The acute‐phase mediator serum amyloid A is associated with symptoms of depression and fatigue

• Published in: Acta psychiatrica Scandinavica Vol. 135; no. 5; pp. 409 - 418
• Main Authors: Bryleva, E. Y., Keaton, S. A., Grit, J., Madaj, Z., Sauro‐Nagendra, A., Smart, L., Halstead, S., Achtyes, E., Brundin, L.
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.05.2017
• Subjects: Adult; Aged; biomarker; Biomarkers; C-Reactive Protein - metabolism; Cross-Sectional Studies; C‐reactive protein; Depression - metabolism; Fatigue; Fatigue - metabolism; Female; Humans; inflammation; Interleukin-6 - blood; interleukin‐6; Male; Mental depression; Middle Aged; mood disorders; Psychiatric Status Rating Scales; Psychopathology; Serum Amyloid A Protein - metabolism; Tumor Necrosis Factor-alpha - blood; Tumor necrosis factor-TNF; Young Adult; C-reactive protein; biomarker; inflammation; mood disorders; interleukin-6
• ISSN: 0001-690X; 1600-0447
• DOI: 10.1111/acps.12730

Objective Establish whether inflammatory biomarkers—serum amyloid A (SAA), C‐reactive protein (CRP), interleukin‐6 (IL‐6), and tumor necrosis factor‐α (TNF‐α)—are related to key symptoms of depression, including anxiety and fatigue, in a cross‐sectional, out‐patient setting to identify biomarkers that reflect psychiatric symptomatology in a naturalistic, real‐life population. Methods We measured SAA, CRP, IL‐6, and TNF‐α in plasma samples from 89 adult psychiatric out‐patients by multiplex, high‐sensitivity electrochemiluminescent assays. Psychiatric symptoms were evaluated using the Hamilton Depression Rating Scale (HAMD‐17), the Patient Health Questionnaire (PHQ‐9), and the Center for Epidemiological Studies Depression Scale (CES‐D). Results Plasma SAA was most robustly associated with depressive symptoms across diagnostic boundaries in this cohort of out‐patients. Elevated SAA was significantly associated with higher total scores on the HAMD‐17 scale and correlated with multiple scale items that rated symptoms of fatigue and depressed mood, but not with anxiety‐related items. Conclusions SAA might constitute a cross‐diagnostic marker indicative of depressed mood and fatigue in a naturalistic patient setting. Because SAA activates Toll‐like receptors 2 and 4, present on macrophages and glial cells, its association with depression severity could also implicate this inflammatory mediator in the pathogenesis of mood disorders.