Elena Colizzi

Distinctive polysomnographic traits in nocturnal frontal lobe epilepsy.

Purpose:  To describe the polysomnographic features and distribution of epileptic motor events, in relation to conventional sleep measures and cyclic alternating pattern (CAP) parameters, in 40 untreated patients with nocturnal frontal lobe epilepsy (NFLE).

Stress hormones, sleep deprivation and cognition in older adults

Cognition can be deteriorated in older persons because of several potential mechanisms including the hormonal changes occurring with age. Stress events cause modification in hormonal balance with acute and chronic changes such as increase in cortisol and thyroid hormones, and simultaneous alterations in dehydroepiandrosterone sulphate, testosterone and insulin like growth factor-1 levels. The ability to cope with stress and regain previous healthy status, also called resiliency, is particularly impaired in older persons Thus, stressful conditions and hormonal dysregulation might concur to the onset of cognitive impairment in this population. In this review we address the relationship between stress hormones and cognitive function in older persons focusing on the role of one of the main stress factors, such as sleep deprivation (SD). We extracted and cross-checked data from 2000 to 2013 March and selected 112 full-text articles assessed for eligibility. In particular we considered 68 studies regarding the contribution of hormonal pathway to cognition in older adults, and 44 regarding hormones and SD both in rats and humans. We investigated how the activation of a stress-pattern response, like the one evoked from SD, can influence cognitive development and worsen cognitive status in the elderly. We will show the limited number of studies targeting the effects of SD and the consequent changes in stress hormones on cognitive function in this age group. We conclude that the current literature is not strong enough to give definitive answers on the role of stress hormonal pathway to the development of cognitive impairment in older individuals.

Effects of antiepileptic treatment on sleep and seizures in nocturnal frontal lobe epilepsy.

OBJECTIVE To study the effects of antiepileptic treatment on sleep parameters and video-polysomnography (VPSG) seizures in nocturnal frontal lobe epilepsy (NFLE). METHODS Twenty patients with a clinical and VPSG diagnosis of NFLE (baseline polysomnography [PSG]) underwent a clinical follow-up and performed a second VPSG after effective antiepileptic treatment lasting for at least 6 months. Conventional sleep measures, cyclic alternating pattern (CAP) parameters, and objective VPSG seizures were assessed in NFLE patients before and after treatment and were compared with the results of 20 age- and gender-matched control subjects. RESULTS Antiepileptic treatment determined a partial reduction of objective VPSG seizures of approximately 25% compared to baseline condition. Alterations of most conventional sleep measures recovered normal values, but nonrapid eye movement (NREM) sleep instability remained pathologically enhanced (CAP rate, +26% compared to controls) and was associated with persistence of daytime sleepiness. CONCLUSIONS Residual epileptic events and high levels of unstable NREM sleep can define a sort of objective resistance of both seizures and disturbed arousal system to the therapeutic purpose of the antiepileptic drugs in NFLE. This finding could determine the need for new therapeutic options in this particular form of epilepsy.

Acute shift of a case of moderate obstructive sleep apnea syndrome towards one of severe central sleep apnea syndrome after an ischemic stroke.

Article history: Received 21 December 2011 Received in revised form 12 January 2012 Accepted 27 January 2012 Available online 22 March 2012

Complex sleep apnea syndrome in stroke patients

Fig. 1. A profile of Tiberius Claudius Germanicus appears on the obverse of this silver denarius struck during the Imperial Roman Era (ca. first century CE; photo provided courtesy of A Pangerl of www.romancoins.info). To the Editor We would like to thank Dr. Sacchetti and co-workers for their interest in our article [1]. Sacchetti et al. raise the question whether a stroke may transform, in selected patients, an obstructive sleep apnea syndrome (OSAHS) into a complex-sleep apnea syndrome (Comp-SAS) and postulate that the appearance of central respiratory events may represent a stable consequence of stroke, and may complicate the treatment approach to sleep apnea. This hypothesis is supported by their preliminary data showing mixed (obstructive and central) apneas four months after the stroke. This high prevalence of central and mixed respiratory events in stable phase after stroke is higher than that found in other studies, about the time course of sleep breathing disorders and central periodic breathing in stroke patients [2,3]. These data also contradict in part the attenuation of central respiratory events within week or a few months after the stroke described by the same authors or in OSAHS patients with CompSAS [4]. In OSAHS patients some predictive factors for appearance of CompSAS during CPAP treatment have been proposed [5], which include atrial fibrillation, use of opioids, sleep disruption and features of initial sleep apnea syndrome (in term of severity of obstructive apneas and presence of relevant mixed/central events). The last two factors are probably strictly related to the fluctuations of ventilatory control system and CO2 levels, that we documented in our paper [1], as well as, the fluctuations of arousal system in NREM sleep that have been described as possible distinctive patterns of some patients with OSAHS [6]. Finally, in our opinion, the question is to clarify if these or other factors can tell us whether initial ‘‘complex’’ cases of OSAHS are more prone to develop a clear CompSAS after a stroke and, whether as suggestedbySacchetti andco-workers, tomerge this ‘‘pre-stroke’’ profile of sleep disordered breathing with ‘‘post-stroke’’ features. Thismay enable us to findout possible factors able to distinguish patientswith a transient CompSAS frompatientswith a persistent one.

Atypical patterns in portable monitoring for sleep apnoea: features of nocturnal epilepsy?

Atypical cardiorespiratory patterns can be found during routine clinical use of portable monitoring for diagnosis of sleep-disordered breathing (SDB). Over 1,000 consecutive portable recordings were analysed to study the potential ictal nature of stereotyped cardiorespiratory and motor patterns. Snoring, airflow, thoracic effort, pulse rate, body position, oxygen saturation and activity of the anterior tibialis muscles were quantified. Recordings showing stereotyped polygraphic patterns recurring throughout the night, but without the features of sleep apnoea (apnoea/hypopnoea index <5 events·h−1), were selected for investigation. Once included in the study, patients underwent attended nocturnal video polysomnography. A total of 15 recordings showing repeated polygraphic patterns characterised by a sequence of microphone activation, respiratory activity atypical for sleep and wakefulness, heart rate acceleration and limb movements, followed by body position change, were selected for investigation. Once included in the study, patients underwent attended nocturnal video polysomnography that showed frontal epileptic discharges triggering periodic electroencephalographic arousals, autonomic activation and stereotyped motor patterns. A diagnosis of nocturnal frontal lobe epilepsy (NFLE) was established for all patients. NFLE should be taken into consideration in patients with stereotyped and recurrent behavioural features during portable monitoring carried out for diagnosis of SDB.