Optimizing Malnutrition Risk Detection in Inflammatory Bowel Disease: A Longitudinal Analysis of Serial Nutritional Screening Tools

Background: Malnutrition is frequently under-investigated during remission in patients with Inflammatory Bowel Disease (IBD), despite its significant impact on clinical outcomes and quality of life. This study aimed to evaluate the increase in diagnostic performance of five nutritional screening tools (NSTs) when serially administered to IBD outpatients in sustained clinical remission. Methods: In this prospective, single-center cohort study, NSTs were administered, and body composition analysis was performed in IBD patients at baseline and after six months. At both time points, the sensitivity, specificity, predictive values, and accuracy of NSTs in detecting malnutrition and persistent malnutrition per ESPEN and GLIM criteria were evaluated, comparing repeated to single-point assessments. A sensitivity analysis using low FFMI as a reference was also performed. Results: Sixty-six IBD patients (32 Crohn’s disease; 34 ulcerative colitis) were enrolled. At baseline, 25.7% and 9% of patients were malnourished according to ESPEN and GLIM criteria, respectively, with 7.5% exhibiting low FFMI. Malnutrition prevalence increased over time to 53%, 16.6%, and 16.6%, respectively. Among NSTs, MUST and SaskIBD-NR consistently exhibited the highest specificity for malnutrition detection at baseline, at 6 months, and for persistent malnutrition for ESPEN, GLIM and low FFMI. Serial (repeated) NST administration markedly improved the specificity of all tools, compared to single-point assessments. Conclusions: Serial nutritional screening with MUST or SaskIBD-NR significantly enhances the specificity of malnutrition risk detection in IBD patients in remission, supporting the incorporation of repeated nutritional assessments into clinical practice to offer a practical strategy to enhance screening effectiveness in IBD outpatient care.