Comparison of serum BDNF, IL-1β, IL-6, TNF-α, CRP and leucocyte levels in unipolar mania and bipolar disorder

Abstract

Objective: Unipolar mania is not included in the DSM-5 as a separate diagnosis, although it is defined by widely accepted diagnostic criteria. The aim of this study was to investigate the differences between unipolar mania and bipolar disorder in terms of clinical and inflammatory parameters. Methods: The data of 495 hospitalized patients with bipolar disorder diagnoses were analyzed retrospectively. Forty met the diagnostic criteria for unipolar mania. Two patients refused to participate in the study. Thirty-eight unipolar mania patients and forty-two randomly selected patients with bipolar disorder diagnosis were included in the study. The two groups were compared in terms of sociodemographic, clinical characteristics, serum brain-derived neurotrophic factor, C-reactive protein, leukocyte, and cytokine levels. Results: A total of 40 (8.08%) of 495 patients diagnosed with bipolar disorder met the unipolar mania diagnostic criteria. The number of manic episodes and the number of hospitalisations were statistically higher in the unipolar mania group than in the bipolar disorder group. Among all the manic symptoms, the incidence of symptoms such as euphoria, increased sexual interest, grandiosity, and delusions were found to be statistically higher in the unipolar mania group. Interleukin-6 and C-reactive protein levels were significantly higher in the unipolar mania group than in the bipolar disorder group. Conclusion: Unipolar mania differs from bipolar disorder in terms of clinical features and serum interleukin-6 and C-reactive protein levels.

Characterizing the clinical profile of mania without major depressive episodes: a systematic review and meta-analysis of factors associated with unipolar mania

“…Twenty-one studies met the eligibility criteria and were included in the meta-analysis (Aghanwa, 2001 ; Akarsu et al, 2012 ; Amamou et al, 2018 ; Andrade-Nascimento, Miranda-Scippa, Nery-Fernandes, Kapczinski, & Quarantini, 2011 ; Angst, Gerber-Werder, Zuberbühler, & Gamma, 2004 ; Angst et al, 2019 ; Beesdo et al, 2009 ; Chang et al, 2022 ; Dakhlaoui, Essafi, & Haffani, 2008 ; Gorgulu, Uluturk, & Palabiyik, 2021 ; Grobler, Roos, & Bekker, 2014 ; Grover et al, 2021 ; Mittal, Mehta, Solanki, Swami, & Meena, 2013 ; Perugi et al, 2007 ; Rajkumar, 2016 ; Sangha et al, 2022 ; Sonkurt, Altınöz, Danışman Sonkurt, & Köşger, 2021 ; Stokes et al, 2020 ; Subramanian, Kattimani, Rajkumar, Bharadwaj, & Sarkar, 2016 ; Yazıcı & Çakır, 2012 ; Yazici et al, 2002 ). The flowchart with details on screening and study selection process is reported in Fig.…”

“…In terms of age comparability between UM and md-BD, 10 studies met the quality criterion (Akarsu et al, 2012 ; Beesdo et al, 2009 ; Chang et al, 2022 ; Gorgulu et al, 2021 ; Perugi et al, 2007 ; Rajkumar, 2016 ; Sangha et al, 2022 ; Sonkurt et al, 2021 ; Stokes et al, 2020 , UK cohort; Subramanian et al, 2016 ). On the contrary, illness duration comparability was warranted by the majority of studies, with just a few with unclear data (Grobler et al, 2014 ; Grover et al, 2021 ; Sangha et al, 2022 ; Yazıcı & Çakır, 2012 ) or a mean difference over 3 years between groups (Aghanwa, 2001 ; Andrade-Nascimento et al, 2011 ; Perugi et al, 2007 ; Sonkurt et al, 2021 ; Stokes et al, 2020 , France cohort).…”

“…Most of the included studies were sufficiently representative, apart from one involving only subjects with disease onset during adolescence (Beesdo et al, 2009 ) and another which sampled also people with non-BD diagnoses (Grobler et al, 2014 ), respectively. Finally, in terms of UM diagnosis, 11 included studies considered the threshold of at least three lifetime manic episodes (Aghanwa, 2001 ; Akarsu et al, 2012 ; Amamou et al, 2018 ; Gorgulu et al, 2021 ; Grobler et al, 2014 ; Grover et al, 2021 ; Perugi et al, 2007 ; Sonkurt et al, 2021 ; Stokes et al, 2020 ; Yazıcı & Çakır, 2012 ; Yazici et al, 2002 ) and 12 the minimum period of observation of 4 years to define UM (Aghanwa, 2001 ; Andrade-Nascimento et al, 2011 ; Angst et al, 2004 ; Beesdo et al, 2009 ; Dakhlaoui et al, 2008 ; Gorgulu et al, 2021 ; Grover et al, 2021 ; Perugi et al, 2007 ; Sonkurt et al, 2021 ; Stokes et al, 2020 ; Yazıcı & Çakır, 2012 ; Yazici et al, 2002 ). The risk of bias assessment of included studies is reported in online Supplementary File 2.…”

Shifting levels of peripheral inflammatory profiles as an indicator for comorbid multiple autoimmune diseases and bipolar disorder: a case report

“…Evidence has shown elevated levels of cytokines, such as TNF-α, interferon γ (IFN-γ), IL [ 12 ], complement cascade components [ 13 ], immunoglobulin [ 14 ], and inflammatory indicators such as CRP [ 15 , 16 ], in BD patients compared with healthy controls. Moreover, patients with unipolar mania showed higher serum levels of IL-6 and CRP than other patients with a BD diagnosis [ 17 ]. In this case, our patient showed increased levels of CRP, complement C3 and C4, and proinflammatory cytokines such as IFN-γ, IL-4, and IL-6.…”

The Diagnostic Concept of Unipolar Mania

“…They seem to perform worse in visual memory and executive functions and show specific social cognition deficits (Sonkurt et al, 2022). Moreover, based on the evidence that bipolar spectrum disorders might be associated with specific peripheral biomarkers (e.g., Bartoli et al, 2022;Carvalho et al, 2020), a distinct inflammatory status was hypothesized in people with UM, characterized by higher serum levels of interleukin 6 and C-reactive protein (Gorgulu et al, 2021).…”