Monitoring Neutrophil-to-Lymphocyte Ratio Dynamics for Personalized Treatment in Adolescent Eating Disorders: A retrospective cohort study

Objective This study aimed to evaluate the dynamics of the neutrophil-to-lymphocyte ratio (NLR) during the initial hospitalization of patients with eating disorders (EDs) and to assess its potential as a biomarker for monitoring disease severity and treatment response. Methods A retrospective chart review was conducted with 55 patients aged ≤ 16 years diagnosed with anorexia nervosa or avoidant/restrictive food intake disorder and admitted to Jichi Medical University Hospital between 2015 and 2021. Sociodemographic and clinical characteristics including sex, age, rate of weight gain, percentage of ideal body weight (%IBW), tube feeding treatment, and NLR were obtained. Statistical analyses used a mixed model for repeated measures to assess NLR changes regarding %IBW and other clinical factors. Results The NLR at admission was lower in the malnourished state but increased with weight recovery. MMRM revealed that tube feeding treatment and restoration of %IBW significantly predicted an increase in the NLR. The interaction between tube feeding and the quadratic term of %IBW was also significant, indicating distinct patterns of NLR changes: without tube feeding, NLR increased linearly with weight recovery, whereas with tube feeding, NLR exhibited a non-linear, upward-convex parabolic trend. Discussion These findings indicate that NLR may serve as a potential biomarker for monitoring recovery in patients with EDs, reflecting nutritional status and tube feeding-related factors. NLR measurement could be a practical tool for tailoring treatment strategies. Further research is warranted to explore NLR's utility across diverse ED populations and assess its responsiveness to various interventions, advancing personalized medicine in this field.