Jerome Vialaret, Christophe Hirtz, Manuela Lotierzo, Lucie Barateau, Paul Cristol Jean, Jerome Tanty, Isabelle Jaussent, Sylvain Lehmann, Yves Dauvilliers
LBPC-PPC, University of Montpellier, INM INSERM, IRMB CHU de Montpellier, Montpellier, France.
Institute of Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France.
Sleep. 2025 Aug 13. doi: 10.1093/sleep/zsaf237.
Cerebrospinal fluid (CSF) hypocretin-1/orexin-A quantification via radioimmunoassay (RIA) is used for diagnosing narcolepsy type 1(NT1), but its limitations require alternative methods. Using liquid chromatography-mass spectrometry (LC-MS), this study aimed to 1/fully characterize CSF orexin-A fragments detected by the gold standard RIA method, and 2/assess diagnostic relevance of measuring the most prevalent fragment, a 16-mer, in patients with NT1, narcolepsy type 2(NT2), idiopathic hypersomnia (IH) and non-specified hypersomnolence (NSH).
CSF samples were analyzed using RIA and LC-MS in patients with hypersomnolence disorders evaluated at the French Narcolepsy National Reference Center. Fractionation techniques isolated orexin-A and its fragments, which were identified via targeted MS. Statistical analysis compared LC-MS performance against RIA.
CSF samples from 115 patients (54.8% females, mean age 30.4 ± 15.8 years) including 52 with NT1, 6 NT2, 13 IH, 44 NSH were analyzed by RIA and LC-MS. A 16-mer orexin-A fragment was identified and quantified by LC-MS, with lower levels in NT1. This fragment correlated strongly with RIA-measured orexin-A (r = 0.83,p<.0001) and demonstrated high sensitivity (98.1%) and specificity (85.7%) for diagnosis of NT1. Receiver operating characteristics analyses confirmed the high performance with Area Under the Curve of 0.975 and an optimal diagnostic cutoff of 10.67 pg/mL for LC-MS.
The 16-mer orexin-A peptide represents a promising biomarker that could in the future help in the diagnosis of central hypersomnolence disorders. The transition from RIA to LC-MS methods for the quantification of 16-mer orexin-A represents a critical advance toward improving diagnostic accuracy and understanding orexinergic dysfunction in sleep disorders.
通过放射免疫分析（RIA）对脑脊液（CSF）中的下丘脑分泌素-1/食欲素-A进行定量分析，用于诊断1型发作性睡病（NT1），但其局限性需要替代方法。本研究采用液相色谱-质谱联用（LC-MS）技术，旨在：1/全面表征金标准RIA方法检测到的脑脊液食欲素-A片段；2/评估测量最常见的片段（一种16聚体）对NT1、2型发作性睡病（NT2）、特发性嗜睡症（IH）和非特异性嗜睡症（NSH）患者的诊断相关性。
在法国发作性睡病国家参考中心对患有嗜睡症的患者的脑脊液样本进行RIA和LC-MS分析。分级分离技术分离出食欲素-A及其片段，通过靶向质谱进行鉴定。统计分析将LC-MS的性能与RIA进行比较。
对115例患者（54.8%为女性，平均年龄30.4±15.8岁）的脑脊液样本进行了RIA和LC-MS分析，其中包括52例NT1患者、6例NT2患者、13例IH患者、44例NSH患者。通过LC-MS鉴定并定量了一种16聚体食欲素-A片段，NT1患者中的水平较低。该片段与RIA测量的食欲素-A高度相关（r = 0.83，p <.0001），对NT1诊断具有高敏感性（98.1%）和特异性（85.7%）。受试者工作特征分析证实了其高性能，曲线下面积为0.975，LC-MS的最佳诊断临界值为10.67 pg/mL。
16聚体食欲素-A肽是一种有前景的生物标志物，未来可能有助于中枢性嗜睡症的诊断。从RIA方法过渡到LC-MS方法对16聚体食欲素-A进行定量分析，是提高诊断准确性和理解睡眠障碍中食欲素能功能障碍的关键进展。
