Omori Yuki, Kanbayashi Takashi, Imanishi Aya, Tsutsui Ko, Sagawa Yohei, Kikuchi Yuka S, Takeshima Masahiro, Yoshizawa Kazuhisa, Uemura Sachiko, Shimizu Tetsuo
Department of Neuropsychiatry, Akita University Graduate School of Medicine, Akita, Japan.
International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan.
Neuropsychiatr Dis Treat. 2018 Feb 8;14:451-457. doi: 10.2147/NDT.S158651. eCollection 2018.
Myotonic dystrophy type 1 (DM1) is often characterized by excessive daytime sleepiness (EDS) and sleep-onset rapid eye movement periods caused by muscleblind-like protein 2. The EDS tends to persist even after treatment of sleep apnea. We measured the cerebrospinal fluid (CSF) orexin levels in DM1 patients with EDS and compared the clinical characteristics with narcolepsy type 1 and idiopathic hypersomnia (IHS) patients.
We measured the CSF orexin levels in 17 DM1 patients with EDS and evaluated subjective sleepiness using the Epworth Sleepiness Scale (ESS), objective sleepiness using mean sleep latency (MSL), and sleep apnea using apnea-hypopnea index (AHI). We compared the ESS scores and MSL between decreased (≤200 pg/mL) and normal (>200 pg/mL) CSF orexin group in DM1 patients. Furthermore, we compared the CSF orexin levels, ESS scores, MSL, and AHI among patients with DM1, narcolepsy type 1 (n=46), and IHS (n=30).
Seven DM1 patients showed decreased CSF orexin levels. There were significant differences in the ESS scores and MSL between decreased and normal CSF orexin groups in DM1 patients. The ESS scores showed no significant difference among patients with DM1, narcolepsy type 1, and IHS. The MSL in DM1 and IHS patients were significantly higher than narcolepsy type 1 patients (=0.01, <0.001). The AHI in DM1 patients was significantly higher than narcolepsy type 1 patients (=0.042) and was insignificantly different from IHS patients. The CSF orexin levels in DM1 patients were significantly lower than IHS patients and higher than narcolepsy type 1 patients (<0.001, <0.001).
The CSF orexin levels of DM1 patients moderately decreased compared to those of IHS patients as the control group. However, the EDS of DM1 patients may not be explained by only orexin deficiency.
1型强直性肌营养不良症（DM1）常表现为日间过度嗜睡（EDS）以及由肌肉失明样蛋白2引起的睡眠起始快速眼动期。即使在治疗睡眠呼吸暂停后，EDS仍往往持续存在。我们测量了患有EDS的DM1患者的脑脊液（CSF）食欲素水平，并将其临床特征与1型发作性睡病和特发性嗜睡症（IHS）患者进行比较。
我们测量了17例患有EDS的DM1患者的CSF食欲素水平，并使用爱泼华嗜睡量表（ESS）评估主观嗜睡程度，使用平均睡眠潜伏期（MSL）评估客观嗜睡程度，使用呼吸暂停低通气指数（AHI）评估睡眠呼吸暂停情况。我们比较了DM1患者中CSF食欲素水平降低（≤200 pg/mL）组和正常（>200 pg/mL）组之间的ESS评分和MSL。此外，我们比较了DM1患者、1型发作性睡病患者（n = 46）和IHS患者（n = 30）之间的CSF食欲素水平、ESS评分、MSL和AHI。
7例DM1患者的CSF食欲素水平降低。DM1患者中CSF食欲素水平降低组和正常组之间的ESS评分和MSL存在显著差异。DM1患者、1型发作性睡病患者和IHS患者之间的ESS评分无显著差异。DM1和IHS患者的MSL显著高于1型发作性睡病患者（P = 0.01，P < 0.001）。DM1患者的AHI显著高于1型发作性睡病患者（P = 0.042），与IHS患者无显著差异。DM1患者的CSF食欲素水平显著低于IHS患者且高于1型发作性睡病患者（P < 0.001，P < 0.001）。
与作为对照组的IHS患者相比，DM1患者的CSF食欲素水平适度降低。然而，DM1患者的EDS可能不能仅用食欲素缺乏来解释。
