Comparison of serum BDNF, S100B levels of patients with bipolar disorder in manic and remission periods with healthy volunteers and evaluation of results with neuropsychological tests

Aim: In this study, we aim to contribute to the literature by comparing the serum BDNF, S100B levels of patients with bipolar disorder during the mania and remission periods with healthy volunteers and evaluating the results with neuropsychological tests. Material and Method: 25 patients (attacks-remission period) who were diagnosed with bipolar disorder according to DSM 5 diagnostic criteria and 25 healthy volunteers were included in this study. The physician filled out the sociodemographic data form of the patient and healthy control group. To assess the serum BDNF ((Brain Derived Neurotrophic Factor) and S100B levels, blood samples were collected before and after treatment. YMRC (Young Mania Rating Scale), HRSD (Hamilton Rating Scale for Depression ), and GDO (Global Rating Scale) scales were applied before and after treatment. Stroop and digit span tests were performed as neuropsychological tests. Results: We found the level of BDNF and S100B in the patient group during manic attacks significantly lower than in the control group. Also, the BDNF level during the attack was significantly lower than the level of remission. We found a positive correlation between the BDNF and the S100B values. Stroop 1, Stroop 2, Stroop 4, Stroop 4 error number, Stroop 4 spontaneous correction, and Stroop 4 time difference were significantly higher than the control group. Lastly, the deterioration rate of the patient group at Stroop 4 was significantly higher than the ratio of the control group. Conclusion: Our study demonstrated that only BDNF levels tend to rise significantly during the attack and remission period. BDNF levels may be indirectly but not directly related to the physiopathology of bipolar disorder or may be a marker of attack in general but not specific to manic episodes. Therefore, more detailed and long- term studies, including different episodes of the same patient group are needed to make such a determination. The results obtained so far do not yet allow a definite assessment of these issues. In our study, we found that BDNF and S100B levels generally moved in the same direction and we think this was mediated by their neurotrophic/neuroprotective effects. We also found a positive correlation between serum BDNF and S100B levels and cognitive well-being. Key Words: Bipolar Disorder, BDNF, S100B, Neuropsychological Test