Hostility and helper T-cells in patients with bulimia nervosa

OBJECTIVE

The study aimed to analyze the correlation between lymphocyte counts and several psychopathological variables associated with psychological instability (depression, hostility, impulsivity, self-defeating personality traits, and borderline personality symptoms) in patients with bulimia nervosa (BN).

METHOD

Sixty BN patients were assessed, using specific scales for eating pathology, general psychopathology, impulsivity, depression, and borderline personality features. Lymphocyte and lymphocyte subset counts were performed. Plasma cortisol at 8:00, before and after administration of 1 mg of dexamethasone at 23:00, was determined. The influence of body weight, and the use of tobacco, alcohol, and caffeine was controlled. The relationship between each isolated variable and the number of immune cells was analyzed. In a second step, supplementary post-hoc analysis of the variables was introduced to confirm the accuracy of the psychopathological assessment.

RESULTS

Hostility was negatively correlated with the number of helper T-cells (CD4+). Patients with high hostility had lower CD4+ cell counts and lower CD4+/CD8+ ratios. In the post-hoc control study, hostility was significantly related with other "interpersonal" items.

CONCLUSIONS

These results support the idea that hostility, as an expression of disturbed interpersonal relationships, could play a role as a modulator of immune activity in patients with BN.

Relationship between plasma concentrations of cytokines, ratio of CD4 and CD8, lymphocyte proliferative responses, and depressive and anxiety state in bulimia nervosa

OBJECTIVE

Immunological dysfunction in participants with bulimia nervosa (BN) might be due to not only chaotic eating behavior but also psychological state, such as depression and anxiety, because studies have found a close relationship between depression, anxiety, and immunological dysfunction.

METHOD

Participants included 20 females with BN and 14 control females. In eight BN participants, immune function was measured twice, before and after inpatient treatment. Cytokines [interleukin (IL)-1 receptor antagonist, IL-2 soluble receptor alpha, IL-6 soluble receptor (sIL-6r), and tumor necrosis factor soluble receptor II (sTNF-rII)], lymphocyte subsets (CD4 and CD8), and lymphocyte proliferative responses were measured.

RESULTS

There were no differences in plasma cytokine levels or lymphocyte subsets between the BN participants and the controls. Conversely, lymphocyte proliferative responses were significantly lower in BN participants than in the controls. Lymphocyte proliferative responses negatively correlated with anxiety trait and improved with an improvement of bulimic state.

CONCLUSION

The comorbid nonspecific anxiety trait significantly contributes to suppressing lymphocyte proliferative responses in BN participants.

Autoantibodies against neuropeptides are associated with psychological traits in eating disorders

Previously, we identified that a majority of patients with anorexia nervosa (AN) and bulimia nervosa (BN) as well as some control subjects display autoantibodies (autoAbs) reacting with alpha-melanocyte-stimulating hormone (alpha-MSH) or adrenocorticotropic hormone, melanocortin peptides involved in appetite control and the stress response. In this work, we studied the relevance of such autoAbs to AN and BN. In addition to previously identified neuropeptide autoAbs, the current study revealed the presence of autoAbs reacting with oxytocin (OT) or vasopressin (VP) in both patients and controls. Analysis of serum levels of identified autoAbs showed an increase of IgM autoAbs against alpha-MSH, OT, and VP as well as of IgG autoAbs against VP in AN patients when compared with BN patients and controls. Further, we investigated whether levels of these autoAbs correlated with psychological traits characteristic for eating disorders. We found significantly altered correlations between alpha-MSH autoAb levels and the total Eating Disorder Inventory-2 score, as well as most of its subscale dimensions in AN and BN patients vs. controls. Remarkably, these correlations were opposite in AN vs. BN patients. In contrast, levels of autoAbs reacting with adrenocorticotropic hormone, OT, or VP had only few altered correlations with the Eating Disorder Inventory-2 subscale dimensions in AN and BN patients. Thus, our data reveal that core psychobehavioral abnormalities characteristic for eating disorders correlate with the levels of autoAbs against alpha-MSH, suggesting that AN and BN may be associated with autoAb-mediated dysfunctions of primarily the melanocortin system.