[A marked decrease of orexin in the cerebrospinal fluid in a patient with myotonic dystrophy type 1 showing an excessive daytime sleepiness].
Excessive daytime somnolence is one of the common complaints in patients with myotonic dystrophy. Here we report a 60-year-old female case of myotonic dystrophy type 1 with narcolepsy due to medical condition. The size of the CTG repeat in the 3' untranslated region of the DMPK gene was 1,800-2,400 repeats. Brain MRI was normal. Polysomnography revealed sleep apnea and chronic alveolar hypoventilation. Multiple sleep latency tests revealed normal sleep latencies and sleep onset REM was not observed. Orexin/hypocretin in the cerebrospinal fluid was markedly decreased to an undetectable level. Such sleep-related disorders may worsen the quality of life and possibly cause sudden death in patients with myotonic dystrophy. Narcolepsy associated with myotonic dystrophy should be evaluated appropriately.
Iwata
Tomoaki
T
Department of Neurology, Tohoku University School of Medicine.
Suzuki
Naoki
N
Mizuno
Hideki
H
Nakashima
Ichiro
I
Kanbayashi
Takashi
T
Itoyama
Yasuto
Y
D005260:Female; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000134:cerebrospinal fluid*; D008875:Middle Aged; D009223:Myotonic Dystrophy / Q000134:cerebrospinal fluid* / Q000150:complications*; D009290:Narcolepsy / Q000209:etiology*; D009479:Neuropeptides / Q000134:cerebrospinal fluid*; D000068797:Orexins
D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D000068797:Orexins