Background: Eating disorders (ED) are often diagnosed at an advanced stage because traditional symptoms related to unhealthy eating habits are poorly recognized. ED may be also associated with non-traditional and objective biomarkers, which could prove an important screening tool to support health care professionals in diagnosing, treating, and ultimately preventing ED. Aim: To investigate the association between non-traditional physiological ED biomarkers and symptoms of ED among female college students. Methods: This study included 113 female college students, aged 18 to 23 years, enrolled in their first semester as a Bachelor of Health Sciences undergrad at public universities in the urban zone of Recife, Brazil. Symptoms of ED were measured by self-report questionnaires. Circulating levels of IL-6, IL-10, leptin, insulin, ghrelin, PYY and adiponectin were assessed using commercial immunoassays. Results: Students with symptoms of an ED exhibited higher values of IL-6 (p = 0.03) and leptin (p < 0.001) compared to those without symptoms. A positive correlation was found between leptin levels and bulimia nervosa (r = 0.42; p = 0.00), between leptin levels and binge eating (r = 0.38; p = 0.00), and between IL-6 concentrations and binge eating (r = 0.25; p = 0.04). Multiple linear regression analysis with anorexia nervosa, bulimia nervosa and binge eating as dependent variables showed that IL-6 and leptin best explained ED symptoms, even when adjusted for body mass index (BMI). Conclusions: These findings suggest that peripheral peptides, namely leptin and IL-6, are associated with symptoms of ED in female college students. Future studies are needed to determine if there is a causal relationship between these biomarkers and the onset of ED. Relevance for patients: If future longitudinal studies demonstrate causality between the biomarkers assessed here and ED symptoms, these serum makers could be used as screening tool for inappropriate eating behavior. This may in turn improve the early diagnosis, treatment, and, ultimately, the prognosis of patients with ED.
Keywords: anorexia nervosa; bulimia nervosa; eating disorders; interleukin-6; leptin; peptides; students.