Are serum levels of inflammatory markers associated with the severity of symptoms of bipolar disorder?

Abstract

BackgroundTo explore the relationship between serum levels of inflammatory markers and symptomatic severity of bipolar disorder (BD).Materials and methodsA cross-sectional study was conducted on 126 BD patients with current depressive episode (BDD), 102 BD patients with current mixed or (hypo)manic episode (BDM) and 94 healthy controls (HC). All participants were drug-naïve and had no current active physical illness associated with inflammatory response or history of substance abuse. Fasting serum levels of CRP, leptin (LEP), adiponectin (ADP), visfatin (VIS), TNF-α, IL-2, IL-6, IL-10, IL-17), and monocyte chemoattractant protein-1 (MCP-1) were measured with enzyme-linked immunosorbent assay (ELISA). Symptomatic severity of BD was assessed with HAMD-17 and YMRS. Generalized linear model was used to determine the association between the serum levels of inflammatory markers and symptomatic severity of BD.ResultsThe serum levels of IL-6, IL-10 and IL-17, and the IL-6/IL-10 ratio were significantly lower in mild BDD than in HC. In moderate BDD, the serum levels of MCP, IL-6 and IL-17 were significantly lower than in HC. In severe BDD, the serum level of ADP, MCP-1, IL-10 and IL-17and the IL-17/IL-10 ratio were significantly lower than in HC. The serum levels of TNF-α and the IL-6/IL-10 ratio were significantly higher in mild BDM than in HC. In moderate BDM, the serum level of VIS, IL-2, and IL-17 were significantly higher than in HC, but the IL-6/IL-10 ratio was significantly lower than in control. In severe BDM, the serum levels of IL-6 and IL-17 and the ratios of IL-6/IL-10 and IL-17/IL-10 were significantly lower than in HC, but the neutrophil/lymphocyte ratio was significantly higher than in HC.ConclusionIn BDD, immune-inhibition is persistently predominant, while in mild-to-moderate BDM, immune system is activated but inhibited in severe BDM. The dynamic change of serum inflammatory markers suggests that alteration of peripheral inflammatory markers in BD is state-dependent instead of trait-marked.

Plasma IGFBP-3 and IGFBP-5 levels are decreased during acute manic episodes in bipolar disorder patients

“…Nonetheless, in the same patients, the levels of MCP-1 did not change over time ( Edberg et al, 2020 ). Recently, the levels of MCP-1 were found significantly reduced in both moderate and severe depressive BD but not in manic BD patients ( Wu et al, 2023 ). To some extent, more studies may be needed in the field to shed light on whether peripheral monocyte activation through MCP-1 levels is increased in BD patients and whether this alteration is related to acute mood states rather than BD itself.…”

Metabolic Syndrome and Adipokines Profile in Bipolar Depression

“…Decreased ADIPO levels in patients with obesity [40], coronary heart disease, diabetes, and hypertension demonstrate a high tendency to develop MS [3]. Moreover, patients with BP during the depression episode showed decreased levels of ADIPO [42][43][44]. Obesity and MS are characterized by increased leptin and decreased adiponectin concentration [6,45].…”

Older age bipolar disorder

“…There is a need for subtyping (profiling) OABD patients to reduce this heterogeneity and to improve personalized treatment. Markers of illness severity that have previously been suggested for bipolar disorder patients of all ages are (among others): bipolar disorder subtype I [ 14 ], presence of psychotic symptoms [ 15 ], childhood maltreatment [ 16 ], predominant polarity, episode density [ 17 ], and presence of neuroinflammation [ 18 , 19 ].…”