillaroscopy, and Kaplan-Meier estimates were used to analyse time to disease progression. Baseline predictors of progression were explored with univariate logistic regression.

Thirty patients were included, 70% female, with a median duration of puffy fingers of 5.5 months. Anticentromere antibodies were present in 73%, and 75% showed an active nailfold capillaroscopy pattern at baseline. Over 3 years, 43% (95% CI: 25.6%-61.2%) developed clinically significant disease progression, predominantly manifesting as pitting scars, digital ulcers, and/or skin thickening. Mean capillary density declined over time, and 55% of patients with an early SSc capillaroscopy pattern progressed to an active or late pattern within 24 months.

A large proportion of patients showed clinically relevant disease progression within 3 years. In spite of the limited sample size, the strong association between anti-ribonucleoprotein (anti-RNP) antibodies and disease progression underlines the prognostic value of this biomarker. Frequent and standardised nailfold capillaroscopy imaging provided insights into microvascular changes.