The Perception and Attention Functions test battery as a measure of neurocognitive impairment in patients with suspected central disorders of hypersomnolence

Abstract

The aim of the current study was to evaluate an attention test as a discriminative tool to measure neurocognitive impairment in patients with disorders of hypersomnolence. Chronic excessive daytime sleepiness is the main symptom in central disorders of hypersomnolence. For diagnostic purposes and treatment evaluation, reliable assessment of excessive daytime sleepiness is required. Thirty-six patients with central disorders of hypersomnolence were compared with 20 healthy controls. All participants performed the 'Perception and Attention Functions' (WAF) of the Vienna Test System. Patients underwent polysomnography, Multiple Sleep Latency Test and Maintenance of Wakefulness Test. Patients were divided into two groups: (i) patients who met the criteria of disorder of hypersomnolence (objective excessive daytime sleepiness); and (ii) patients with subjective excessive daytime sleepiness, i.e. with normal Multiple Sleep Latency Test results. Group 1 consisted of 23 patients with objective excessive daytime sleepiness (11 with idiopathic hypersomnia, nine with narcolepsy type 1, three with narcolepsy type 2); group 2 included 13 patients with subjective excessive daytime sleepiness. The results showed cognitive impairment in patients with objective excessive daytime sleepiness and even in patients with subjective excessive daytime sleepiness. WAF tests identified distinct attention profiles in patients with narcolepsy type 1, idiopathic hypersomnia/narcolepsy type 2, and patients with subjective excessive daytime sleepiness. WAF test measures correlated with Maintenance of Wakefulness Test and the Epworth Sleepiness Scale, but not with Multiple Sleep Latency Test and the Fatigue Severity Scale. In conclusion, the multidimensional WAF test battery detects cognitive impairment even in patients that complain of excessive daytime sleepiness but have normal Multiple Sleep Latency Test results. WAF tests offer valuable information that adds to the existing polysomnographic measures in discriminating patients with different types of chronic excessive daytime sleepiness. The results provide new insights into cognitive dysfunction underlying different types of chronic excessive daytime sleepiness.

Cognitive dysfunction in central disorders of hypersomnolence: A systematic review

“…Thirty-five studies (73%) assessed a sample of untreated (either drug-naive or drug-free) CDH patients, 10 (21%) assessed a mixed sample of treated and untreated patients and three studies (6%) assessed patients under stable pharmacological treatment. Since Raam's study reported on a mixed population (NT2/IH), we decided to include this study in the IH section being the sample mostly composed by IH patients (10/13 were IH) [7].…”

“…Three studies used the d2 attention test. Naumann and Zamarian showed that NT1 patients processed fewer items compared to controls; Zamarian also reported increased errors in patients compared to controls [10,17] In the first study, the authors found more lapses in NT1 patients than in controls, but no difference emerged with IH patients and subjective EDS [7]. In the second study, the authors reported increased errors in NT1 patients compared to controls [19].…”

“…NT1 patients displayed slower and more variable RTs compared to controls and NT2 patients [13]. Ramm assessed tonic and phasic alertness in NT1, IH, controls and subjects who complained chronic EDS but did not fulfill the neurophysiological criteria for a CDH diagnosis (subjective EDS) [7]. NT1 patients displayed slower RTs in tonic but not in phasic alertness compared to controls.…”

“…Finally, Raam compared NT1 to IH, subjective EDS and controls. NT1 patients displayed slower RTs than controls and more errors compared to IH patients and controls [7]. Total sample assessed: 56 NT1 compared to 14 IH, 13 subjective EDS and 65 healthy controls.…”

Idiopathic Hypersomnia Patients Revealed Longer Circadian Period Length in Peripheral Skin Fibroblasts

“…Fifteen patients suffering from IH were consecutively recruited from the Department of Neurology, Division of Sleep Medicine and Neuromuscular Diseases at the University Hospital Muenster. Diagnosis was made according to standard criteria of the ICSD-3 ( 1 ) as described recently ( 23 ). The Epworth Sleepiness Score (ESS) to assess subjective daytime sleepiness ( 24 ) had to be above 10 and the Horne-Ostberg (HO) score was evaluated by the self-assessment HO questionnaire ( 25 ).…”