Sleep microstructure in Parkinson's disease: cycling alternating pattern (CAP) as a sensitive marker of early NREM sleep instability.

BACKGROUND: Sleep disorders are frequent in Parkinson's disease (PD). Apart from the occurrence of REM behavior disorders, in the early phase of the disease standard sleep macrostructure evaluation was inconclusive. OBJECTIVE: We analyzed non-rapid eye movement (NREM) sleep microstructure (CAP) in a group of PD patients to provide an objective measure of sleep disruption. METHODS: We recruited 31 PD patients [mean age 59.5 ± 12.4 years; mean Hoehn-Yahr (H-Y) stage: 3.4 ± 1.8] and 34 age-matched non-parkinsonian subjects (mean age 61.5 ± 15.2 years) as a control group. All patients underwent full-night laboratory polysomnography (PSG). Conventional sleep macro/microstructure analysis was performed. Patients were then divided into two groups: group 1 (H-Y stage ≤ 2) and group 2 (H-Y stage ≥ 3). RESULTS: In group 2 PD patients compared to controls, alterations of both sleep macrostructure and microstructure were found. The PD subgroup with milder disease (group 1) presented sleep macrostructure, movements and respiratory parameters not significantly different from controls, although their CAP rate was significantly higher and the proportion of the A1 phase of CAP was reduced (p = 0.03). Multivariate logistic regression showed that disease duration, disease severity, and arousal index emerged as independent predictive factors for CAP rate ≥55% and the A1 phase of CAP ≤40% (p < 0.05). CONCLUSION: The main result of our study consists in the disclosure of altered NREM sleep microstructure in PD even at an early stage of the disease, suggesting an early alteration of the central pathways involved in the NREM sleep building-up and stability.

EEG alpha asymmetry in virtual environments for the assessment of stress-related disorders.

In this study we consider neurophysiological aspects for the assessment of stress-related disorders. EEG Alpha Asymmetry could represent an effective method to be used in the virtual environment. Nonetheless, new protocols need to be defined. In this study herein, we present two methods and a case study.

A new NOTCH3 mutation presenting as primary intracerebral haemorrhage.

Primary intracerebral haemorrhages (PICH) are defined as haemorrhages within the brain parenchyma in the absence of readily identifiable causes. CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy) is a hereditary vascular disease and its mainly clinical manifestations are early-onset infarcts. Spontaneous lobar haematomas are a rare occurrence. We report a very unusual presentation of CADASIL in a 65 year-old man carrying a new NOTCH3 mutation. The clinical onset of the disease was related to an intracerebral haematoma following colon surgery and causing a delirium. In brief, our report suggests that CADASIL must be considered in patient with PICH.

On the origin of sensory impairment and altered pain perception in Prader-Willi syndrome: a neurophysiological study.

INTRODUCTION: High pain threshold is a supportive diagnosis criterion for Prader-Willi syndrome (PWS), but its pathogenesis is poorly understood. In this study we investigate sensory pathways in PWS, in order to evaluate peripheral or central involvement in altered sensory perception. METHODS: 14 adult PWS patients, 10 obese non-diabetic people and 10 age-matched controls underwent: (a) motor/sensory nerve conduction velocities at the upper and lower limbs; (b) palmar/plantar sympathetic skin response; (c) somatosensory evoked potentials from upper/lower limbs; (d) quantitative sensory testing to measure sensory threshold for vibration, warm and cold sensation, heat and cold-induced pain and (e) blood sample analysis to evaluate glucose and insulin levels and to calculate the quantitative insulin-sensitivity check index (QUICKI). RESULTS: Electroneurographic examination, sympathetic skin response and somatosensory evoked potentials were all within normal ranges. In the PWS group, thermal and pain thresholds but not vibratory were significantly higher than in healthy and obese people (p<0.05). Sensory threshold did not correlate with BMI nor with QUICKI. CONCLUSIONS: Our data suggest that altered perception in PWS does not seem attributable to a peripheral nerve derangement due to metabolic factors or obesity. Impairment of the small nociceptive neurons of dorsal root ganglia or involvement of hypothalamic region may not be excluded.