AbstractsBiology & Animal Science

Inflammation, metabolic syndrome, & early life stress in major depression

by Sara Zeugmann

Institution: Freie Universität Berlin
Degree: PhD
Year: 2015
Record ID: 1118616
Full text PDF: http://edocs.fu-berlin.de/diss/receive/FUDISS_thesis_000000099162


Background: Research increasingly considers the immunological effects of major depression. The impact of the metabolic syndrome on inflammatory biomarkers is investigated in the first study. The second study assesses the impact of early life stress on inflammatory biomarkers in adulthood. The third study combines the results of the first two by determining the relationship between components of the metabolic syndrome, early life stress, and fibrinogen levels. Methods: 70 depressed inpatients with or without the metabolic syndrome were assessed at admission to the clinic and after amelioration of depressive symptomatology for study 1. 25 of these provided data for studies 2 and 3. The metabolic syndrome was diagnosed via the International Diabetes Federation’s criteria. Severity of depression was measured with the 17-item Hamilton Depression Rating Scale (HDRS). Early life stress and parental bonding were quantified with the Childhood Trauma Questionnaire (CTQ), and Parental Bonding Inventory (PBI). Biomarkers included adiponectin, resistin, serum amyloid A (SAA), C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), soluble E-selectin (sE-selectin), interleukin-6 (IL-6), and CD40 ligand (CD40L) (the last two only in the first study). The relationships between the metabolic syndrome, early life stress, and fibrinogen were calculated with path analyses. Two main models were tested: the metabolic syndrome mediating/ not mediating between early life stress and fibrinogen levels. Results: Study 1: A 2-factorial ANOVA (metabolic syndrome x time) revealed that the metabolic syndrome’s presence affected adiponectin (F43,1= 5.56; p< .05; η2= .11) and IL-6 levels (F25,1= 6.80; p< .05; η2= .21) significantly. There was also a trend for effects on fibrinogen levels (F47,1= 3.66; p= .06; η2= .08). Study 2: Nearly all patients reported a parental style of “affectionless control”. Physical neglect significantly predicted fibrinogen levels (R2= .42, adjusted R2= .27, ß= .56, p= .04). Study 3: The model without the mediating effect of the metabolic syndrome provided an excellent fit for our data: (χ2= 0.02, df= 1, p= .90, CFI= 1.00, NNFI= 2.71, RMSEA= 0.00). Conclusion: For the first time, an additive effect of the metabolic syndrome on inflammatory biomarkers was demonstrated in depressed patients. Furthermore, inflammation might be an important mechanism mediating the unfavorable effects of adverse childhood experiences. The metabolic syndrome was not found to be a mediator between early life stress and fibrinogen levels in adulthood. Therapeutic options targeting the mood-inflammatory pathway in depression, such as psychotherapeutic treatment of early childhood adversities or novel psychopharmacologic interventions will be discussed. Hintergrund: Eine zunehmende Anzahl von Untersuchungen beschäftigt sich mit immunologischen Aspekten der Major Depression. Eingangs wird der Einfluss des metabolischen Syndroms auf Konzentrationen immunologischer Biomarker untersucht. Die zweite Studie beschäftigt sich mit dem Einfluss…