The relationship between body mass index and mental state in patients with anorexia nervosa during inpatient treatment

Background: eating disorders (EDs), particularly anorexia nervosa, are frequently accompanied by pronounced depressive, anxiety, and obsessive-compulsive symptoms, which significantly complicate the course of the disease and necessitate a comprehensive therapeutic approach. Investigating the relationship between the degree of physical depletion and the psycho-emotional state of patients enables the optimization of treatment strategies and improves intervention effectiveness. Objective. To assess the association between the degree of physical depletion and the severity of depressive, anxiety, and obsessive-compulsive symptoms in female patients with anorexia nervosa undergoing inpatient treatment, as well as to identify patterns of response to therapy. Materials and Methods. The study included 40 female patients with anorexia nervosa receiving inpatient care. All participants underwent standard nutritional support, pharmacotherapy according to a unified protocol, and psychotherapy. The psycho-emotional state was assessed using the PHQ-9, GAD-7, and Yale-Brown Obsessive Compulsive Scale during the beginning of inpatient period and one month after. Data analysis included descriptive statistics, Pearson correlation analysis, and cluster analysis using the K-means method. Results. Most patients presented with severe depressive (92.3 %), anxiety (79.5 %), and obsessive-compulsive (82.5 %) symptoms at admission. After one month of inpatient treatment, there was a significant increase in BMI and a reduction in psychopathological symptoms. Correlation analysis revealed a statistically significant negative relationship between BMI and anxiety levels, while correlations with depression and OCD symptoms were not significant. Cluster analysis identified three patterns of treatment response: comprehensive improvement, mixed response, and intensive physical recovery. Conclusions. The findings confirm the wide range of symptoms in anorexia nervosa and reveal a specific association between the degree of emaciation and anxiety symptoms. The existence of different patterns of treatment response substantiates the need for a personalized and multidisciplinary approach to managing this patient population.