目的·探索血清白介素-6（interleukin-6，IL-6）水平与精神分裂症伴抑郁症状之间的关系。方法·招募239例使用奥氮平单药治疗2年以上的精神分裂症患者。采用卡尔加里精神分裂症抑郁量表（Calgary Depression Scale for Schizophrenia，CDSS）评估患者的抑郁水平，并将其分为伴抑郁组和不伴抑郁组。采用阳性与阴性症状量表（Positive and Negative Syndrome Scale，PANSS）评估患者的精神症状。采用酶联免疫吸附测定（enzyme linked immunosorbent assay，ELISA）检测血清IL-6水平，并进行组间比较。采用Pearson相关分析检验血清IL-6水平与CDSS评分之间的关系。结果·依据CDSS评分结果将患者分为伴抑郁组（119例）和不伴抑郁组（120例）。与不伴抑郁组相比，伴抑郁组患者的PANSS阴性症状分量表评分、血清IL-6水平均较高（P=0.028，P=0.000）。经Pearson相关分析显示，伴抑郁组患者的血清IL-6水平与CDSS评分呈正相关（r=0.42，P=0.000）。结论·血清IL-6水平增高可能与精神分裂症伴抑郁症状的发生有关。

Objective · To explore the relationship between serum interleukin-6 (IL-6) level and depressive symptoms in schizophrenia. Methods · A total of 239 patients with schizophrenia treated with olanzapine alone for more than 2 years were enrolled. Calgary Depression Scale for Schizophrenia (CDSS) was used to evaluate the depression level of the patients, and they were divided into depression group and non-depression group. Positive and Negative Syndrome Scale (PANSS) was used to evaluate the mental symptoms of patients. Serum IL-6 levels were measured by enzyme linked immunosorbent assay (ELISA), and the differences between the two groups were compared. Pearson correlation analysis was used to analyze the relationship between serum IL-6 level and CDSS score. Results · According to the results of CDSS, the patients were divided into depression group (119 cases) and non-depression group (120 cases). Compared with the non-depression group, the PANSS negative symptom subscale score and serum IL-6 level of patients in the depression group were higher (P=0.028, P=0.000). Pearson correlation analysis showed that serum IL-6 level was positively correlated with CDSS score in the depression group patients (r=0.42, P=0.000). Conclusion · The increase of serum IL-6 level may be related to the occurrence of schizophrenia with depression symptoms.