BACKGROUND Narcolepsy is a sleep disorder characterized by a loss of hypocretin neurons in the hypothalamus. Inflammation is proposed as a mechanism for neurodegeneration in narcolepsy. Numerous studies have investigated peripheral cytokine measures in narcoleptic patients, though the results are not conclusive. The current systematic review and meta-analysis aims to address the question of how do serum/plasma cytokine levels change in narcolepsy. METHODS A systematic search of the literature to July 2019, was conducted to identify studies that measured cytokine levels in patients with narcolepsy, compared with those in controls without narcolepsy. RESULTS Twelve studies were included in the meta-analysis: ten for interleukin (IL)-6, five for IL-8, three for IL-10, and ten for tumor necrosis factor alpha (TNF-α). Compared with controls, patients with narcolepsy had higher plasma levels of IL-6 (95% CI [0.22, 3.74]; P = 0.03) and TNF-α (95% CI [0.53, 4.18]; P = 0.01), while did not significantly differ in plasma IL-8 (95% CI [-1.64, 2.08]; P = 0.82) and IL-10 (95% CI [-1.29, 0.72]; P = 0.57) as well as serum IL-6 (95% CI [-1.48, 0.32], P = 0.21) and TNF-α (95% CI [-3.14, 0.19], P = 0.08) and CSF IL-8 (95% CI [-1.16, 0.41]; P = 0.35) levels. Patients with narcolepsy exhibited lower CSF IL-6 (95% CI [-0.66, 0.06]; P = 0.02) levels comparing with controls. CONCLUSIONS Patients with narcolepsy had elevated plasma levels of IL-6 and TNF-α and lower levels of CSF IL-6 than non-narcoleptic controls. Our results support the role of inflammation in the pathophysiology of narcolepsy. However, plasma levels of IL-8 and IL-10, serum levels of IL-6 and TNF-α and CSF IL-8 did not significantly differ between patients and controls.

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发作性睡病中的细胞因子：系统评价和荟萃分析

背景发作性睡病是一种睡眠障碍，其特征在于下丘脑中的下丘脑分泌素神经元丢失。炎症被认为是发作性睡病神经变性的一种机制。许多研究调查了发作性睡病患者的外周细胞因子测量，但结果尚无定论。当前的系统评价和荟萃分析旨在解决发作性睡病中血清/血浆细胞因子水平如何变化的问题。方法 对截至 2019 年 7 月的文献进行了系统搜索，以确定测量发作性睡病患者细胞因子水平的研究，与没有发作性睡病的对照组相比。结果 荟萃分析包括 12 项研究：白细胞介素 (IL)-6 的 10 项、IL-8 的 5 项、IL-10 的 3 项和肿瘤坏死因子 α (TNF-α) 的 10 项。与对照相比，发作性睡病患者的血浆 IL-6 (95% CI [0.22, 3.74]; P = 0.03) 和 TNF-α (95% CI [0.53, 4.18]; P = 0.01) 水平较高，但在血浆 IL-8 (95% CI [-1.64, 2.08]; P = 0.82) 和 IL-10 (95% CI [-1.29, 0.72]; P = 0.57) 以及血清 IL-6 (95% CI [ -1.48, 0.32], P = 0.21) 和 TNF-α (95% CI [-3.14, 0.19], P = 0.08) 和 CSF IL-8 (95% CI [-1.16, 0.41]; P = 0.35) 水平. 与对照组相比，发作性睡病患者的 CSF IL-6（95% CI [-0.66, 0.06]；P = 0.02）水平较低。结论与非发作性睡病患者相比，发作性睡病患者的血浆 IL-6 和 TNF-α 水平升高，脑脊液 IL-6 水平降低。我们的结果支持炎症在发作性睡病的病理生理学中的作用。然而，血浆 IL-8 和 IL-10 水平，