The Role of Duration of Untreated Illness (DUI) on the Course and Biochemical Parameters of Female Patients Affected by Anorexia Nervosa

Abstract

Objective: Anorexia nervosa (AN) presents the highest rate of mortality among psychiatric disorders, making an early diagnosis and proper management essential. The purpose of the study was to investigate the role of duration of untreated illness (DUI) on the course and biochemical parameters in a sample of 76 female patients with AN.

Method: Correlation analyses and one-way analyses of variance were performed to analyze the relation between DUI and quantitative and qualitative variables, respectively. Statistically significant factors from correlation analyses were inserted in a linear regression model as independent variables with the DUI as the dependent variable.

Results: A longer DUI was directly correlated with age (r = 0.35, p < 0.01), duration of illness (r = 0.61, p < 0.01), potassium (K) plasma levels (r = 0.47, p = 0.02), and platelet/lymphocyte ratio (PLR) (r = 0.25, p = 0.04). A longer DUI was inversely correlated with the sodium/potassium ratio (Na/K) (r = -0.42, p = 0.047). Linear regression analysis confirmed the direct association between a longer DUI with age (B = 0.12, p = 0.01) and K levels (B = 3.18, p = 0.017).

Discussion: The higher K plasma levels in patients with longer DUI may indicate an abuse of supplements and/or an alteration of the hypothalamus-pituitary-axis (HPA) or renin-angiotensin systems. In support of this hypothesis, alterations in PLR were identified in subjects with abnormal bone mineral density. Further research is needed to confirm the present findings.

Keywords: anorexia nervosa; biochemical parameters; clinical variables; duration of untreated illness (DUI).