Gastrointestinal disorders in systemic sclerosis: cluster analysis and prognosis from a French prospective cohort

Objective The gastrointestinal tract (GIT) is frequently involved in systemic sclerosis (SSc) and is responsible for alteration of quality of life. Many complications can occur, including chronic intestinal pseudo-obstruction, digestive haemorrhage and small-intestinal bacterial overgrowth. Since early development of organ failure is associated with poor prognosis, we need to identify risk factors associated with severe GIT involvement to prevent severe forms of the disease. Methods We conducted an observational prospective study, which included 90 SSc patients from December 2019 to September 2021. We collected questionnaires about digestive manifestations and quality of life, blood and stool samples, and performed imaging. At inclusion and throughout the study we assessed the occurrence of malnutrition and severe GIT disorders. We performed statistical analysis to highlight eventual risk factors associated with digestive manifestations, including hierarchical cluster analysis. Results A majority of our patients had gastro-oesophageal manifestations (93.3%), followed by intestinal manifestations (67.8%) and anorectal manifestations (18.9%). We found a correlation between anorectal disorders and cardiac disease, and between gastro-oesophageal involvement and impaired pulmonary function tests. Smoking was significantly associated with occurrence of severe GIT disorders. Malnutrition was frequent and associated with more cardiac and pulmonary disease. Cluster analysis identified three groups of patients, including one cluster with cardiac and digestive involvement. Conclusion GIT manifestations are frequent and severe in SSc. Smoking appears to be associated with severe disease. Anorectal manifestations may be associated with cardiac disease, but we need more studies to validate these results.