Abstract
Background: Currently, increasing evidence supports the hypothesis that alterations in the immune-inflammatory system are critical for the pathophysiology of bipolar disorder (BD). Neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), monocyte/lymphocyte ratio (MLR), and mean platelet volume (MPV) have recently been investigated as inexpensive and simple inflammatory markers.
Aims: The aim of this study is to compare NLR, PLR, MLR, and MPV in depressive, manic, and euthymic patients with BD and healthy controls, and to evaluate whether values of NLR, PLR, MLR, and MPV are possible state or trait biomarkers in BD.
Methods: This retrospective study was conducted with 341 patients with BD (100 patients in a depressive state, 141 patients in a manic state, and 100 patients in a euthymic state) and 114 healthy controls.
Results: We found that patients with BD in manic states had higher levels of MPV, NLR, and MLR, and patients with BD in depressive states had higher levels of MPV than the controls. Moreover, MPV predicted all states of BD, while NLR and MLR predicted the manic state of BD.
Conclusions: NLR, MLR, and MPV obtained from simple and inexpensive blood tests were significantly higher in patients with BD than in healthy controls, which each imply low-grade inflammation. MPV may serve as a possible trait biomarker of BD, while NLR and MLR may both serve as possible state biomarkers of the manic state.
Disclosure statement
None of the authors has any conflict of interest to disclose.
Additional information
Notes on contributors
Ikbal Inanli
Ikbal Inanli, Clinic of Psychiatry, Konya Research and Training Hospital, University of Health Sciences, Konya, Turkey
Memduha Aydin
Memduha Aydin, Department of Psychiatry, Faculty of Medicine, Selcuk University, Konya, Turkey
Ali Metehan Çaliskan
Ali Metehan Caliskan, Clinic of Psychiatry, Konya Research and Training Hospital, University of Health Sciences, Konya, Turkey
Ibrahim Eren
Ibrahim Eren, Clinic of Psychiatry, Konya Research and Training Hospital, University of Health Sciences, Konya, Turkey