Supplementary Material for: Superior Mesenteric Artery Syndrome Improved by Enteral Nutritional Therapy: A Retrospective Case-Series Study in a Single Institution

<b><i>Introduction:</i></b> Superior mesenteric artery syndrome (SMAS) is a relatively rare cause of chronic duodenal obstruction, owing to the compression of the third portion of the duodenum. <b><i>Objectives:</i></b> This retrospective study aims to discuss the efficacy of enteral nutrition (EN) therapy in nutritional status and symptom improvement at a short-term follow-up for SMAS patients. <b><i>Methods:</i></b> We retrospectively analyzed clinical data of patients diagnosed as SMAS and treated with EN from September 2012 to January 2019. <b><i>Results:</i></b> Twenty-six patients were included (16 women; mean age 24.96 ± 11.77 years), none was excluded, and one was lost to follow-up. The patients’ mean body weight was 40.94 ± 10.16 kg, mean weight loss 11.73 ± 7.58 kg, and mean body mass index (BMI) 14.82 ± 2.52 kg/m². The mean duration of EN therapy was 10.10 ± 4.66 months. Serum level of nutritional indicators, BMI and body weight increased after EN therapy. During a median follow-up of 24 months (9–44) after EN therapy, the mean symptom score decreased from 24.28 ± 9.57 to 8.06 ± 8.29 (<i>p</i> &lt; 0.0001), and 65% of patients’ symptoms resolved and 15% of patients’ symptoms improved. In total, 16 complications occurred, including tube blockage, peristomal wound infections, peristomal leakage, granulomas, and nasopharyngeal pain. <b><i>Conclusion:</i></b> EN therapy may be an effective option for SMAS patients. While it might not remove all symptoms, it can improve the nutritional status to support subsequent treatments.