Inflammatory Hematological Ratios in the Diagnosis and Assessment of Clinical Characteristics in Patients with Depressive Episodes: A Systematic Review
Abstract
Background. The monoamine theory does not cover the full range of biological mechanisms of depression that underlie it. Current evidence highlights the role of systemic inflammation, with inflammatory hematological ratios (IHR) being considered as accessible and cost-effective markers of inflammatory status.
Aim — to summarize the results of studies of IHR in patients with depressive episodes within affective spectrum disorders.
Methods. A protocol was developed and registered in the PROSPERO database. Electronic databases (MEDLINE, Cochrane Library, eLIBRARY.RU, CyberLeninka, RusMed) were searched and articles were selected. We included articles that investigated the values of IHR in patients with diagnosed depression. The quality of the selected studies was assessed using the NHLBI Quality Assessment Tool.
Results. A total of 1,976 articles were identified, with 35 included in the final analysis. Most of them demonstrate statistically significant increases in IHR levels in depressed patients compared to controls. Associations have been found between IHR levels and clinical characteristics of disorders, including the type of affective pathology (monopolar or bipolar depression) and the severity of the depressive episode. There is insufficient evidence for the use of IHR as diagnostic or prognostic biomarkers. The association of IHR with components of the metabolic syndrome has not been addressed in most studies; a limited number of studies indicate a positive correlation of IHR with body mass index.
Conclusions. Inflammatory hematological ratios represent a promising tool for assessing clinical characteristics of affective disorders. Further research is needed to clarify their prognostic value and their relationship with metabolic disturbances.
Keywords
inflammation, biomarkers, systematic review, depression, bipolar disorder, body mass index, inflammatory hematological ratios
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