Validation of the ICSD-2 Criteria for CSF Hypocretin-1 Measurements in the Diagnosis of Narcolepsy in the Danish Population

Abstract

The study provides evidence that hypocretin deficiency causes a more severe NC phenotype. The ICSD-2 criterion for low CSF hcrt-1 (< 30% of normal mean) is valid for diagnosing NC, but not NwC. HLA-typing should precede CSF hcrt-1 measurements because hypocretin deficiency is rare in HLA-DQB1*0602-negative patients.

Clinical and polysomnographic characteristics in 20 North Indian patients with narcolepsy: A seven-year experience from a neurology service sleep clinic

“…In the study by Bassetti et al, [14] in the US, the mean age of patients was 46 years for patients with narcolepsy with cataplexy and 34 years for monosymptomatic narcolepsy, while other studies from Netherlands and Japan reported a mean age of 34 and 29, respectively. [15,16] In our series, there was male gender predominance (18:2) as compared to the gender distribution in other published case series. [14][15][16] In population-based studies, narcolepsy has been found to be 1.6 times more common in the male population.…”

“…[15,16] In our series, there was male gender predominance (18:2) as compared to the gender distribution in other published case series. [14][15][16] In population-based studies, narcolepsy has been found to be 1.6 times more common in the male population. [17] In the series reported from Singapore, the male: female ratio was 5.5.…”

Sleep-stage transitions during polysomnographic recordings as diagnostic features of type 1 narcolepsy

“…Polysomnographic (PSG) features include an instability of the sleep-wake cycle together with daytime sleepiness, short sleep latency, fragmented nocturnal sleep, and abnormal rapid eye movement (REM) sleep with a shortened REM sleep latency during nocturnal sleep and daytime naps, and events of dissociated REM sleep [1][2][3]. The disease is caused by the loss of approximately 50-70,000 hypocretin-producing neurons in the hypothalamus, resulting in negligible levels of hypocretin-1, a wake-promoting peptide, in the CSF [4][5][6][7][8]. The lack of hypocretin is causative to the disorder as animals mutated for hypocretin receptors or lacking the hypocretin ligand have narcolepsy [9,10].…”

Identification of the Variations in the CPT1B and CHKB Genes Along with the HLA-DQB1*06:02 Allele in Turkish Narcolepsy Patients and Healthy Persons

“…Currently, hypocretin is used as a diagnostic marker for narcolepsy. It was also suggested that HLA-typing should precede CSF hypocretin-1 measurements because hypocretin deficiency is rare in HLA-DQB1*06:02-negative patients (Knudsen et al, 2010).…”