Factors associated with variations in the 6-minute walk distance during the follow-up of patients with systemic sclerosis

INTRODUCTION: The 6-minute walk distance (6MWD) is commonly used to assess functional capacity in patients with systemic sclerosis (SSc), but its ability to reflect changes in cardiopulmonary status during follow-up remains uncertain. This study aimed to investigate whether variations in the 6MWD accurately mirror changes in organ involvement over time in SSc patients. METHODS: We conducted a longitudinal study on a global cohort of 227 consecutive SSc patients, including a subgroup of 88 patients with ILD or PH, over a two-year follow-up period. Statistical analyses were performed to assess associations between variations (Δ) of 6MWD (Δ6MWD) and evolution of organ involvement. RESULTS: = 0.36 in multivariate analysis), suggesting the influence of additional factors to explain the majority of Δ6MWD. CONCLUSION: While it remains valuable as a marker of disability and functioning, the variation in the 6MWD does not seem to be a robust surrogate for modifications in organ involvements of SSc patients.