Sandberg Asbjørn Arnesen, Steen Vidar M, Torsvik Anja
Norwegian Centre for Mental Disorders Research (NORMENT), Department of Clinical Science, University of Bergen, Bergen, Norway.
Dr. Einar Martens Research Group for Biological Psychiatry, Department of Medical Genetics, Haukeland University Hospital, Bergen, Norway.
Front Psychiatry. 2021 Sep 16;12:728990. doi: 10.3389/fpsyt.2021.728990. eCollection 2021.
Several studies have found an association between elevated neutrophil count or neutrophil-to-lymphocyte ratio (NLR) in peripheral blood from patients with schizophrenia. The etiology behind this effect is unknown, and it is unclear if changes in neutrophil count and NLR may be induced by antipsychotics or if these parameters relate to the diagnosis and symptoms of schizophrenia. The purpose of this scoping review was to map research that explores this association, and to identify gaps in the current knowledge base. The work was conducted in accordance with established methodological standards for scoping reviews. Studies on neutrophil count and NLR in schizophrenia were identified through search in relevant databases, and a parallel screening procedure was performed to ensure validity and reproducibility of the search. Articles that included different comparison groups, with differences in medication status (drug-naïve or drug-free vs. medicated), current disease state (relapse vs. remission), or treatment response, were included, as well as studies evaluating the association between symptomatology and neutrophil count or NLR. The available literature was limited with substantial differences in aims, methods, and outcomes. In total, 13 articles were included for the synthesis of this review. Some interesting trends were identified: Neutrophil count and NLR seem to be elevated in schizophrenia patients regardless of current or past use of antipsychotic therapy. Neutrophil count and NLR correlated significantly with positive symptoms of schizophrenia. Still, these findings should be interpreted with caution due to considerable methodological differences and weaknesses in the literature, particularly concerning the blood sampling procedure. By including longitudinal studies and by comparing patient groups based on medication status, disease state and response, our study provides a basis for dissecting the associations between increased neutrophil count or NLR and a diagnosis of schizophrenia. Further research should investigate and quantify the apparent strong correlation between neutrophil count or NLR and positive symptoms in schizophrenia, to evaluate its clinical potential to guide diagnostics, treatment, or as a predictor of outcome. This review also exposes important methodological weaknesses in the literature on neutrophil count and NLR measurements. Standardization of blood sampling and processing is crucial to reduce bias, and factors that are known to influence leukocyte levels need to be accounted for.
多项研究发现，精神分裂症患者外周血中性粒细胞计数升高或中性粒细胞与淋巴细胞比值（NLR）之间存在关联。这种效应背后的病因尚不清楚，中性粒细胞计数和NLR的变化是否由抗精神病药物引起，或者这些参数是否与精神分裂症的诊断和症状相关也不明确。本综述的目的是梳理探索这种关联的研究，并找出当前知识库中的空白。这项工作是按照既定的综述方法标准进行的。通过在相关数据库中检索，确定了关于精神分裂症中性粒细胞计数和NLR的研究，并进行了平行筛选程序，以确保检索的有效性和可重复性。纳入了包括不同比较组的文章，这些比较组在用药状态（未用药或停药与用药）、当前疾病状态（复发与缓解）或治疗反应方面存在差异，以及评估症状学与中性粒细胞计数或NLR之间关联的研究。现有文献有限，在目的、方法和结果方面存在很大差异。本综述共纳入13篇文章进行综合分析。发现了一些有趣的趋势：无论当前或过去是否使用抗精神病治疗，精神分裂症患者的中性粒细胞计数和NLR似乎都会升高。中性粒细胞计数和NLR与精神分裂症的阳性症状显著相关。然而，由于文献中存在相当大的方法学差异和缺陷，特别是在血液采样程序方面，这些发现应谨慎解读。通过纳入纵向研究，并根据用药状态、疾病状态和反应对患者组进行比较，我们的研究为剖析中性粒细胞计数或NLR升高与精神分裂症诊断之间的关联提供了基础。进一步的研究应调查并量化中性粒细胞计数或NLR与精神分裂症阳性症状之间明显的强相关性，以评估其在指导诊断、治疗或作为预后预测指标方面的临床潜力。本综述还揭示了关于中性粒细胞计数和NLR测量的文献中重要的方法学缺陷。血液采样和处理的标准化对于减少偏差至关重要，需要考虑已知影响白细胞水平的因素。
