Inflammatory profiles in women with eating disorder: Linking inflammatory biomarkers to clinical phenotypes.

INTRODUCTION: Eating disorders (ED) represent a group of very complex and serious diagnoses characterized by emotional dysregulation and impulsivity. New approaches are necessary to achieve effective diagnosis and treatments. Shifting biomarker research away from the constraints of diagnostic categories may effectively contribute to a dimensional differentiation across disorders according to neurobiology (e.g., inflammatory biomarkers). Thus, the aim of our study was to identify inflammatory profiles in patients with ED.

METHODS: A sample of 100 women with an ED (23.4 ± 8.55 years) and 59 healthy controls (HC) (20.22 ± 4.18 years) was used. K-means cluster analysis was followed to identify inflammatory clusters considering seven blood biomarkers (iNOS, TNFα, COX2, p38, ERK, TBARS and PPARγ). Moreover, a wide assessment of clinical features was conducted.

RESULTS: Two distinct clusters were identified. Cluster 1 patients were characterized by higher inflammatory levels of TNF-α, COX2, p38, and ERK, and had more restrictive anorexia diagnosis than cluster 2. Cluster 2 participants showed higher inflammatory levels of iNOS and were older than cluster 1 and controls and had lower BMI than HC. In addition, they had higher levels of bulimic symptoms than those from the cluster 1 and HC, and higher impulsivity than HC. All ED patients (regardless of cluster) showed higher ED symptoms and more trauma than HC.

CONCLUSIONS: Our study revealed that inflammatory dysfunction may be linked with clinical endophenotypes in ED, one more restrictive (cluster 1) with an inflammation/oxidative endophenotype more cytokine and MAPK/ERK mediated, and the other more impulsive, with more bulimic symptoms (cluster 2) with NO free radical high output source iNOS. Trauma seems to be a vulnerability factor for both endophenotypes.