Sleep-Wake Disorders Unit, Department of Neurology, Gui-de-Chauliac Hospital, CHU Montpellier, Montpellier, France.
National Reference Network for Narcolepsy, CHU Montpellier, Montpellier, France.
Ann Clin Transl Neurol. 2020 Jun;7(6):924-931. doi: 10.1002/acn3.51056. Epub 2020 May 20.
To investigate whether cerebrospinal fluid (CSF) and serum ferritin levels differ between patients with narcolepsy type 1 (NT1) comorbid with restless legs syndrome (RLS) or periodic leg movements during sleep (PLMS), and patients with NT1 or controls without comorbid RLS or PLMS.
Sixty-six drug-free patients with NT1 (44 males, age 38.5 years [14-81]) were enrolled, including 20 with RLS, 18 with PLMS index ≥15/h (six with both RLS and PLMS). Thirty-eight drug-free patients (12 males, age 22.5 years [12-61]) referred for sleepiness complaint, but without central hypersomnia, RLS, PLMS were included as controls. Clinical, electrophysiological and biological (CSF/serum ferritin, orexin [ORX]) data were quantified.
NT1 patients with and without RLS did not differ for age, gender, and body mass index (BMI). No between-group differences were found for CSF ferritin, ORX, and serum ferritin levels. No CSF ferritin, ORX, and serum ferritin level differences were found between NT1 patients with and without PLMS, or with RLS or PLMS versus not. CSF-ferritin levels were not different between NT1 and controls in adjusted analyses. CSF-ferritin levels in the whole population correlated positively with age, serum-ferritin, BMI, negatively with ORX, but not with PLMS index. In NT1, CSF-ferritin levels correlated with age and serum-ferritin but not with PLMS.
The absence of CSF ferritin deficiency in NT1 with comorbid RLS or PLMS indicates normal brain iron levels in that condition. This result suggests that the frequent association between RLS, PLMS, and NT1 is not based on alterations in brain iron metabolism, a pathophysiological mechanism involved in primary RLS.
研究 1 型发作性睡病（NT1）合并不宁腿综合征（RLS）或睡眠周期性肢体运动（PLMS）与 NT1 患者或无合并 RLS 或 PLMS 的对照者之间脑脊液（CSF）和血清铁蛋白水平是否存在差异。
共纳入 66 例未服用药物的 NT1 患者（44 名男性，年龄 38.5 岁[14-81]），其中 20 例合并 RLS，18 例 PLMS 指数≥15/h（6 例同时合并 RLS 和 PLMS）。纳入 38 例因嗜睡症状就诊但无中枢性嗜睡、RLS、PLMS 的未服用药物的对照者（12 名男性，年龄 22.5 岁[12-61]）。量化了临床、电生理和生物学（CSF/血清铁蛋白、食欲素[ORX]）数据。
合并或不合并 RLS 的 NT1 患者在年龄、性别和体重指数（BMI）方面无差异。CSF 铁蛋白、ORX 和血清铁蛋白水平在各组之间无差异。NT1 患者中，合并或不合并 PLMS 患者，或合并 RLS 或 PLMS 患者与无合并症患者之间的 CSF 铁蛋白、ORX 和血清铁蛋白水平均无差异。调整分析显示，CSF 铁蛋白水平在 NT1 患者和对照组之间无差异。在全人群中，CSF 铁蛋白水平与年龄、血清铁蛋白呈正相关，与 ORX 呈负相关，但与 PLMS 指数无关。在 NT1 中，CSF 铁蛋白水平与年龄和血清铁蛋白相关，但与 PLMS 无关。
NT1 合并 RLS 或 PLMS 时 CSF 铁蛋白缺乏，表明脑内铁水平正常。这一结果表明，RLS、PLMS 和 NT1 之间的频繁关联并非基于脑铁代谢的改变，而脑铁代谢改变是原发性 RLS 的一种病理生理机制。
